Neuro-Ophthalmic Literature Review

Neuro-Ophthalmic Literature Review David A. Bellows, Noel C.Y. Chan, John J. Chen , Hui-Chen Cheng, Peter W. MacIntosh, Jenny A. Nij Bijvank, Michael S. Vaphiades, Konrad P. Weber, and Sui H. Wong Clinical characteristics of idiopathic intracranial hypertension in patients over 50 years of age: A multicenter clinical cohort study Downie, PA, Chen JJ, Bhatti MT, Melson AT, Van Stavern GP, McClelland CM, Lindgre BR, Sharieff JA, Lee MS. Clinical Characteristics of Idiopathic Intracranial Hypertension in Patients Over 50 Years of Age: A multicenter clinical cohort study. Am Journal Ophthalmol. 2021;224: 96–101. This multicenter study analysed the clinical characteristics of 65 patients over the age of 50 years (median age 54 years) with idiopathic intracranial hypertension (IIH) and compared these to a control group of patients with IIH who were under the age of 50 years (median age 30 years). There were several significant characteristics that distinguish the two groups including sex distribution, symptoms, cerebrospinal fluid pressure, comorbidities, and outcomes. The older age group showed a lower preponderance of females (78.5% vs. 92.3%). In regards to symptoms the older group of patients had fewer headaches (50.8% vs. 80%). However, the incidence of other symptoms such as pulse-synchronous tinnitus, vision changes, transient visual obscurations, and diplopia were similar in both cohorts. The older age group had a higher rate of comorbidities (hypertension, diabetes, and thyroid disease) but there was no difference between the groups in the rates of sleep apnoea, anaemia, or polycystic ovarian syndrome. Older patients were less likely to be on cycline-type antibiotics (0% vs. 10.8%). Interestingly, an older age was not found to be associated with a worse outcome as determined by mean deviation on perimetry or need for surgical intervention. David A. Bellows Titre matters when interpreting MOG-IgG! Sechi E, Buciuc M, Pittock SJ, Chen JJ, Fryer JP, Jenkins SM, Budhram A, Weinshenker BG, LopezChiriboga AS, Tillema J-M, McKeon A, Mills JR, Tobin WO, Flanagan EP. Positive Predictive Value of Myelin Oligodendrocyte Glycoprotein Autoantibody Testing. JAMA Neurol. 2021;78(6):741–746. doi:10.1001/jamaneurol.2021.0912 In the recent decade, neuroinflammatory or demyelinating diseases such as neuromyelitis optica (NMO) and myelin oligodendrocyte glycoprotein (MOG)IgG1 associated disorder (MOGAD) had gained more attention from neurologists and neuroophthalmologists with an increased popularity and acceptance in early testing of related antibodies. The change in ordering practice is understandable given the distinct nature and different managements required for these disorders. However, false-positive results can occur and it might be about time to evaluate the positive predictive value (PPV) of these tests in the real world. In this study, patients who were consecutively tested for MOG-IgG1 by live cell-based flow cytometry during their diagnostic workup in the Mayo Clinic were included and the medical records were reviewed by 2 investigators blinded to MOG-IgG1 serostatus for determining pre-test probability of MOGAD. Within the 2-year study period, 1260 patients were included of whom 92 (7.3%) were positive for MOG-IgG1. These positive cases were then independently designated by 2 neurologists as true-positive or false-positive at last follow up based on current international recommendations on diagnosis. Twenty-six results (28%) were eventually designated as false positive with alternative diagnosis including multiple sclerosis (n = 11), infarction (n = 3), B12 deficiency (n = 2), biopsy-proven neoplasia (n = 2) and others (n = 8). The overall PPV CONTACT John J. Chen Chen.john@mayo.edu Department of Ophthalmology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA NEURO-OPHTHALMOLOGY 2021, VOL. 45, NO. 4, 283–291 https://doi.org/10.1080/01658107.2021.1947658 © 2021 Taylor & Francis Group, LLC was 72% but the PPV was found to be titre dependent (PPVs: 1:1000, 100%; 1:100, 82%; 1:20–40, 51%). The PPV was higher for children (94%) and for patients with higher pre-test probability (85%). The authors concluded that MOG-IgG1 is a highly specific biomarker for MOGAD in clinical practice with a test specificity of 97.8%. However, it has a low PPV of 72% when using a titre cut-off of 1:20. Clinicians should take caution when interpreting low-titre positivity in patients with atypical phenotypes. With the test specificity similar to prior studies in experimental populations, PPV in clinical practice was noted to be lower which can be due to different disease prevalence as well as ordering practices. Given the increased PPV with higher pre-test probability, indiscriminate MOG-IgG1 testing is therefore not recommended. In particular, multiple sclerosis was noted to be overrepresented among patients with false-positive results. This should dissuade clinicians from uniform ordering of MOG-IgG1 testing in patients with typical MS. Alternative diagnosis should also be sought in patients with red flags that argue against MOGAD despite a positive serology. Noel C. Y. Chan Neuro-ophthalmologists can prevent patient harm Stunkel L, Sharma RA, Mackay DD, Wilson B, Van Stavern GP, Newman NJ, Biousse V. Patient Harm due to Diagnostic Error of Neuro-Ophthalmologic Conditions. Ophthalmology. 2021;S0161-6430(21)00193–7. doi:10.1016/j.ophtha.2021.03.008. Online ah-ead of print.