Abstract text (incl. figure legends and references)

Question

Atypical Idiopathic Intracranial Hypertension is a term for cases that do not fit into the classical phenotype of reproductive aged females with obesity. Normal BMI at presentation is uncommon, with potentially different underlying mechanism and management, given that weight loss is currently the only disease-modifying therapy in IIH. Therefore, the prognosis for this subset of atypical IIH needs to be investigated.

Aims and methods

Through a prospectively collected cohort within the IIH Life database (2012-2021), based on baseline BMI. Evaluate visual and headache outcomes. These would include LogMAR visual acuity; Humphrey visual field perimetric mean deviation (PMD) and optical coherence tomography (OCT).

Results

Visual and headache outcomes are not significantly different by baseline BMI with comparable outcomes.

Conclusions

Patients with a normal body mass index make up a small proportion of IIH patients but appear to have similar visual and headache outcomes than more typical IIH. The metabolic phenotype may be different in these patients; however they may also be more susceptible to sequelae of IIH at lower weights.