Assessment of the uniform field electroretinogram for mouse retinal ganglion cell functional analysis.

PURPOSE: The uniform field electroretinogram (UF-ERG) has been suggested as an alternative to the pattern electroretinogram (PERG) for non-invasive assessment of retinal ganglion cell (RGC) function in primates. We evaluated the validity of the UF-ERG to assess mouse RGC activity in vivo. METHODS: Unilateral optic nerve crush (ONC) was performed on adult C57BL/6J mice. Contralateral eyes with uncrushed optic nerves and eyes from surgically naive mice served as experimental controls. Electrophysiological visual assessment was performed at 12 weeks post-ONC. Flash-mediated visual-evoked cortical potentials (VEPs) were measured to confirm the robustness of the ONC procedure. Full-field flash ERGs were used to interrogate photoreceptor and retinal bipolar cell function. RGC function was assessed with pattern ERGs. Summed onset and offset UF-ERG responses to alternating dark and light uniform field flash stimuli of different intensities and wavelengths were recorded from ONC and control eyes, and relative differences were compared to the PERG results. Following electrophysiological analysis, RGC loss was monitored by immunohistochemical staining of the RGC marker protein, RBPMS, in post-mortem retinal tissues. RESULTS: ONC dramatically impacts RGC integrity and optic nerve function, demonstrated by reduced RGC counts and near complete elimination of VEPs. ONC did not affect scotopic ERG a-wave and b-wave amplitudes, while PERG amplitudes of eyes subjected to ONC were reduced by approximately 50% compared to controls. Summation of ON and OFF UF-ERG responses did not reveal statistically significant differences between ONC and control eyes, regardless of visual stimulus. CONCLUSIONS: PERG responses are markedly impaired upon ONC, while UF-ERG responses are not significantly affected by surgical trauma to RGC axons in mice. The more closely related pattern and uniform field ERGs recorded in primates suggests species-specific differences in RGC features or subpopulations corresponding to PERG and UF-ERG response generators, limiting the utility of the UF-ERG for mouse RGC functional analysis.

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.

Neuro-ophthalmic Complications of Immune Checkpoint Inhibitors: A Systematic Review.

OBJECTIVE: Immune checkpoint inhibitors (ICIs) are novel cancer therapies that may be associated with immune-related adverse events (IRAEs) and come to the attention of neuro-ophthalmologists. This systematic review aims to synthesize the reported ICI-associated IRAEs relevant to neuro-ophthalmologists to help in the diagnosis and management of these conditions. METHODS: A systematic review of the literature indexed by MEDLINE, Embase, CENTRAL, and Web of Science databases was searched from inception to May 2020. Reporting followed the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. Primary studies on ICIs and neuro-ophthalmic complications were included. Outcomes included number of cases and incidence of neuro-ophthalmic IRAEs. RESULTS: Neuro-ophthalmic complications of ICIs occurred in 0.46% of patients undergoing ICI and may affect the afferent and efferent visual systems. Afferent complications include optic neuritis (12.8%), neuroretinitis (0.9%), and giant cell arteritis (3.7%). Efferent complications include myasthenia gravis (MG) (45.0%), thyroid-like eye disease (11.9%), orbital myositis (13.8%), general myositis with ptosis (7.3%), internuclear ophthalmoplegia (0.9%), opsoclonus-myoclonus-ataxia syndrome (0.9%), and oculomotor nerve palsy (0.9%). Pembrolizumab was the most common causative agent for neuro-ophthalmic complications (32.1%). Mortality was highest for MG (19.8%). Most patients (79.8%) experienced improvement or complete resolution of neuro-ophthalmic symptoms due to cessation of ICI and immunosuppression with systemic corticosteroids. CONCLUSION: While incidence of neuro-ophthalmic IRAEs is low, clinicians involved in the care of cancer patients must be aware of their presentation to facilitate prompt recognition and management. Collaboration between oncology and neuro-ophthalmology teams is required to effectively manage patients and reduce morbidity and mortality.