The internal limiting membrane (ILM), composed of collagen fibers, glycosaminoglycans, laminin and fibronectin, is the basement membrane of the retinal Müller glia cells and serves as an interface between the vitreous and retina. The ILM is the structural interface between the vitreous and retina. ILM removal ensures separation of the posterior hyaloid from the macular surface, which can relieve macular traction and prevent postoperative epiretinal membrane formation. Thus, vitrectomy with ILM peeling has become an increasingly utilized and vital component in surgical intervention for various vitreoretinal disorders. However, many recent studies showed that ILM peeling is a procedure that can cause immediate traumatic effects and progressive modification on the underlying inner retinal layers.There were some surgical strategy (fovea-sparing ILM peeling or inverted internal limiting membrane flap technique, or Abrasion Technique). But some controversies exist, such as when ILM peeling is necessary, which adjuvant to use to perform the procedure, and what is the best technique to peel the ILM. A full assessment ILM structure and function and related factors of surgery is helpful to predict the anatomical and functional prognosis.
Objective To observe the characteristics of multiple evanescent white dot syndrome (MEWDS) with modern multimodal imaging modalities. Methods This was a retrospective case study. Eleven patients (11 eyes) diagnosed with MEWDS were enrolled. There were 10 females and 1 male, mean age was 27.6 years (range 15-41 years). The period between disease onset and visiting to the hospital was between 2 to 13 days, the average time was 4.7 days. All the patients underwent examinations of best corrected visual acuity, slit-lamp biomicroscope, indirect ophthalmoscope, fundus color photography, fundus autofluorescence (FAF), fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA) and spectral domain optical coherence tomography (SD-OCT). The mean follow up duration was 3.2 months. The imaging characteristics were compared. Results Fundus color photography showed foveal orange-red granularity in all eyes. FAF showed strong autofluorescence with a vague boundary. FFA showed a variable number of highly fluorescent fine needle-like dots arranged in a ring in the early stage, and fluorescence remained in the late stage. ICGA showed advanced lesions of vague boundary merged into a large plaque of deep retinal hypofluorescence. SD-OCT showed the hyperreflectant material deposit over the retinal pigment epithelium and extending anteriorly through the interdigitation zone, ellipsoid layer, and toward the external limiting membrane. At the site of extrafoveal lesions, SD-OCT revealed the presence of discontinuities or disruptions centered on the ellipsoid zone to include the interdigitation. Conclusions In MEWDS patients, fundus photography showed foveal orange-red granularity; FFA showed early fluorescent dots distributed in a ring pattern; ICGA showed hypofluorescent lesions in the later stage; SD-OCT showed disruption of the interdigitation zone and ellipsoid zone and accumulations of hyperreflective material that was of variable size and shape; FAF showed strong autofluoresce areas that correlated to spots observed with FFA and ICGA.