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, and Xiaojun Zhang The many faces of ocular syphilis: Case-based update of recognition, diagnosis, and treatment Schulz DC, Orr SMA, Johnstone R, Devlin MK, Sheidow TG, Bursztyn LLCD. The many faces of ocular syphilis: Case-based update of recognition, diagnosis, and treatment. Can J Ophthalmol. 2021;56(5):283–293. doi: 10.1016/j.jcjo.2021.01.006. Syphilis has become increasingly prevalent with over 5 million cases occurring, worldwide, in adolescents and young adults. Although occurring primarily in men who have sex with men or those with HIV, the demographic is changing, and the disease is infecting more women and heterosexual men. These patients can present to the ophthalmologist or neuro-ophthalmologist, and it is important that we understand how to make the diagnosis and treat in order to prevent serious sequelae. The authors reviewed the personal records of eight practitioners including specialists in neuroophthalmology, uveitis, retina, and infectious diseases. They captured 26 cases of ocular syphilis and found that four patients were co-infected with HIV and one with chlamydia. Only 12 patients disclosed their risk factors for acquiring the infection and three of these patients were only willing to do so after the diagnosis had been made. There is much confusion regarding the serological testing for syphilis and the authors review the testing algorithm, which includes both Treponemal and non-Treponemal assays, that is used in making the diagnosis, confirming active disease, and monitoring the response to treatment. The authors review the use of both penicillin and ceftriaxone for the treatment of syphilis and emphasise that corticosteroids can be safely used, prior to the diagnosis, in cases where prompt treatment is necessary. David A. Bellows OCTA: NAION vs NTG Kim JA, Lee EJ, Kim TW, Yang HK, Hwang JM. Comparison of optic nerve head microvasculature between normal-tension glaucoma and nonarteritic anterior ischaemic optic neuropathy. Invest Ophthalmol Vis Sci. 2021;62(10):15. doi: 10.1167/ iovs.62.10.15 This cross-sectional study compared the microvasculature of the optic nerve head (ONH) and the peripapillary region between normal tension glaucoma (NTG) and non-arteritic anterior ischaemic optic neuropathy (NAION). Most of the time, the characteristics of the acute phase and disc morphology of NAION are diagnostic for the condition. However, in the non-acute phase, NAION can sometimes present with enlargement of the optic cup with relative preservation of visual acuity or colour vision. Together with retinal nerve fibre layer (RNFL) thinning and visual field defects of similar patterns as glaucoma, it can sometimes pose a diagnostic challenge to ophthalmologists. Interestingly, impaired perfusion of the ONH is considered a potential pathogenic factor in both. NAION is thought to result from retrolaminar circulatory insufficiency in territory supplied by the short posterior ciliary arteries (SPCA), while studies have shown NTG to be associated with decreased ONH perfusion. Using optical coherence tomography angiography, vessel density (VD) was compared among treatment-naive NTG, NAION, and age-matched controls in each layer: prelaminar tissue (PLT); lamina cribrosa (LC); and peripapillary retina (PR). The authors found that VDs in PLT and LC were lower in NTG eyes than in both NAION and healthy eyes, and did not differ between NAION and healthy eyes. VD in the PR did not differ between NTG and NAION eyes, while they were both lower in the affected than the unaffected sector CONTACT John J. Chen Chen.john@mayo.edu Department of Ophthalmology, Mayo Clinic, 200 First Street, SW, Rochester, MN 55905, USA NEURO-OPHTHALMOLOGY 2022, VOL. 46, NO. 1, 68–74 https://doi.org/10.1080/01658107.2021.2009732 © 2021 Taylor & Francis Group, LLC for both conditions. Clinically, systolic blood pressure, mean arterial pressure, and mean ocular perfusion pressure were significantly higher in the NAION eyes than in both NTG and healthy eyes. The authors hypothesised that the thicker PLT in NAION than NTG was due to reactive gliosis in NAION eyes as opposed to axonal degeneration in NTG. It can also be from luxury perfusion in NAION with vascular autoregulatory response after the acute insult to increased oxygenation noted in the later stages of NAION. The decreased VD in the PR, but not in the PLT or LC, of the affected sector for both conditions indicates that the vascular system supplying these tissues is independent: the central retinal artery and the SPCA system. The similar VD-PR of RNFL-thickness matched patients of NAION and NTG also suggest that VD-PR may indicate secondary loss in areas of RNFL atrophy, rather than differences in the pathomechanisms of the two diseases. The strength of this study is that recruited NAION eyes were matched for RNFL thickness in superior and inferior quadrant as it is known that VD is positively correlated with RNFL thickness. Nevertheless, their findings likely reflect differences in ONH morphology and the pathogenesis of these two diseases of vascular aetiologies. Additional studies are, however, required to determine if VD differences in ONH tissues can be used to distinguish between the two in the future. Noel C.Y. Chan The 2021 National Eye Institute Strategic Plan Chiang MF, Tumminia SJ. The 2021 National Eye Institute Strategic Plan: eliminating vision loss and improving quality of life. Ophthalmology. 2021 Oct 25;S0161-6420(21)00729–6. doi: 10.1016/j. ophtha.2021.09.012 The National Institute of Health recently selected Dr. Michael Chiang as the new director of the National Eye Institute (NEI). One of his first tasks was to update NEI’s strategic plan, which had not been updated since 2012. As part of the strategic plan, NEI’s mission was revised for the first time since the founding of NEI in 1968, which now reads “The mission of the National Eye Institute is to eliminate vision loss and improve quality of life through vision research”. One of the main strategies is to promote collaboration across fields. NEI is currently organised by anatomic disease (retina, cornea, lens and cataract, glaucoma and optic neuropathy, strabismus, amblyopia, and visual processing, and vision rehabilitation). Rather than replacing these categories, the new strategic plan adds seven cross-cutting areas of emphasis: genetics; neuroscience; immunology; regenerative medicine; data science; quality of life; and public health and health disparities. The addition of these seven areas will foster interdisciplinary approaches and collaboration. The new strategic plan is exciting and will be the guiding principles of the NEI for at least the next decade. John J. Chen Epivascular glia can be observed by en face optical coherence tomography Grondin C, Au A, Wang D, Gunnemann F, Tran K, Hilely A, Sadda S, Sarraf D. Identification and Characterisation of Epivascular Glia Using En Face Optical Coherence Tomography. Am J Ophthalmol 2021;229:108–119. doi: 10.1016/j. ajo.2021.03.014. The authors conducted a retrospective crosssectional study to describe the clinical features of epivascular glia (EVG) by en face optical coherence tomography (OCT), which could only be observed by electron microscopy or immunostaining in the past. EVG was defined as characteristic hyperreflective internal limiting membrane plaques with dendrite-like radiations and vascular predilection on en face OCT. A total of 161 eyes with EVG and 2,315 eyes without EVG (control group) were enrolled. The prevalence of EVG was 161 out of 2,476 eyes (6.5%) and 119 out of 1,298 patients (9.2%). Patients with EVG were older than the control group (mean age 79.3 versus 55.9 years old in the EVG and control groups, respectively, P < .001). An advanced posterior vitreous detachment (PVD) stage was more common in the EVG group compared with the control group (P < .001). A contractile ERM was present in 71 out of 161 eyes (44.1%) with EVG compared with 30 out of 161 eyes (18.6%) in the control group (P < .001). The authors concluded that EVGs were highly NEURO-OPHTHALMOLOGY 69