James Sharpe's Contributions to Neurology and Neuro-ophthalmology: A Posthumous Tribute 10 Years On.

Dr. Sharpe was a leading eye movement researcher who had also been the editor of this journal. We wish to mark the 10th anniversary of his death by providing a sense of what he had achieved through some examples of his research.

Transient Visual Obscurations as the Presenting Symptom of Papilledema from COVID-19-Related Cerebral Venous Sinus Thrombosis.

Coronavirus disease-19 (COVID-19) patients are at an increased risk of cerebral venous sinus thrombosis (CVST). Rapid diagnosis and treatment are vital to ensure a favorable outcome for CVST, so clinicians need to be aware of all its potential presentations. We describe a unique case where transient visual obscurations (TVOs) from papilledema were the presenting symptoms of COVID-19-related CVST. A 43-year-old woman, who had tested positive for severe acute respiratory syndrome coronavirus-2 1 month earlier, developed holocephalic headache, TVOs, and bilateral disc edema. She did not seek medical attention until she developed TVOs. Visual acuity was 20/20 and Humphrey visual field testing showed enlarged blind spots in both eyes. She was diagnosed with papilledema and underwent magnetic resonance imaging and magnetic resonance venography of the brain, which revealed right transverse sinus thrombosis. Lumbar puncture was performed, showing elevated opening pressure and normal cerebrospinal fluid contents. Her optic disc edema resolved and visual function remained normal 6 weeks following warfarin and topiramate therapy. Recanalization of the right transverse sinus occurred after 3 months. Although rare, TVOs are important presenting symptoms of COVID-19-related CVST. Ophthalmologists, who may be the first physicians to assess patients with this presentation, should be aware of TVOs as potential presenting symptoms of CVST, so diagnoses can be made in a timely manner.

Vision therapy: Occlusion, prisms, filters, and vestibular exercises for mild traumatic brain injury.

A number of treatment approaches have been advocated for persistent visual complaints following mild traumatic brain injury. These include devices such as binasal occlusion, yoked prisms, vertical prisms, and filters, as well as vestibular training. We discuss the rationale and the evidence for each of these approaches. Binasal occlusion has been advocated for visual motion sensitivity, but it is not clear why this should help, and there is no good evidence for its symptomatic efficacy. Base-in prisms can help manage convergence insufficiency, but there are few data on their efficacy. Midline shift is an unproven concept, and while the yoked prisms advocated for its treatment may have some effect on egocentric neglect, their use in mild traumatic brain injury is more questionable. A wide variety of posttraumatic symptoms have been attributed to vertical heterophoria, but this is an unproven concept and there are no controlled data on the use of vertical prisms for mild traumatic brain injury symptoms. Filters could plausibly ameliorate light intolerance but studies are lacking. Better evidence is emerging for the effects of vestibular therapy, with a few randomized controlled trials that included blinded assessments and appropriate statistical analyses. Without more substantial evidence, the use of many of these techniques cannot be recommended and should be regarded as unproven and in some cases implausible.

Vision Therapy: Ocular Motor Training in Mild Traumatic Brain Injury.

Vision therapy in the form of ocular motor training is increasingly used to treat visual complaints, particularly in the setting of persistent symptoms after mild traumatic brain injury (mTBI). In this review, we discuss the rationale behind this intervention and the evidence for its utility. Although the efficacy of exercises for primary convergence insufficiency is plausible and supported by data, there is not yet strong evidence of benefit for the post-traumatic variant. It is not established that abnormalities in fixation, pursuit, and saccades in mTBI are the cause of post-concussive symptoms, or that these abnormalities arise from ocular motor damage rather than being secondary effects of cognitive problems with attention or executive control. The few studies to date have significant methodological weaknesses. More substantial evidence is required before vision therapy can be accepted as a useful tool in the rehabilitation of patients with brain trauma. ANN NEUROL 2020;88:453-461.

The use of real-time image stabilization and augmented reality eyewear in the treatment of oscillopsia.

OBJECTIVES/HYPOTHESIS: The symptom of oscillopsia in patients with bilateral vestibular loss (BVL) can be reduced as dynamic visual acuity (DVA), the reduction in visual acuity during head movement, is improved by using real-time image stabilization, delivered by augmented reality eyewear. SETTING: Tertiary multidisciplinary neurotology clinic. STUDY DESIGN: Prospective experimental study. METHODS: Immersive virtual reality glasses used in combination with a compact digital video camera were used. A software algorithm was developed that used a center-weighted Lucas-Kanade optical flow method to stabilize video in real time. Six patients with BVL were tested for changes in DVA using the eyewear. The ability to read a Snellen chart during a 2-Hz oscillating head rotation DVA test was measured. RESULTS: For combined scores of vertical and horizontal head rotations, the mean number of lines readable at rest was 7.86, which dropped to 2.77 with head movement (a combination of vertical and horizontal perturbations). This increased to a mean of 6.14 lines with the image stabilization software being activated. This difference was statistically significant (P < .001). CONCLUSION: This is the first successful attempt to improve dynamic visual acuity in patients with bilateral vestibular loss. Recent hardware upgrades are promising in improving these results even further.

Double impairment: clinical identification of 33 cases of cerebellar ataxia with bilateral vestibulopathy.

OBJECTIVE: Following recently described small series of patients with the syndrome of cerebellar ataxia with bilateral vestibulopathy (CABV), the authors undertook a careful clinical and laboratory assessment of patients who presented to their unit with characteristics of this syndrome. STUDY DESIGN: Case note review. SETTING: Tertiary, university-based, multidisciplinary neurootology clinic. SUBJECTS: Thirty-three patients whose characteristics fit this syndrome. METHODS: Patients presenting to the Multidisciplinary Neurotology Clinic with characteristics of CABV were entered into a bespoke database. This was analyzed to identify the clinical findings and results of vestibular investigations for this group. RESULTS: Patients presented at a mean age of 54 years (SD, 17.6) with symptoms having been present for a median of 3 years (interquartile ratio, 2.0-9.5). Caloric testing greatly underestimated the disorder, being subnormal in only 18% of patients; the head-thrust test was abnormal and dynamic visual acuity testing was abnormal 88% and 91% of the time, respectively. Of the patients, 76% demonstrated gaze-evoked nystagmus. Impaired smooth pursuit (97% of patients showed low gain with saccadic corrections) and impaired cancellation of the vestibulo-ocular reflex (in 97% of patients) were found. Impaired saccular otolithic function was abnormal in 33%, adding to patient imbalance. CONCLUSION: The unique double-pathway balance impairment in CABV patients causes a high prevalence of subnormal function of both central and peripheral vestibular function. This is an easily missed clinical entity that is often associated with normal caloric investigations. As many patients with this syndrome are poor candidates for vestibular rehabilitation therapy, resources are better devoted to the early implementation of assistance with their safe ambulation and activities of daily living.