Incidence, morphology, and classification of epimacular membrane rip

To describe the incidence, associated factors, morphology, and visual characteristics of a series of patients with tears within an epimacular membrane (EMM).

Consecutive, prospective, observational case series of patients with EMM rip. Patients were evaluated with spectral domain optical coherence tomography, infrared photography, and fundus autofluorescence. Symptomatic patients were treated with pars plana vitrectomy and EMM removal. Follow-up imaging evaluation was performed at 3-month intervals.

A total of 761 patients presented with EMM. Thirty-four eyes of 34 patients (4.5%) developed EMM rip. Frequent associated features included history of cataract extraction, diabetes mellitus, and retinal tear treated with photocoagulation. Morphologic characteristics included a scrolled torn edge of internal limiting membrane/EMM. Rip patterns include horseshoe shapes and patchy confluent striae and appeared as dark lines on infrared or fundus autofluorescence imaging. The EMM rips were classified as Type 1 if the rip occurred within 500 μm of the foveola on spectral domain optical coherence tomography and Type 2 if extrafoveal. Foveal involvement was associated with worse presenting vision (P = 0.002) and visual outcome after EMM removal (P = 0.012). Previous retinal tear was associated with worse visual outcome.

The EMM rip occurs in a small but significant minority of patients with EMM. Foveal involvement leads to increased visual deficit and may indicate a worse visual outcome at presentation and after intervention. Fundus autofluorescence and infrared imaging are useful in identifying EMM rip patterns.