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Abstract
Technological advances provide a number of options for glaucoma monitoring outside the office setting, including home-based tonometry and perimetry. This has the potential to revolutionize management of this chronic disease, improve access to care, and enhance patient engagement. Here, we provide an overview of existing technologies for home-based glaucoma monitoring. We also discuss areas for future research and the potential applications of these technologies to telemedicine, which has been brought to the forefront during the ongoing COVID-19 pandemic.
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Affiliation(s)
- Inas F Aboobakar
- Department of Ophthalmology , Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - David S Friedman
- Department of Ophthalmology , Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
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Liu X, Kale AU, Capewell N, Talbot N, Ahmed S, Keane PA, Mollan S, Belli A, Blanch RJ, Veenith T, Denniston AK. Optical coherence tomography (OCT) in unconscious and systemically unwell patients using a mobile OCT device: a pilot study. BMJ Open 2019; 9:e030882. [PMID: 31699727 PMCID: PMC6858135 DOI: 10.1136/bmjopen-2019-030882] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE This study aims to evaluate the feasibility of retinal imaging in critical care using a novel mobile optical coherence tomography (OCT) device. The Heidelberg SPECTRALIS FLEX module (Heidelberg Engineering, Heidelberg, Germany) is an OCT unit with a boom arm, enabling ocular OCT assessment in less mobile patients. DESIGN We undertook an evaluation of the feasibility of using the SPECTRALIS FLEX for undertaking ocular OCT images in unconscious and critically ill patients. SETTING This study was conducted in the critical care unit of a large tertiary referral unit in the United Kingdom. PARTICIPANTS 13 systemically unwell patients admitted to the critical care unit were purposively sampled to enable evaluation in patients with a range of clinical states. OUTCOME MEASURES The primary outcome was the feasibility of acquiring clinically interpretable OCT scans on a consecutive series of patients. The standardised scanning protocol included macula-focused OCT, OCT optic nerve head (ONH), OCT angiography (OCTA) of the macula and ONH OCTA. RESULTS OCT images from 13 patients were attempted. The success rates of each scan type are 84% for OCT macula, 76% for OCT ONH, 56% for OCTA macula and 36% for OCTA ONH. The overall mean success rate of scans per patient was 64% (95% CI 46% to 81%). Clinicians reported clinical value in 100% scans which were successfully obtained, including both ruling in and ruling out relevant ocular complications such as corneal thinning, macular oedema and optic disc swelling. The most common causes of failure to achieve clinically interpretable scans were inadequately sustained OCT alignment in delirious patients and a compromised ocular surface due to corneal exposure. CONCLUSIONS This prospective evaluation indicates the feasibility and potential clinical value of the SPECTRALIS FLEX OCT system on the critical care unit. Portable OCT systems have the potential to bring instrument-based ophthalmic assessment to critically ill patients, enabling detection and micron-level monitoring of ocular complications.
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Affiliation(s)
- Xiaoxuan Liu
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- Academic Unit of Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
- Health Data Research UK, London, United Kingdom
| | - Aditya Uday Kale
- Academic Unit of Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Nicholas Capewell
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Nicholas Talbot
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Sumiya Ahmed
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Pearse A Keane
- Health Data Research UK, London, United Kingdom
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Susan Mollan
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- Centre for Rare Diseases, Institute of Translational Medicine, Birmingham, UK
| | - Antonio Belli
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- Institute of Inflammation and Ageing, University of Birmingham, College of Medical and Dental Sciences, Birmingham, UK
- Department of Critical Care Medicine, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Richard J Blanch
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- Academic Department of Military Surgery and Trauma, Royal Centre for Defence Medicine, Birmingham, UK
| | - Tonny Veenith
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- Department of Critical Care Medicine, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Alastair K Denniston
- Ophthalmology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- Academic Unit of Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
- Health Data Research UK, London, United Kingdom
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Centre for Rare Diseases, Institute of Translational Medicine, Birmingham, UK
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Song G, Chu KK, Kim S, Crose M, Cox B, Jelly ET, Ulrich JN, Wax A. First Clinical Application of Low-Cost OCT. Transl Vis Sci Technol 2019; 8:61. [PMID: 31293815 PMCID: PMC6602122 DOI: 10.1167/tvst.8.3.61] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 05/07/2019] [Indexed: 12/17/2022] Open
Abstract
Purpose We present the design of a new low-cost optical coherence tomography (OCT) system and compare its retinal imaging capabilities to a standard commercial system through a clinical study. Methods A spectral-domain OCT system was designed using various cost-reduction techniques to be low-cost, highly portable, and completely stand-alone. Clinical imaging was performed on 120 eyes of 60 patients (60 eyes of normal volunteers and 60 eyes with retinal disease) using both the low-cost OCT and a Heidelberg Engineering Spectralis OCT. Contrast-to-noise ratio (CNR) was measured from resulting images to determine system performance. Results The low-cost OCT system was successfully applied to clinical imaging of the retina. The system offers an axial resolution of 8.0 μm, a lateral resolution of 19.6 μm, and an imaging depth of 2.7 mm for a 6.6-mm field of view in the X and Y directions. Total cost is $5037, a significant size reduction compared to current commercial higher performance systems. Mean CNR value of low-cost OCT images is only 5.6% lower compared to the Heidelberg Spectralis. Conclusions The images captured with the low-cost OCT were of adequate resolution and allowed for clinical diagnostics. It offers comparable performance as a retinal screening tool at a fraction of the cost of current commercial systems. Translational Relevance Low-cost OCT has the potential to increase access to retinal imaging.
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Affiliation(s)
- Ge Song
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Kengyeh K Chu
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Sanghoon Kim
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Michael Crose
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Brian Cox
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Evan T Jelly
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - J Niklas Ulrich
- Kittner Eye Center, University of North Carolina, Chapel Hill, NC, USA
| | - Adam Wax
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
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Grundy SJ, Tshering L, Wanjala SW, Diamond MB, Audi MS, Prasad S, Shinohara RT, Rogo D, Wangmo D, Wangdi U, Aarayang A, Tshering T, Burke TF, Mateen FJ. Retinal Parameters as Compared with Head Circumference, Height, Weight, and Body Mass Index in Children in Kenya and Bhutan. Am J Trop Med Hyg 2018; 99:482-488. [PMID: 29893200 PMCID: PMC6090321 DOI: 10.4269/ajtmh.17-0943] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The retina shares embryological derivation with the brain and may provide a new measurement of overall growth status, especially useful in resource-limited settings. Optical coherence tomography (OCT) provides detailed quantification of retinal structures. We enrolled community-dwelling children ages 3–11 years old in Siaya, Kenya and Thimphu, Bhutan in 2016. We measured head circumference (age < 5 years only), height, and weight, and standardized these by age and gender. Research staff performed OCT (iScan; Optovue, Inc., Fremont, CA), measuring the peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC) thicknesses. A neuro-ophthalmologist performed quality control for centration, motion artifact, and algorithm-derived quality scores. Generalized estimating equations were used to determine the relationship between anthropometric and retinal measurements. Two hundred and fifty-eight children (139 females, average age 6.4 years) successfully completed at least one retinal scan, totaling 1,048 scans. Nine hundred and twenty-two scans (88.0%) were deemed usable. Fifty-three of the 258 children (20.5%) were able to complete all six scans. Kenyan children had a thinner average GCC (P < 0.001) than Bhutanese children after adjustment for age and gender, but not RNFL (P = 0.70). In models adjusting for age, gender, and study location, none of standardized height, weight, and body mass index (BMI) were statistically significantly associated with RNFL or GCC. We determined that OCT is feasible in some children in resource-limited settings, particularly those > 4 years old, using the iScan device. We found no evidence for GCC or RNFL as a proxy for height-, weight-, or BMI-for-age. The variation in mean GCC thickness in Asian versus African children warrants further investigation.
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Affiliation(s)
- Sara J Grundy
- Neurological Clinical Research Institute, Massachusetts General Hospital, Boston, Massachusetts
| | - Lhab Tshering
- Department of Psychiatry, Jigme Dorji Wangchuck National Referral Hospital, Thimphu, Bhutan
| | | | - Megan B Diamond
- Neurological Clinical Research Institute, Massachusetts General Hospital, Boston, Massachusetts
| | | | - Sashank Prasad
- Division of Neuro-Ophthalmology, Brigham and Women's Hospital, Boston, Massachusetts.,Harvard Medical School, Boston, Massachusetts.,Neurological Clinical Research Institute, Massachusetts General Hospital, Boston, Massachusetts
| | - Russell T Shinohara
- Department of Biostatistics, University of Pennsylvania, Philadelphia, Pennsylvania
| | | | - Dechen Wangmo
- Department of Ophthalmology, Jigme Dorji Wangchuck National Referral Hospital, Thimphu, Bhutan
| | - Ugyen Wangdi
- Department of Ophthalmology, Jigme Dorji Wangchuck National Referral Hospital, Thimphu, Bhutan
| | - Abi Aarayang
- Department of Ophthalmology, Jigme Dorji Wangchuck National Referral Hospital, Thimphu, Bhutan
| | - Thukten Tshering
- Department of Ophthalmology, Jigme Dorji Wangchuck National Referral Hospital, Thimphu, Bhutan
| | - Thomas F Burke
- Harvard T.H. Chan School of Public Health, Boston, Massachusetts.,Division of Global Health and Human Rights, Massachusetts General Hospital, Boston, Massachusetts
| | - Farrah J Mateen
- Harvard Medical School, Boston, Massachusetts.,Neurological Clinical Research Institute, Massachusetts General Hospital, Boston, Massachusetts
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Mukherjee N, McBurney-Lin S, Kuo A, Bedlack R, Tseng H. Retinal thinning in amyotrophic lateral sclerosis patients without ophthalmic disease. PLoS One 2017; 12:e0185242. [PMID: 28945811 PMCID: PMC5612691 DOI: 10.1371/journal.pone.0185242] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 09/09/2017] [Indexed: 02/06/2023] Open
Abstract
IMPORTANCE Amyotrophic lateral sclerosis (ALS) is a fatal, rapidly progressive neurodegenerative disease that primarily affects motor neurons. Recently, three causative genes have been implicated in both ALS and glaucoma. However, it is still uncertain whether patients with ALS have neurodegeneration in their retinas. If so, retinal thickness measurements might be a useful biomarker for ALS progression. Previous work in this area has been inconclusive, as it has not taken into account the effect of ophthalmic diseases on retinal thinning. OBJECTIVE To determine whether there are differences in retinal neurons in ALS patients utilizing spectral-domain optical coherence tomography (SD-OCT). We tested the hypothesis that ALS patients exhibit retinal neurodegeneration that is not associated with ophthalmic diseases. DESIGN, SETTINGS AND PARTICIPANTS Observational, comparative, cross-sectional study performed on patients recruited from the Duke University Medical Center ALS clinic. Patients underwent a comprehensive ophthalmologic examination to rule out ocular pathology. 21 patients met inclusion criteria. Two eyes with ocular pathology were excluded, leading to a total of 40 eyes of 21 patients included in the study. Retinal neurodegeneration was assessed by retinal nerve fiber layer (RNFL) thickness measurement using SD-OCT (Spectralis; Heidelberg Engineering). MAIN OUTCOMES AND MEASURES ALS disease severity, determined through the ALS Functional Rating Scale (ALSFRS-R); mean and six sector RNFL thickness values compared to age-adjusted values in the normative database provided by Heidelberg Engineering; RNFL thickness correlation with ALSFRS-R, ALSFRS-R progression rate, forced vital capacity (FVC), and visual acuity. RESULTS ALSFRS-R mean score was 30+/-10. Mean RNFL thickness in ALS patients was 88.95 +/- 10.8 microns, significantly thinner than values in the normative database (95.81 +/- 0.8). These RNFL thickness values did not demonstrate correlation to ALSFRS-R score, ALSFRS-R progression rate, FVC, intraocular pressure, or visual acuity. CONCLUSIONS Using SD-OCT, our study shows that ALS patients without ocular pathology exhibit thinned retinal layers. Future studies are warranted to clarify the clinical relationship between retinal thinning and motor neuron loss in ALS.
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Affiliation(s)
- Nisha Mukherjee
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Shan McBurney-Lin
- Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Anthony Kuo
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Richard Bedlack
- Duke ALS Clinic, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Henry Tseng
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail:
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Yang J, Liu L, Campbell JP, Huang D, Liu G. Handheld optical coherence tomography angiography. BIOMEDICAL OPTICS EXPRESS 2017; 8:2287-2300. [PMID: 28736672 PMCID: PMC5516829 DOI: 10.1364/boe.8.002287] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 02/25/2017] [Accepted: 03/12/2017] [Indexed: 05/03/2023]
Abstract
We developed a handheld optical coherence tomography angiography (OCTA) system using a 100-kHz swept-source laser. The handheld probe weighs 0.4 kg and measures 20.6 × 12.8 × 4.6 cm3. The system has dedicated features for handheld operation. The probe is equipped with a mini iris camera for easy alignment. Real-time display of the en face OCT and cross-sectional OCT images in the system allows accurately locating the imaging target. Fast automatic focusing was achieved by an electrically tunable lens controlled by a golden-section search algorithm. An extended axial imaging range of 6 mm allows easy alignment. A registration algorithm using cross-correlation to register adjacent OCT B-frames with propagation from the central frame was used to effectively minimize motion artifacts in volumetric OCTA images captured in relatively short durations of 1 and 2.1 seconds. 2.5 × 2.5 mm (200 × 200 pixels) and 3.5 × 3.5 mm (300 × 300 pixels) retinal angiograms were demonstrated on two awake adult human subjects without the use of any mydriatic eye drops.
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