Flame-shaped epiretinal membranes: expanding the spectrum beyond neurofibromatosis type 2

To characterize the spectral-domain optical coherence tomography (SD-OCT) features of flame-shaped epiretinal membranes (ERMs) in patients with and without neurofibromatosis type 2 (NF2).

This retrospective study included 9 patients (13 eyes) with flame-shaped ERMs from 3 tertiary centres. Multimodal imaging and clinical data were systematically analyzed.

Six of 9 subjects with flame-shaped ERM were confirmed NF2 patients. Among the NF2 cohort of 12 eyes, SD-OCT revealed flame-shaped ERMs in 10 eyes (83%). Flame-shaped ERMs were bilateral in 4 patients (8 eyes) and unilateral in 2 patients (2 eyes). The fellow eyes of these 2 unilateral patients demonstrated combined hamartoma of the retina and retinal pigment epithelium (CHRRPE) and a retinal tuft, respectively. Isolated CHRRPE was noted in 3 eyes (25%) and a retinal tuft in 2 eyes (17%). Multiple retinal findings within the same eye occurred in 3 NF2 patients. By contrast, all 3 non-NF2 patients exhibited unilateral flame-shaped ERMs: 2 with CHRRPE and 1 isolated. OCT angiography performed in 4 patients revealed hyper-reflective foci anterior to the retinal nerve fibre layer in all 3 NF2 patients. During mean follow-up of 6.2 ± 3.4 years, findings remained stable in 78% of patients. One NF2 patient developed intraretinal cysts, while 1 non-NF2 patient underwent vitrectomy.

Flame-shaped ERMs are strongly associated with NF2, and bilateral retinal lesions were present in all NF2 patients. However, they can also occur unilaterally with or without CHRRPE in non-NF2 cases. Early recognition of flame-shaped ERMs enables timely and systematic NF2 evaluation.