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Friedrich MU, Schappe L, Prasad S, Friedrich H, Fox MD, Zwergal A, Zee DS, Faßbender K, Dillmann KU. Midbrain lesion-induced disconjugate gaze: a unifying circuit mechanism of ocular alignment? J Neurol 2024; 271:2844-2849. [PMID: 38353747 PMCID: PMC11055718 DOI: 10.1007/s00415-023-12155-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/03/2023] [Accepted: 12/07/2023] [Indexed: 04/28/2024]
Abstract
BACKGROUND Disconjugate eye movements are essential for depth perception in frontal-eyed species, but their underlying neural substrates are largely unknown. Lesions in the midbrain can cause disconjugate eye movements. While vertically disconjugate eye movements have been linked to defective visuo-vestibular integration, the pathophysiology and neuroanatomy of horizontally disconjugate eye movements remains elusive. METHODS A patient with a solitary focal midbrain lesion was examined using detailed clinical ocular motor assessments, binocular videooculography and diffusion-weighted MRI, which was co-registered to a high-resolution cytoarchitectonic MR-atlas. RESULTS The patient exhibited both vertically and horizontally disconjugate eye alignment and nystagmus. Binocular videooculography showed a strong correlation of vertical and horizontal oscillations during fixation but not in darkness. Oscillation intensities and waveforms were modulated by fixation, illumination, and gaze position, suggesting shared visual- and vestibular-related mechanisms. The lesion was mapped to a functionally ill-defined area of the dorsal midbrain, adjacent to the posterior commissure and sparing nuclei with known roles in vertical gaze control. CONCLUSION A circumscribed region in the dorsal midbrain appears to be a key node for disconjugate eye movements in both vertical and horizontal planes. Lesioning this area produces a unique ocular motor syndrome mirroring hallmarks of developmental strabismus and nystagmus. Further circuit-level studies could offer pivotal insights into shared pathomechanisms of acquired and developmental disorders affecting eye alignment.
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Affiliation(s)
- Maximilian U Friedrich
- Center for Brain Circuit Therapeutics, Brigham and Women's Hospital, 60 Fenwood Rd, Boston, MA, 02115, USA
- Harvard Medical School, Boston, USA
| | - Laurin Schappe
- Department of Neurology, Saarland University Medical Center, Homburg, Germany.
| | - Sashank Prasad
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Pennsylvania, USA
| | - Helen Friedrich
- Center for Brain Circuit Therapeutics, Brigham and Women's Hospital, 60 Fenwood Rd, Boston, MA, 02115, USA
| | - Michael D Fox
- Center for Brain Circuit Therapeutics, Brigham and Women's Hospital, 60 Fenwood Rd, Boston, MA, 02115, USA
- Harvard Medical School, Boston, USA
| | - Andreas Zwergal
- German Center for Vertigo and Dizziness, University Hospital, LMU Munich, Munich, Germany
- Department of Neurology, University Hospital, LMU Munich, Munich, Germany
| | - David S Zee
- Departments of Neurology, Ophthalmology, Otolaryngology, Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, USA
| | - Klaus Faßbender
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Pennsylvania, USA
| | - Klaus-Ulrich Dillmann
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Pennsylvania, USA
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Pogson JM, Shemesh A, Roberts DC, Zee DS, Otero-Milan J, Ward BK. Longer duration entry mitigates nystagmus and vertigo in 7-Tesla MRI. Front Neurol 2023; 14:1255105. [PMID: 38046576 PMCID: PMC10690370 DOI: 10.3389/fneur.2023.1255105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 10/10/2023] [Indexed: 12/05/2023] Open
Abstract
Introduction Patients and technologists commonly describe vertigo, dizziness, and imbalance near high-field magnets, e.g., 7-Tesla (T) magnetic resonance imaging (MRI) scanners. We sought a simple way to alleviate vertigo and dizziness in high-field MRI scanners by applying the understanding of the mechanisms behind magnetic vestibular stimulation and the innate characteristics of vestibular adaptation. Methods We first created a three-dimensional (3D) control systems model of the direct and indirect vestibulo-ocular reflex (VOR) pathways, including adaptation mechanisms. The goal was to develop a paradigm for human participants undergoing a 7T MRI scan to optimize the speed and acceleration of entry into and exit from the MRI bore to minimize unwanted vertigo. We then applied this paradigm from the model by recording 3D binocular eye movements (horizontal, vertical, and torsion) and the subjective experience of eight normal individuals within a 7T MRI. The independent variables were the duration of entry into and exit from the MRI bore, the time inside the MRI bore, and the magnetic field strength; the dependent variables were nystagmus slow-phase eye velocity (SPV) and the sensation of vertigo. Results In the model, when the participant was exposed to a linearly increasing magnetic field strength, the per-peak (after entry into the MRI bore) and post-peak (after exiting the MRI bore) responses of nystagmus SPV were reduced with increasing duration of entry and exit, respectively. There was a greater effect on the per-peak response. The entry/exit duration and peak response were inversely related, and the nystagmus was decreased the most with the 5-min duration paradigm (the longest duration modeled). The experimental nystagmus pattern of the eight normal participants matched the model, with increasing entry duration having the strongest effect on the per-peak response of nystagmus SPV. Similarly, all participants described less vertigo with the longer duration entries. Conclusion Increasing the duration of entry into and exit out of a 7T MRI scanner reduced or eliminated vertigo symptoms and reduced nystagmus peak SPV. Model simulations suggest that central processes of vestibular adaptation account for these effects. Therefore, 2-min entry and 20-s exit durations are a practical solution to mitigate vertigo and other discomforting symptoms associated with undergoing 7T MRI scans. In principle, these findings also apply to different magnet strengths.
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Affiliation(s)
- Jacob M. Pogson
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Neurology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia
| | - Ari Shemesh
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Ophthalmology, Hadassah Medical Center, Jerusalem, Israel
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA, United States
| | - Dale C. Roberts
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Neuroscience, The Johns Hopkins University, Baltimore, MD, United States
| | - David S. Zee
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Neuroscience, The Johns Hopkins University, Baltimore, MD, United States
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Wilmer Eye Institute, The Johns Hopkins University, Baltimore, MD, United States
| | - Jorge Otero-Milan
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA, United States
| | - Bryan K. Ward
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
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Tarnutzer AA, Gold D, Wang Z, Robinson KA, Kattah JC, Mantokoudis G, Tehrani ASS, Zee DS, Edlow JA, Newman-Toker DE. Impact of Clinician Training Background and Stroke Location on Bedside Diagnostic Test Accuracy in the Acute Vestibular Syndrome - A Meta-Analysis. Ann Neurol 2023; 94:295-308. [PMID: 37038843 PMCID: PMC10524166 DOI: 10.1002/ana.26661] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/24/2023] [Accepted: 03/30/2023] [Indexed: 04/12/2023]
Abstract
OBJECTIVE Acute dizziness/vertigo is usually due to benign inner-ear causes but is occasionally due to dangerous neurologic ones, particularly stroke. Because symptoms and signs overlap, misdiagnosis is frequent and overuse of neuroimaging is common. We assessed the accuracy of bedside findings to differentiate peripheral vestibular from central neurologic causes. METHODS We performed a systematic search (MEDLINE and Embase) to identify studies reporting on diagnostic accuracy of physical examination in adults with acute, prolonged dizziness/vertigo ("acute vestibular syndrome" [AVS]). Diagnostic test properties were calculated for findings. Results were stratified by examiner type and stroke location. RESULTS We identified 6,089 citations and included 14 articles representing 10 study cohorts (n = 800). The Head Impulse, Nystagmus, Test of Skew (HINTS) eye movement battery had high sensitivity 95.3% (95% confidence interval [CI] = 92.5-98.1) and specificity 92.6% (95% CI = 88.6-96.5). Sensitivity was similar by examiner type (subspecialists 94.3% [95% CI = 88.2-100.0] vs non-subspecialists 95.0% [95% CI = 91.2-98.9], p = 0.55), but specificity was higher among subspecialists (97.6% [95% CI = 94.9-100.0] vs 89.1% [95% CI = 83.0-95.2], p = 0.007). HINTS sensitivity was lower in anterior cerebellar artery (AICA) than posterior inferior cerebellar artery (PICA) strokes (84.0% [95% CI = 65.3-93.6] vs 97.7% [95% CI = 93.3-99.2], p = 0.014) but was "rescued" by the addition of bedside hearing tests (HINTS+). Severe (grade 3) gait/truncal instability had high specificity 99.2% (95% CI = 97.8-100.0) but low sensitivity 35.8% (95% CI = 5.2-66.5). Early magnetic resonance imaging (MRI)-diffusion-weighted imaging (DWI; within 24-48 hours) was falsely negative in 15% of strokes (sensitivity 85.1% [95% CI = 79.2-91.0]). INTERPRETATION In AVS, HINTS examination by appropriately trained clinicians can differentiate peripheral from central causes and has higher diagnostic accuracy for stroke than MRI-DWI in the first 24-48 hours. These techniques should be disseminated to all clinicians evaluating dizziness/vertigo. ANN NEUROL 2023;94:295-308.
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Affiliation(s)
- Alexander A. Tarnutzer
- Neurology, Cantonal Hospital of Baden, Baden, Switzerland
- Faculty of Medicine, University of Zurich, Zurich, Switzerland
| | - Daniel Gold
- Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, MD
| | - Zheyu Wang
- Division of Biostatistics and Bioinformatics, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine
- Johns Hopkins Bloomberg School of Public Health, Department of Biostatistics, Baltimore, MD
| | - Karen A. Robinson
- Johns Hopkins University School of Medicine, Department of Medicine, Baltimore, MD
| | | | - Georgios Mantokoudis
- Department of Otorhinolaryngology, Head and Neck Surgery, lnselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Ali S. Saber Tehrani
- Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, MD
| | - David S. Zee
- Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, MD
| | - Jonathan A. Edlow
- Department of Emergency Medicine, Beth Israel Deaconess Medical Center, Boston, MA
- Harvard Medical School, Boston, MA
| | - David E. Newman-Toker
- Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, MD
- Johns Hopkins Bloomberg School of Public Health, Department of Epidemiology, Baltimore, MD
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Kerkeni H, Zee DS, Korda A, Morrison M, Mantokoudis G, Ramat S. Corrective saccades in acute vestibular neuritis: studying the role of prediction with automated passively induced head impulses. J Neurophysiol 2023; 129:445-454. [PMID: 36651642 DOI: 10.1152/jn.00382.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
When the demands for visual stabilization during head rotations overwhelm the ability of the vestibuloocular reflex (VOR) to produce compensatory eye movements, the brain produces corrective saccades that bring gaze toward the fixation target, even without visual cues (covert saccades). What triggers covert saccades and what might be the role of prediction in their generation are unknown. We studied 14 subjects with acute vestibular neuritis. To minimize variability of the stimulus, head impulses were imposed with a motorized torque generator with the subject on a bite bar. Predictable and unpredictable (timing, amplitude, direction) stimuli were compared. Distributions of covert corrective saccade latencies were analyzed with a "LATER" (linear approach to threshold with ergodic rate) approach. On the affected side, VOR gain was higher (0.47 ± 0.28 vs. 0.39 ± 0.22, P ≪ 0.001) with predictable than unpredictable head impulses, and gaze error at the end of the head movement was less (5.4 ± 3.3° vs. 6.9 ± 3.3°, P ≪ 0.001). Analyzing trials with covert saccades, gaze error at saccade end was significantly less with predictable than unpredictable head impulses (4.2 ± 2.8° vs. 5.5 ± 3.2°, P ≪ 0.001). Furthermore, covert corrective saccades occurred earlier with predictable than unpredictable head impulses (140 ± 37 vs. 153 ± 37 ms, P ≪ 0.001). Using a LATER analysis with reciprobit plots, we were able to divide covert corrective saccades into two classes, early and late, with a break point in the range of 88-98 ms. We hypothesized two rise-to-threshold decision mechanisms for triggering early and late covert corrective saccades, with the first being most engaged when stimuli are predictable.NEW & NOTEWORTHY We successfully used a LATER (linear approach to threshold with ergodic rate) analysis of the latencies of corrective saccades in patients with acute vestibular neuritis. We found two types of covert saccades: early (<90 ms) and late (>90 ms) covert saccades. Predictability led to an increase in VOR gain and a decrease in saccade latency.
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Affiliation(s)
- Hassen Kerkeni
- Department of Neurology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - David S Zee
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Athanasia Korda
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Miranda Morrison
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Georgios Mantokoudis
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Stefano Ramat
- Laboratory of Bioengineering, Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy
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Wang C, Bai Y, Tsang A, Bian Y, Gou Y, Lin YX, Zhao M, Wei TY, Desman JM, Taylor CO, Greenstein JL, Otero-Millan J, Liu TYA, Kheradmand A, Zee DS, Green KE. Deep Learning Model for Static Ocular Torsion Detection Using Synthetically Generated Fundus Images. Transl Vis Sci Technol 2023; 12:17. [PMID: 36630147 PMCID: PMC9840445 DOI: 10.1167/tvst.12.1.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Purpose The objective of the study is to develop deep learning models using synthetic fundus images to assess the direction (intorsion versus extorsion) and amount (physiologic versus pathologic) of static ocular torsion. Static ocular torsion assessment is an important clinical tool for classifying vertical ocular misalignment; however, current methods are time-intensive with steep learning curves for frontline providers. Methods We used a dataset (n = 276) of right eye fundus images. The disc-foveal angle was calculated using ImageJ to generate synthetic images via image rotation. Using synthetic datasets (n = 12,740 images per model) and transfer learning (the reuse of a pretrained deep learning model on a new task), we developed a binary classifier (intorsion versus extorsion) and a multiclass classifier (physiologic versus pathologic intorsion and extorsion). Model performance was evaluated on unseen synthetic and nonsynthetic data. Results On the synthetic dataset, the binary classifier had an accuracy and area under the receiver operating characteristic curve (AUROC) of 0.92 and 0.98, respectively, whereas the multiclass classifier had an accuracy and AUROC of 0.77 and 0.94, respectively. The binary classifier generalized well on the nonsynthetic data (accuracy = 0.94; AUROC = 1.00). Conclusions The direction of static ocular torsion can be detected from synthetic fundus images using deep learning methods, which is key to differentiate between vestibular misalignment (skew deviation) and ocular muscle misalignment (superior oblique palsies). Translational Relevance Given the robust performance of our models on real fundus images, similar strategies can be adopted for deep learning research in rare neuro-ophthalmologic diseases with limited datasets.
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Affiliation(s)
- Chen Wang
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Yunong Bai
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Ashley Tsang
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Yuhan Bian
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Yifan Gou
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Yan X. Lin
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Matthew Zhao
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Tony Y. Wei
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Jacob M. Desman
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Casey Overby Taylor
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Joseph L. Greenstein
- Johns Hopkins University Department of Biomedical Engineering, Baltimore, MD, USA
| | - Jorge Otero-Millan
- Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, MD, USA,University of California Berkeley, Herbert Wertheim School of Optometry and Vision Science, Berkeley, CA, USA
| | - Tin Yan Alvin Liu
- Johns Hopkins University School of Medicine, Department of Ophthalmology, Baltimore, MD, USA
| | - Amir Kheradmand
- Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, MD, USA
| | - David S. Zee
- Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, MD, USA
| | - Kemar E. Green
- Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, MD, USA
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Shemesh AA, Kocoglu K, Akdal G, Ala RT, Halmagyi GM, Zee DS, Otero-Millan J. Modeling the effect of gravity on periodic alternating nystagmus. J Neurol Sci 2022; 442:120407. [PMID: 36115220 DOI: 10.1016/j.jns.2022.120407] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 08/25/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022]
Abstract
Periodic alternating nystagmus (PAN) is a rare oscillatory ocular motor disorder. The effects of gravity on the dynamic behavior of PAN can be studied by monitoring the nystagmus while changing head orientation. Previous studies of patients with PAN reached different conclusions about the effect of changing the orientation of the head relative to gravity on the ongoing PAN, either no effect or a damping of the nystagmus within several minutes. What neuronal circuits could account for the difference in the effects of gravity among PAN patients? We modeled how the brain resolves the tilt-translation ambiguity in normal individuals and added an unstable, oscillatory vestibular system generating PAN. PAN was suppressed in our patient in ear-down positions, in a similar pattern to that of a previously reported patient. This effect was simulated by reducing the gain of the projection of the "rotation feedback" loop to the velocity-storage integrator to approximately 5% of its normal value. With normal "rotation feedback" PAN is expected to dissipate quickly as soon as the head is rotated away from upright position. Moreover, by disconnecting the rotation feedback completely (gain = zero) the model simulated PAN that was reported to be unaffected by gravity. Thus, understanding the effect of this single parameter, the gain of the rotation feedback, can explain the observed variability among our own and previous studies.
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Affiliation(s)
- Ari A Shemesh
- Department of Ophthalmology, Hadassah Medical Center, Jerusalem, Israel
| | - Koray Kocoglu
- Department of Neurosciences, Institute of Health Sciences, Dokuz Eylül University, İzmir, Turkey
| | - Gülden Akdal
- Department of Neurosciences, Institute of Health Sciences, Dokuz Eylül University, İzmir, Turkey; Department of Neurology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - Rahmi Tümay Ala
- Department of Neurology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - G Michael Halmagyi
- Department of Neurology, Royal Prince Alfred Hospital and University of Sydney, Sydney, Australia
| | - David S Zee
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Departments of Ophthalmology, Otolaryngology-Head and Neck Surgery and Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jorge Otero-Millan
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Herbert Wertheim School of Optometry & Vision Science, University of California Berkeley, Berkeley, CA, USA.
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Wagle N, Morkos J, Liu J, Reith H, Greenstein J, Gong K, Gangan I, Pakhomov D, Hira S, Komogortsev OV, Newman-Toker DE, Winslow R, Zee DS, Otero-Millan J, Green KE. aEYE: A deep learning system for video nystagmus detection. Front Neurol 2022; 13:963968. [PMID: 36034311 PMCID: PMC9403604 DOI: 10.3389/fneur.2022.963968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 07/20/2022] [Indexed: 11/25/2022] Open
Abstract
Background Nystagmus identification and interpretation is challenging for non-experts who lack specific training in neuro-ophthalmology or neuro-otology. This challenge is magnified when the task is performed via telemedicine. Deep learning models have not been heavily studied in video-based eye movement detection. Methods We developed, trained, and validated a deep-learning system (aEYE) to classify video recordings as normal or bearing at least two consecutive beats of nystagmus. The videos were retrospectively collected from a subset of the monocular (right eye) video-oculography (VOG) recording used in the Acute Video-oculography for Vertigo in Emergency Rooms for Rapid Triage (AVERT) clinical trial (#NCT02483429). Our model was derived from a preliminary dataset representing about 10% of the total AVERT videos (n = 435). The videos were trimmed into 10-sec clips sampled at 60 Hz with a resolution of 240 × 320 pixels. We then created 8 variations of the videos by altering the sampling rates (i.e., 30 Hz and 15 Hz) and image resolution (i.e., 60 × 80 pixels and 15 × 20 pixels). The dataset was labeled as "nystagmus" or "no nystagmus" by one expert provider. We then used a filtered image-based motion classification approach to develop aEYE. The model's performance at detecting nystagmus was calculated by using the area under the receiver-operating characteristic curve (AUROC), sensitivity, specificity, and accuracy. Results An ensemble between the ResNet-soft voting and the VGG-hard voting models had the best performing metrics. The AUROC, sensitivity, specificity, and accuracy were 0.86, 88.4, 74.2, and 82.7%, respectively. Our validated folds had an average AUROC, sensitivity, specificity, and accuracy of 0.86, 80.3, 80.9, and 80.4%, respectively. Models created from the compressed videos decreased in accuracy as image sampling rate decreased from 60 Hz to 15 Hz. There was only minimal change in the accuracy of nystagmus detection when decreasing image resolution and keeping sampling rate constant. Conclusion Deep learning is useful in detecting nystagmus in 60 Hz video recordings as well as videos with lower image resolutions and sampling rates, making it a potentially useful tool to aid future automated eye-movement enabled neurologic diagnosis.
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Affiliation(s)
- Narayani Wagle
- Department of Biomedical Engineering, The John Hopkins University, Baltimore, MD, United States
- Department of Computer Science, The Johns Hopkins University, Baltimore, MD, United States
| | - John Morkos
- The John Hopkins University School of Medicine, Baltimore, MD, United States
| | - Jingyan Liu
- Department of Biomedical Engineering, The John Hopkins University, Baltimore, MD, United States
| | - Henry Reith
- Department of Biomedical Engineering, The John Hopkins University, Baltimore, MD, United States
| | - Joseph Greenstein
- Institute for Computational Medicine, The Johns Hopkins University, Baltimore, MD, United States
| | - Kirby Gong
- Department of Biomedical Engineering, The John Hopkins University, Baltimore, MD, United States
| | - Indranuj Gangan
- Department of Biomedical Engineering, The John Hopkins University, Baltimore, MD, United States
| | - Daniil Pakhomov
- Department of Computer Science, The Johns Hopkins University, Baltimore, MD, United States
| | - Sanchit Hira
- Department of Biomedical Engineering, The John Hopkins University, Baltimore, MD, United States
| | - Oleg V. Komogortsev
- Department of Computer Science, Texas State University, San Marcos, TX, United States
| | - David E. Newman-Toker
- Institute for Computational Medicine, The Johns Hopkins University, Baltimore, MD, United States
- Departments of Ophthalmology and Otolaryngology, The John Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Emergency Medicine, The John Hopkins University School of Medicine, Baltimore, MD, United States
| | - Raimond Winslow
- Department of Biomedical Engineering, The John Hopkins University, Baltimore, MD, United States
- Department of Computer Science, The Johns Hopkins University, Baltimore, MD, United States
- Departments of Electrical and Computer Engineering, The John Hopkins University, Baltimore, MD, United States
| | - David S. Zee
- Institute for Computational Medicine, The Johns Hopkins University, Baltimore, MD, United States
- Departments of Electrical and Computer Engineering, The John Hopkins University, Baltimore, MD, United States
- Department of Neurosciences, The John Hopkins University School of Medicine, Baltimore, MD, United States
| | - Jorge Otero-Millan
- Department of Neurosciences, The John Hopkins University School of Medicine, Baltimore, MD, United States
- School of Optometry University of California–Berkeley, Berkeley, CA, United States
| | - Kemar E. Green
- Department of Biomedical Engineering, The John Hopkins University, Baltimore, MD, United States
- Institute for Computational Medicine, The Johns Hopkins University, Baltimore, MD, United States
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Kerkeni H, Brügger D, Mantokoudis G, Abegg M, Zee DS. Pharmacological and Behavioral Strategies to Improve Vision in Acquired Pendular Nystagmus. Am J Case Rep 2022; 23:e935148. [PMID: 35780294 PMCID: PMC9260699 DOI: 10.12659/ajcr.935148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Patient: Female, 49-year-old
Final Diagnosis: Acquired pendular nystagmus • multiple sclerosis
Symptoms: Oscillopsia
Medication: —
Clinical Procedure: Blink • visual acuity
Specialty: Neurology • Ophthalmology
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Affiliation(s)
- Hassen Kerkeni
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Dominik Brügger
- Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Georgios Mantokoudis
- Department of Otorhinolaryngology, Head and Neck Surgery, lnselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Mathias Abegg
- Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - David S. Zee
- Department of Neurology, Ophthalmology, Otolaryngology-Head and Neck Surgery, Johns Hopkins Hospital, Baltimore, USA, MD
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9
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Iannuzzelli K, Shi R, Carter R, Huynh R, Morgan O, Kuo SH, Bang J, Mills KA, Baranano K, Zee DS, Moukheiber E, Roda R, Butala A, Marvel C, Joyce M, Li X, Wang J, Rosenthal LS. The association between educational attainment and SCA 3 age of onset and disease course. Parkinsonism Relat Disord 2022; 98:99-102. [PMID: 35635856 PMCID: PMC10498785 DOI: 10.1016/j.parkreldis.2022.02.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 02/15/2022] [Accepted: 02/27/2022] [Indexed: 11/18/2022]
Abstract
BACKGROUND The number of trinucleotide CAG repeats is inversely correlated with the age at onset (AAO) of motor symptoms in individuals with Spinocerebellar Ataxia type 3 (SCA 3) and may be responsible for 50%-60% of the variability in AAO. Drawing from a social determinants of health model, we sought to determine if educational attainment further contributes to the AAO and motor symptom progression of SCA 3. METHODS We performed a retrospective chart review in which twenty individuals met criteria for inclusion and had been seen by an ataxia specialist at our hospital between January 2005 and July 2019. AAO of motor symptoms and Scale for Assessment and Rating of Ataxia (SARA) scores were used as primary outcome measures. RESULTS Using a linear regression, we found that having greater CAG repeat length and greater than 16 years of education results in an earlier AAO. The importance of the CAG repeat length on AAO, however, is greater amongst individuals with lower education. Using a linear mixed model evaluating SARA score over time with AAO, we found that less than 16 years of education is associated with faster progression of the disease. CONCLUSION In our group of SCA 3 patients, level of education correlated with both the AAO and SARA scores. Though our findings need to be confirmed with a larger cohort, our study suggests that level of education can have a strong influence on health outcomes in SCA 3 and possibly other groups of patients with ataxia.
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Affiliation(s)
| | - Rosa Shi
- Department of Arts and Sciences, Johns Hopkins University, United States
| | - Reece Carter
- Department of Arts and Sciences, Johns Hopkins University, United States
| | - Rachel Huynh
- Department of Medicine, Utah Health Sciences, United States
| | - Owen Morgan
- Department of Neurology, Johns Hopkins School of Medicine, United States
| | - Sheng-Han Kuo
- Department of Neurology, Columbia University, United States; Initiative for Columbia Ataxia and Tremor, Columbia University, United States
| | - Jee Bang
- Department of Neurology, Johns Hopkins School of Medicine, United States
| | - Kelly A Mills
- Department of Neurology, Johns Hopkins School of Medicine, United States
| | - Kristin Baranano
- Department of Neurology, Johns Hopkins School of Medicine, United States
| | - David S Zee
- Department of Neurology, Johns Hopkins School of Medicine, United States
| | - Emile Moukheiber
- Department of Neurology, Johns Hopkins School of Medicine, United States
| | - Ricardo Roda
- Department of Neurology, Johns Hopkins School of Medicine, United States
| | - Ankur Butala
- Department of Neurology, Johns Hopkins School of Medicine, United States
| | - Cherie Marvel
- Department of Neurology, Johns Hopkins School of Medicine, United States
| | - Michelle Joyce
- Department of Neurology, Johns Hopkins School of Medicine, United States
| | - Ximin Li
- Johns Hopkins Bloomberg School of Public Health, United States
| | - Jiangxia Wang
- Johns Hopkins Bloomberg School of Public Health, United States
| | - Liana S Rosenthal
- Department of Neurology, Johns Hopkins School of Medicine, United States.
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10
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Lee SU, Kim HJ, Choi JY, Choi JH, Zee DS, Kim JS. Correction to: Nystagmus only with fixation in the light: a rare central sign due to cerebellar malfunction. J Neurol 2022; 269:3891. [PMID: 35482081 DOI: 10.1007/s00415-022-11157-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Sun-Uk Lee
- Department of Neurology, Korea University Medical Center, Seoul, South Korea.,Department of Neurology, Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Hyo-Jung Kim
- Research Administration Team, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Gyeonggi-do, Seongnam-si, 13620, South Korea
| | - Jeong-Yoon Choi
- Department of Neurology, Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea.,Department of Neurology, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Jae-Hwan Choi
- Department of Neurology, Pusan National University School of Medicine, Pusan National University Yangsan Hospital, Yangsan, South Korea
| | - David S Zee
- Departments of Neurology, Ophthalmology, Otolaryngology-Head and Neck Surgery, and Neuroscience, Division of Neuro-Visual and Vestibular Disorders, Johns Hopkins Hospital, Baltimore, MD, USA
| | - Ji-Soo Kim
- Department of Neurology, Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea. .,Department of Neurology, Seoul National University Bundang Hospital, Seongnam, South Korea.
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11
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Lee SU, Kim HJ, Choi JY, Choi JH, Zee DS, Kim JS. Nystagmus only with fixation in the light: a rare central sign due to cerebellar malfunction. J Neurol 2022; 269:3879-3890. [PMID: 35396603 DOI: 10.1007/s00415-022-11108-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/24/2022] [Accepted: 03/25/2022] [Indexed: 11/30/2022]
Abstract
Fixation nystagmus refers to the nystagmus that appears or markedly increases with fixation. While relatively common in infantile (congenital) nystagmus, acquired fixation nystagmus is unusual and has been ascribed to lesions involving the cerebellar nuclei or the fibers projecting from the cerebellum to the brainstem. We aimed to report the clinical features of patients with acquired fixation nystagmus and discuss possible mechanisms using a model simulation and diagnostic significance. We describe four patients with acquired fixation nystagmus that appears or markedly increases with visual fixation. All patients had lesions involving the cerebellum or dorsal medulla. All patients showed direction-changing gaze-evoked nystagmus, impaired smooth pursuit, and decreased vestibular responses on head-impulse tests. The clinical implication of fixation nystagmus is that it may occur in central lesions that impair both smooth pursuit and the vestibulo-ocular reflex (VOR) but without creating a spontaneous nystagmus in the dark. We develop a mathematical model that hypothesizes that fixation nystagmus reflects a central tone imbalance due to abnormal function in cerebellar circuits that normally optimize the interaction between visual following (pursuit) and VOR during attempted fixation. Patients with fixation nystagmus have central lesions involving the cerebellar circuits that are involved in visual-vestibular interactions and normally eliminate biases that cause a spontaneous nystagmus.
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Affiliation(s)
- Sun-Uk Lee
- Department of Neurology, Korea University Medical Center, Seoul, South Korea.,Department of Neurology, Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Hyo-Jung Kim
- Research Administration Team, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Gyeonggi-do, Seongnam-si, 13620, South Korea
| | - Jeong-Yoon Choi
- Department of Neurology, Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea.,Department of Neurology, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Jae-Hwan Choi
- Department of Neurology, Pusan National University School of Medicine, Pusan National University Yangsan Hospital, Yangsan, South Korea
| | - David S Zee
- Departments of Neurology, Ophthalmology, Otolaryngology-Head and Neck Surgery, and Neuroscience, Division of Neuro-Visual and Vestibular Disorders, Johns Hopkins Hospital, Baltimore, MD, USA
| | - Ji-Soo Kim
- Department of Neurology, Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea. .,Department of Neurology, Seoul National University Bundang Hospital, Seongnam, South Korea.
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12
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Helmchen C, Machner B, Sprenger A, Zee DS. Monocular Patching Attenuates Vertical Nystagmus in Wernicke's Encephalopathy via Release of Activity in Subcortical Visual Pathways. Mov Disord Clin Pract 2022; 9:107-109. [PMID: 36988975 PMCID: PMC8721830 DOI: 10.1002/mdc3.13380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/19/2021] [Accepted: 10/24/2021] [Indexed: 11/06/2022] Open
Affiliation(s)
- Christoph Helmchen
- Department of NeurologyUniversity Hospital Schleswig‐HolsteinLübeckGermany
- Center of Brain, Behavior and Metabolism (CBBM)University of LübeckLübeckGermany
| | - Björn Machner
- Department of NeurologyUniversity Hospital Schleswig‐HolsteinLübeckGermany
- Center of Brain, Behavior and Metabolism (CBBM)University of LübeckLübeckGermany
| | - Andreas Sprenger
- Department of NeurologyUniversity Hospital Schleswig‐HolsteinLübeckGermany
- Center of Brain, Behavior and Metabolism (CBBM)University of LübeckLübeckGermany
- Institute of Psychology IIUniversity LübeckLübeckGermany
| | - David S. Zee
- Department of Neurology, Ophthalmology, Otolaryngology‐Head and Neck Surgery, and Neuroscience, Division of Neuro‐Visual and Vestibular DisordersThe Johns Hopkins HospitalBaltimoreMarylandUSA
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13
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Helmchen C, Machner B, Gablentz JVD, Sprenger A, Zee DS. Downbeat Nystagmus Is Abolished by Alcohol in Nonalcoholic Wernicke Encephalopathy. Neurol Clin Pract 2021; 12:e129-e132. [DOI: 10.1212/cpj.0000000000001138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 09/20/2021] [Indexed: 11/15/2022]
Abstract
ABSTRACTObjective:Lesions of the cerebellar flocculus cause enduring downbeat nystagmus (DBN) with unrelenting oscillopsia. Unlike most DBN patients, the flocculus is structurally spared in non-alcoholic Wernicke’s encephalopathy (nWE) with chronic DBN. The objective was to study the effects of alcohol in nWE.Methods:We recorded eye movements of a unique patient with nWE under controlled alcohol consumption who said his oscillopsia disappeared with alcohol.Results:His downbeat nystagmus was markedly diminished by alcohol (by 77.4%) though he remained alert with normal saccades.Conclusion:This striking observation may be caused by the differential effect of alcohol on the perihypoglossal complex and the paramedian tract neurons, which control the level of activity in the flocculus, with opposite (inhibition and excitation, respectively) effects. The finding suggests new ideas about the treatment and pathophysiology of DBN with a structurally-intact cerebellum.
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14
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Green KE, Pogson JM, Otero-Millan J, Gold DR, Tevzadze N, Saber Tehrani AS, Zee DS, Newman-Toker DE, Kheradmand A. Author Response: Opinion and Special Articles: Remote Evaluation of Acute Vertigo Strategies and Technological Considerations. Neurology 2021; 97:652. [PMID: 34580187 DOI: 10.1212/wnl.0000000000012630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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15
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Sadeghpour S, Fornasari F, Otero-Millan J, Carey JP, Zee DS, Kheradmand A. Evaluation of the Video Ocular Counter-Roll (vOCR) as a New Clinical Test of Otolith Function in Peripheral Vestibulopathy. JAMA Otolaryngol Head Neck Surg 2021; 147:518-525. [PMID: 33764386 DOI: 10.1001/jamaoto.2021.0176] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Importance Video-oculography (VOG) goggles have been integrated into the assessment of semicircular canal function in patients with vestibular disorders. However, a similar bedside VOG method for testing otolith function is lacking. Objective To evaluate the use of VOG-based measurement of ocular counter-roll (vOCR) as a clinical test of otolith function. Design, Setting, and Participants A case-control study was conducted to compare vOCR measurement among patients at various stages of unilateral loss of vestibular function with healthy controls. The receiver operating characteristic curve method was used to determine the diagnostic accuracy of the vOCR test in detecting loss of otolith function. Participants were recruited at a tertiary center including the Johns Hopkins outpatient clinic and Johns Hopkins Hospital, Baltimore, Maryland. Participants included 56 individuals with acute (≤4 weeks after surgery), subacute (4 weeks-6 months after surgery), and chronic (>6 months after surgery) unilateral vestibular loss as well as healthy controls. A simple bedside maneuver with en bloc, 30° lateral tilt of the head and trunk was used for vOCR measurement. The study was conducted from February 2, 2017, to March 10, 2019. Intervention In each participant vOCR was measured during static tilts of the head and trunk en bloc. Main Outcomes and Measures The vOCR measurements and diagnostic accuracy of vOCR in detecting patients with loss of vestibular function from healthy controls. Results Of the 56 participants, 28 (50.0%) were men; mean (SD) age was 53.5 (11.4) years. The mean (SD) time of acute unilateral vestibular loss was 9 (7) days (range, 2-17 days) in the acute group, 61 (39) days (range, 28-172 days) in the subacute group, and 985 (1066) days (range 185-4200 days) in the chronic group. The vOCR test showed reduction on the side of vestibular loss, and the deficit was greater in patients with acute and subacute vestibular loss than in patients with chronic loss and healthy controls (acute vs chronic: -1.81°; 95% CI, -3.45° to -0.17°; acute vs control: -3.18°; 95% CI, -4.83° to -1.54°; subacute vs chronic: -0.63°; 95% CI, -2.28° to 1.01°; subacute vs control: -2.01°; 95% CI, -3.65° to -0.36°; acute vs subacute: -1.17°; 95% CI, -2.88° to 0.52°; and chronic vs control: -1.37°; 95% CI, -2.96° to 0.21°). The asymmetry in vOCR between the side of vestibular loss and healthy side was significantly higher in patients with acute vs chronic loss (0.28; 95% CI, 0.06-0.51). Overall, the performance of the vOCR test in discriminating between patients with vestibular loss and healthy controls was 0.83 (area under the receiver operating characteristic curve). The best vOCR threshold to detect vestibular loss at the 30° tilt was 4.5°, with a sensitivity of 80% (95% CI, 0.62%-0.88%) and specificity of 82% (95% CI, 0.57%-1.00%). Conclusions and Relevance The findings of this case-control study suggest that the vOCR test can be performed with a simple bedside maneuver and may be used to detect or track loss of otolith function.
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Affiliation(s)
- Shirin Sadeghpour
- Vestibular and Ocular motor (VOR) Laboratory, Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Francesco Fornasari
- Vestibular and Ocular motor (VOR) Laboratory, Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Jorge Otero-Millan
- Vestibular and Ocular motor (VOR) Laboratory, Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Optometry and Vision Science, University of California, Berkeley
| | - John P Carey
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - David S Zee
- Vestibular and Ocular motor (VOR) Laboratory, Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Amir Kheradmand
- Vestibular and Ocular motor (VOR) Laboratory, Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland
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16
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Shemesh AA, Kocoglu K, Akdal G, Ala RT, Halmagyi GM, Zee DS, Otero-Millan J. Modeling the interaction among three cerebellar disorders of eye movements: periodic alternating, gaze-evoked and rebound nystagmus. J Comput Neurosci 2021; 49:295-307. [PMID: 34003422 PMCID: PMC9169448 DOI: 10.1007/s10827-021-00790-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 04/28/2021] [Accepted: 05/04/2021] [Indexed: 10/21/2022]
Abstract
A woman, age 44, with a positive anti-YO paraneoplastic cerebellar syndrome and normal imaging developed an ocular motor disorder including periodic alternating nystagmus (PAN), gaze-evoked nystagmus (GEN) and rebound nystagmus (RN). During fixation there was typical PAN but changes in gaze position evoked complex, time-varying oscillations of GEN and RN. To unravel the pathophysiology of this unusual pattern of nystagmus, we developed a mathematical model of normal function of the circuits mediating the vestibular-ocular reflex and gaze-holding including their adaptive mechanisms. Simulations showed that all the findings of our patient could be explained by two, small, isolated changes in cerebellar circuits: reducing the time constant of the gaze-holding integrator, producing GEN and RN, and increasing the gain of the vestibular velocity-storage positive feedback loop, producing PAN. We conclude that the gaze- and time-varying pattern of nystagmus in our patient can be accounted for by superposition of one model that produces typical PAN and another model that produces typical GEN and RN, without requiring a new oscillator in the gaze-holding system or a more complex, nonlinear interaction between the two models. This analysis suggest a strategy for uncovering gaze-evoked and rebound nystagmus in the setting of a time-varying nystagmus such as PAN. Our results are also consistent with current ideas of compartmentalization of cerebellar functions for the control of the vestibular velocity-storage mechanism (nodulus and ventral uvula) and for holding horizontal gaze steady (the flocculus and tonsil).
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Affiliation(s)
- Ari A Shemesh
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Koray Kocoglu
- Department of Neurosciences, Institute of Health Sciences, Dokuz Eylül University, İzmir, Turkey
| | - Gülden Akdal
- Department of Neurosciences, Institute of Health Sciences, Dokuz Eylül University, İzmir, Turkey
- Department of Neurology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - Rahmi Tümay Ala
- Department of Neurology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - G Michael Halmagyi
- Department of Neurology, Royal Prince Alfred Hospital and University of Sydney, Sydney, Australia
| | - David S Zee
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Departments of Ophthalmology, Otolaryngology-Head and Neck Surgery and Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jorge Otero-Millan
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- School of Optometry, University of California Berkeley, Berkeley, CA, USA.
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17
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Mantokoudis G, Korda A, Zee DS, Zamaro E, Sauter TC, Wagner F, Caversaccio MD. Bruns' nystagmus revisited: A sign of stroke in patients with the acute vestibular syndrome. Eur J Neurol 2021; 28:2971-2979. [PMID: 34176187 PMCID: PMC8456911 DOI: 10.1111/ene.14997] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 06/24/2021] [Indexed: 11/29/2022]
Abstract
Objective Gaze‐evoked nystagmus (GEN) is a central sign in patients with the acute vestibular syndrome (AVS); however, discriminating between a pathological and a physiologic GEN is a challenge. Here we evaluate GEN in patients with AVS. Methods In this prospective cross‐sectional study, we used video‐oculography (VOG) to compare GEN in the light (target at 15° eccentric) in 64 healthy subjects with 47 patients seen in the emergency department (ED) who had AVS; 35 with vestibular neuritis and 12 with stroke. All patients with an initial non‐diagnostic MRI received a confirmatory, delayed MRI as a reference standard in detecting stroke. Results Healthy subjects with GEN had a time constant of centripetal drift >18 s. VOG identified pathologic GEN (time constant ≤ 18 s) in 33% of patients with vestibular strokes, specificity was 100%, accuracy was 83%. Results were equivalent to examination by a clinical expert. As expected, since all patients with GEN had a SN in straight‐ahead position, they showed the pattern of a Bruns’ nystagmus. Conclusions One third of patients with AVS due to central vestibular strokes had a spontaneous SN in straight‐ahead gaze and a pathological GEN, producing the pattern of a Bruns’ nystagmus with a shift of the null position. The localization of the side of the lesion based on the null was not consistent, presumably because the circuits underlying gaze‐holding are widespread in the brainstem and cerebellum. Nevertheless, automated quantification of GEN with VOG was specific, and accurately identified patients in the ED with AVS due to strokes.
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Affiliation(s)
- Georgios Mantokoudis
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Athanasia Korda
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - David S Zee
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ewa Zamaro
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Thomas C Sauter
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Franca Wagner
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Marco D Caversaccio
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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18
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Rucker JC, Zee DS. Cerebellum-Editorial Regarding Consensus Paper Consensus on Virtual Management of Vestibular Disorders: Urgent Versus Expedited Care. Shaikh et al., doi.org/10.1007/s12311-020-01178-8 : The Return of the House Call: Evaluating Acutely Ill Patients with Vertigo in the Era of Virtual Health Care. Cerebellum 2021; 20:1-3. [PMID: 32875488 PMCID: PMC7462732 DOI: 10.1007/s12311-020-01184-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Janet C Rucker
- Departments of Neurology and Ophthalmology, NYU Grossman School of Medicine, 222 East 41st Street, 14th Floor, New York, NY, 10017, USA.
| | - David S Zee
- Departments of Neurology, Otolaryngology-Head and Neck Surgery, Ophthalmology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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19
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Korda A, Zee DS, Wyss T, Zamaro E, Caversaccio MD, Wagner F, Kalla R, Mantokoudis G. Impaired fixation suppression of horizontal vestibular nystagmus during smooth pursuit: pathophysiology and clinical implications. Eur J Neurol 2021; 28:2614-2621. [PMID: 33983645 PMCID: PMC8362184 DOI: 10.1111/ene.14909] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 05/04/2021] [Accepted: 05/05/2021] [Indexed: 12/27/2022]
Abstract
Background and purpose A peripheral spontaneous nystagmus (SN) is typically enhanced or revealed by removing fixation. Conversely, failure of fixation suppression of SN is usually a sign of a central disorder. Based on Luebke and Robinson (Vision Res 1988, vol. 28 (8), pp. 941–946), who suggested that the normal fixation mechanism is disengaged during pursuit, it is hypothesized that vertical tracking in the light would bring out or enhance a horizontal SN. Methods Eighteen patients with acute vestibular neuritis were studied. Eye movements were recorded using video‐oculography at straight‐ahead gaze with and without visual fixation, and during smooth pursuit. The slow‐phase velocity and the fixation suppression indices of nystagmus (relative to SN in darkness) were compared in each condition. Results During vertical tracking, the slow‐phase velocity of horizontal SN with eyes near straight‐ahead gaze was significantly higher (median 2.7°/s) than under static visual fixation (median 1.2°/s). Likewise, the fixation index was significantly higher (worse suppression) during pursuit (median 48%) than during fixation (median 26%). A release of SN was also suggested during horizontal pursuit, if one assumes superposition of SN on a normal and symmetrical pursuit capability.
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Affiliation(s)
- Athanasia Korda
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland
| | - David S Zee
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Thomas Wyss
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland
| | - Ewa Zamaro
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland
| | - Marco D Caversaccio
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland
| | - Franca Wagner
- University Institute of Diagnostic and Interventional Neuroradiology, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland
| | - Roger Kalla
- Department of Neurology, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland
| | - Georgios Mantokoudis
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland
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20
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Mastrangelo V, Merli E, Rucker JC, Eggenberger ER, Zee DS, Cortelli P. Neuro-Ophthalmological Findings in Early Fatal Familial Insomnia. Ann Neurol 2021; 89:823-827. [PMID: 33386648 DOI: 10.1002/ana.26008] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 12/28/2020] [Accepted: 12/29/2020] [Indexed: 11/08/2022]
Abstract
Fatal familial insomnia (FFI) is a rare inherited prion disease characterized by sleep, autonomic, and motor disturbances. Neuro-ophthalmological abnormalities have been reported at the onset of disease, although not further characterized. We analyzed video recordings of eye movements of 6 patients with FFI from 3 unrelated kindreds, seen within 6 months from the onset of illness. Excessive saccadic intrusions were the most prominent findings. In patients with severe insomnia, striking saccadic intrusions are an early diagnostic clue for FFI. The fact that the thalamus is the first structure affected in FFI also suggests its role in the control of steady fixation. ANN NEUROL 2021;89:823-827.
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Affiliation(s)
- Vincenzo Mastrangelo
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Elena Merli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Janet C Rucker
- Department of Neurology, New York University School of Medicine, New York, NY.,Department of Ophthalmology, New York University School of Medicine, New York, NY
| | - Eric R Eggenberger
- Departments of Ophthalmology, Neurology, and Neurosurgery, Mayo Clinic, Jacksonville, FL
| | - David S Zee
- Departments of Neurology, Ophthalmology, Otolaryngology-Head and Neck Surgery, and Neuroscience, Division of Neuro-Visual and Vestibular Disorders, Johns Hopkins Hospital, Baltimore, MD
| | - Pietro Cortelli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.,IRCCS Istituto delle Scienze Neurologiche, UOC Clinica Neurologica Rete Metropolitana NEUROMET, Bologna, Italy
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21
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Green KE, Pogson JM, Otero-Millan J, Gold DR, Tevzadze N, Saber Tehrani AS, Zee DS, Newman-Toker DE, Kheradmand A. Opinion and Special Articles: Remote Evaluation of Acute Vertigo: Strategies and Technological Considerations. Neurology 2021; 96:34-38. [PMID: 33004609 PMCID: PMC7884977 DOI: 10.1212/wnl.0000000000010980] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Patients with acute vestibular disorders are often a diagnostic challenge for neurologists, especially when the evaluation must be conducted remotely. The clinical dilemma remains: Does the patient have a benign peripheral inner ear problem or a worrisome central vestibular disorder, such as a stroke? The use of a focused history and the virtual HINTS (head impulse test, nystagmus evaluation, and test of skew) examination are key steps towards correctly diagnosing and triaging the acute vertiginous patient. When looking for signs of vestibulo-ocular dysfunction, there are important technological and practical considerations for an effective clinical interpretation.
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Affiliation(s)
- Kemar E Green
- From the Departments of Neurology (K.E.G., J.M.P., J.O.-M., D.R.G., N.T., A.S.S.T., D.S.Z., D.E.N.-T., A.K.), Otolaryngology-Head and Neck Surgery (D.R.G., D.S.Z., D.E.N.-T., A.K.), Ophthalmology (D.R.G., D.S.Z., D.E.N.-T.), Emergency Medicine (D.R.G.), Neurosurgery & Medicine (D.R.G.), and Neuroscience (D.S.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and School of Optometry (J.O.-M.), University of California, Berkeley.
| | - Jacob M Pogson
- From the Departments of Neurology (K.E.G., J.M.P., J.O.-M., D.R.G., N.T., A.S.S.T., D.S.Z., D.E.N.-T., A.K.), Otolaryngology-Head and Neck Surgery (D.R.G., D.S.Z., D.E.N.-T., A.K.), Ophthalmology (D.R.G., D.S.Z., D.E.N.-T.), Emergency Medicine (D.R.G.), Neurosurgery & Medicine (D.R.G.), and Neuroscience (D.S.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and School of Optometry (J.O.-M.), University of California, Berkeley
| | - Jorge Otero-Millan
- From the Departments of Neurology (K.E.G., J.M.P., J.O.-M., D.R.G., N.T., A.S.S.T., D.S.Z., D.E.N.-T., A.K.), Otolaryngology-Head and Neck Surgery (D.R.G., D.S.Z., D.E.N.-T., A.K.), Ophthalmology (D.R.G., D.S.Z., D.E.N.-T.), Emergency Medicine (D.R.G.), Neurosurgery & Medicine (D.R.G.), and Neuroscience (D.S.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and School of Optometry (J.O.-M.), University of California, Berkeley
| | - Daniel R Gold
- From the Departments of Neurology (K.E.G., J.M.P., J.O.-M., D.R.G., N.T., A.S.S.T., D.S.Z., D.E.N.-T., A.K.), Otolaryngology-Head and Neck Surgery (D.R.G., D.S.Z., D.E.N.-T., A.K.), Ophthalmology (D.R.G., D.S.Z., D.E.N.-T.), Emergency Medicine (D.R.G.), Neurosurgery & Medicine (D.R.G.), and Neuroscience (D.S.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and School of Optometry (J.O.-M.), University of California, Berkeley
| | - Nana Tevzadze
- From the Departments of Neurology (K.E.G., J.M.P., J.O.-M., D.R.G., N.T., A.S.S.T., D.S.Z., D.E.N.-T., A.K.), Otolaryngology-Head and Neck Surgery (D.R.G., D.S.Z., D.E.N.-T., A.K.), Ophthalmology (D.R.G., D.S.Z., D.E.N.-T.), Emergency Medicine (D.R.G.), Neurosurgery & Medicine (D.R.G.), and Neuroscience (D.S.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and School of Optometry (J.O.-M.), University of California, Berkeley
| | - Ali S Saber Tehrani
- From the Departments of Neurology (K.E.G., J.M.P., J.O.-M., D.R.G., N.T., A.S.S.T., D.S.Z., D.E.N.-T., A.K.), Otolaryngology-Head and Neck Surgery (D.R.G., D.S.Z., D.E.N.-T., A.K.), Ophthalmology (D.R.G., D.S.Z., D.E.N.-T.), Emergency Medicine (D.R.G.), Neurosurgery & Medicine (D.R.G.), and Neuroscience (D.S.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and School of Optometry (J.O.-M.), University of California, Berkeley
| | - David S Zee
- From the Departments of Neurology (K.E.G., J.M.P., J.O.-M., D.R.G., N.T., A.S.S.T., D.S.Z., D.E.N.-T., A.K.), Otolaryngology-Head and Neck Surgery (D.R.G., D.S.Z., D.E.N.-T., A.K.), Ophthalmology (D.R.G., D.S.Z., D.E.N.-T.), Emergency Medicine (D.R.G.), Neurosurgery & Medicine (D.R.G.), and Neuroscience (D.S.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and School of Optometry (J.O.-M.), University of California, Berkeley
| | - David E Newman-Toker
- From the Departments of Neurology (K.E.G., J.M.P., J.O.-M., D.R.G., N.T., A.S.S.T., D.S.Z., D.E.N.-T., A.K.), Otolaryngology-Head and Neck Surgery (D.R.G., D.S.Z., D.E.N.-T., A.K.), Ophthalmology (D.R.G., D.S.Z., D.E.N.-T.), Emergency Medicine (D.R.G.), Neurosurgery & Medicine (D.R.G.), and Neuroscience (D.S.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and School of Optometry (J.O.-M.), University of California, Berkeley
| | - Amir Kheradmand
- From the Departments of Neurology (K.E.G., J.M.P., J.O.-M., D.R.G., N.T., A.S.S.T., D.S.Z., D.E.N.-T., A.K.), Otolaryngology-Head and Neck Surgery (D.R.G., D.S.Z., D.E.N.-T., A.K.), Ophthalmology (D.R.G., D.S.Z., D.E.N.-T.), Emergency Medicine (D.R.G.), Neurosurgery & Medicine (D.R.G.), and Neuroscience (D.S.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and School of Optometry (J.O.-M.), University of California, Berkeley
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Lädrach C, Zee DS, Wyss T, Wimmer W, Korda A, Salmina C, Caversaccio MD, Mantokoudis G. Alexander's Law During High-Speed, Yaw-Axis Rotation: Adaptation or Saturation? Front Neurol 2020; 11:604502. [PMID: 33329363 PMCID: PMC7719745 DOI: 10.3389/fneur.2020.604502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 10/02/2020] [Indexed: 11/13/2022] Open
Abstract
Objective: Alexander's law (AL) states the intensity of nystagmus increases when gaze is toward the direction of the quick phase. What might be its cause? A gaze-holding neural integrator (NI) that becomes imperfect as the result of an adaptive process, or saturation in the discharge of neurons in the vestibular nuclei? Methods: We induced nystagmus in normal subjects using a rapid chair acceleration around the yaw (vertical) axis to a constant velocity of 200°/second [s] and then, 90 s later, a sudden stop to induce post-rotatory nystagmus (PRN). Subjects alternated gaze every 2 s between flashing LEDs (right/left or up/down). We calculated the change in slow-phase velocity (ΔSPV) between right and left gaze when the lateral semicircular canals (SCC) were primarily stimulated (head upright) or, with the head tilted to the side, stimulating the vertical and lateral SCC together. Results: During PRN AL occurred for horizontal eye movements with the head upright and for both horizontal and vertical components of eye movements with the head tilted. AL was apparent within just a few seconds of the chair stopping when peak SPV of PRN was reached. When slow-phase velocity of PRN faded into the range of 6-18°/s AL could no longer be demonstrated. Conclusions: Our results support the idea that AL is produced by asymmetrical responses within the vestibular nuclei impairing the NI, and not by an adaptive response that develops over time. AL was related to the predicted plane of eye rotations in the orbit based on the pattern of SCC activation.
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Affiliation(s)
- Claudia Lädrach
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital Bern, Bern, Switzerland
| | - David S Zee
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Thomas Wyss
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital Bern, Bern, Switzerland
| | - Wilhelm Wimmer
- Hearing Research Laboratory, ARTORG Center, University of Bern, Bern, Switzerland
| | - Athanasia Korda
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital Bern, Bern, Switzerland
| | - Cinzia Salmina
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital Bern, Bern, Switzerland
| | - Marco D Caversaccio
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital Bern, Bern, Switzerland
| | - Georgios Mantokoudis
- Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital Bern, Bern, Switzerland
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Schubert MC, Helminski J, Zee DS, Cristiano E, Giannone A, Tortoriello G, Marcelli V. Horizontal semicircular canal jam: Two new cases and possible mechanisms. Laryngoscope Investig Otolaryngol 2020; 5:163-167. [PMID: 32128444 PMCID: PMC7042637 DOI: 10.1002/lio2.352] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/15/2019] [Accepted: 12/24/2019] [Indexed: 11/05/2022] Open
Abstract
INTRODUCTION Benign paroxysmal positional vertigo (BPPV) of the horizontal semicircular canal (hSCC) can present with otoconia blocking its lumen (canalith jam), with signs and symptoms that make it difficult to distinguish from central nervous system pathology. OBJECTIVE Here we report two cases of canalith jam affecting the hSCC and offer a theoretical mechanism based on known vestibular neurophysiology. METHODS We use video-oculography to document the canalith jam and show the moment the otoconia loosen. RESULTS Canalith jam is a rare form of BPPV remedied with repositioning maneuvers. CONCLUSION Clinicians should consider canalith jam as a mechanism for BPPV when the nystagmus is (a) Direction fixed with fixation removed and during positional testing; (b) Velocity dependent on supine head position; (c) Converts to geotropic directional changing nystagmus.
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Affiliation(s)
- Michael C. Schubert
- Laboratory of Vestibular NeuroAdaptation, Department of Otolaryngology ‐ Head and Neck SurgeryThe Johns Hopkins University School of MedicineBaltimoreMaryland
- Department of Physical Medicine and Rehabilitation BaltimoreThe Johns Hopkins University School of MedicineBaltimoreMaryland
| | - Janet Helminski
- Physical Therapy ProgramMidwestern UniversityDowners GroveIllinois
| | - David S. Zee
- Laboratory of Vestibular NeuroAdaptation, Department of Otolaryngology ‐ Head and Neck SurgeryThe Johns Hopkins University School of MedicineBaltimoreMaryland
- Department of NeurologyThe Johns Hopkins University School of MedicineBaltimoreMaryland
- Department of NeuroscienceThe Johns Hopkins University School of MedicineBaltimoreMaryland
- Department of OphthalmologyThe Johns Hopkins University School of MedicineBaltimoreMaryland
| | - Elisabetta Cristiano
- Department of OtolaryngologyAntonio Cardarelli National Relief HospitalNaplesItaly
| | - Antonio Giannone
- Department of OtolaryngologyAntonio Cardarelli National Relief HospitalNaplesItaly
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24
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Abstract
Benign paroxysmal positional vertigo (BPPV) is common, sometimes terrifying, but rarely portends serious disease. It is usually easily diagnosed and treated, and both the patient and the physician are immediately gratified. While much has been learned about the pathogenesis of BPPV in the past decades, many of its features remain mysterious, and one must still be wary of the rare times it mimics a dangerous brain disorder. Here we review common, relatively well understood clinical features of BPPV but also emphasize what we do not know and when the physician must look deeper for a more ominous cause.
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Affiliation(s)
- Daniele Nuti
- Department of Otology and Skull Base Surgery, University of Siena, Siena, Italy
| | - David S Zee
- Department of Neurology, Johns Hopkins Hospital, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Ophthalmology, Johns Hopkins Hospital, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Otolaryngology - Head and Neck Surgery, Johns Hopkins Hospital, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Neuroscience, Johns Hopkins Hospital, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Marco Mandalà
- Department of Otology and Skull Base Surgery, University of Siena, Siena, Italy
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25
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Abstract
The pathophysiology of acute, vertical spontaneous eye movements following pontine hemorrhage is not well understood. Here, we present and discuss the video-oculography findings of a patient with acute pontine hemorrhage who developed vertical pendular oscillation and ocular bobbing while comatose. The amplitudes, peak velocities, frequency distribution, and phase planes (velocity versus position) of the eye movements were analyzed. The vertical pendular oscillation was rhythmic with a peak frequency of 1.7 Hz, but amplitudes (mean 1.9°, range 0.2-8.2°) and peak velocities (mean 20.6°/s; range 5.9-60.6°/sec) fluctuated. Overall, their peak velocities were asymmetric, faster with downward than upward. Higher peak velocities were seen with larger amplitudes (downward phase r = 0.95, p < 0.001; upward phase r = 0.91, p < 0.001) and with movements beginning at eye positions lower in the orbit (downward phase r = - 0.64, p < 0.001; upward phase r = - 0.86, p < 0.001). Interspersed were typical ocular bobbing waveforms with a fast (peak velocity 128.8°/s), large-amplitude (17.5°) downward movement, sometimes followed by a flat interphase interval (0.5 s) when the eye was nearly stationary, and then a slow return to mid-position with a decaying velocity waveform. To account for the presence and co-existence of pendular oscillations and bobbing, we present and discuss three hypothetical models, not necessarily mutually exclusive: (1) oscillations originating in the inferior olives due to disruption of the central tegmental tract(s); (2) unstable neural integrator function due to pontine cell group damage involving neurons involved in gaze-holding; (3) low-frequency saccadic intrusions following omnipause neuron damage.
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Affiliation(s)
- Tzu-Pu Chang
- Department of Neurology, Neuro-medical Scientific Center, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, No. 88, Sec.1, Fengxing Rd., Tanzi Dist., Taichung City, 42743, Taiwan.,Department of Neurology, School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Daniel R Gold
- Department of Neurology, Johns Hopkins University School of Medicine, 600 N. Wolfe St Pathology 2-210, Baltimore, MD, 21287, USA
| | - Jorge Otero-Millan
- Department of Neurology, Johns Hopkins University School of Medicine, 600 N. Wolfe St Pathology 2-210, Baltimore, MD, 21287, USA
| | - Bor-Ren Huang
- Department of Neurosurgery, Neuro-medical Scientific Center, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung, Taiwan.,Department of Neurosurgery, School of Medicine, Tzu Chi University, No. 88, Sec.1, Fengxing Rd., Tanzi Dist, Taichung City, 42743, Taiwan
| | - David S Zee
- Department of Neurology, Johns Hopkins University School of Medicine, 600 N. Wolfe St Pathology 2-210, Baltimore, MD, 21287, USA.
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Kattah JC, Tehrani AS, du Lac S, Newman-Toker DE, Zee DS. Conversion of upbeat to downbeat nystagmus in Wernicke encephalopathy. Neurology 2019; 91:790-796. [PMID: 30348852 DOI: 10.1212/wnl.0000000000006385] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 06/27/2018] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To explain (1) why an initial upbeat nystagmus (UBN) converts to a permanent downbeat nystagmus (DBN) in Wernicke encephalopathy (WE) and (2) why convergence and certain vestibular provocative maneuvers may transiently switch UBN to DBN. METHODS Following a literature review and study of our 2 patients, we develop hypotheses for the unusual patterns of vertical nystagmus in WE. RESULTS Our overarching hypothesis is that there is a selective vulnerability and a selective recovery from thiamine deficiency of neurons within brainstem gaze-holding networks. Furthermore, since the circuits affected in WE are commonly paraventricular, especially medially, just under the floor of the fourth ventricle where lie structures important for control of vertical gaze, we suggest the patterns of involvement in WE also reflect a breakdown in vulnerable areas of the blood-brain barrier. Many of the initial deficits of our patients improved over time, but their DBN did not. Irreversible changes in paramedian tract neurons, which project to the cerebellar flocculus, may be the cause. Here we suggest that conversion of UBN to permanent DBN points to thiamine deficiency and may argue for a chronic, nonprogressive DBN/truncal ataxia syndrome. Finally, we posit that the transient switch of UBN to DBN reflects abnormal processing of otolith information about linear acceleration, and often points to a diagnosis of WE. CONCLUSION Recognizing the unusual patterns of transient switching and then permanent conversion of UBN to DBN in WE is vital since long-term disability from WE may be prevented by timely, parenteral high-dose thiamine.
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Affiliation(s)
- Jorge C Kattah
- From the Department of Neurology (J.C.K., A.S.T.), University of Illinois College of Medicine; Illinois Neurologic Institute (J.C.K., A.S.T.), Peoria; Departments of Otolaryngology-Head and Neck Surgery (S.d.L., D.E.N.-T., D.S.Z.), Neuroscience (S.d.L., D.E.N.-T., D.S.Z.), and Neurology (S.d.L., D.E.N.-T., D.S.Z.), and Division of Neuro-Visual & Vestibular Disorders (D.E.N.-T.), Johns Hopkins University, Baltimore, MD.
| | - Ali Saber Tehrani
- From the Department of Neurology (J.C.K., A.S.T.), University of Illinois College of Medicine; Illinois Neurologic Institute (J.C.K., A.S.T.), Peoria; Departments of Otolaryngology-Head and Neck Surgery (S.d.L., D.E.N.-T., D.S.Z.), Neuroscience (S.d.L., D.E.N.-T., D.S.Z.), and Neurology (S.d.L., D.E.N.-T., D.S.Z.), and Division of Neuro-Visual & Vestibular Disorders (D.E.N.-T.), Johns Hopkins University, Baltimore, MD
| | - Sascha du Lac
- From the Department of Neurology (J.C.K., A.S.T.), University of Illinois College of Medicine; Illinois Neurologic Institute (J.C.K., A.S.T.), Peoria; Departments of Otolaryngology-Head and Neck Surgery (S.d.L., D.E.N.-T., D.S.Z.), Neuroscience (S.d.L., D.E.N.-T., D.S.Z.), and Neurology (S.d.L., D.E.N.-T., D.S.Z.), and Division of Neuro-Visual & Vestibular Disorders (D.E.N.-T.), Johns Hopkins University, Baltimore, MD
| | - David E Newman-Toker
- From the Department of Neurology (J.C.K., A.S.T.), University of Illinois College of Medicine; Illinois Neurologic Institute (J.C.K., A.S.T.), Peoria; Departments of Otolaryngology-Head and Neck Surgery (S.d.L., D.E.N.-T., D.S.Z.), Neuroscience (S.d.L., D.E.N.-T., D.S.Z.), and Neurology (S.d.L., D.E.N.-T., D.S.Z.), and Division of Neuro-Visual & Vestibular Disorders (D.E.N.-T.), Johns Hopkins University, Baltimore, MD
| | - David S Zee
- From the Department of Neurology (J.C.K., A.S.T.), University of Illinois College of Medicine; Illinois Neurologic Institute (J.C.K., A.S.T.), Peoria; Departments of Otolaryngology-Head and Neck Surgery (S.d.L., D.E.N.-T., D.S.Z.), Neuroscience (S.d.L., D.E.N.-T., D.S.Z.), and Neurology (S.d.L., D.E.N.-T., D.S.Z.), and Division of Neuro-Visual & Vestibular Disorders (D.E.N.-T.), Johns Hopkins University, Baltimore, MD
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27
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Eggers SD, Bisdorff A, von Brevern M, Zee DS, Kim JS, Perez-Fernandez N, Welgampola MS, Della Santina CC, Newman-Toker DE. Classification of vestibular signs and examination techniques: Nystagmus and nystagmus-like movements. J Vestib Res 2019; 29:57-87. [PMID: 31256095 PMCID: PMC9249296 DOI: 10.3233/ves-190658] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This paper presents a classification and definitions for types of nystagmus and other oscillatory eye movements relevant to evaluation of patients with vestibular and neurological disorders, formulated by the Classification Committee of the Bárány Society, to facilitate identification and communication for research and clinical care. Terminology surrounding the numerous attributes and influencing factors necessary to characterize nystagmus are outlined and defined. The classification first organizes the complex nomenclature of nystagmus around phenomenology, while also considering knowledge of anatomy, pathophysiology, and etiology. Nystagmus is distinguished from various other nystagmus-like movements including saccadic intrusions and oscillations. View accompanying videos at http://www.jvr-web.org/ICVD.html
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Affiliation(s)
| | - Alexandre Bisdorff
- Department of Neurology, Centre Hospitalier Emile Mayrisch, Esch-sur-Alzette, Luxembourg
| | - Michael von Brevern
- Private Practice of Neurology and Department of Neurology, Charité, Berlin, Germany
| | - David S. Zee
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ji-Soo Kim
- Department of Neurology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seoul, Korea
| | | | - Miriam S. Welgampola
- Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Central Clinical School, University of Sydney, Sydney, Australia
| | - Charles C. Della Santina
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - David E. Newman-Toker
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Abstract
The study of eye movements not only addresses debilitating neuro-ophthalmological problems but has become an essential tool of basic neuroscience research. Eye movements are a classic way to evaluate brain function-traditionally in disorders affecting the brainstem and cerebellum. Abnormalities of eye movements have localizing value and help narrow the differential diagnosis of complex neurological problems. More recently, using sophisticated behavioral paradigms, measurement of eye movements has also been applied to disorders of the thalamus, basal ganglia, and cerebral cortex. Moreover, in contemporary neuroscience, eye movements play a key role in understanding cognition, behavior, and disorders of the mind. Examples include applications to higher-level decision-making processes as in neuroeconomics and psychiatric and cognitive disorders such as schizophrenia and autism. Eye movements have become valued as objective biomarkers to monitor the natural progression of disease and the effects of therapies. As specific genetic defects are identified for many neurological disorders, ocular motor function often becomes the cornerstone of phenotypic classification and differential diagnosis. Here, we introduce other important applications of eye movement research, including understanding movement disorders affecting the head and limbs. We also emphasize the need to develop standardized test batteries for eye movements of all types including the vestibulo-ocular responses. The evaluation and treatment of patients with cerebellar ataxia are particularly amenable to such an approach.
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Affiliation(s)
- Aasef G Shaikh
- Neurological Institute, University Hospitals Health System, Cleveland, OH, USA. .,Neurology Service, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, USA. .,Department of Neurology, Case Western Reserve University, 11100 Euclid Avenue, Cleveland, OH, 44110, USA.
| | - David S Zee
- Department of Neuroscience, The Johns Hopkins University, Baltimore, MD, USA.,Department of Neurology, The Johns Hopkins University, Baltimore, MD, USA.,Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University, Baltimore, MD, USA.,Department of Ophthalmology, The Johns Hopkins University, Baltimore, MD, USA
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29
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Beylergil SB, Singh AP, Zee DS, Jinnah HA, Shaikh AG. Relationship between jerky and sinusoidal oscillations in cervical dystonia. Parkinsonism Relat Disord 2019; 66:130-137. [PMID: 31345708 DOI: 10.1016/j.parkreldis.2019.07.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/17/2019] [Accepted: 07/20/2019] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Dystonia is often associated with repetitive jerky oscillations (i.e. dystonic tremor), while tremor is characterized by sinusoidal oscillations. We propose two competing predictions for dystonic tremor and sinusoidal tremor relationship. In any given patient, (1) the oscillation could be characterized as either sinusoidal or jerky based on the degree of distortion in the waveforms, (2) the oscillation consists of both sinusoidal and jerky waveforms mixed in a certain proportion that varies among individuals. We objectively test these predictions in patients with cervical dystonia. METHODS We recorded head oscillations in 14 subjects with cervical dystonia using a high-resolution magnetic field search coil system. Distortion in the signal was used as a measure of jerkiness. A hierarchical clustering classified the oscillations based on distortion characteristics. RESULTS Signal analysis in the frequency domain allowed identification of the components of the waveforms at frequencies other than the fundamental frequency. The distortion from the component at fundamental frequency was present in both low and high frequency range. Based on varying levels of distortions, i.e. jerkiness, the head oscillations were grouped into 4 clusters: one cluster with lowest distortion (sinusoidal waveforms), one cluster with highest distortion (jerky waveforms), and two intermediate clusters - one with distortion at low frequency and another with distortion at high frequency. The distribution of 4 clusters varied across subjects suggesting co-existence of sinusoidal and jerky waveforms. CONCLUSION These results support the prediction that jerky and sinusoidal waveforms concur in cervical dystonia. Amount of concurrence varies amongst patients.
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Affiliation(s)
- Sinem Balta Beylergil
- Department of Biomedical Engineering, Case Western University School of Medicine, Cleveland, OH, USA
| | - Aditya P Singh
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - David S Zee
- Department of Neurology, The Johns Hopkins University, Baltimore, MD, USA
| | - Hyder A Jinnah
- Departments of Neurology and Human Genetics, Emory University, Atlanta, GA, USA
| | - Aasef G Shaikh
- Department of Biomedical Engineering, Case Western University School of Medicine, Cleveland, OH, USA; Department of Neurology, Case Western University School of Medicine, Cleveland, OH, USA; Neurological Institute, University Hospitals, Cleveland, OH, USA; Neurology Service, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, USA.
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Rafehi H, Szmulewicz DJ, Bennett MF, Sobreira NLM, Pope K, Smith KR, Gillies G, Diakumis P, Dolzhenko E, Eberle MA, Barcina MG, Breen DP, Chancellor AM, Cremer PD, Delatycki MB, Fogel BL, Hackett A, Halmagyi GM, Kapetanovic S, Lang A, Mossman S, Mu W, Patrikios P, Perlman SL, Rosemergy I, Storey E, Watson SRD, Wilson MA, Zee DS, Valle D, Amor DJ, Bahlo M, Lockhart PJ. Bioinformatics-Based Identification of Expanded Repeats: A Non-reference Intronic Pentamer Expansion in RFC1 Causes CANVAS. Am J Hum Genet 2019; 105:151-165. [PMID: 31230722 PMCID: PMC6612533 DOI: 10.1016/j.ajhg.2019.05.016] [Citation(s) in RCA: 130] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 05/21/2019] [Indexed: 01/28/2023] Open
Abstract
Genomic technologies such as next-generation sequencing (NGS) are revolutionizing molecular diagnostics and clinical medicine. However, these approaches have proven inefficient at identifying pathogenic repeat expansions. Here, we apply a collection of bioinformatics tools that can be utilized to identify either known or novel expanded repeat sequences in NGS data. We performed genetic studies of a cohort of 35 individuals from 22 families with a clinical diagnosis of cerebellar ataxia with neuropathy and bilateral vestibular areflexia syndrome (CANVAS). Analysis of whole-genome sequence (WGS) data with five independent algorithms identified a recessively inherited intronic repeat expansion [(AAGGG)exp] in the gene encoding Replication Factor C1 (RFC1). This motif, not reported in the reference sequence, localized to an Alu element and replaced the reference (AAAAG)11 short tandem repeat. Genetic analyses confirmed the pathogenic expansion in 18 of 22 CANVAS-affected families and identified a core ancestral haplotype, estimated to have arisen in Europe more than twenty-five thousand years ago. WGS of the four RFC1-negative CANVAS-affected families identified plausible variants in three, with genomic re-diagnosis of SCA3, spastic ataxia of the Charlevoix-Saguenay type, and SCA45. This study identified the genetic basis of CANVAS and demonstrated that these improved bioinformatics tools increase the diagnostic utility of WGS to determine the genetic basis of a heterogeneous group of clinically overlapping neurogenetic disorders.
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Affiliation(s)
- Haloom Rafehi
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia; Department of Medical Biology, University of Melbourne, 1G Royal Parade, Parkville, VIC 3052, Australia
| | - David J Szmulewicz
- Cerebellar Ataxia Clinic, Neuroscience Department, Alfred Health, Melbourne, VIC 3004, Australia; Balance Disorders and Ataxia Service, Royal Victorian Eye & Ear Hospital, East Melbourne, VIC 3002, Australia
| | - Mark F Bennett
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia; Department of Medical Biology, University of Melbourne, 1G Royal Parade, Parkville, VIC 3052, Australia; Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, 245 Burgundy Street, Heidelberg, VIC 3084, Australia
| | - Nara L M Sobreira
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Kate Pope
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia
| | - Katherine R Smith
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia
| | - Greta Gillies
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia
| | - Peter Diakumis
- University of Melbourne Centre for Cancer Research, Victorian Comprehensive Cancer Centre, 305 Grattan Street, Melbourne, VIC 3000, Australia
| | - Egor Dolzhenko
- Illumina Inc, 5200 Illumina Way, San Diego, CA 92122, USA
| | | | - María García Barcina
- Genetic Unit, Basurto University Hospital, OSI Bilbao-Basurto, avenida Montevideo 18, 48013 Bilbao, Spain
| | - David P Breen
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, Scotland; Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh EH16 4SB, Scotland; Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh EH16 4UX, Scotland
| | - Andrew M Chancellor
- Department of Neurology, Tauranga Hospital, Private Bag, Cameron Road, Tauranga 3171, New Zealand
| | - Phillip D Cremer
- University of Sydney, Camperdown, NSW 2006, Australia; Royal North Shore Hospital, Pacific Hwy, St Leonards, NSW 2065, Australia
| | - Martin B Delatycki
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia; Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Flemington Rd, Parkville, VIC 3052, Australia
| | - Brent L Fogel
- Departments of Neurology and Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Anna Hackett
- Hunter Genetics, Hunter New England Health Service, Waratah, Newcastle, NSW 2300, Australia; University of Newcastle, Newcastle, NSW 2300, Australia
| | - G Michael Halmagyi
- Neurology Department, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia; Central Clinical School, University of Sydney, Camperdown, NSW 2050, Australia
| | - Solange Kapetanovic
- Servicio de Neurología, Hospital de Basurto, Avenida de Montevideo 18, 48013 Bilbao, Bizkaia, Spain
| | - Anthony Lang
- Edmond J. Safra Program in Parkinson disease and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON M5T 2S8, Canada; Department of Medicine, Division of Neurology, University Health Network and the University of Toronto, Toronto, ON M5T 2S8, Canada
| | - Stuart Mossman
- Department of Neurology, Wellington Hospital, Wellington 6021, New Zealand
| | - Weiyi Mu
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | | | - Susan L Perlman
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Ian Rosemergy
- Department of Neurology, Wellington Hospital, Newtown, Wellington 6021, New Zealand
| | - Elsdon Storey
- Department of Neuroscience, Central Clinical School, Monash University, Alfred Hospital Campus, Commercial Road, Melbourne, VIC 3004, Australia
| | - Shaun R D Watson
- Institute of Neurological Sciences, Prince of Wales Hospital, Randwick, NSW 2031, Australia
| | - Michael A Wilson
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia
| | - David S Zee
- Department of Neurology, Johns Hopkins Hospital, Baltimore, MD 21287, USA
| | - David Valle
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - David J Amor
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia; Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Flemington Rd, Parkville, VIC 3052, Australia
| | - Melanie Bahlo
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia; Department of Medical Biology, University of Melbourne, 1G Royal Parade, Parkville, VIC 3052, Australia
| | - Paul J Lockhart
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia; Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Flemington Rd, Parkville, VIC 3052, Australia.
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Choi JY, Glasauer S, Kim JH, Zee DS, Kim JS. Characteristics and mechanism of apogeotropic central positional nystagmus. Brain 2019; 141:762-775. [PMID: 29373699 DOI: 10.1093/brain/awx381] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 11/23/2017] [Indexed: 11/12/2022] Open
Abstract
Here we characterize persistent apogeotropic type of central positional nystagmus, and compare it with the apogeotropic nystagmus of benign paroxysmal positional vertigo involving the lateral canal. Nystagmus was recorded in 27 patients with apogeotropic type of central positional nystagmus (22 with unilateral and five with diffuse cerebellar lesions) and 20 patients with apogeotropic nystagmus of benign paroxysmal positional vertigo. They were tested while sitting, while supine with the head straight back, and in the right and left ear-down positions. The intensity of spontaneous nystagmus was similar while sitting and supine in apogeotropic type of central positional nystagmus, but greater when supine in apogeotropic nystagmus of benign paroxysmal positional vertigo. In central positional nystagmus, when due to a focal pathology, the lesions mostly overlapped in the vestibulocerebellum (nodulus, uvula, and tonsil). We suggest a mechanism for apogeotropic type of central positional nystagmus based on the location of lesions and a model that uses the velocity-storage mechanism. During both tilt and translation, the otolith organs can relay the same gravito-inertial acceleration signal. This inherent ambiguity can be resolved by a 'tilt-estimator circuit' in which information from the semicircular canals about head rotation is combined with otolith information about linear acceleration through the velocity-storage mechanism. An example of how this mechanism works in normal subjects is the sustained horizontal nystagmus that is produced when a normal subject is rotated at a constant speed around an axis that is tilted away from the true vertical (off-vertical axis rotation). We propose that when the tilt-estimator circuit malfunctions, for example, with lesions in the vestibulocerebellum, the estimate of the direction of gravity is erroneously biased away from true vertical. If the bias is toward the nose, when the head is turned to the side while supine, there will be sustained, unwanted, horizontal positional nystagmus (apogeotropic type of central positional nystagmus) because of an inappropriate feedback signal indicating that the head is rotating when it is not.
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Affiliation(s)
- Jeong-Yoon Choi
- Department of Neurology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Stefan Glasauer
- Center for Sensorimotor Research, Department of Neurology, Ludwig-Maximilian University Munich, Munich, Germany.,German Center for Vertigo and Balance Disorders, Ludwig-Maximilian University Munich, Munich, Germany
| | - Ji Hyun Kim
- Department of Neurology, Korea University College of Medicine, Korea University Guro Hospital, Seoul, Korea
| | - David S Zee
- Departments of Neurology, Ophthalmology, Otolaryngology - Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ji-Soo Kim
- Department of Neurology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
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Yacovino DA, Akly MP, Luis L, Zee DS. The Floccular Syndrome: Dynamic Changes in Eye Movements and Vestibulo-ocular Reflex in Isolated Infarction of the Cerebellar Flocculus. Cerebellum 2019; 17:122-131. [PMID: 28844105 DOI: 10.1007/s12311-017-0878-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The cerebellar flocculus is a critical structure involved in the control of eye movements. Both static and dynamic abnormalities of the vestibulo-ocular reflex (VOR) have been described in animals with experimental lesions of the flocculus/paraflocculus complex. In humans, lesions restricted to the flocculus are rare so they can become an exceptional model to contrast with the clinical features in experimental animals or in patients with more generalized cerebellar diseases. Here, we examined a 67-year-old patient with an acute vestibular syndrome due to an isolated infarct of the right flocculus. We evaluated him multiple times over 6 months-to follow the changes in eye movements and vestibular function-with caloric testing, video-oculography and head-impulse testing, and the anatomical changes on imaging. Acutely, he had an ipsilateral-beating spontaneous nystagmus, bilateral gaze-evoked nystagmus, borderline impaired smooth pursuit, and a complete contraversive ocular tilt reaction. The VOR gain was reduced for head impulses directed contralateral to the lesion, and there was also an ipsilesional caloric weakness. All abnormalities progressively improved at follow-up visits but with a considerable reduction in volume of the affected flocculus on imaging. The vestibular and ocular motor findings, qualitatively similar to a previously reported patient, further clarify the "acute floccular syndrome" in humans. We also add new information about the pattern of recovery from such a lesion with corresponding changes in the size of the affected flocculus on imaging.
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Affiliation(s)
- Dario Andres Yacovino
- Department of Neurology, Dr. Cesar Milstein Hospital, Buenos Aires, Argentina.
- Memory and Balance Clinic, Buenos Aires, Argentina.
| | - Manuel Perez Akly
- Department of Neuroradiology, Dr. Cesar Milstein Hospital, Buenos Aires, Argentina
- Department of Radiology, Italian Hospital, Buenos Aires, Argentina
| | - Leonel Luis
- Department of Otolaryngology, Hospital Santa Maria, CHLN, Lisbon, Portugal
| | - David S Zee
- Departments of Neurology, Otolaryngology-Head and Neck Surgery, Ophthalmology and Neuroscience, Johns Hopkins Hospital, Baltimore, MD, USA
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33
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Rizzo JR, Hudson TE, Sequeira AJ, Dai W, Chaudhry Y, Martone J, Zee DS, Optican LM, Balcer LJ, Galetta SL, Rucker JC. Eye position-dependent opsoclonus in mild traumatic brain injury. Prog Brain Res 2019; 249:65-78. [PMID: 31325998 DOI: 10.1016/bs.pbr.2019.04.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
Opsoclonus consists of bursts of involuntary, multidirectional, back-to-back saccades without an intersaccadic interval. We report a 60-year-old man with post-concussive headaches and disequilibrium who had small amplitude opsoclonus in left gaze, along with larger amplitude flutter during convergence. Examination was otherwise normal and brain MRI was unremarkable. Video-oculography demonstrated opsoclonus predominantly in left gaze and during pursuit in the left hemifield, which improved as post-concussive symptoms improved. Existing theories of opsoclonus mechanisms do not account for this eye position-dependence. We discuss theoretical mechanisms of this behavior, including possible dysfunction of frontal eye field and/or cerebellar vermis neurons; review ocular oscillations in traumatic brain injury; and consider the potential relationship between the larger amplitude flutter upon convergence and post-traumatic ocular oscillations.
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Affiliation(s)
- John-Ross Rizzo
- Department of Physical Medicine and Rehabilitation, New York University School of Medicine, New York, NY, United States; Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - Todd E Hudson
- Department of Physical Medicine and Rehabilitation, New York University School of Medicine, New York, NY, United States; Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - Alexandra J Sequeira
- Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - Weiwei Dai
- Department of Neurology, New York University School of Medicine, New York, NY, United States; Department of Electrical and Computer Engineering, New York University Tandon School of Engineering, New York, NY, United States
| | - Yash Chaudhry
- Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - John Martone
- Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - David S Zee
- Department of Neurology, The Johns Hopkins University, Baltimore, MD, United States
| | - Lance M Optican
- Laboratory of Sensorimotor Research, NEI, NIH, DHHS, Bethesda, MD, United States
| | - Laura J Balcer
- Department of Neurology, New York University School of Medicine, New York, NY, United States; Department of Ophthalmology, New York University School of Medicine, New York, NY, United States; Department of Population Health, New York University School of Medicine, New York, NY, United States
| | - Steven L Galetta
- Department of Neurology, New York University School of Medicine, New York, NY, United States; Department of Ophthalmology, New York University School of Medicine, New York, NY, United States
| | - Janet C Rucker
- Department of Neurology, New York University School of Medicine, New York, NY, United States; Department of Ophthalmology, New York University School of Medicine, New York, NY, United States.
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34
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Srivastava S, Butala A, Mahida S, Richter J, Mu W, Poretti A, Vernon H, VanGerpen J, Atwal PS, Middlebrooks EH, Zee DS, Naidu S. Expansion of the clinical spectrum associated with AARS2-related disorders. Am J Med Genet A 2019; 179:1556-1564. [PMID: 31099476 DOI: 10.1002/ajmg.a.61188] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/21/2019] [Accepted: 04/23/2019] [Indexed: 12/14/2022]
Abstract
Biallelic pathogenic variants in AARS2, a gene encoding the mitochondrial alanyl-tRNA synthetase, result in a spectrum of findings ranging from infantile cardiomyopathy to adult-onset progressive leukoencephalopathy. In this article, we present three unrelated individuals with novel compound heterozygous pathogenic AARS2 variants underlying diverse clinical presentations. Patient 1 is a 51-year-old man with adult-onset progressive cognitive, psychiatric, and motor decline and leukodystrophy. Patient 2 is a 34-year-old man with childhood-onset progressive tremor followed by the development of polyneuropathy, ataxia, and mild cognitive and psychiatric decline without leukodystrophy on imaging. Patient 3 is a 57-year-old woman with childhood-onset tremor and nystagmus which preceded dystonia, chorea, ataxia, depression, and cognitive decline marked by cerebellar atrophy and white matter disease. These cases expand the clinical heterogeneity of AARS2-related disorders, given that the first and third case represent some of the oldest known survivors of this disease, the second is adult-onset AARS2-related neurological decline without leukodystrophy, and the third is biallelic AARS2-related disorder involving a partial gene deletion.
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Affiliation(s)
| | - Ankur Butala
- Department of Neurology, The Johns Hopkins Hospital, Baltimore, Maryland
| | - Sonal Mahida
- Department of Neurology, Boston Children's Hospital, Boston, Massachusetts
| | - John Richter
- Department of Neurology, Mayo Clinic, Jacksonville, Florida
| | - Weiyi Mu
- Institute of Genetic Medicine, The Johns Hopkins Hospital, Baltimore, Maryland
| | - Andrea Poretti
- Department of Neurogenetics, Hugo W. Moser Research Institute at Kennedy Krieger Institute, Baltimore, Maryland.,Department of Neurology and Pediatrics, The Johns Hopkins Hospital, Baltimore, Maryland
| | - Hilary Vernon
- Institute of Genetic Medicine, The Johns Hopkins Hospital, Baltimore, Maryland
| | - Jay VanGerpen
- Department of Neurology, Mayo Clinic, Jacksonville, Florida
| | | | - Erik H Middlebrooks
- Department of Radiology and Neurosurgery, Mayo Clinic, Jacksonville, Florida
| | - David S Zee
- Department of Neurology, The Johns Hopkins Hospital, Baltimore, Maryland.,Department of Ophthalmology, Otolaryngology, Head and Neck Surgery and Neuroscience, The Johns Hopkins Hospital, Baltimore, Maryland
| | - SakkuBai Naidu
- Department of Neurogenetics, Hugo W. Moser Research Institute at Kennedy Krieger Institute, Baltimore, Maryland.,Department of Neurology and Pediatrics, The Johns Hopkins Hospital, Baltimore, Maryland
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35
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Kattah JC, McClelland C, Zee DS. Vertical nystagmus in Wernicke’s encephalopathy: pathogenesis and role of central processing of information from the otoliths. J Neurol 2019; 266:139-145. [DOI: 10.1007/s00415-019-09326-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/11/2019] [Accepted: 04/13/2019] [Indexed: 11/30/2022]
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Ward BK, Roberts DC, Otero-Millan J, Zee DS. A decade of magnetic vestibular stimulation: from serendipity to physics to the clinic. J Neurophysiol 2019; 121:2013-2019. [PMID: 30969883 DOI: 10.1152/jn.00873.2018] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
For many years, people working near strong static magnetic fields of magnetic resonance imaging (MRI) machines have reported dizziness and sensations of vertigo. The discovery a decade ago that a sustained nystagmus can be observed in all humans with an intact labyrinth inside MRI machines led to a possible mechanism: a Lorentz force occurring in the labyrinth from the interactions of normal inner ear ionic currents and the strong static magnetic fields of the MRI machine. Inside an MRI, the Lorentz force acts to induce a constant deflection of the semicircular canal cupula of the superior and lateral semicircular canals. This inner ear stimulation creates a sensation of rotation, and a constant horizontal/torsional nystagmus that can only be observed when visual fixation is removed. Over time, the brain adapts to both the perception of rotation and the nystagmus, with the perception usually diminishing over a few minutes, and the nystagmus persisting at a reduced level for hours. This observation has led to discoveries about how the central vestibular mechanisms adapt to a constant vestibular asymmetry and is a useful model of set-point adaptation or how homeostasis is maintained in response to changes in the internal milieu or the external environment. We review what is known about the effects of stimulation of the vestibular system with high-strength magnetic fields and how the understanding of the mechanism has been refined since it was first proposed. We suggest future ways that magnetic vestibular stimulation might be used to understand vestibular disease and how it might be treated.
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Affiliation(s)
- Bryan K Ward
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - Dale C Roberts
- Department of Neurology, The Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - Jorge Otero-Millan
- Department of Neurology, The Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - David S Zee
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University School of Medicine , Baltimore, Maryland.,Department of Neurology, The Johns Hopkins University School of Medicine , Baltimore, Maryland.,Department of Neuroscience, The Johns Hopkins University School of Medicine , Baltimore, Maryland.,Department of Ophthalmology, The Johns Hopkins University School of Medicine , Baltimore, Maryland
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Ward BK, Zee DS, Roberts DC, Schubert MC, Pérez-Fernández N, Otero-Millan J. Visual Fixation and Continuous Head Rotations Have Minimal Effect on Set-Point Adaptation to Magnetic Vestibular Stimulation. Front Neurol 2019; 9:1197. [PMID: 30723456 PMCID: PMC6349782 DOI: 10.3389/fneur.2018.01197] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Accepted: 12/31/2018] [Indexed: 11/13/2022] Open
Abstract
Background: Strong static magnetic fields such as those in an MRI machine can induce sensations of self-motion and nystagmus. The proposed mechanism is a Lorentz force resulting from the interaction between strong static magnetic fields and ionic currents in the inner ear endolymph that causes displacement of the semicircular canal cupulae. Nystagmus persists throughout an individual's exposure to the magnetic field, though its slow-phase velocity partially declines due to adaptation. After leaving the magnetic field an after effect occurs in which the nystagmus and sensations of rotation reverse direction, reflecting the adaptation that occurred while inside the MRI. However, the effects of visual fixation and of head shaking on this early type of vestibular adaptation are unknown. Methods: Three-dimensional infrared video-oculography was performed in six individuals just before, during (5, 20, or 60 min) and after (4, 15, or 20 min) lying supine inside a 7T MRI scanner. Trials began by entering the magnetic field in darkness followed 60 s later, either by light with visual fixation and head still, or by continuous yaw head rotations (2 Hz) in either darkness or light with visual fixation. Subjects were always placed in darkness 10 or 30 s before exiting the bore. In control conditions subjects remained in the dark with the head still for the entire duration. Results: In darkness with head still all subjects developed horizontal nystagmus inside the magnetic field, with slow-phase velocity partially decreasing over time. An after effect followed on exiting the magnet, with nystagmus in the opposite direction. Nystagmus was suppressed during visual fixation; however, after resuming darkness just before exiting the magnet, nystagmus returned with velocity close to the control condition and with a comparable after effect. Similar after effects occurred with continuous yaw head rotations while in the scanner whether in darkness or light. Conclusions: Visual fixation and sustained head shaking either in the dark or with fixation inside a strong static magnetic field have minimal impact on the short-term mechanisms that attempt to null unwanted spontaneous nystagmus when the head is still, so called VOR set-point adaptation. This contrasts with the critical influence of vision and slippage of images on the retina on the dynamic (gain and direction) components of VOR adaptation.
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Affiliation(s)
- Bryan K Ward
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University, Baltimore, MD, United States
| | - David S Zee
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University, Baltimore, MD, United States.,Department of Neurology, The Johns Hopkins University, Baltimore, MD, United States.,Department of Neuroscience, The Johns Hopkins University, Baltimore, MD, United States.,Department of Ophthalmology, The Johns Hopkins University, Baltimore, MD, United States
| | - Dale C Roberts
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University, Baltimore, MD, United States.,Department of Neurology, The Johns Hopkins University, Baltimore, MD, United States
| | - Michael C Schubert
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University, Baltimore, MD, United States.,Department of Physical Medicine and Rehabilitation, The Johns Hopkins University, Baltimore, MD, United States
| | | | - Jorge Otero-Millan
- Department of Neurology, The Johns Hopkins University, Baltimore, MD, United States
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Leigh RJ, Zee DS. Mathematical models: An extension of the clinician's mind. Progress in Brain Research 2019; 248:19-26. [DOI: 10.1016/bs.pbr.2018.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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39
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Otero-Millan J, Colpak AI, Kheradmand A, Zee DS. Rebound nystagmus, a window into the oculomotor integrator. Progress in Brain Research 2019; 249:197-209. [DOI: 10.1016/bs.pbr.2019.04.040] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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40
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Sadeghpour S, Zee DS, Leigh RJ. Clinical applications of control systems models: The neural integrators for eye movements. Progress in Brain Research 2019; 248:103-114. [DOI: 10.1016/bs.pbr.2018.12.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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41
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Koens LH, Tijssen MAJ, Lange F, Wolffenbuttel BHR, Rufa A, Zee DS, de Koning TJ. Eye movement disorders and neurological symptoms in late-onset inborn errors of metabolism. Mov Disord 2018; 33:1844-1856. [PMID: 30485556 PMCID: PMC6587951 DOI: 10.1002/mds.27484] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 08/03/2018] [Accepted: 08/06/2018] [Indexed: 11/06/2022] Open
Abstract
Inborn errors of metabolism in adults are still largely unexplored. Despite the fact that adult‐onset phenotypes have been known for many years, little attention is given to these disorders in neurological practice. The adult‐onset presentation differs from childhood‐onset phenotypes, often leading to considerable diagnostic delay. The identification of these patients at the earliest stage of disease is important, given that early treatment may prevent or lessen further brain damage. Neurological and psychiatric symptoms occur more frequently in adult forms. Abnormalities of eye movements are also common and can be the presenting sign. Eye movement disorders can be classified as central or peripheral. Central forms are frequently observed in lysosomal storage disorders, whereas peripheral forms are a key feature of mitochondrial disease. Furthermore, oculogyric crisis is an important feature in disorders affecting dopamine syntheses or transport. Ocular motor disorders are often not reported by the patient, and abnormalities can be easily overlooked in a general examination. In adults with unexplained psychiatric and neurological symptoms, a special focus on examination of eye movements can serve as a relatively simple clinical tool to detect a metabolic disorder. Eye movements can be easily quantified and analyzed with video‐oculography, making them a valuable biomarker for following the natural course of disease or the response to therapies. Here, we review, for the first time, eye movement disorders that can occur in inborn errors of metabolism, with a focus on late‐onset forms. We provide a step‐by‐step overview that will help clinicians to examine and interpret eye movement disorders. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Lisette H Koens
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Marina A J Tijssen
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Fiete Lange
- University of Groningen, University Medical Center Groningen, Department of Clinical Neurophysiology, Groningen, The Netherlands
| | - Bruce H R Wolffenbuttel
- Department of Endocrinology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Alessandra Rufa
- Department of Medicine Surgery and Neurosciences, University of Siena, Eye tracking and Visual Application Lab (EVA Lab)-Neurology and Neurometabolic Unit, Siena, Italy
| | - David S Zee
- Department of Neuroscience, Department of Ophthalmology, The Johns Hopkins University, The Johns Hopkins Hospital, Department of Neurology, Department of Otolaryngology-Head and Neck Surgery, Baltimore, Maryland, USA
| | - Tom J de Koning
- University of Groningen, Division of Metabolic Diseases, University Medical Center Groningen, Groningen, The Netherlands.,University of Groningen, Department of Genetics, University Medical Center Groningen, Groningen, The Netherlands
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Abstract
The phenotypic and genetic spectrum of ataxia with oculomotor apraxia (AOA) disorders is rapidly evolving and new technologies such as genetic mapping using whole exome sequencing reveal subtle distinctions among the various subtypes. We report a novel PNKP mutation in two siblings with progressive ataxia, abnormal saccades, sensorimotor neuropathy and dystonia consistent with the AOA type 4 phenotype. Laboratory evaluation revealed hypoalbuminemia, hypercholesterolemia with elevated LDL, elevated IgE levels and normal α fetoprotein levels. Eye movement examination demonstrated a marked saccade initiation defect with profound hypometric horizontal saccades. Vertical saccades were also affected but less so. Also present were conspicuous thrusting head movements when attempting to change gaze, but rather than an apraxia these were an adaptive strategy to take advantage of an intact vestibulo-ocular reflex to carry the eyes to a new target of interest. This is demonstrated in accompanying videos.
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Affiliation(s)
- Nicoline Schiess
- a Department of Neurology , Johns Hopkins Hospital , Baltimore , MD , USA
| | - David S Zee
- a Department of Neurology , Johns Hopkins Hospital , Baltimore , MD , USA
| | - Khurram A Siddiqui
- b Department of Neurology , Al Ain Hospital , Al Ain , United Arab Emirates
| | - Miklos Szolics
- c Department of Neurology , Tawam Hospital , Al Ain , United Arab Emirates
| | - Ayman W El-Hattab
- d Division of Clinical Genetics and Metabolic Disorders , Tawam Hospital , Al-Ain , United Arab Emirates
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Saber Tehrani AS, Kattah JC, Kerber KA, Gold DR, Zee DS, Urrutia VC, Newman-Toker DE. Diagnosing Stroke in Acute Dizziness and Vertigo: Pitfalls and Pearls. Stroke 2018; 49:788-795. [PMID: 29459396 PMCID: PMC5829023 DOI: 10.1161/strokeaha.117.016979] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/17/2017] [Accepted: 11/21/2017] [Indexed: 11/16/2022]
Affiliation(s)
- Ali S Saber Tehrani
- From the Department of Neuro-Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston (A.S.S.T.); Department of Neurology, University of Illinois College of Medicine in Peoria (J.C.K.); Department of Neurology, University of Michigan Health System, Ann Arbor (K.A.K.); and Department of Neurology (D.R.G., D.S.Z., D.E.N.-T.) and Department of Neurology, The Johns Hopkins Hospital Comprehensive Stroke Center (V.C.U.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Jorge C Kattah
- From the Department of Neuro-Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston (A.S.S.T.); Department of Neurology, University of Illinois College of Medicine in Peoria (J.C.K.); Department of Neurology, University of Michigan Health System, Ann Arbor (K.A.K.); and Department of Neurology (D.R.G., D.S.Z., D.E.N.-T.) and Department of Neurology, The Johns Hopkins Hospital Comprehensive Stroke Center (V.C.U.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Kevin A Kerber
- From the Department of Neuro-Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston (A.S.S.T.); Department of Neurology, University of Illinois College of Medicine in Peoria (J.C.K.); Department of Neurology, University of Michigan Health System, Ann Arbor (K.A.K.); and Department of Neurology (D.R.G., D.S.Z., D.E.N.-T.) and Department of Neurology, The Johns Hopkins Hospital Comprehensive Stroke Center (V.C.U.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Daniel R Gold
- From the Department of Neuro-Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston (A.S.S.T.); Department of Neurology, University of Illinois College of Medicine in Peoria (J.C.K.); Department of Neurology, University of Michigan Health System, Ann Arbor (K.A.K.); and Department of Neurology (D.R.G., D.S.Z., D.E.N.-T.) and Department of Neurology, The Johns Hopkins Hospital Comprehensive Stroke Center (V.C.U.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - David S Zee
- From the Department of Neuro-Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston (A.S.S.T.); Department of Neurology, University of Illinois College of Medicine in Peoria (J.C.K.); Department of Neurology, University of Michigan Health System, Ann Arbor (K.A.K.); and Department of Neurology (D.R.G., D.S.Z., D.E.N.-T.) and Department of Neurology, The Johns Hopkins Hospital Comprehensive Stroke Center (V.C.U.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Victor C Urrutia
- From the Department of Neuro-Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston (A.S.S.T.); Department of Neurology, University of Illinois College of Medicine in Peoria (J.C.K.); Department of Neurology, University of Michigan Health System, Ann Arbor (K.A.K.); and Department of Neurology (D.R.G., D.S.Z., D.E.N.-T.) and Department of Neurology, The Johns Hopkins Hospital Comprehensive Stroke Center (V.C.U.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - David E Newman-Toker
- From the Department of Neuro-Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston (A.S.S.T.); Department of Neurology, University of Illinois College of Medicine in Peoria (J.C.K.); Department of Neurology, University of Michigan Health System, Ann Arbor (K.A.K.); and Department of Neurology (D.R.G., D.S.Z., D.E.N.-T.) and Department of Neurology, The Johns Hopkins Hospital Comprehensive Stroke Center (V.C.U.), Johns Hopkins University School of Medicine, Baltimore, MD.
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Zee DS. A neurologist and ataxia: using eye movements to learn about the cerebellum. Cerebellum Ataxias 2018; 5:2. [PMID: 29445510 PMCID: PMC5804057 DOI: 10.1186/s40673-018-0081-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 01/25/2018] [Indexed: 11/22/2022]
Abstract
The cerebellum, its normal functions and its diseases, and especially its relation to the control of eye movements, has been at the heart of my academic career. Here I review how this came about, with an emphasis on epiphanies, "tipping points" and the influences of mentors, colleagues and trainees. I set a path for young academicians, both clinicians and basic scientists, with some guidelines for developing a productive and rewarding career in neuroscience.
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Affiliation(s)
- David S. Zee
- Departments of Neurology, Ophthalamology, Otolaryngology-Head and Neck Surgery, and Neuroscience, The Johns Hopkins University School of Medicine, The Johns Hopkins Hospital, Path 2-210, Baltimore, MD 21287 USA
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Mantokoudis G, Saber Tehrani AS, Wozniak A, Eibenberger K, Kattah JC, Guede CI, Zee DS, Newman-Toker DE. Impact of artifacts on VOR gain measures by video-oculography in the acute vestibular syndrome. J Vestib Res 2018; 26:375-385. [PMID: 27814312 DOI: 10.3233/ves-160587] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE The video head impulse test (HIT) measures vestibular function (vestibulo-ocular reflex [VOR] gain - ratio of eye to head movement), and, in principle, could be used to make a distinction between central and peripheral causes of vertigo. However, VOG recordings contain artifacts, so using unfiltered device data might bias the final diagnosis, limiting application in frontline healthcare settings such as the emergency department (ED). We sought to assess whether unfiltered data (containing artifacts) from a video-oculography (VOG) device have an impact on VOR gain measures in acute vestibular syndrome (AVS). METHODS This cross-sectional study compared VOG HIT results 'unfiltered' (standard device output) versus 'filtered' (artifacts manually removed) and relative to a gold standard final diagnosis (neuroimaging plus clinical follow-up) in 23 ED patients with acute dizziness, nystagmus, gait disturbance and head motion intolerance. RESULTS Mean VOR gain assessment alone (unfiltered device data) discriminated posterior inferior cerebellar artery (PICA) strokes from vestibular neuritis with 91% accuracy in AVS. Optimal stroke discrimination cut points were bilateral VOR gain >0.7099 (unfiltered data) versus >0.7041 (filtered data). For PICA stroke sensitivity and specificity, there was no clinically-relevant difference between unfiltered and filtered data-sensitivity for PICA stroke was 100% for both data sets and specificity was almost identical (87.5% unfiltered versus 91.7% filtered). More impulses increased gain precision. CONCLUSIONS The bedside HIT remains the single best method for discriminating between vestibular neuritis and PICA stroke in patients presenting AVS. Quantitative VOG HIT testing in the ED is associated with frequent artifacts that reduce precision but not accuracy. At least 10-20 properly-performed HIT trials per tested ear are recommended for a precise VOR gain estimate.
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Affiliation(s)
- Georgios Mantokoudis
- University Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital Bern, Switzerland.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ali S Saber Tehrani
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Amy Wozniak
- Johns Hopkins Biostatistics Center, Baltimore, MD, USA
| | - Karin Eibenberger
- Department of Otolaryngology - Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jorge C Kattah
- Department of Neurology, Illinois Neurologic Institute, University of Illinois, College of Medicine, Peoria, IL, USA
| | - Cynthia I Guede
- Department of Neurology, Illinois Neurologic Institute, University of Illinois, College of Medicine, Peoria, IL, USA
| | - David S Zee
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - David E Newman-Toker
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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47
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Oh EH, Lee JH, Shin JH, Kim HS, Kim JS, Kim HJ, Choi SY, Choi KD, Zee DS, Choi JH. Patterns and modulations of Pendular nystagmus in a family with hereditary spastic paraplegia. J Neurol Sci 2017; 383:169-173. [PMID: 29246608 DOI: 10.1016/j.jns.2017.11.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 10/20/2017] [Accepted: 11/14/2017] [Indexed: 11/19/2022]
Abstract
Hereditary spastic paraplegia (HSP) is characterized by progressive spasticity and weakness of the lower extremities. Additional findings include ataxia, extrapyramidal signs, and dementia. Pendular nystagmus (PN) has been reported in some subtypes of HSP caused by PLP1 (SPG2) or paraplegin (SPG7) mutation. To describe the patterns and modulation of PN in HSP, we performed eye movement recording using video-oculography in a Korean family with HSP and PN. The PN was convergent-divergent in the oblique plane with a frequency of 6 to 7Hz and maximum amplitude at about 1.5°. The nystagmus diminished briefly after blinks and horizontal saccades, and decreased during eccentric gaze and convergence. Horizontal saccades shifted the phase of the oscillations. During lateral gazes, the PN increased in the abducting eye, but decreased in the adducting eye. Vibratory stimuli decreased the nystagmus mostly in the left but not in the right eye. No pathogenic mutation was found in the genetic loci known for causing spastic paraplegia by whole-exome sequencing. The unusual features and modulation of PN in our patients with HSP emphasize the role of disconjugate and disjunctive capabilities of the brain in ocular motor control, and exemplify what can go wrong.
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Affiliation(s)
- Eun Hye Oh
- Department of Neurology, Pusan National University School of Medicine, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea
| | - Jae-Hyeok Lee
- Department of Neurology, Pusan National University School of Medicine, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea
| | - Jin-Hong Shin
- Department of Neurology, Pusan National University School of Medicine, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea
| | - Hyang-Sook Kim
- Department of Neurology, Pusan National University School of Medicine, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea
| | - Ji-Soo Kim
- Department of Neurology, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Hyo-Jung Kim
- Research Administration Team, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Seo-Young Choi
- Department of Neurology, Pusan National University Hospital, Pusan National University School of Medicine and Biomedical Research Institute, Busan, Republic of Korea
| | - Kwang-Dong Choi
- Department of Neurology, Pusan National University Hospital, Pusan National University School of Medicine and Biomedical Research Institute, Busan, Republic of Korea
| | - David S Zee
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, USA
| | - Jae-Hwan Choi
- Department of Neurology, Pusan National University School of Medicine, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea.
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48
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Abstract
A fundamental challenge to the brain is how to prevent intrusive movements when quiet is needed. Unwanted limb movements such as tremor impair fine motor control and unwanted eye drifts such as nystagmus impair vision. A stable platform is also necessary to launch accurate movements. Accordingly, nature has designed control systems with agonist (excitation) and antagonist (inhibition) muscle pairs functioning in push-pull, around a steady level of balanced tonic activity, the set-point Sensory information can be organized similarly, as in the vestibulo-ocular reflex, which generates eye movements that compensate for head movements. The semicircular canals, working in coplanar pairs, one in each labyrinth, are reciprocally excited and inhibited as they transduce head rotations. The relative change in activity is relayed to the vestibular nuclei, which operate around a set-point of stable balanced activity. When a pathological imbalance occurs, producing unwanted nystagmus without head movement, an adaptive mechanism restores the proper set-point and eliminates the nystagmus. Here we used 90 min of continuous 7 T magnetic field labyrinthine stimulation (MVS) in normal humans to produce sustained nystagmus simulating vestibular imbalance. We identified multiple time-scale processes towards a new zero set-point showing that MVS is an excellent paradigm to investigate the neurobiology of set-point adaptation.This article is part of the themed issue 'Movement suppression: brain mechanisms for stopping and stillness'.
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Affiliation(s)
- D S Zee
- Department of Neurology, Johns Hopkins Hospital, 600 N. Wolfe St, Baltimore, MD 21287, USA
| | - P Jareonsettasin
- Oxford University Hospitals, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - R J Leigh
- Department of Neurology, Case Western Reserve University, 11100 Euclid Avenue, Cleveland, OH 44106-5040, USA
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49
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Otero-Millan J, Treviño C, Winnick A, Zee DS, Carey JP, Kheradmand A. The video ocular counter-roll (vOCR): a clinical test to detect loss of otolith-ocular function. Acta Otolaryngol 2017; 137:593-597. [PMID: 28084887 DOI: 10.1080/00016489.2016.1269364] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
CONCLUSION vOCR can detect loss of otolith-ocular function without specifying the side of vestibular loss. Since vOCR is measured with a simple head tilt maneuver, it can be potentially used as a bedside clinical test in combination with video head impulse test. OBJECTIVE Video-oculography (VOG) goggles are being integrated into the bedside assessment of patients with vestibular disorders. Lacking, however, is a method to evaluate otolith function. This study validated a VOG test for loss of otolith function. METHODS VOG was used to measure ocular counter-roll (vOCR) in 12 healthy controls, 14 patients with unilateral vestibular loss (UVL), and six patients with bilateral vestibular loss (BVL) with a static lateral head tilt of 30°. The results were compared with vestibular evoked myogenic potentials (VEMP), a widely-used laboratory test of otolith function. RESULTS The average vOCR for healthy controls (4.6°) was significantly different from UVL (2.7°) and BVL (1.6°) patients (p < 0.0001). The vOCR and VEMP measurements were correlated across subjects, especially the click and tap oVEMPs (click oVEMP R = 0.45, tap oVEMP R = 0.51; p < 0.0003). The receiver operator characteristic (ROC) analysis showed that vOCR and VEMPs detected loss of otolith function equally well. The best threshold for vOCR to detect vestibular loss was at 3°. The vOCR values from the side of vestibular loss and the healthy side were not different in UVL patients (2.53° vs 2.8°; p = 0.59).
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Affiliation(s)
| | - Carolina Treviño
- Department of Otolaryngology, University of Minnesota Medical Center, Minneapolis, MN, USA
| | - Ariel Winnick
- Department of Neurology, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - David S. Zee
- Department of Neurology, The Johns Hopkins Hospital, Baltimore, MD, USA
- Department of Otolaryngology, The Johns Hopkins Hospital, Baltimore, MD, USA
- Department of Neuroscience, The Johns Hopkins Hospital, Baltimore, MD, USA
- Department of Ophthalmology, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - John P. Carey
- Department of Otolaryngology, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - Amir Kheradmand
- Department of Neurology, The Johns Hopkins Hospital, Baltimore, MD, USA
- Department of Otolaryngology, The Johns Hopkins Hospital, Baltimore, MD, USA
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50
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Colagiorgio P, Versino M, Colnaghi S, Quaglieri S, Manfrin M, Zamaro E, Mantokoudis G, Zee DS, Ramat S. New insights into vestibular-saccade interaction based on covert corrective saccades in patients with unilateral vestibular deficits. J Neurophysiol 2017; 117:2324-2338. [PMID: 28404827 DOI: 10.1152/jn.00864.2016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 04/10/2017] [Accepted: 04/10/2017] [Indexed: 11/22/2022] Open
Abstract
In response to passive high-acceleration head impulses, patients with low vestibulo-ocular reflex (VOR) gains often produce covert (executed while the head is still moving) corrective saccades in the direction of deficient slow phases. Here we examined 23 patients using passive, and 9 also active, head impulses with acute (< 10 days from onset) unilateral vestibular neuritis and low VOR gains. We found that when corrective saccades are larger than 10°, the slow-phase component of the VOR is inhibited, even though inhibition increases further the time to reacquire the fixation target. We also found that 1) saccades are faster and more accurate if the residual VOR gain is higher, 2) saccades also compensate for the head displacement that occurs during the saccade, and 3) the amplitude-peak velocity relationship of the larger corrective saccades deviates from that of head-fixed saccades of the same size. We propose a mathematical model to account for these findings hypothesizing that covert saccades are driven by a desired gaze position signal based on a prediction of head displacement using vestibular and extravestibular signals, covert saccades are controlled by a gaze feedback loop, and the VOR command is modulated according to predicted saccade amplitude. A central and novel feature of the model is that the brain develops two separate estimates of head rotation, one for generating saccades while the head is moving and the other for generating slow phases. Furthermore, while the model was developed for gaze-stabilizing behavior during passively induced head impulses, it also simulates both active gaze-stabilizing and active gaze-shifting eye movements.NEW & NOTEWORTHY During active or passive head impulses while fixating stationary targets, low vestibulo-ocular gain subjects produce corrective saccades when the head is still moving. The mechanisms driving these covert saccades are poorly understood. We propose a mathematical model showing that the brain develops two separate estimates of head rotation: a lower level one, presumably in the vestibular nuclei, used to generate the slow-phase component of the response, and a higher level one, within a gaze feedback loop, used to drive corrective saccades.
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Affiliation(s)
- Paolo Colagiorgio
- Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy
| | - Maurizio Versino
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy.,Laboratory of Neuro-otology and Neuro-ophthalmology, C. Mondino National Neurological Institute, Pavia, Italy
| | - Silvia Colnaghi
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy.,Inter-Department Multiple Sclerosis Research Centre, C. Mondino National Neurological Institute, Pavia, Italy
| | - Silvia Quaglieri
- UOC Otorinolaringoiatria, Fondazione IRCCS San Matteo and University of Pavia, Pavia, Italy
| | - Marco Manfrin
- UOC Otorinolaringoiatria, Fondazione IRCCS San Matteo and University of Pavia, Pavia, Italy
| | - Ewa Zamaro
- Department of Otorhinolaryngology, Head and Neck Surgery, lnselspital, Bern University Hospital, University of Bern, Bern, Switzerland; and
| | - Georgios Mantokoudis
- Department of Otorhinolaryngology, Head and Neck Surgery, lnselspital, Bern University Hospital, University of Bern, Bern, Switzerland; and
| | - David S Zee
- Department of Neurology, Otolaryngology-Head and Neck Surgery, Neuroscience, Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Stefano Ramat
- Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy;
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