Herpes zoster in neuro-ophthalmology: a practical approach.

Herpes Zoster (HZ) or shingles is the reactivation of the Varicella Zoster Virus (VZV), usually along a single sensory nerve, but can affect both sensory and motor cranial nerves. Major risk factors for HZ include immunosuppressed status and age older than 60 years. In the United States, the lifetime risk of HZ is approximately 30%. Worldwide, the median incidence of HZ is 4-4.5 per 1000 person-years across the Americas, Eurasia, and Australia. HZ ophthalmicus, occurring in 10-20% of patients, is an ophthalmic emergency characterized by VZV reactivation along the V1 branch of the trigeminal nerve. Approximately half of this patient subgroup will go on to develop ocular manifestations, requiring prompt diagnosis and management. While anterior segment complications are more common, neuro-ophthalmic manifestations are rarer and can also occur outside the context of overt HZ ophthalmicus. Neuro-ophthalmic manifestations include optic neuropathy, acute retinal necrosis or progressive outer retinal necrosis, cranial neuropathy (isolated or multiple), orbitopathy, and CNS manifestations. Although typically a clinical diagnosis, diagnosis may be aided by neuroimaging and laboratory (e.g., PCR and serology) studies. Early antiviral therapy is indicated as soon as a presumptive diagnosis of VZV is made and the role of corticosteroids remains debated. Generally, there is wide variation of prognosis with neuro-ophthalmic involvement. Vaccine-mediated prevention is recommended. In this review, we summarize neuro-ophthalmic manifestations of VZV.

Subfoveal Choroidal Neovascular Membrane Secondary to Idiopathic Intracranial Hypertension.

Purpose: To present a rare case of subfoveal choroidal neovascular membrane (CNVM) secondary to idiopathic intracranial hypertension. Methods: A case was evaluated. Results: A 21-year-old woman presented with a 2-week history of painless blurred vision in the right eye. She described initial metamorphopsia and intermittent bitemporal headaches lasting 30 minutes. She denied pain with eye movements and a history of trauma. Her body mass index was 49 kg/m2. The visual acuity (VA) was 20/320 OD and 20/20 OS; there was no relative afferent pupillary defect. A dilated fundus examination showed bilateral optic disc edema and a subfoveal CNVM in the right eye. The patient was started on oral acetazolamide 500 mg twice daily and treated with 2 intravitreal antivascular endothelial growth factor (anti-VEGF) injections. Three months later, the VA was 20/30 in the right eye and the disc edema had improved. Conclusions: CNVMs in the setting of idiopathic intracranial hypertension-related papilledema may be subfoveal and have an excellent response to anti-VEGF agents.

Assessment of Reversibility of Transverse Venous Sinus Stenosis in Patients With Papilledema.

BACKGROUND: Bilateral transverse venous sinus stenosis (TVSS) or stenosis of a dominant venous sinus has been found to be very sensitive radiological findings in patients with intracranial hypertension (IH), yet there is still an ongoing debate whether they constitute reversible or permanent phenomena. Thus, the purpose of this study was to investigate the reversibility of TVSS in patients with IH, including conservatively treated patients with signs of IH as defined by the presence of papilledema. METHODS: This was a retrospective chart review of all patients diagnosed with IH between 2016 and 2022, assessed from 2 tertiary university-affiliated neuro-ophthalmology practices. Inclusion criteria were the presence of papilledema, as quantified by optical coherence tomography, and bilateral TVSS, which is considered typical of IH on neuroimaging. During follow-up, included patients must have had confirmation of papilledema resolution as well as subsequent neuroimaging after conservative treatment or cerebrospinal fluid flow diversion. Patients with dural sinus vein thrombosis or intrinsic stenosis from sinus trabeculations or significant arachnoid granulations were excluded from the study. Either CT venography or MRI/MR venography was reviewed by a fellowship-trained neuroradiologist, and the degree of stenosis was scored through the combined conduit score (CCS), as described by Farb et al. The primary outcome was to assess TVSS changes after resolution or improvement of papilledema. RESULTS: From 435 patients, we identified a subset of 10 who satisfied all inclusion criteria. Our cohort comprised entirely women with a median age of 29.5 years and a median BMI of 32.5 kg/m2. Treatment consisted of acetazolamide in 7 patients, of which 1 had additional topiramate and 2 underwent cerebrospinal fluid flow diversion. Furthermore, 6 patients demonstrated significant weight loss during follow-up. For the primary outcome, 5 of 10 patients exhibited no appreciable TVSS change, and 5 patients demonstrated significant improvement in TVSS, of which 4 received conservative treatment only. Papilledema resolution or improvement was statistically significantly associated with increasing average CCS, TVSS diameter, and grade. CONCLUSIONS: We were able to demonstrate that TVSS can be both irreversible and reversible in patients with resolved papilledema. The finding of TVSS reversibility from conservative treatment alone is novel and has important implications to optimize patient care. Future studies should work to identify factors associated with irreversible TVSS for subsequent targeted intervention and prevention.

The Leading Causes of Optic Disc Edema Seen in Tertiary Care, Academic Neuro-Ophthalmology Clinics.

BACKGROUND: Optic disc edema (ODE) is one of the most common reasons for referral to a neuro-ophthalmologist. There are various causes that require vastly different workup. Thus, differentiating among each cause is important. Our goal was to determine the causes of ODE and various clinical characteristics of consecutive patients with ODE presenting to neuro-ophthalmology clinics. METHODS: A retrospective review of consecutive patients with ODE over a period of 5 years were included. Fundus photographs were routinely obtained as part of clinical care. Clinical data including retinal nerve fiber layer thickness, best-corrected visual acuity, and visual field mean deviation were retrieved, and patients were grouped by etiology. RESULTS: A total of 654 patients (n = 462 or 70.6% women and 192 or 29.4% men) with ODE were included with a mean age of 41.2 ± 17.9 years. Female patients were significantly younger than male patients (mean age female participants: 38.7 years, male participants: 47.6; P < 0.001). The top 5 most common causes of ODE in our clinics were idiopathic intracranial hypertension (IIH; 351/654 or 53.7%), nonarteritic anterior ischemic optic neuropathy (NAION; 116/654 or 17.4%), non-IIH papilledema (71/654 or 10.9%), optic neuritis (ON; 46/654 or 7.0%), and uveitis (17/654 or 2.6%). When considering female-only patients, the top 3 causes of ODE were IIH, non-IIH papilledema, and NAION. Among male-only patients, the top 3 causes were NAION, IIH, and non-IIH. Among the top 5 causes of ODE, visual acuity was the worst at presentation in the ON group and the best in the patients with IIH. The Humphrey mean deviation was the worst in ON/NAION groups and best in IIH group. The ODE was most severe in patients with non-IIH papilledema and least severe in ON group. Non-IIH patients with papilledema were not significantly different in visual acuity and visual field parameters at presentation compared with patients with IIH papilledema. Patients with papilledema (both IIH and non-IIH etiologies) had significantly better visual function at presentation compared with other top causes of disc edema (P < 0.001). CONCLUSIONS: The most common cause of ODE seen in neuro-ophthalmology clinics was IIH, and these patients were more likely to present with preserved visual function. The higher prevalence of IIH was likely why most patients with ODE were women. Visual function at presentation was not able to differentiate the specific cause of papilledema; however, it was an important differentiating factor for all papilledema cases compared with all other causes of ODE including ON and NAION.

Utility of ChatGPT for Automated Creation of Patient Education Handouts: An Application in Neuro-Ophthalmology.

BACKGROUND: Patient education in ophthalmology poses a challenge for physicians because of time and resource limitations. ChatGPT (OpenAI, San Francisco) may assist with automating production of patient handouts on common neuro-ophthalmic diseases. METHODS: We queried ChatGPT-3.5 to generate 51 patient education handouts across 17 conditions. We devised the "Quality of Generated Language Outputs for Patients" (QGLOP) tool to assess handouts on the domains of accuracy/comprehensiveness, bias, currency, and tone, each scored out of 4 for a total of 16. A fellowship-trained neuro-ophthalmologist scored each passage. Handout readability was assessed using the Simple Measure of Gobbledygook (SMOG), which estimates years of education required to understand a text. RESULTS: The QGLOP scores for accuracy, bias, currency, and tone were found to be 2.43, 3, 3.43, and 3.02 respectively. The mean QGLOP score was 11.9 [95% CI 8.98, 14.8] out of 16 points, indicating a performance of 74.4% [95% CI 56.1%, 92.5%]. The mean SMOG across responses as 10.9 [95% CI 9.36, 12.4] years of education. CONCLUSIONS: The mean QGLOP score suggests that a fellowship-trained ophthalmologist may have at-least a moderate level of satisfaction with the write-up quality conferred by ChatGPT. This still requires a final review and editing before dissemination. Comparatively, the rarer 5% of responses collectively on either extreme would require very mild or extensive revision. Also, the mean SMOG score exceeded the accepted upper limits of grade 8 reading level for health-related patient handouts. In its current iteration, ChatGPT should be used as an efficiency tool to generate an initial draft for the neuro-ophthalmologist, who may then refine the accuracy and readability for a lay readership.

Sensitivity of Magnetic Resonance Imaging of the Medial Longitudinal Fasciculus in Internuclear Ophthalmoplegia.

BACKGROUND: Internuclear ophthalmoplegia (INO) is a result of insult to the medial longitudinal fasciculus (MLF). Clinicoradiological correlation in patients with INO has been reported to be poor; however, prior studies have used low resolution MRI imaging techniques and included patients with subclinical INO. We aimed to determine the sensitivity of modern MRI interpreted by a specialist neuroradiologist to detect clinically evident INO. METHODS: A retrospective chart review of patients in 2 tertiary University-affiliated neuro-ophthalmology practices with the diagnosis of INO. MRI scans of all patients were reviewed and interpreted by a fellowship-trained neuroradiologist for the presence of lesion in MLF and concordance with the original imaging report. RESULTS: Forty-five patients were included in the study: 33 with demyelinating disease, 11 with stroke, and 1 with intracranial mass. A visible MLF lesion was present in 25/33 demyelinating cases and 7/11 ischemic cases. Lesions in 2 cases in each group were identified only after review by a fellowship-trained neuroradiologist. In demyelinating INO, patients with a visible MLF lesion were more likely to show other brainstem (72%) and supratentorial (51%) white matter lesions. CONCLUSIONS: In 25% of patients with demyelinating INO and 33% of patients with ischemic INO, no visible lesion was identified on current high-quality MRI imaging. Review of imaging by a neuroradiologist increased the possibility of lesion been identified.

Ensemble of deep convolutional neural networks is more accurate and reliable than board-certified ophthalmologists at detecting multiple diseases in retinal fundus photographs.

AIMS: To develop an algorithm to classify multiple retinal pathologies accurately and reliably from fundus photographs and to validate its performance against human experts. METHODS: We trained a deep convolutional ensemble (DCE), an ensemble of five convolutional neural networks (CNNs), to classify retinal fundus photographs into diabetic retinopathy (DR), glaucoma, age-related macular degeneration (AMD) and normal eyes. The CNN architecture was based on the InceptionV3 model, and initial weights were pretrained on the ImageNet dataset. We used 43 055 fundus images from 12 public datasets. Five trained ensembles were then tested on an 'unseen' set of 100 images. Seven board-certified ophthalmologists were asked to classify these test images. RESULTS: Board-certified ophthalmologists achieved a mean accuracy of 72.7% over all classes, while the DCE achieved a mean accuracy of 79.2% (p=0.03). The DCE had a statistically significant higher mean F1-score for DR classification compared with the ophthalmologists (76.8% vs 57.5%; p=0.01) and greater but statistically non-significant mean F1-scores for glaucoma (83.9% vs 75.7%; p=0.10), AMD (85.9% vs 85.2%; p=0.69) and normal eyes (73.0% vs 70.5%; p=0.39). The DCE had a greater mean agreement between accuracy and confident of 81.6% vs 70.3% (p<0.001). DISCUSSION: We developed a deep learning model and found that it could more accurately and reliably classify four categories of fundus images compared with board-certified ophthalmologists. This work provides proof-of-principle that an algorithm is capable of accurate and reliable recognition of multiple retinal diseases using only fundus photographs.

Prevalence of Person-First Language in Idiopathic Intracranial Hypertension: A Systematic Review of Case Reports.

BACKGROUND: Person-first language (PFL) is a linguistic prescription, which places a person before their disease. It is considered an important tool to reduce stigma. However, PFL is not routinely used across the scientific literature, particularly in patients with overweight or obesity. Patients with idiopathic intracranial hypertension (IIH) face various stigmas through high rates of poverty, female gender, and frequent rates of comorbidities. Non-PFL language use intersects and worsen the health inequities faced by these patients. METHODS: A systematic review of case reports. MEDLINE and EMBASE were searched for all case reports with "pseudotumor cerebri" [MESH] OR "Idiopathic Intracranial Hypertension" as key word between January 1974 and August 2022. The primary criterion was the article's inclusion of patients with overweight or obesity. The secondary criterion was the article's discussion regarding obesity as risk factor. Articles not meeting primary or secondary criteria were excluded. RESULTS: Approximately 514/716 (71.8%) articles used non-PFL language. The publication year was predictive of non-PFL language: 1976-1991 (82.3%) vs 1992-2007 (72.3%, P = 0.0394) and 2008-2022 (68.3%, P = 0.0056). Non-PFL was significantly higher in obesity compared with other medical conditions (60.3% vs 7.3%, P < 0.001). The patient gender (P = 0.111) and ethnicity (P = 0.697), author's specialty (P = 0.298), and primary English-speaking status (P = 0.231), as well as the journal's impact factor (P = 0.795), were not predictive of non-PFL. CONCLUSIONS: Most literature focused on IIH use non-PFL when discussing overweight or obesity, regardless of the patient's gender and ethnicity, journal's impact factor, senior author's specialty, and English-speaking status. Non-PFL use is much more common when discussing obesity compared with other medical conditions. Appropriate use of PFL can decrease stigma and, more importantly, decrease the intersectionality of health stigma faced by patients with IIH.

The Causes of Optic Disc Edema in Patients Presenting With Significantly Compromised Vision.

BACKGROUND: To evaluate the most common causes of optic disc edema (ODE) in patients with significantly compromised vision (initial best-corrected visual acuity [BCVA] of 20/400 or worse) at presentation. METHODS: Retrospective chart review over a 5-year period of consecutive patients presenting to tertiary neuro-ophthalmology clinics at the University of Toronto. RESULTS: A total of 656 patients with ODE were included, and 49 patients (7.47%) had an initial BCVA of 20/400 or worse. There were 54 eyes included at baseline and 49 eyes at final follow-up. There were 29 female and 20 male patients. The mean age at first visit across patients was 55.9 years. Female patients (n = 29) were significantly older than male patients (n = 20) (P < 0.05). The causes of ODE were optic neuritis (ON) (n = 22; 40.7%), nonarteritic anterior ischemic optic neuropathy (NAION) (n = 22; 40.7%), arteritic anterior ischemic optic neuropathy (AAION) (n = 5; 9.26%), uveitis-related (n = 3; 5.56%), papilledema from idiopathic intracranial hypertension (IIH) (n = 1; 1.85%), and Vogt-Koyanagi-Harada disease (n = 1; 1.85%). Initial BCVA was not significantly different between ON and NAION groups (P = 0.52); however, final BCVA was significantly better in the ON group (P < 0.0001). The mean initial BCVA was worst in the AAION group (2.62 ± 0.54 logarithm of the minimum angle of resolution). The most common cause of ODE in patients <40 years old was ON (83.3%), whereas the 2 most common causes in patients >80 were NAION (60%) and AAION (40%). In patients between the ages of 60-80, NAION (100%) was the only cause. CONCLUSIONS: Patients with ODE and poor vision at presentation represent a minority of cases seen in neuro-ophthalmology clinics (<10%). Optic neuritis and NAION are the 2 most common causes of ODE with poor vision at presentation. These findings are limited by a small sample size and potential sampling bias.

Evaluating smartphone fundoscopy as a pedagogical tool in medical education: a narrative review.

Direct ophthalmoscopy continues to be the "gold standard" method for retinal and optic nerve evaluation despite known challenges for learners to acquire this clinical skill and minimal opportunities for patient-facing practice. Here we review current literature regarding smartphone fundoscopy (SF) as an alternative learning tool that remains underutilized in Canadian medical schools. SF has significant advantages over direct ophthalmoscopy, such as enhanced learner visualization of ocular structure and pathologies, greater learner usability in comparison, and improved fundus assessment during more difficult ocular examinations such as with pediatric patients. Furthermore, SF provides opportunities for instructor exchange and feedback, group learning, increased learner confidence, and most important, an improved patient experience. Yet challenges remain with SF, including patient confidentiality during data capture and sharing and meaningful integration into an already limited and saturated curriculum. Our review finds SF to be a pedagogic tool with the potential to reinvigorate fundoscopy learning to improve competency in this important clinical skill.

Anemia and idiopathic intracranial hypertension: a prospective study.

BACKGROUND: Anemia has been temporally associated with idiopathic intracranial hypertension (IIH), but the relationship is uncertain because of a lack of prospective studies and because both IIH and anemia are common in young women with obesity. DESIGN AND METHODS: This was a prospective study of consecutive patients with IIH referred to 3 neuro-ophthalmology centres between March 2021 and September 2022. All patients had a complete blood count available within 6 months of presentation. Anemia was defined as mild (110-120 g/L), moderate (80-109 g/L), and severe (<80 g/L). RESULTS: Of 143 patients, 113 had normal hemoglobin (group 1) and 30 had anemia (group 2). In group 2, the anemia was defined as mild (15 of 30; 50.0%), moderate (11 of 30; 36.7%), and severe (4 of 30; 13.3%). There was no difference in female sex (105 of 113 vs 29 of 30; p = 0.453), age (31.5 ± 9.2 years vs 28.5 ± 10.3 years; p = 0.144), and body mass index (35.2 ± 6.9 kg/m2 vs 38.0 ± 8.1 kg/m2; p = 0.111). Groups 1 and 2 did not differ in visual acuity (0.04 ± 0.09 logMAR vs 0.07 ± 0.14 logMAR; p = 0.377), retinal nerve fibre layer thickness (174.5 ± 68.4 µm vs 206.5 ± 97.0 µm; p = 0.098), mean deviation (-3.2 ± 3.1 dB vs -3.9 ± 3.4 dB; p = 0.180), and the need for medical (34 of 113 vs 8 of 30; p = 0.715) or surgical treatment (3 of 113 vs 3 of 30; p = 0.074). Patients with moderate to severe anemia were more likely to require surgical therapy (2 of 15 vs 3 of 113; p = 0.045). CONCLUSION: Approximately 1 of every 5 patients with IIH has anemia, and this is severe in >10% of patients. Patients with moderate and severe anemia may require more invasive surgical treatment. Given the high incidence of anemia and the availability of a complete blood count, we recommend that this test be obtained for all patients with suspected IIH.

Left Superior Homonymous Quadrantanopia due to Giant Virchow-Robin Space.

A 51-year-old man was referred by his optometrist for an incidental finding of a visual field defect. Humphrey 24-2 SITA-Fast visual field testing revealed a left superior homonymous quadrantanopia, and magnetic resonance imaging of the brain showed a 2.0 × 0.5-cm oblong-shaped cerebrospinal fluid space posterior to the right basal ganglia. This space coursed close to the lateral geniculate body and was thought to represent a giant perivascular (Virchow-Robin) space. This case demonstrates that patients with a visual field defect without other neurological symptoms could be a result of an enlarged Virchow-Robin space along the visual pathway.

Preservation of Vision after Early Recognition of Anterior Ischemic Optic Neuropathy in a Patient with Sepsis.

Non-arteritic ischemic optic neuropathy (NAION) can rarely occur in the setting of sudden vascular compromise, especially in patients with a "disk-at-risk" appearance. Anemia and hypotension are believed to be the main precipitators of shock-induced NAION. Early recognition of this phenomenon can prevent further visual loss and result in partial visual recovery. We here present a 56-year-old patient who developed NAION characterized by optic disc edema in both eyes and visual loss in the left eye secondary to hypotension in the setting of septic shock. He received aggressive blood pressure management (stopping all his anti-hypertensives, hydration, and midrodrine) which resulted in stabilization of vision in the right eye and likely prevented further visual loss in the left eye.

Maculopathies Referred to Neuro-Ophthalmology Clinic as Optic Neuropathies: A Case Series.

BACKGROUND: The clinical features of maculopathies and optic neuropathies often overlap: Both present with decreased visual acuity and variable loss of color vision; thus, maculopathy can be misdiagnosed as optic neuropathy, leading to patient harm. We aimed to determine what findings and/or tests were most helpful in differentiating between optic neuropathy and maculopathy. METHODS: A retrospective chart review of consecutive patients over 4.5 years who were referred to neuro-ophthalmology clinics with the diagnosis of optic neuropathy but whose final diagnosis was maculopathy. Patient demographics, mode of presentation, clinical profile, complete ophthalmological examination, results of all ancillary testing, and final diagnosis were recorded. RESULTS: A total of 47 patients (27 women) were included. The median age was 55 years (range, 18-85). Most referrals were by ophthalmologists (72.3%) and optometrists (12.8%). The diagnosis of maculopathy was made in 51.1% of patients at the time of first neuro-ophthalmic consultation. Only 6.4% patients (3) had relative afferent pupillary defect. Benign disc anomalies (tilted, myopic, small, or anomalous discs) were present in 34.0%, and 21.3% had pathologic disc changes unrelated or secondary to maculopathy. Macular ocular coherence tomography (OCT) was abnormal in 84.4% (with outer retinal pathology in 42.2% and inner retina pathology in 17.8%). Retinal nerve fiber layer (RNFL) thickness was normal in 82.6% of patients. CONCLUSIONS: Macular OCT is a high-yield test in differentiating between optic neuropathy and maculopathy and should be obtained in patients with suspected optic neuropathies who have normal RNFL thickness. Macular dystrophies, particularly cone dystrophies, unspecified retinal disorders, and macular degeneration were the most common mimics of optic neuropathy. The diagnosis was often present on OCT of the macula. The presence of coexistent benign and pathological disc anomalies may lead to maculopathy being misdiagnosed as optic neuropathy.