Temporal Changes in Cerebral Blood Flow during Migraine with Aura of Alternating Left and Right Homonymous Hemianopsia

A 16-year-old boy presented with sudden left homonymous hemianopsia followed by right ocular and occipital pain. Arterial spin labeling (ASL), a non-contrast magnetic resonance imaging technique used to evaluate perfusion, showed a decrease in cerebral blood flow in the right occipital lobe. Three hours after admission, the patient experienced right homonymous hemianopsia and ocular-to-occipital pain on the contralateral side. ASL revealed a decreased cerebral blood flow in the left occipital lobe. We ultimately diagnosed the patient with first-time migraine with aura, in which cortical spreading depression was visualized as decreased cerebral blood flow using ASL.

Homonymous hemianopia due to cerebral venous thrombosis: A case report

RATIONALE

Diagnosing cerebral venous thrombosis (CVT) can be difficult because of nonspecific symptoms, such as headache and homonymous hemianopia (HH). Herein, we present a case of delayed CVT diagnosis due to nonspecific neurological symptoms and nonprominent lesions in a patient with HH.

PATIENT CONCERN

A 65-year-old woman presented with a sudden onset headache accompanied by right HH that lasted for 1 day. Brain computed tomography and magnetic resonance imaging were initially performed due to suspicion of ischemic lesions or hemorrhage in the left postchiasmal visual pathway; however, no remarkable acute brain lesions were detected. Ophthalmological examinations revealed no notable findings, except for a definite field defect in the Humphrey visual field test. The headaches then waxed and waned but recurred 3 days after the initial symptom.A repeat brain magnetic resonance imaging was performed, which revealed left sectoral gyral swelling and vascular enhancement in the occipital lobe. To further evaluate venous drainage, additional 3-dimensional cerebral computed tomography angiography and 4-vessel angiography were conducted, revealing a partial filling defect in the left transverse sinus and superior venous drainage impairment. These findings suggested the presence of venous thrombosis in the left transverse sinus.

DIAGNOSIS

The patient was diagnosed with thrombosis of the left transverse sinus, which subsequently caused the right HH.

INTERVENTION

Anticoagulation therapy with parenteral heparin was started as soon as the diagnosis of CVT was confirmed. Eventually, the patient was solely managed with oral warfarin administration.

OUTCOMES

Following 3 days of treatment, her headache resolved, and a subsequent visual field testing conducted 2 weeks later revealed a definite improvement in the field defect.

LESSONS

Despite its favorable prognosis, CVT can be challenging to diagnose. CVT should be considered as a differential diagnosis when diagnosing patients who present with headaches accompanied by HH without prominent brain lesions.

UK exceptional case driving application outcomes in post-stroke homonymous hemianopia: results from a clinical study

PURPOSE

We report results in relation to returning to driving in the UK under the exceptional cases rule for visual field loss.

METHODS

The Hemianopia Adaptation Study is a prospective clinical study recruiting adult stroke survivors with new onset homonymous hemianopia. The mobility assessment course (MAC) was used to measure navigational scanning. Car drivers were offered a 1-year post-stroke assessment to consider referral for driving assessment.

RESULTS

Of 144 participants, 51 were eligible for driving assessment, with 13 (25.4%) accepting appointment for UK Driving and Vehicle Licensing Agency (DVLA) referral. A statistically significant difference in gender and baseline Barthel (stroke severity) scores was found between those requesting referral and those declining (p = 0.046; p < 0.001). MAC outcomes were significantly different, with those referred having a lower percentage of target omissions (9.0%) and faster mean course completion time (46.0 s), than those not referred (28.3%/72.5 s) (p = 0.006/p < 0.001). Twelve of the 13 referred were offered a driving assessment by the DVLA. All 12 passed and returned to driving.

CONCLUSIONS

It is possible for individuals with post-stroke homonymous hemianopia to return to driving, where exceptional cases criteria are met. There is evidence to support use of the MAC as a clinical measurement of adaptation.IMPLICATIONS FOR REHABILITATIONIndividuals with post-stroke homonymous hemianopia should be fully informed regarding driving regulations that can differ between countries and sometimes different states within a country, as well as provided with the support and opportunity to consider a return to driving if appropriate.Professionals providing care within the stroke multi-disciplinary team should be aware that it is possible for patients with homonymous hemianopia to return to driving, when exceptional cases criteria are met.The mobility assessment course (MAC) should be considered as a clinical measurement of adaptation in homonymous hemianopia.A cut-off score of ≤25% omissions on MAC could be employed to determine those likely to adapt to hemianopia long-term and potentially return to driving.

Visual change as the presenting symptom of a suspected metastatic brain lesion in esophageal cancer: A case report

INTRODUCTION

Esophageal cancer is the seventh most common malignancy worldwide and the sixth leading cause of cancer mortality with an overall survival rate of <20%. Esophageal cancer frequently metastasizes to distant lymph nodes, lungs, liver, and bones. Cerebral metastases originating from esophageal cancer are rare and often carry a poor prognosis as do most all metastatic lesions in esophageal cancer.

CASE PRESENTATION

In this report, we describe a 55-year-old patient with past history of esophageal carcinoma who presented with blurred vision after taking ethambutol for tuberculosis. Ethambutol-induced optic neuropathy was the lead diagnosis. Initial vision testing was normal so additional testing with visual field examination was warranted. The visual field examination revealed homonymous hemianopsia. Subsequent magnetic resonance imaging of his brain, demonstrated a focal lesion, consistent with but not diagnostic of a brain metastasis likely from his primary esophageal malignancy.

CONCLUSION

We conclude that a careful review of the medical history and comprehensive assessment are essential in establishing an obscure clinical diagnosis especially in the event that an uncommon metastatic lesion is encountered.

Structure-function relationship between magnetic resonance imaging lesion areas and visual field defects in initial optic neuritis with altitudinal hemianopsia

PURPOSE

To study the spatial association of magnetic resonance imaging (MRI) contrast enhancement (CE) areas with visual field defect (VFD) asymmetry in initial cases of optic neuritis (ON) with altitudinal hemianopsia (AH) with reference to nonarteritic anterior ischemic optic neuropathy (NAION) with AH.

STUDY DESIGN

Multicenter, cross-sectional study.

METHODS

The present study comprised 19 ON patients and 20 NAION patients with AH who underwent orbital contrast fat-suppressed MRI. The signal-to-intensity ratio (SIR) was calculated by dividing the maximum CE of the optic nerve by the mean CE of the cerebral white matter in 11 coronal sections at 3-mm intervals from immediately posterior to the eyeball to the optic chiasm. Sections in ON patients with an SIR exceeding the mean plus 2 standard deviations of the SIR at the corresponding section in the NAION group were considered abnormal. The correlation between upper-to-lower CE asymmetry in the maximum SIR section and VFD counterpart was determined.

RESULTS

The ON group had significantly higher maximum SIR than that of the NAION group (1.77 ± 0.88 vs. 1.25 ± 0.32; P < .01). Seven of the 19 patients had sections with abnormally high CE extending posteriorly beyond the orbital apex. Significant spatial correspondence was observed between CE and VFD asymmetry (rs = 0.563; P = .015) in the ON group but not in the NAION group (rs = - 0. 048; P = .850).

CONCLUSIONS

ON patients with AH frequently show CE even in the intracerebral optic nerve, maintaining a moderate structure-function correspondence.

Demographics, Risk Factors, and Etiology of Posterior Cerebral Artery Stroke Causing Homonymous Hemianopia

BACKGROUND

Posterior cerebral artery (PCA) strokes account for up to 10% of all ischemic strokes, often presenting with homonymous hemianopia. The proportion of these strokes attributed to various etiologies varies widely in previously published studies, owing largely to differing patient populations, definitions of stroke pathogenesis, and vascular territories involved. The Causative Classification System (CCS), an automated version of the Stop Stroke Study (SSS) Trial of Org 10,172 in Acute Stroke Treatment (TOAST) system, allows for a more rigorous assignment of stroke etiology.

METHODS

We excerpted clinical and imaging data on 85 patients who had PCA stroke with homonymous hemianopia examined at the University of Michigan. We compared the stroke risk factor profile of our PCA cohort with that of 135 patients with stroke in the distribution of the internal carotid artery (ICA) and middle cerebral artery (MCA) in an unpublished University of Michigan registry. We applied the CCS web-based calculator to our PCA cohort to determine stroke etiology.

RESULTS

In our PCA cohort, 80.0% had at least 2 conventional stroke risk factors and 30.6% had 4 risk factors, most commonly systemic hypertension. The risk factor profile of our PCA cohort resembled that of our ICA/MCA cohort except that the mean age of our PCA cohort was more than a decade younger and had a significantly lower frequency of atrial fibrillation (AF) than our ICA/MCA cohort. In nearly half of the patients with AF in our PCA cohort, AF was diagnosed after the stroke. Among stroke etiologies in our PCA cohort, 40.0% were of undetermined cause, 30.6% were from cardioaortic embolism, 17.6% were from other determined causes, and only 11.8% were from supra-aortic large artery atherosclerosis. Strokes after endovascular or surgical interventions were prominent among other determined causes.

CONCLUSIONS

Most patients in our PCA cohort had multiple conventional stroke risk factors, a finding not previously documented. Mean age at stroke onset and AF frequency were lower than in our ICA/MCA cohort, in agreement with previous studies. As some other studies have found, nearly 1/3 of strokes were attributed to cardioaortic embolism. Within that group, AF was often a poststroke diagnosis, a finding not previously highlighted. Compared with earlier studies, a relatively high portion of strokes were of undetermined etiology and of other determined etiologies, including stroke after endovascular or surgical interventions. Supra-aortic large artery atherosclerosis was a relatively uncommon explanation for stroke.

Presenting Symptoms and Imaging Features of Posterior Cerebral Artery Stroke Causing Homonymous Hemianopia

BACKGROUND

Posterior cerebral artery (PCA) stroke is a common cause of homonymous hemianopia and other neurologic deficits associated with more proximal ischemia in the vertebrobasilar circuit. Localization of the process can be challenging unless the symptom complex is well recognized, yet early diagnosis is critical to forestall dangerous driving and repeated stroke. We undertook this study to provide additional detail about the presenting symptoms and signs and their correlation with imaging abnormalities and stroke etiology.

METHODS

Retrospective study of medical records of patients presenting to a single tertiary care academic center between 2009 and 2020 with homonymous hemianopia from PCA stroke. We excerpted data on symptoms, visual and neurologic signs, incident medical procedures and diagnoses, and imaging features. We determined stroke etiology using the Causative Classification Stroke system.

RESULTS

In a cohort of 85 patients, 90% of strokes occurred without preceding symptoms. But in retrospect, 10% of strokes did have warning symptoms. In 20% of patients, strokes followed within 72 hours of a medical or surgical procedure or newly identified medical condition. In the subgroups of patients whose records contained a description of visual symptoms, 87% reported the visual sensation as negative, and 66% realized that it was located in a hemifield in both eyes. Concurrent nonvisual symptoms were present in 43% of patients, consisting commonly of numbness, tingling, and new headache. Infarction located outside the visual cortex affected primarily the temporal lobe, thalamus, and cerebellum, reflecting the widespread nature of ischemia. Nonvisual clinical manifestations and arterial cutoffs on imaging were associated with thalamic infarction, but the clinical features and location of the infarction did not correlate with the etiology of the stroke.

CONCLUSIONS

In this cohort, clinical localization of the stroke was aided by the fact that many patients could lateralize their visual symptoms and had nonvisual symptoms suggestive of ischemia affecting the proximal vertebrobasilar circuit. Numbness and tingling were strongly linked to concurrent thalamic infarction. Clinical features and infarct location were not associated with the etiology of the stroke.

Occipital Nocardia Abscess Presenting With Positive Visual Phenomenon and Quadrantanopsia

ABSTRACT

A 74-year-old man with chronic obstructive pulmonary disease, glaucoma, and Stage IIIB squamous cell lung cancer experienced several minutes of flashing lights in his right visual hemifield, followed by onset of a right visual field defect. On examination, the patient had a right homonymous hemianopsia that was most dense inferiorly by confrontation testing. Emergent CT scan of the head revealed a 2.5 × 3 cm hypodensity in the left occipital lobe, which was interpreted as an acute stroke. Continuous EEG monitoring captured left posterior quadrant seizures that were temporally correlated to the positive visual phenomena. Subsequent MRI of the brain with and without contrast revealed a conglomerate of centrally necrotic and peripherally enhancing mass lesions. On biopsy, a thick purulent material was drained and Gram stain of the sample revealed gram-positive beaded rods, which speciated to Nocardia farcinica . The patient was treated with a six-week course of intravenous meropenem and a one-year course of oral trimethroprim-sulfamethoxazole. On follow-up, the patient experienced resolution of the right visual field deficit.

Objective Assessment of Visual Field Defects Caused by Optic Chiasm and Its Posterior Visual Pathway Injury

OBJECTIVES

To investigate the characteristics and objective assessment method of visual field defects caused by optic chiasm and its posterior visual pathway injury.

METHODS

Typical cases of visual field defects caused by injuries to the optic chiasm, optic tracts, optic radiations, and visual cortex were selected. Visual field examinations, visual evoked potential (VEP) and multifocal visual evolved potential (mfVEP) measurements, craniocerebral CT/MRI, and retinal optical coherence tomography (OCT) were performed, respectively, and the aforementioned visual electrophysiological and neuroimaging indicators were analyzed comprehensively.

RESULTS

The electrophysiological manifestations of visual field defects caused by optic chiasm injuries were bitemporal hemianopsia mfVEP abnormalities. The visual field defects caused by optic tract, optic radiation, and visual cortex injuries were all manifested homonymous hemianopsia mfVEP abnormalities contralateral to the lesion. Mild relative afferent pupil disorder (RAPD) and characteristic optic nerve atrophy were observed in hemianopsia patients with optic tract injuries, but not in patients with optic radiation or visual cortex injuries. Neuroimaging could provide morphological evidence of damages to the optic chiasm and its posterior visual pathway.

CONCLUSIONS

Visual field defects caused by optic chiasm, optic tract, optic radiation, and visual cortex injuries have their respective characteristics. The combined application of mfVEP and static visual field measurements, in combination with neuroimaging, can maximize the assessment of the location and degree of visual pathway damage, providing an effective scheme for the identification of such injuries.

Clinical Reasoning: A 67-Year-Old Man With Multiple Intracranial Lesions

A wide variety of diseases present with intracranial lesions. In this case report, a 67-year-old man initially presented to an outside hospital with nausea, headache, and ataxia and was found to have multiple intracranial lesions. Diagnostic workup was ultimately unrevealing, and his condition improved after a course of steroids and antibiotics. Unfortunately, symptoms returned 3 months later. MRI of the brain revealed progression of his intracranial lesions. This case highlights a diagnostic approach and general management strategy for patients presenting with undifferentiated intracranial pathology. A final diagnosis is ultimately reached and raises further discussion.

Comparison of a New Head Mount Virtual Reality Perimeter (C3 Field Analyzer) With Automated Field Analyzer in Neuro-Ophthalmic Disorders

BACKGROUND

Automated perimetry in neurologically disabled patients is a challenge. We have devised a patient-friendly virtual reality perimeter, the C3 field analyzer (CFA). We aim to assess the utility of this as a visual field-testing device in neuro-ophthalmic patients for screening and monitoring.

METHODS

Neuro-ophthalmic patients and controls were selected to participate in the study between September and December 2018. They randomly underwent either the CFA or automated field analyzer (HFA) first followed by the other in an undilated state. The CFA results were compared with the HFA, and the correlation of the pattern of the field defect was assessed by an independent masked physician.

RESULTS

In total, 59 eyes of 33 neuro-ophthalmic patients (cases) and another 95 normal individuals (controls) were enrolled. CFA was found to have greater proportion of reliable fields (81.4%) than HFA (59.3%) ( P = 0.009). There were less false negatives ( P < 0.001) and more false positives in CFA ( P < 0.001) among neuro-ophthalmic patients compared with controls. Among neuro-ophthalmology patients, the number of fixation losses was greater with CFA ( P < 0.001), whereas false negatives were greater in HFA ( P < 0.001). On assessing the pattern of the field defects, we found that there was almost 70% correlation of CFA with HFA. Moreover, in classical neurological fields such as hemianopia, the correlation was 87.5%.

CONCLUSIONS

The CFA seems to correlate well with HFA in classic neurological fields such as hemianopias and may serve as an alternative in patients unable to perform a standard automated perimetry. Further developments are currently underway to incorporate threshold testing.

Surgical approach for traumatic chiasmal syndrome and complete third nerve palsy following severe head trauma

Traumatic chiasmal syndrome and traumatic third nerve palsies are rare entities usually caused by severe, high-speed, closed-head road accidents that require a thorough diagnostic work-up and complex medical and surgical management. This report presents the case of a young adult who was involved in a motorcycle accident and sustained blunt frontal head trauma, resulting in optical chiasmal syndrome and complete unilateral third nerve palsy. Ophthalmological examination demonstrated a right complete ptosis, a downward and outward position of the right eye with a fixed and dilated pupil, and bitemporal hemianopsia. In addition, funduscopy revealed bilateral optical nerve atrophy. After stabilisation and during follow-up, strabismus surgery was performed with improvement of ocular alignment in the primary position. Subsequently, eyelid surgery was carried out with good amplification of the visual field, particularly on the left side. Although challenging, surgical intervention in these cases should be considered for both functional and cosmetic reasons.

Junctional Scotoma and Patterns of Visual Field Defects Produced by Lesions Involving the Optic Chiasm

BACKGROUND

Lesions of the optic chiasm (OC) typically produce bitemporal hemianopia (BTH) on visual field (VF) testing, whereas lesions located at the nasal optic nerve-chiasmal (ON-OC) junction have been proposed to produce junctional scotoma (JXS), a central defect in the ipsilateral eye with temporal field loss in the contralateral eye. In this study, we investigated whether the pattern of VF loss in patients with chiasmal compression predicted the appearance of the causative lesion on neuroimaging and described the clinical presentation of these patients with different types of VF defect.

METHODS

Retrospective chart review of patients seen in tertiary neuro-ophthalmology practice over 6 consecutive years with lesions abutting or displacing the OC was performed. Lesion size and location relative to the OC on neuroimaging was determined and correlated with VF defects as well as optical coherence tomography (OCT) of the peripapillary retinal nerve fiber layer and macular ganglion cell complex (GCC).

RESULTS

Fifty-three patients were enrolled. VFs demonstrated JXS (n = 18), BTH (n = 14), monocular VF defect (n = 4), and no VF defect (n = 17); 64.7% of cases with normal VFs had radiologic OC compression. Lesion volume was highest in the JXS group, and these patients also had the poorest presenting visual acuity. All patients with JXS showed involvement of the ON-OC junction; however, not all cases showed compression of the OC from the nasal direction (15 of 18), and 17 of 18 also showed compression of one or both prechiasmatic ONs. Compression of the ON-OC junction was also seen in 79% of BTH, 100% of monocular VF defect, and 59% of no VF defect cases. Fifty percent of patients with normal VFs already had thinning of the GCC on OCT. GCC thinning was most pronounced nasally in the BTH group, but diffuse bilateral thinning was found in 38% of cases compared with 60% of JXS. VFs improved in 6 of 6 patients with BTH but only in 5 of 8 JXS cases after treatment.

CONCLUSIONS

JXS is more often seen with larger lesions and when there is compression of both the prechiasmatic ON and ON-OC junction. These patients have worse presenting visual acuity and poorer outcomes. Not all patients with radiologic compression had VF defects, although 50% of patients with normal VFs had evidence of compression on the macular GCC analysis, emphasizing the importance of macular OCT in the evaluation of patients with lesions involving the OC.

Bitemporal Hemianopia Secondary to Acute Zonal Occult Outer Retinopathy

ABSTRACT

A 58-year-old man noticed shadows in the temporal visual field of each eye and photopsias within these scotomas for the past year. Formal visual fields demonstrated bitemporal hemianopia. MRI of the sella was normal, but fundus autofluorescence (FAF) demonstrated an area of hyperautofluorescence in the nasal retina of each eye corresponding to the loss of retinal pigment epithelium and photoreceptors. A diagnosis of acute zonal occult outer retinopathy was made based on the presence of trizonal involvement on FAF. This case is a reminder that bitemporal hemianopia can be caused by a retinopathy involving nasal retina in each eye, and FAF is a very useful test when assessing patients with suspected outer retinal disorders.

Characteristic Visual Field Defect From Lateral Geniculate Body Stroke

ABSTRACT

A 58-year-old man presented with a complaint of subjective visual field loss on the right side and hypertensive emergency. Examination revealed a right homonymous hemianopia. Computed tomography imaging revealed an acute stroke of the left lateral geniculate body. A few months later, automated perimetry revealed characteristic visual field changes associated with this lesion. In this report, the anatomy, pathophysiology, clinical findings, and previously reported etiologies of lateral geniculate body lesions are reviewed.

Irreversible Homonymous Hemianopia Associated with Severe Hyperglycemia and Cerebral Hyperperfusion: A Case Report and Literature Review

A 68-year-old man was admitted to our department because of left incomplete homonymous hemianopia accompanied by hyperglycemia. Both T2-weighted and diffusion-weighted imaging revealed a low signal intensity along the subcortex and high signal intensity along the cortex on the right parietal and occipital lobes. Furthermore, arterial spin labeling and single-photon emission computed tomography showed hyperperfusion at the right parieto-occipital lobe. However, the electroencephalography result was normal. Hyperperfusion improved after controlling the blood glucose levels; nevertheless, homonymous hemianopia remained. We suspect that the irreversible brain damage was attributable to hyperperfusion associated with long-term hyperglycemia.

Homonymous quadrantanopia associated with hyperosmolar hyperglycemic syndrome

We encountered a 64-year-old man with hyperosmolar hyperglycemic syndrome, having a sudden-onset homonymous right inferior quadrantanopia. This is the first documentation of such a phenomenon in hyperosmolar hyperglycemic syndrome. We believe this is a variant of hemianopia in patients with hyperglycemic hyperosmolar syndrome.

Direct and transsynaptic retrograde degeneration and optic nerve head microvascular changes in patients with hemianopia

PURPOSE

To investigate optic nerve head (ONH) microvascular changes secondary to transsynaptic retrograde degeneration (TRD), comperatively with direct retrograde degeneration and healthy controls.

METHODS

Patients with hemianopia due to intracranial lesion included in the study. Intracranial lesion was categorized by location: postgeniculate (causing TRD), chiasmal (causing direct retrograde degeneration). For the postgeniculate lesions, the eye on the same side of the lesion was defined as the ipsilateral eye and the eye on the opposite side as the contralateral eye. Optic disc microvasculature was evaluated with the help of optic coherence tomography angiography.

RESULTS

Sixteen eyes of 16 patients with chiasmal lesion, 28 eyes of 14 patients with postgeniculate lesion, and 30 eyes of 30 healthy subjects were included in the study. Ipsilateral eyes of the patients with postgeniculate lesion had decreased vessel density at the temporal sectors compatible with the affected nasal side of the visual field. Contralateral eyes showed no reduction of the vessel density at the affected nasal sectors. The eyes with chiasmal lesions had decreased vessel density at the peripapillary region and nasal half of the ONH compatible with temporal hemianopia. Vascular changes in the chiasmal lesion were more prominent than those of the postgeniculate lesion. Retinal nerve fiber layer and ganglion cell complex thickness were reduced.

CONCLUSION

Vessel density of ONH was reduced in patients with homonymous hemianopia, providing evidence for TRD secondary to acquired postgeniculate lesion. Direct retrograde degeneration was more prominent in affected sectors when compared to TRD.

Quality of care evaluation in non-functioning pituitary adenoma with chiasm compression: visual outcomes and timing of intervention clinical recommendations based on a systematic literature review and cohort study

PURPOSE

Surgery in patients with non-functioning pituitary macroadenomas (NFMA) is effective in ameliorating visual function. The urgency for decompression, and preferred timing of surgery related to the preoperative severity of dysfunction is unknown.

METHODS

Systematic review for evidence to provide clinical guidance for timing of surgical decompression of the optic chiasm, and a cohort study of 30 NFMA patients, in whom mean deviation (MD), and severity of visual dysfunction was assessed.

RESULTS

Systematic review 44 studies were included with a total of 4789 patients. Postoperatively, visual field defects improved in 87.0% of patients, stabilized in 12.8% and worsened in 1.0%. Specific protocols regarding timing of surgery were not reported. Only seven studies (16.7%) reported on either the duration of visual symptoms, or diagnostic, or treatment delay. Cohort study 30 NFMA patients (50% female, 60 eyes, mean age 58.5 ± 14.8 years), had a median MD of - 5.3 decibel (IQR - 3.1 to - 10.1). MD was strongly correlated with clinical severity (r =  - 0.94, P < 0.0001), and were used for severity of defects cut-off values: (1) normal >  - 2 dB, (2) mild - 2 dB to - 4 dB, (3) moderate - 4 to - 8 dB, (4) severe - 8 to - 17 dB, (5) very severe <  - 17 dB.

CONCLUSION

Surgical decompression is highly effective in improving visual function. Uniform, quantitative grading of visual dysfunction was lacking. MD is a promising quantitative outcome measure. We provide recommendations for the evaluation of timing of surgery, considering severity of visual impairment, which will need further validation based on expert clinical practice.

Acute monocular nasal hemianopia following a mild traumatic brain injury: A case report

INTRODUCTION

Monocular hemianopia is a visual field defect with an uncommon pattern. The etiology of monocular temporal hemianopia has been well-evaluated and has been suggested to result from an optic nerve or chiasmal lesion. However, the etiology of monocular nasal hemianopia remains unclear.

PATIENT CONCERNS

Here, we present the case of a 41-year-old male who was punched on the head with fists during a fight and then suffered from painless blurred vision in the left eye after mild traumatic brain injury. An ophthalmic examination revealed a conjunctival chemosis, periorbital hematoma, and a relative afferent pupillary defect in the left eye. Automated perimetry indicated there was a left side nasal hemianopia along the vertical meridian.

DIAGNOSIS

Examination of the fundus showed there was a normal appearing retina and disc bilaterally. Fluorescein angiography revealed no delayed filling of the vessels. Computed tomography and magnetic resonance imaging showed unremarkable findings of the visual pathways, orbit, and brain. A diagnosis of left traumatic optic neuropathy was made.

INTERVENTIONS

Systemic steroid pulse therapy (1 gram of intravenous methylprednisolone per day) was given to the patient for 3 days.

OUTCOMES

An ophthalmologic examination after treatment indicated there was no obvious improvement in the relative afferent pupillary defect, best corrected visual acuity, and color sense. A second set of automated perimetry results showedno changes after 3 months.

CONCLUSION

Monocular nasal hemianopia caused by traumatic optic neuropathy is uncommon. In this case, monocular nasal hemianopia was likely due to ischemic changes from impairment of the prechiasmal arterial anastomotic network or indirect injury to the lateral prechiasmal nerve fiber.

Pattern-onset and OFFset visual evoked potentials in the diagnosis of hemianopic field defects

BACKGROUND

Visual evoked potentials (VEPs) assess the function of the visual pathway from the retina to the primary visual cortex. There is much evidence that monocular pattern-reversal and flash VEPs can distinguish dysfunction due to chiasmal and post-chiasmal afferent pathway lesions. There is less evidence about the use of pattern-onset/OFFset VEPs to identify post-chiasmic dysfunction.

METHODS

We present nine patients with a range of visual pathway defects that caused dense hemianopic field defects. These patients had pattern onset-OFFset VEPs recorded from an array of occipital electrodes referred to a mid-frontal electrode to checks that appeared for 230 ms and disappeared for 300 ms into a background of mean luminance, in a stimulus field of 30°.

RESULTS

We found pattern-onset VEP components lateralise to occipital electrodes overlaying the functional hemisphere, whereas pattern-OFFset VEP components demonstrate the paradoxical lateralisation phenomenon, described in reversal VEPs, and are maximal over the contralateral occiput.

CONCLUSION

Our findings show how extending the recording time window to include an OFFset VEP facilitates identification of hemianopic visual field defects. We advocate the pattern-onset/OFFset VEP in the assessment of patients with hemianopia, having particular value for patients who are otherwise unable to perform more demanding half-field electrophysiology, imaging or psychophysical testing.

Binasal congruous hemianopia secondary to functional visual loss: A case report

INTRODUCTION

To describe an unusual case of binasal congruous hemianopia secondary to functional visual loss (FVL).

PATIENT CONCERNS

A 24 year-old male was referred originally by his optician at the Emergency Eye Department of the Leicester Royal Infirmary in October 2018 with visual field changes affecting the nasal field of vision in both eyes on routine eye examination. The patient reported ongoing headaches over the last 6 weeks to 8 weeks associated with simultaneous peripheral visual field changes. He also reported rapid loss of weight over the same period of time.

DIAGNOSIS

Binasal congruous hemianopia secondary to FVL.

INTERVENTIONS

Full past medical and ocular history was obtained. The patient underwent full ophthalmic examination including dilated fundoscopy. Visual acuity was recorded with Snellen Chart. Color vision was assessed with Ishihara plates. Peripheral vision was assessed with both Humphrey visual fields and Goldmann visual fields. Optical coherence tomography of the macula and discs was also performed. Neuroimaging investigations included Computerized Tomography (CT) and Magnetic Resonance Imaging (MRI) of the Brain. Electrophysiology investigations included Electroretinogram and visual evoked potentials. Patient was also tested for syphilis.

OUTCOMES

Humphrey visual fields and Goldmann visual fields confirmed the presence of complete binasal field defects. Optical coherence tomography, electroretinogram, visual evoked potentials, CT, MRI were all unremarkable. Ocular examination was normal. Finally, syphilis serology was negative. After 1 year of follow-up, the visual field changes have remained the same.

CONCLUSION

To the best of our knowledge, this is the fourth case described in the literature with complete congruous binasal hemianopia due to FVL. We advocate thorough investigations with multimodal imaging of the fundus, neuroimaging and syphilis serology to exclude serious organic causes for binasal field defects prior to labeling such a field defect functional. Such patients may benefit from neuropsychological input to understand the psychological factors that may be contributing to the symptoms.

Pituitary Adenoma and Papillary Craniopharyngioma: A Rare Case of Collision Tumor and Review of the Literature

BACKGROUND

Pituitary adenomas are the most common lesion of the sellar region. Very few cases in the literature have described their association with craniopharyngiomas in the same anatomic compartment, an entity defined as collision tumors of the sella.

CASE DESCRIPTION

A 35-year-old man presented with headaches and progressive visual disturbances. Radiographic imaging initially highlighted the presence of a pituitary craniopharyngioma. An endoscopic transsphenoidal pituitary approach was performed, during which the tumor was partially resected. The pathology report was positive for 2 entities: a nonfunctioning pituitary adenoma and a papillary craniopharyngioma. This was an unexpected diagnosis based on the surgical and initial radiologic findings.

CONCLUSIONS

To our knowledge, this is the first documented case of a collision tumor of the sella comprising a pituitary adenoma and a craniopharyngioma of the papillary type.

An Alternative Route to the Posterior Half of the Third Ventricle: The Transoccipital Horn Approach. Technical Note

BACKGROUND

Lesions arising or abutting in the posterior half of the third ventricle are approached through established routes to avoid damage of essential brain structures. Occasionally, the features of the lesion require rethinking these traditional routes and tailoring the surgical approach to cause fewer debilitating sequelae to the patient. We introduce a modification of previously described transcortical approaches to lesions of the posterior third ventricle. The technique and possible indications are discussed.

METHODS

Two cases of posterior third ventricle tumors are presented. In both patients, a small posterior fossa and large tentorial veins located along the surgical route, as well as the position of the lesion underneath the internal cerebral veins, encouraged the concept of a novel transoccipital horn approach that was developed to access the tumor with less postoperative deficits.

RESULTS

Both lesions were removed with transitory postoperative visual deficits.

CONCLUSIONS

The transoccipital horn approach is a feasible alternative to other surgical routes to the posterior part of the third ventricle in cases of particularly challenging anatomy and tumor characteristics. It allows reaching the lesion along its major axis, fully exploiting the natural space created by the tumor in its growth and avoiding the internal cerebral veins.

Optic neuropathy causing vertical unilateral hemianopsia after pars plana vitrectomy for a macular hole: A case report

INTRODUCTION

Recent progress in medical technology has resulted in improved surgical outcomes of pars plana vitrectomy (PPV); with microincision systems, the incidence of procedure-related complications during surgery has been reduced. However, unpredictable visual field defects after PPV remain an unresolved issue. A few reports have shown that damage to the retinal neurofibers owing to dry-up during air/fluid exchange or retinal neurotoxicity of the dye used to visualize the internal limiting membrane (ILM), as well as unintentional removal of retinal neurofibers during ILM peeling, are responsible for such visual field disorders. In this report, we present a case of extensive visual field defect due to optic neuropathy exhibiting vertical hemianopsia after PPV.

CASE SUMMARY

A 50-year-old woman underwent PPV and cataract surgery for a macular hole and mild cataract under retrobulbar anesthesia with 3.5 mL of xylocaine. At the time of opening an infusion cannula for PPV, the intraocular lens was herniating, with an acute increase in pressure from the posterior eyeball; thus, intraocular pressure configuration level had to be decreased from the default level, whereas the other procedures including 20% SF6 injection were performed without any modification. The macular hole was closed postoperatively. However, the patient experienced nasal hemianopsia, which turned out to be optic neuropathy, as assessed via electric physiological examinations. The pattern of the visual field defect was not typical for glaucoma or anterior ischemic optic neuropathy. Her optic nerve head was pale at the temporal side soon after the surgery, and her blood pressure was low, suggesting that there may have been a congestion of the optic nerve feeder vessels because of the relatively high pressure in the orbit. The space occupancy with xylocaine and extensively stretched and plumped out eye ball with infusion during PPV may have pressed the surrounding tissue of the optic nerve and the feeder vessels.

CONCLUSION

PPV is safe for most patients; however, individual variations in local and/or systemic conditions may cause complications. Future studies to optimize the surgical condition for each individual patient may be warranted.

Neurorehabilitation of saccadic ocular movement in a patient with a homonymous hemianopia postgeniculate caused by an arteriovenous malformation: A Case Report

RATIONALE

Visual therapy, which includes a restorative and compensatory approach, seems to be a viable treatment option for homonymous defects of the visual field in patients with postgeniculate injury of the visual pathway, due to occipital arteriovenous malformation (AVM). Until now, the Mexican population suffering from homonymous hemianopia did not have health services that provided any type of visual therapy for their condition.

PATIENT CONCERNS

A 31-year-old patient, who underwent a surgical procedure for resection of the AVM, was referred with posterior low vision on the left side.

DIAGNOSES

The patient was diagnosed with left homonymous hemianopia.

INTERVENTIONS

Visual neurorehabilitation therapy (NRT), which integrated restorative and compensatory approaches, was administered for 3 hours each week. NRT included fixation, follow-up, search, peripheral vision, and reading.

OUTCOMES

The NRT did not change visual field defects and, retinotopocally, the same campimetric defects remained. However, after training the tracking ocular movements improved to standard values on the ENG, further, the visual search became more organized. The reading reached a level without mistakes, with rhythm and goog intonation. The Beck test demostrated an improvement in depression symptoms. Regarding the daily life activities, the patient reported significant improvements.

LESSONS

Visual NRT can significantly improve eye movements, as well as the quality of life and independence of the patient. This integral approach could be an effective therapeutic option for homonymous defects of the visual field.

Amygdalohippocampotomy for mesial temporal lobe sclerosis: Epilepsy outcome 5 years after surgery

BACKGROUND

The goal of the present study is the evaluation of the long-term clinical outcome of epilepsy in patients with mesial temporal lobe sclerosis (MTLS) submitted to amygdalohippocampotomy (AHCo). AHCo consists of the lateral ablation of the amygdala and the peri-hippocampal disconnection instead of amygdalohippocampectomy (AHC), which involves the removal of both structures. We previously reported the short-term results of AHCo, so we here present the long-term results (> 5 years of follow-up) of the patients operated on with AHCo.

METHOD

Since 2007, 35 patients (22 females) aged 20-61 years (mean: 42 years) were operated on with the AHCo technique, 17 patients on the left side and 18 on the right. Of these patients, 21 (14 females) have been followed up > 5 years (5 to 7.5 years, mean 6.5 years). We compare the present results with those observed shortly after surgery and with the patients operated on with AHC.

FINDINGS

In all 21 cases, the diagnosis was mesial temporal lobe sclerosis (histology confirmed in 20), 11 on the left side and 10 on the right. Epilepsy results after 5 years were good/very good in 18 patients (85.7%), with Engel class IA-B in 15 (71.4%) and II in 3 (14.3%), and bad in 3 patients, with Engel Class III in 2 (9.5%) and class IV in 1 (4.8%). Concerning morbidity, one patient had hemiparesis (hypertensive capsular hemorrhage 24 h after surgery), two verbal memory worsening, two quadrantanopia and three late depression that was reversed with medication. Comparatively, the AHC long-term results were 87% Engel class I, 8% Engel class II and 5% Engel class III-IV. The morbidity was equally small.

CONCLUSIONS

The good/very good results of AHCo 5 years after surgery are 86%, which is not distinct from the AHC results. So AHCo seems to be effective and potentially safer than AHC in long-term follow-up.

Intrachiasmatic abscess caused by IgG4-related hypophysitis

INTRODUCTION

Autoimmune hypophysitis is a rare disease of the pituitary, which may affect vision by inflammation and compression of the optic chiasm. However, intrachiasmatic abscess formation has not been previously reported.

METHODS

In this study, we report a case of a 29-year-old female with bitemporal hemianopia due to a cystic intrasellar tumor. The patient underwent surgical decompression of the lesion, which was found to be an intrachiasmatic abscess.

RESULTS

The histologic findings were consistent with IgG4 hypophysitis.

CONCLUSION

This rare clinical presentation suggests that in case of a disproportionate degree of visual impairment in relation to the size of the lesion, suspicion should lead to an intrachiasmatic lesion.

An atypical presentation of functional visual loss: A case report

RATIONALE

Functional visual loss (FVL) can manifest as various symptoms. Decreased distant visual acuity is the most common symptom and visual field defect is the second most common symptom. Hemianopsia is rarely reported. In an atypical situation of FVL, it is important to prove that no organic pathology exists, through detailed history taking and appropriate examinations.

PATIENT CONCERNS

This review presents the case of a 48-year-old male patient presented with decreased bilateral visual acuity and visual field defect after a traffic accident 3 weeks ago. Visual field test showed atypical features of FVL in which visual field change from binasal hemianopsia to left homonymous hemianopsia.

DIAGNOSIS

The best corrected visual acuities (BCVA) were 20/63 in both eyes and binasal hemianopsia was observed on a Humphrey visual field test. Brain computed tomography (CT) scan and magnetic resonance imaging (MRI) showed no abnormalities in the brain and optic chiasm. Two weeks after presentation, however, the patient's visual field defect changed from binasal hemianopsia to left homonymous hemianopsia. We diagnosed it as FVL due to conversion disorder.

INTERVENTION AND OUTCOMES

We decided to cooperate with a psychiatrist for cognitive behavioral therapy and the patient is under observation.

LESSONS

Binasal hemianopsia and homonymous hemianopsia are rare; however, it may occur simultaneously in 1 patient with FVL. The possibility of FVL should be considered when there is atypical visual field defect and no organic abnormalities are observed. Repeated Humphrey field test and VEP may be helpful in diagnosis of FVL.

Late emergence of macular sparing in a stroke patient: Clinical Case Report

RATIONALE

Occlusive cerebrovascular disease is the most common cause of homonymous hemianopia (HH) with macular sparing.

PATIENT CONCERNS

A 61-year-old man came to our ophthalmology clinic complaining of right-side hemianopia. Ophthalmic examination, visual field (VF) examination, and brain magnetic resonance imaging (MRI) were performed.

DIAGNOSES

He had right HH without macular sparing on the initial VF test. And brain MRI 6 days after the visual symptoms began revealed a left occipital infarction.

INTERVENTIONS AND OUTCOMES

Thirty-seven days after the onset, his follow-up 24-2 VF examination showed HH with bilateral macular sparing, which was not apparent in the initial VF examination. About 4 months after the stroke, his central 10-2 VF examination also showed HH with bilateral macular sparing.

LESSONS

We report a case of HH with a dramatic improvement in central vision several days after an occipital infarction. To our knowledge, this is the first case to show macular sparing developing after several days.

Homonymous Hemianopia and Vision Restoration Therapy

Homonymous hemianopia from stroke causes visual disability. Although some patients experience spontaneous improvement, others have limited to no change and may be left with a severe disability. Current rehabilitation strategies are compensatory and cannot restore function. Animal studies suggest that central nervous system plasticity could allow for redirection of lost visual function into undamaged areas of cortex. A commercial therapy system was developed, from which claims of visual field expansion were disputed by independent researchers. The treatment remains controversial with seemingly contradictory data being generated. Continued research is underway to demonstrate the (non-)efficacy of this treatment method.

Persistent lesion hyperintensity on brain diffusion-weighted MRI is an early sign of intravascular lymphoma

A 63-year-old man presented with right-sided hemianopia and unsteady gait. Brain MRI revealed multiple hyperintense infarct-like lesions on diffusion-weighted images (DWI). Hyperintensity persisted in some of these lesions even after 6 weeks, although his symptoms were ameliorated then. The patient developed episodic dizziness and a transient event of apraxia at 18 weeks after the first episode. Brain MRI revealed additional hyperintense lesions on DWI, which persisted even after 7 weeks. Eventually, the patient manifested cauda equina syndrome 39 weeks after the first episode. Brain MRI showed the presence of new lesions in addition to the persistent hyperintense lesions on DWI over 21 weeks in the right frontal lobe. Based on laboratory findings and the pathological assessment of bone marrow and random skin biopsies, the patient was diagnosed with intravascular lymphoma (IVL). Persistent hyperintense lesions on DWI of brain MRI may precede the clinical exacerbation of IVL.

Neural Substrates of Blindsight After Hemispherectomy

Blindsight is a visual phenomenon whereby hemianopic patients are able to process visual information in their blind visual field without awareness. Previous research demonstrating the existence of blindsight in hemianopic patients has been criticized for the nature of the paradigms used, for the presence of methodological artifacts, and for the possibility that spared islands of visual cortex may have sustained the phenomenon because the patients generally had small circumscribed lesions. To respond to these criticisms, the authors have been investigating for several years now residual visual abilities in the blind field of hemispherectomized patients in whom a whole cerebral hemisphere has been removed or disconnected from the rest of the brain. These patients have offered a unique opportunity to establish the existence of blindsight and to investigate its underlying neuronal mechanisms because in these cases, spared islands of visual cortex cannot be evoked to explain the presence of visual abilities in the blind field. In addition, the authors have been using precise behavioral paradigms, strict control for potential methodological artifacts such as light scatter, fixation, criterion effects, and macular sparing, and they have utilized new neuroimaging techniques such as diffusion tensor imaging tractography to enhance their understanding of the phenomenon. The following article is a review of their research on the involvement of the superior colliculi in blindsight in hemispherectomized patients. NEUROSCIENTIST 13(5):506—518, 2007.