Reexamining the Incidence of Nonarteritic Anterior Ischemic Optic Neuropathy: A Rochester Epidemiology Project Study.

BACKGROUND: This study aims to determine the population-based incidence and characterize the features of nonarteritic anterior ischemic optic neuropathy (NAION) using the Rochester Epidemiology Project (REP). METHODS: All patients diagnosed with an optic neuropathy from January 1, 1990, to December 31, 2016, were retrospectively reviewed to identify incident cases of NAION using the REP database, which is a record-linkage system of medical records for all patient-physician encounters among Olmsted County, Minnesota residents. The overall incidence of NAION was estimated using the age-specific and sex-specific population figures for Olmsted County census data for 1990 through 2016. Visual outcomes and risk factors were evaluated. The systemic risk factors were compared with age-matched controls. RESULTS: One hundred four patients were diagnosed with NAION during the 26-year study period. The overall age and sex adjusted incidence was 3.89 per 100,000 individuals (95% confidence interval [CI]: 3.14-4.65). The incidence was 7.73 (CI: 6.24-9.22) in patients aged 40 years or older and 10.19 (CI: 8.15-12.23) in patients aged 50 years or older. Median age at diagnosis was 65 years (range, 40-90 years), and 59 (56.7%) were male. The median logMAR visual acuity at presentation was 0.35 (Snellen equivalent of 20/40) with 14 patients (13.5%) having vision of counting fingers or worse. Among the 91 patients with final visual acuity outcome data available, the median visual acuity was 0.40 (Snellen equivalent of 20/50) with 12 patients (13.2%) having vision of counting fingers or worse. Twenty-four patients (26.4%) were noted to have final acuity at least 3 Snellen lines worse than at presentation, whereas 17 patients (18.7%) were noted to improve by at least 3 lines. The median mean deviation on automated visual field testing was -10.2 dB at presentation and -11.1 dB at follow-up. Twenty-two patients (21.2%) suffered NAION in the fellow eye; the median interval between involvement of the first and second eyes was 1.39 years. Systemic diseases present in the NAION cohort included hypertension (79.8%), diabetes mellitus (39.4%), obstructive sleep apnea (23.1%), and hyperlipidemia (74.0%), which were all statistically higher than age-matched controls. CONCLUSIONS: NAION is a relatively common optic neuropathy in elderly patients with vascular risk factors. Our data indicate that the incidence of NAION has remained relatively stable in the population of Olmsted County over the past 4 decades.

Ophthalmologic Involvement in Adults with Histiocytic Disorders: Clinical Presentation and Treatment Outcomes.

PURPOSE: To evaluate the clinical presentation, treatment, and outcomes in adult patients with histiocytic disorders with ocular, orbital, optic nerve, or cavernous sinus involvement. DESIGN: Observational, retrospective chart review. PARTICIPANTS: Adult patients (age ≥ 18 years) at Mayo Clinic from January 1, 1996, to July 1, 2021, with histiocytic disorders. Inclusion criteria were (1) histiocytic disorder by biopsy and appropriate clinical phenotype; (2) available medical records; and (3) ocular, orbital, optic nerve, or cavernous sinus involvement. METHODS: Retrospective chart review. MAIN OUTCOME MEASURES: Response to therapy, measured in clinical and radiographic impact. RESULTS: Thirty-two patients were identified: 7 with Langerhans cell histiocytosis (LCH); 15 with Erdheim-Chester disease (ECD); 1 with mixed LCH/ECD phenotype; 8 with Rosai-Dorfman disease (RDD); and 1 with mixed RDD/ECD phenotype. Ophthalmologic involvement was part of the initial presentation in 69% of patients (22/32). Eyelid edema (13/32, 41%) and proptosis (12/32, 38%) were the most frequent presentations. Isolated orbital or cavernous sinus involvement was present in 3 of 7 patients with LCH and 1 of 8 patients with RDD. Optic nerve sheath involvement was present in 2 of 7 LCH patients, 14 of 15 ECD patients, and 1 RDD/ECD patient. Diffuse (> 75%) orbital involvement was seen in 12 of 15 ECD patients and 1 of 7 LCH patients. Ocular involvement was seen in 1 of 15 ECD patients, 6 of 8 RDD patients, and 1 of 1 mixed RDD/ECD patient. The cavernous sinuses were involved in 1 of 7 LCH patients, 5 of 15 ECD patients, and both mixed phenotype patients. Visual acuity was affected in 14 patients (14/24, 58%) with a median logarithm of the minimum angle of resolution visual acuity of 0.1 (range, -0.12 to 3). BRAF V600E mutations were found in 75% (3/4) of LCH patients and 91% (10/11) of ECD patients. Patients received a variety of treatment, and response was variable across disease types. CONCLUSIONS: Orbital involvement was more commonly seen in LCH and ECD, whereas ocular involvement was more common in RDD. Visual acuity may be impacted from ocular involvement or compression of the optic nerve with diffuse orbital involvement.

Longitudinal Retinal Changes in MOGAD.

OBJECTIVE: Patients with myelin oligodendrocyte glycoprotein antibody (MOG-IgG)-associated disease (MOGAD) suffer from severe optic neuritis (ON) leading to retinal neuro-axonal loss, which can be quantified by optical coherence tomography (OCT). We assessed whether ON-independent retinal atrophy can be detected in MOGAD. METHODS: Eighty patients with MOGAD and 139 healthy controls (HCs) were included. OCT data was acquired with (1) Spectralis spectral domain OCT (MOGAD: N = 66 and HCs: N = 103) and (2) Cirrus high-definition OCT (MOGAD: N = 14 and HCs: N = 36). Macular combined ganglion cell and inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) were quantified. RESULTS: At baseline, GCIPL and pRNFL were lower in MOGAD eyes with a history of ON (MOGAD-ON) compared with MOGAD eyes without a history of ON (MOGAD-NON) and HCs (p < 0.001). MOGAD-NON eyes had lower GCIPL volume compared to HCs (p < 0.001) in the Spectralis, but not in the Cirrus cohort. Longitudinally (follow-up up to 3 years), MOGAD-ON with ON within the last 6-12 months before baseline exhibited greater pRNFL thinning than MOGAD-ON with an ON greater than 12 months ago (p < 0.001). The overall MOGAD cohort did not exhibit faster GCIPL thinning compared with the HC cohort. INTERPRETATION: Our study suggests the absence of attack-independent retinal damage in patients with MOGAD. Yet, ongoing neuroaxonal damage or edema resolution seems to occur for up to 12 months after ON, which is longer than what has been reported with other ON forms. These findings support that the pathomechanisms underlying optic nerve involvement and the evolution of OCT retinal changes after ON is distinct in patients with MOGAD. ANN NEUROL 2022;92:476-485.

Transient Bilateral Central Scotoma on Awakening: A Distinct Phenomenon.

BACKGROUND: Transient vision loss can be an alarming symptom owing to potentially serious etiologies such as thromboembolism or giant cell arteritis. Transient monocular vision loss (TVML) on awakening has been recently described as a benign phenomenon (Bouffard et al, 2017). Our objective was to describe the unique phenomenon of transient binocular vision loss (TBVL) on awakening. METHODS: Retrospective observational case series of 5 patients who experienced TBVL on awakening seen in the neuro-ophthalmology clinic at the Mayo Clinic between 2016 and 2020. Patients who described generalized blurred vision and those with monocular transient vision loss were excluded. RESULTS: The median age was 81.4 years (range, 68-92 years), and all were male. Every patient described a stereotyped transient bilateral central scotoma on awakening with slightly irregular borders and mild asymmetry between the 2 eyes lasting between 15 and 90 minutes. Frequency ranged from 3 to 7 times per week, and there was a median of 319 episodes (range, 126-728 episodes) before evaluation in the neuro-ophthalmology clinic. All patients had normal optic nerves, and no plaques were noted in the retinal vessels. All 5 had macular drusen, which were predominantly extrafoveal and mild. Two patients underwent electrophysiology testing, which were both normal on full-field electroretinogram (ERG), but there was blunted central wave forms on multifocal ERG. Two patients underwent dark adaptation testing, which showed both prolong and diminished dark adaptation. Neuroimaging and thromboembolic workup were unrevealing. CONCLUSIONS: TBVL is a distinct phenomenon from TMVL on awakening, which has a different demographic and symptomology. The etiology is unclear but seems to be a focal macular process in conjunction with an autoregulatory failure resulting in a supply-demand mismatch during low-light conditions.

Evaluating the Incidence and Neuro-Ophthalmic Manifestations of Carotid-Cavernous Fistulas.

BACKGROUND: To determine the incidence of carotid-cavernous fistula (CCF) and describe the neuro-ophthalmic manifestations and eventual clinical outcomes. METHODS: This was a population-based, retrospective cohort study using the Rochester Epidemiology Project to identify patients aged 18 years or older residing in Olmsted County, MN, diagnosed with CCF from 1997 to 2019. The medical records were reviewed for ophthalmic signs and symptoms, including conjunctival chemosis, proptosis, orbital bruit, diplopia, ophthalmoplegia, orbital pain, ocular hypertension, and blurred vision. Also determined was the number of patients with CCF found incidentally on neuroimaging, without clinical manifestations. RESULTS: Ten patients were diagnosed with a CCF between 1997 and 2019 with an overall incidence rate of 0.37 per 100,000 per year (95% CI 0.20-0.68). The median age was 50.5 years (range 23-74 years), 6 (60%) were female, and 9 were White and 1 patient was Korean. Three patients (30%) were asymptomatic and found incidentally on imaging that was obtained for unrelated reasons, and one patient's ocular details were unavailable because she passed away from severe head trauma. The following neuro-ophthalmologic or ocular manifestations were identified in the remaining 6 patients: chemosis/conjunctival injection (n = 6), cranial nerve (CN) VI palsy (n = 6), CN III palsy (n = 2), proptosis (n = 4), ocular/orbital pain (n = 3), audible orbital bruit (n = 2), ocular hypertension (n = 1), and blurred vision (n = 1). Of those patients with symptomatic CCFs, all underwent treatment except for one that spontaneously resolved. None of the patients suffered a stroke or cerebral hemorrhage. The 3 patients with incidentally discovered CCFs were asymptomatic and did not require treatment. CONCLUSIONS: This is the first population-based study to show a low incidence rate of CCFs, supporting the notion that it is an uncommon condition. Neuro-ophthalmic manifestations are common, especially chemosis/conjunctival injection and CN VI palsy. Up to a third of patients with CCF can be asymptomatic and may be found incidentally on neuroimaging during the evaluation for unrelated symptoms.

Vascular Risk Factors in Isolated Microvascular Ischemic Third Nerve Palsy: A Population-Based Study.

BACKGROUND: Although presumed microvascular third nerve palsies (TNP) have been associated with vascular risk factors and/or stroke, these associations have not been explored in a population-based cohort. The purpose of this population-based case-control study was to determine whether these factors are associated with TNPs that had been classified as isolated microvascular ischemic events and determine future risk of mortality. METHODS: Participants were subjects >18 years old with new onset of isolated TNP attributed to presumed microvascular ischemia (n = 55) while residing in Olmsted County, Minnesota, from January 1, 1978 to December 31, 2014. Control subjects (n = 55) were randomly selected from the same population and matched for gender, age, and length of medical follow-up. We identified all cases of new-onset isolated presumed microvascular ischemic TNP using the Rochester Epidemiology Project, a record-linkage system of medical records for all patient-physician encounters in Olmsted County, Minnesota. All medical records of cases and controls were reviewed for potential risk factors, including diabetes mellitus, diabetic retinopathy, hypertension, hyperlipidemia, smoking, and symptomatic ischemic stroke. Multivariable and univariate logistic regression analyses were used to compare the prevalence of potential risk factors between microvascular ischemic cases and controls according to the number of subjects, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Kaplan-Meier curves were used to compare mortality between cases and controls. RESULTS: The annual incidence of microvascular ischemic TNP was 1.7 per 100,000. Univariate analysis demonstrated that hypertension ( P < 0.001; OR, 4.80; 95% CI, 2.11-11.58), diabetes mellitus ( P < 0.001; OR, 6.55; 95% CI, 2.72-17.32), diabetic retinopathy ( P = 0.014; OR, 13.50; 95% CI, 2.48-251.55), coronary artery disease ( P = 0.047; OR, 2.27; 95% CI, 1.02-5.18), and symptomatic ischemic stroke ( P = 0.039; OR, 3.56; 95% CI, 1.07-11.85) all occurred more frequently in patients with microvascular ischemic TNP than controls. In multivariate analysis, only hypertension (OR of 4.14, 95% CI, 1.61-10.65, P < 0.001) and diabetes (OR of 4.12, 95% CI, 1.43-11.92, P = 0.003) remained independently statistically significant. There was numerically higher mortality in microvascular cases than in controls, but it did not reach statistical significance. CONCLUSIONS: There are multiple cardiovascular diseases that are associated with isolated microvascular ischemic TNP, including hypertension, coronary artery disease, diabetes mellitus, diabetic retinopathy, and symptomatic ischemic stroke. Given that the main drivers of this association seem to be diabetes and hypertension, patients with microvascular ischemic TNP should be evaluated for these conditions.

Interprofessional Electronic Consultations for the Diagnosis and Management of Neuro-Ophthalmic Conditions.

BACKGROUND: Interprofessional electronic consultation (eConsult) is a telemedicine modality in which consulting providers review outside records and provide recommendations without in-person consultation. The purpose of this study was to describe the utilization of eConsults in the management of neuro-ophthalmic conditions. METHODS: Retrospective cohort study of all patients who received an eConsult for a neuro-ophthalmic condition at a single quaternary referral center from 2018 to 2020. Main outcome measures included proportion of eConsults in which sufficient data were provided to the neuro-ophthalmologist to generate a definitive management decision, proportion of patients for whom an in-person neuro-ophthalmology evaluation was recommended, and the eConsult's impact on patient care. RESULTS: Eighty eConsults were conducted on 78 patients during the 3-year study period. Forty-eight (60.0%) subjects were female, mean age was 54 years, and 65 (81.3%) were White. The median time from eConsult request to completion was 4 days (range: 0-34 days). The most frequent eConsult questions were vision/visual field disturbances in 28 (35.0%) cases, optic neuropathies in 22 (27.5%), and optic disc edema in 17 (21.3%). At the time of eConsult, sufficient prior information was provided in 35 (43.8%) cases for the neuro-ophthalmologist to provide a definitive management decision. In 45 (56.3%) eConsults, further diagnostic testing was recommended. In-person neuro-ophthalmology consultation was recommended in 24 (30.0%) cases. Sixty-one (76.3%) eConsults provided diagnostic and/or treatment direction, and 12 (15.0%) provided reassurance. CONCLUSION: eConsults increase access to timely neuro-ophthalmic care and provide diagnostic and treatment direction to non-neuro-ophthalmology providers when sufficient information is provided at the time of eConsult.

Bilateral Simultaneous Nonarteritic Anterior Ischemic Optic Neuropathy: Demographics, Risk Factors, and Visual Outcomes.

BACKGROUND: Although nonarteritic anterior ischemic optic neuropathy is a well-known cause of vision loss, it typically presents unilaterally. Simultaneous, bilateral nonarteritic anterior ischemic optic neuropathy (sNAION) is rare and poorly studied in comparison. This study seeks to characterize the clinical features and risk factors of patients with sNAION compared with unilateral NAION (uNAION). METHODS: In this retrospective case-control study, we reviewed 76 eyes (38 patients) with sNAION and 38 eyes (38 patients) with uNAION (controls) from 4 academic institutions examined between 2009 and 2020. Demographic information, medical history, medication use, symptom course, paraclinical evaluation, and visual outcomes were collected for all patients. RESULTS: No significant differences were observed in demographics, comorbidities and their treatments, and medication usage between sNAION and uNAION patients. sNAION patients were more likely to undergo an investigative work-up with erythrocyte sedimentation rate measurement ( P = 0.0061), temporal artery biopsy ( P = 0.013), lumbar puncture ( P = 0.013), and MRI ( P < 0.0001). There were no significant differences between the 2 groups for visual acuity, mean visual field deviation, peripapillary retinal nerve fiber layer thickness, or ganglion cell-inner plexiform layer thickness at presentation, nor at final visit for those with ≥3 months of follow-up. The sNAION eyes with ≥3 months of follow-up had a smaller cup-to-disc ratio (CDR) at final visit ( P = 0.033). Ten patients presented with incipient NAION, of which 9 suffered vision loss by final visit. CONCLUSION: Aside from CDR differences, the risk factor profile and visual outcomes of sNAION patients seem similar to those of uNAION patients, suggesting similar pathophysiology.

Fluorescein Angiography Findings in Susac Syndrome: A Multicenter Retrospective Case Series.

BACKGROUND: Susac syndrome is a vasculopathy, resulting in the classic triad of branch retinal artery occlusion (BRAO), inner ear ischemia, and brain ischemia. In this retrospective chart review, we characterize fluorescein angiography (FA) findings and other ancillary studies in Susac syndrome, including the appearance of persistent disease activity and the occurrence of new subclinical disease on FA. METHODS: This multicenter, retrospective case series was institutional review board-approved and included patients with the complete triad of Susac syndrome evaluated with FA, contrasted MRI of the brain, and audiometry from 2010 to 2020. The medical records were reviewed for these ancillary tests, along with demographics, symptoms, visual acuity, visual field defects, and findings on fundoscopy. Clinical relapse was defined as any objective evidence of disease activity during the follow-up period after initial induction of clinical quiescence. The main outcome measure was the sensitivity of ancillary testing, including FA, MRI, and audiometry, to detect relapse. RESULTS: Twenty of the 31 (64%) patients had the complete triad of brain, retinal, and vestibulocochlear involvement from Susac syndrome and were included. Median age at diagnosis was 43.5 years (range 21-63), and 14 (70%) were women. Hearing loss occurred in 20 (100%), encephalopathy in 13 (65%), vertigo in 15 (75%), and headaches in 19 (95%) throughout the course of follow-up. Median visual acuity at both onset and final visit was 20/20 in both eyes. Seventeen (85%) had BRAO at baseline, and 10 (50%) experienced subsequent BRAO during follow-up. FA revealed nonspecific leakage from previous arteriolar damage in 20 (100%), including in patients who were otherwise in remission. Of the 11 episodes of disease activity in which all testing modalities were performed, visual field testing/fundoscopy was abnormal in 4 (36.4%), MRI brain in 2 (18.2%), audiogram in 8 (72.7%), and FA in 9 (81.8%). CONCLUSIONS: New leakage on FA is the most sensitive marker of active disease. Persistent leakage represents previous damage, whereas new areas of leakage suggest ongoing disease activity that requires consideration of modifying immunosuppressive therapy.

Ectopic orbital brain tissue: a case report with radiographic and clinical review.

Orbital heterotopic brain tissue is a rare entity with heterogenous clinical features requiring a multi-faceted diagnostic approach. The authors present a case of ectopic orbital brain tissue in an infant with a comprehensive literature review to highlight the radiographic findings of these lesions. Imaging findings are variable but describe well-circumscribed homogenous lesions with variable enhancement, without communication intracranially. The combination of computed tomography and magnetic resonance imaging can identify associated bony abnormalities, lesion-specific features, and effects on surrounding structures, which in combination with the clinical exam can be a valuable diagnostic and surveillance tool. Although ectopic orbital brain tumors are benign with excellent outcomes following complete resection, conservative management with observation and serial imaging may be an alternative method of management in patients with mild, non-vision threatening, non-distorting tumors.

Stroke Risk before and after Central Retinal Artery Occlusion: A Population-based Analysis.

PURPOSE: To determine the risk of stroke, transient ischemic attack (TIA), and transient monocular vision loss (TMVL) before and after a central retinal artery occlusion (CRAO). DESIGN: Population-based, retrospective case series. PARTICIPANTS: Patients diagnosed with a CRAO in Olmsted County, Minnesota, from 1976 to 2016. METHODS: Patients living in Olmsted County with a diagnosis code of CRAO from 1976 to 2016 were reviewed. New CRAOs were confirmed, and stroke, TIA, and TMVL events in the 15 days before and after CRAO were recorded. MAIN OUTCOME MEASURES: Incidence of stroke, TIA, and TMVL events in the 15 days before and after CRAO. RESULTS: Eighty-nine patients with a CRAO were identified, providing an annual incidence of 2.58/100 000 (95% confidence interval [CI], 2.04-3.11). Median age at the time of CRAO was 76 years (range, 46-100 years); 56.2% were male, and 89.9% of the cohort was White. In the 15 days before and after CRAO, there were 2 ischemic strokes (2.2%), 1 hemorrhagic stroke (1.1%), 2 TIAs (2.2%), and 9 TMVL events (10.1%). Starting in 1999, 15 of 45 patients underwent magnetic resonance imaging within 2 months of CRAO. One patient (6.7%) had evidence of asymptomatic diffusion restriction, and 9 patients (60%) had a remote infarct. CONCLUSIONS: This population-based study demonstrated that the risk of symptomatic ischemic stroke is 2.2% in the 15 days before and after a CRAO, which is slightly lower than most studies from tertiary centers. These data should be considered as practice recommendations are developed regarding the urgency of neurovascular workup in patients with acute CRAO.

Optic chiasm involvement in AQP-4 antibody-positive NMO and MOG antibody-associated disorder.

BACKGROUND: Optic neuritis (ON) is often the presenting symptom in inflammatory central nervous system demyelinating disorders. OBJECTIVE: To compare the frequency and pattern of optic chiasm involvement in patients with aquaporin-4-immunoglobulin G (AQP4-IgG)-associated ON to patients with myelin oligodendrocyte glycoprotein-immunoglobulin G (MOG-IgG)-associated ON. METHODS: Retrospective review of all patients evaluated at Mayo Clinic, Stanford University and Ramathibodi Hospital who were found to have: (1) ON, (2) either MOG-IgG or AQP4-IgG by cell-based assay, and (3) magnetic resonance imaging (MRI) at the time of ON. MRI was reviewed for contrast enhancement of the optic chiasm and the pattern of involvement. RESULTS: One hundred and fifty-four patients (74 AQP4-IgG and 80 MOG-IgG) were included. Among patients with AQP4-IgG-ON, 20% had chiasmal involvement, compared with 16% of patients with MOG-IgG-ON (p = 0.66). In patients with chiasmal involvement, longitudinally extensive optic nerve enhancement (from orbit extending to chiasm) was identified in 54% of MOG-IgG-ON patients, compared with 7% of AQP4-IgG-ON patients (p = 0.01). CONCLUSION: Chiasmal involvement of MOG-IgG-ON and AQP4-IgG-ON occur at more similar frequencies than previously reported. Furthermore, MOG-IgG-ON chiasmal involvement is more likely to be part of a longitudinally extensive optic nerve lesion.

Features of Idiopathic Intracranial Hypertension on MRI With MR Elastography: Prospective Comparison With Control Individuals and Assessment of Postintervention Changes.

BACKGROUND. Understanding of dynamic changes of MRI findings in response to intracranial pressure (ICP) changes in idiopathic intracranial hypertension (IIH) is limited. Brain stiffness, as assessed by MR elastography (MRE), may reflect changes in ICP. OBJECTIVE. The purpose of this study was to compare pituitary height, ventricular size, and brain stiffness between patients with IIH and control individuals and to evaluate for changes in these findings in patients with IIH after interventions to reduce ICP. METHODS. This prospective study included 30 patients (28 women, two men; median age, 29.9 years) with IIH and papilledema and 21 control individuals (21 women, 0 men; median age, 29.1 years), recruited from January 2017 to July 2019. All participants underwent 3-T brain MRI with MRE; patients with IIH underwent additional MRI examinations with MRE after acute intervention (lumbar puncture with normal closing pressure; n = 11) and/or chronic intervention (medical management or venous sinus stenting with resolution or substantial reduction in papilledema; n = 12). Pituitary height was measured on sagittal MP-RAGE images. Ventricular volumes were estimated using unified segmentation, and postintervention changes were assessed by tensor-based morphometry. Stiffness pattern score and regional stiffness values were estimated from MRE. RESULTS. In patients with IIH, median pituitary height was smaller than in control individuals (3.1 vs 4.9 mm, p < .001) and was increased after chronic (4.0 mm, p = .05), but not acute (2.3 mm, p = .50), intervention. Ventricular volume was not different between patients with IIH and control individuals (p = .33) and did not change after acute (p = .83) or chronic (p = .97) intervention. In patients with IIH, median stiffness pattern score was greater than in control individuals (0.25 vs 0.15, p < .001) and decreased after chronic (0.23, p = .11) but not acute (0.25, p = .49) intervention. Median occipital lobe stiffness was 3.08 kPa in patients with IIH versus 2.94 kPa in control individuals (p = .07) and did not change after acute (3.24 kPa, p = .73) or chronic (3.10 kPa, p = .83) intervention. CONCLUSION. IIH is associated with a small pituitary and increased brain stiffness pattern score; both findings may respond to chronic interventions to lower ICP. CLINICAL IMPACT. The "partially empty sella" sign and brain stiffness pattern score may serve as dynamic markers of ICP in IIH.

Post-cataract surgery optic neuropathy: a chronological narrative review of the literature and speculation on pathogenesis.

PURPOSE OF REVIEW: To appraise the literature on the incidence of an acute anterior optic neuropathy resembling spontaneous nonarteritic anterior ischemic optic neuropathy (NAION) following uncomplicated cataract surgery and to explore the proposed pathogenesis of both immediate and delayed onset post-cataract surgery optic neuropathy (PCSON). RECENT FINDINGS: A number of case reports, case series, and retrospective case-controlled, big data, and population-based studies have identified an apparent association between cataract surgery and the occurrence of an acute anterior optic neuropathy that can either be immediate or delayed in onset. However, a recent study found no link between modern day cataract surgery and an increased risk of an acute anterior optic neuropathy. SUMMARY: Immediate PCSON appears to be related to negative perfusion pressure at the level of the optic disc due to increased intraocular pressure. The pathogenesis of delayed PCSON is unknown but probably multifactorial. Patients who have experienced spontaneous NAION or PCSON in one eye may be at risk of PCSON in the fellow eye.

Optic Disc Drusen in Patients With Ocular Hypertension: A Case Series and Review of the Literature.

BACKGROUND: The identification of glaucomatous optic neuropathy in the setting of optic disc drusen (ODD) is a challenge, and the decision of whether to offer treatment in the form of intraocular pressure (IOP) reduction is controversial. Here, we present a series of patients with coexisting ocular hypertension and ODD to evaluate clinical features, treatment options, and progression of optic neuropathy. In addition, a review of the literature on ODD with elevated IOP is provided. METHODS: Six patients with ODD and a history of ocular hypertension are presented. Components of the examination and imaging modalities used to establish the diagnosis of ODD were recorded and a description of ocular hypertension history, glaucoma testing, and the potential treatment of IOP were also provided. RESULTS: In this series, 4 of 6 patients with concurrent ocular hypertension and ODD showed progression of optic neuropathy as assessed by visual field or retinal nerve fiber layer thickness. Of the 2 patients who did not show evidence of progression, 1 was treated with IOP-lowering medications and 1 was observed off treatment. Of the 4 patients who showed evidence of progression, all 4 were initially treated with IOP-lowering medications and 2 ultimately went on to have trabeculectomy surgery. In the patients with progressive optic neuropathy, lowering the IOP seemed to halt the progression suggesting there was a pressure-sensitive component. CONCLUSIONS: Distinguishing changes to the optic nerve, particularly the structural changes at the lamina cribrosa of true glaucomatous optic neuropathy in the setting of ODD, is a challenge. Careful consideration of risk factors including age, presenting features, progression indicators, and management goals is to be accounted for in the decision to offer treatment. We see the presence ODD in the patients with ocular hypertension as an additional risk for progressive changes to the nerve fiber layer and visual field that needs to be considered when determining whether to initiate therapy. Our data suggest that treatment of IOP in the patients with ocular hypertension with ODD and evidence of progression reduces the risk of further progression. Further work is needed to determine whether progression of optic neuropathy in the setting of coexisting ODD and ocular hypertension is related mechanistically to predominantly an ODD-type process, a glaucomatous process, or a combination thereof.

Population-Based Evaluation of Indirect Signs of Increased Intracranial Pressure.

BACKGROUND: The Mayo Clinic Study of Aging (MCSA) is a unique prospective study that systematically evaluates the normal aging population and includes many participants undergoing both MRI and lumbar puncture (LP). Using MCSA date, we aimed to determine the prevalence of indirect signs of raised intracranial pressure (ICP) on MRI and whether these correlate with LP opening pressure (OP). This is a large-scale study that evaluates how often indirect signs of increased ICP occur in a normal population. METHODS: MCSA participants who had an MRI within 3 months of an LP with recorded OP were included in the study. MRIs were reviewed for indirect signs of raised ICP, including pituitary to sella (P/S) ratio, cerebellar tonsillar ectopia, and optic nerve sheath diameter (ONSD). These signs were evaluated for correlations with OP and influences from body mass index (BMI) and obstructive sleep apnea (OSA). RESULTS: Five hundred ninety-seven MCSA patients were identified who underwent both LP and MRI. Two hundred sixty (43.6%) were women. The median age was 70.7 years (range 32.6-92.7). Median OP was 152 mm H2O (range 60-314 mm H2O), with 91 (15.2%) participants having an OP ≥ 200 mm H2O. Empty or partially empty sella was seen in 81 (12.8%) of the cohort. The P/S ratio decreased with increasing OP (r = -0.3, P < 0.001). There was a weak correlation between OP and average ONSD (r = 0.184, P = 0.01), which was no longer significant when accounting for age, gender, and BMI (partial r2 = 0.014, P = 0.097). There was no correlation between OP and cerebellar tonsillar ectopia. OSA was associated with increased ONSD (P = 0.004), but this did not remain statistically significant after accounting for age, gender, and BMI (P = 0.085). CONCLUSION: Smaller pituitary gland size correlated with increasing OP. This suggests that ICP is a continuum with some normal individuals demonstrating asymptomatic radiologic signs of raised ICP.

Comparison of 1.5 Tesla and 3.0 Tesla Magnetic Resonance Imaging in the Evaluation of Acute Demyelinating Optic Neuritis.

BACKGROUND: Optic neuritis (ON) is the most common optic neuropathy in young adults. MRI is reported to have a high sensitivity for ON. Higher signal strengths of MRI may enhance resolution and lead to better detection of ON. We sought to compare the sensitivity of 3.0 Tesla (T) MRI to that of 1.5 T MRI in detecting acute demyelinating ON. METHODS: A retrospective chart review was performed on patients with a clinical diagnosis of optic neuritis at Mayo Clinic Health System from January 2010 to April 2020. Among 1,850 patients identified, 126 patients met the eligibility criteria. Exclusion criteria comprised questionable or alternative diagnosis, diagnosis of ON before the study period, eye examinations performed elsewhere, or absence of fat-saturated head and orbits MRIs performed locally within 30 days of symptom onset. Gadolinium contrast enhancement, T2 hyperintensity, and the radiologic diagnosis of ON were recorded by a neuro-radiologist who was masked to the clinical history and the magnet strength of the MRI. RESULTS: Fifty-three patients (42.1%) had 3.0 T MRI, and 73 patients (57.9%) had 1.5 T MRI. Overall, 88.9% (112/126) of patients were determined to have a positive MRI for ON. The radiographic sensitivity for ON was higher in the 3.0 T group compared with the 1.5 T group (98.1% vs 82.2%, respectively [ P = 0.004]). The frequency of gadolinium enhancement was found to be greater in the 3 T group compared with the 1.5 T group (98.1% vs 76.7%, respectively [ P < 0.001]). T2 hyperintensity was also more often seen in the 3.0 T group compared with the 1.5 T group (88.7% vs 68.5%, respectively [ P = 0.01]). CONCLUSIONS: 3.0 T MRI is more sensitive than 1.5 T MRI in detecting ON. This finding suggests that 3.0 T MRI is a preferred imaging modality for the confirmation of ON.

Characterization and Utility of Remote Interpretation of Visual Field Diagnostic Testing in an Academic Center.

BACKGROUND: The use of remote interpretation of data has risen in neuro-ophthalmology to increase efficiency and maintain social distancing due to the coronavirus disease-19 pandemic. The purpose of this study is to characterize the use and efficiency of remote interpretation of visual fields (VFs) in an academic center and to determine how often the VF interpretation was consistent with the patient's clinical history and imaging at the time of the consult. METHODS: This is a retrospective study at a single academic center that enrolled all patients receiving a remote interpretation of VF from January 1, 2012, through December 31, 2012. Data were collected regarding the referring department, indication for the VF, interpretation of the VF and comparison with any prior VFs, any associated interventions with the VF, and available follow-up VFs. The main outcome measures included 1) characterizing the use of remote VF interpretations and 2) how many remote VF interpretation results were consistent with the referring diagnosis based on the patient's clinical history and imaging. RESULTS: One hundred eighty patients received remote interpretation of VFs. The most frequent referring departments were endocrinology (79; 44%), neurology (51; 28%), and neurosurgery (43; 24%). The VF indications included parasellar lesion (107; 59%), seizure disorder (26; 14%), meningioma (19; 11%), vascular lesion (11; 6%), and others (17; 9%). There were 78 patients (43%) that had an intervention before the VF, whereas 49 (27%) were preoperative VFs. Eighty-seven (48%) of the VFs were interpreted as abnormal. Of all the 180 remote interpretation of VFs, 156 (87%) had VF interpretations that were consistent with the clinical question posed by the referring provider based on clinical history and imaging. Among the other 24 remote VF interpretations (13% of total remote VF interpretations), there was no clear interpretation because of either additional unexpected VF defects (n = 5, 21%), VF defect mismatch (n = 6, 25%), or unreliable VFs (n = 13, 54%). The median wait time for patients receiving remote VF interpretations was 1 day. CONCLUSIONS: Remote interpretation of VFs was most often requested by endocrinology, neurology, and neurosurgery and could be performed very quickly. The most common indications were parasellar lesions, and just less than half of patients receiving remote VF interpretations had a prior intervention. A majority of remote VF interpretations were able to answer the clinical question, given the patient's clinical history and imaging. Remote interpretation of VFs may thus offer referring departments a more efficient method of obtaining VF interpretations than in-office neuro-ophthalmology examinations.

The 'Fault' Lies in the Choroid: Peripapillary Intrachoroidal Cavitation Presenting with Progressive Vision Loss.

A 55-year-old male was referred to the Neuro-ophthalmology clinic due to gradual onset, progressive vision loss. On fundus examination a subtle yellow-orange peripapillary lesion was detected in the left eye. Optical coherence tomography with radial scanning illustrated retinal nerve fibre layer thinning as well as an area of intrachoroidal cavitation that corresponded to the lesion. Visual field testing showed a left inferior arcuate defect. Magnetic resonance imaging of the brain and orbit, and laboratory testing was unremarkable. Clinical examination, imaging, and testing were consistent with peripapillary intrachoroidal cavitation (PICC). Follow-up with serial visual field testing showed mild progression of the field defect. While PICC is not well understood in the literature, studies have reported associated risk factors including pathological myopia, older age, increased ocular axial length, chorioretinal atrophy, and vascular abnormalities. Importantly, glaucoma-like visual field defects as well as structural changes have been noticed in a high proportion of patients with PICC. While these alterations are evident, the pathogenic relationship between them is yet to be uncovered. Treatment with anti-glaucoma medications has been suggested, however, the evidence remains scarce for its true benefits. Care providers must be aware of the presentation of a yellow-orange peripapillary lesion with an associated visual field defect to accurately diagnose and manage this condition.

Population-based Rate and Patterns of Diplopia in Giant Cell Arteritis.

Giant cell arteritis (GCA) is the most common vasculitis in older adults with permanent vision loss as a feared complication. Diplopia has been reported in a small percentage of patients with visual manifestations. The goal of this study was to determine the population-based rates and patterns of binocular diplopia from GCA. The Rochester Epidemiology Project (REP), a medical records linkage system was used to identify all residents of Olmsted County, Minnesota, USA, diagnosed with GCA between January 1, 1950 and December 31, 2019. Medical records were then reviewed to identify patients with binocular diplopia from GCA. There were 301 incident cases of GCA from 1950 to 2019. Fourteen (5%) patients presented with binocular diplopia. Of these 14 patients, nine (3%) had constant diplopia and five (2%) had transient diplopia. Among patients with constant diplopia, cranial nerve VI involvement was suspected in four (44%) cases. Systemic symptoms and inflammatory markers were similar in patients with and without diplopia. There was no difference in the rate of anterior ischaemic optic neuropathy between the two groups (7% vs. 7%, p = 1.00). In conclusion, this population-based study showed that binocular diplopia was present in 5% of patients with GCA, which could either be transient or constant. GCA patients with diplopia had similar systemic manifestations and risk of vision loss as GCA patients without diplopia.