Purpose
To characterize the features of hyporeflective epiretinal proliferations in vitreomacular interface disorders.
Methods
This is a retrospective review of patients with lamellar macular hole (LMH), epiretinal membrane (ERM), macular pseudohole (MPH), full-thickness macular hole (FTMH) and vitreomacular traction syndrome (VMT). Patients from September 2009 to February 2014 were identified through ICD-9 billing codes. All SDOCT images were obtained using Cirrus HD-OCT. If present, the hyporeflective proliferation was further characterized. Patients with history of intravitreal therapy or vitrectomy were excluded. OCT images were analyzed Cirrus review software as well as a novel OCT analysis software for area and volumetric analysis of pathology. Brightness of the epiretinal proliferation and each retinal layer was evaluated by Image J software.
Results
Epiretinal proliferation was found in 304 of 4144 eyes (7.3%); 178 of 305 eyes with LMH (58.4%), 31 of 204 eyes with FTMH (12.9%), 93 of 3365 eyes with ERM (2.8%), 2 of 102 eyes with MPH (2%) and 0 of 132 eyes with VMT. Of the eyes with LMH, age with the proliferation (mean; 71.7) was not significantly differenced with that without the proliferation (71.9). The visual acuity of these two groups was not significantly changed during observation period (P = 0.86, 0.33, respectively). The maximum thickness (35.1 ± 21.6 μm at initial visit, 42.1 ± 23.5 at final visit), maximum area (0.045 ± 0.046 mm2, 0.056 ± 0.052), volume (0.048 ± 0.074 mm3, 0.064 ± 0.096) were significantly increased during this observation (P < 0.01, for all). The epiretinal proliferation in LMH were encapsulated by ERM (group A) in 60 of 178 (34%) eyes as shown in figure 1, and 118 (66%) eyes did not have encapsulated epiretinal proliferations (group B) also shown in figure 2. The maximum thickness, maximum area and volume were all significantly larger in the group B than group A (P < 0.01, for all). The brightness of the epiretinal proliferation (110.1 ± 20.7 a.u.) was close to that of ganglion cell layer (112.5 ± 20.7) and outer plexiform layer (117.7 ± 19.6).
Conclusions
The hyporeflective epiretinal proliferation is a distinct entity that appears to be present in multiple vitreomacular interface disorders, particularly LMH. Further study is needed to understand its role in the pathophysiology of LMH and its implications for surgical and visual outcomes.