Abstract
Purpose:
To describe the pre-surgical findings in epiretinal membrane using optical coherence tomography. To analize the relationship between the photoreceptor layer, central foveal thickness, presence of cysts and foveal contour alterations in order to determine their predictive value on final visual acuity.
Methods:
Patients with the following features were included: patients which underwent 23G caliber vitrectomy with diagnosis of epiretinal membrane, best corrected visual acuity of 20/60 or worse and associated metamorphopsias. All patients underwent optical coherence tomography before and after the surgery followed by a description of the findings for their analysis.
Results:
A total of 17 patient, mean age 66 SD 11 years were analyzed. The results obtained by OCT before surgery were divided in 3 groups: 11 eyes(65%) showed no photoreceptor layer disruption, 3 eyes (18%) which presented disruption of the photoreceptor layer consisting of less than 200 microns and 3 eyes (18%) presented a disruption larger than 200 microns. A statistically significant difference among the three groups before surgery in visual acuity, central foveal thickness and the presence of cysts was found, with a value of P = 0.047, 0.023 and 0.001 respectively. After surgery a statistically significant improvement in visual acuity and central foveal thickness was found in the three groups with a P value <0.05. The statistically significant predictive variable on post-surgical visual acuity was the central foveal thickness (P = 0.008) and the model which resulted statistically significant was the central foveal thickness associated with disruption of photoreceptor layer (P = 0.027).
Conclusions:
Our study demonstrated that eyes which did not present photoreceptor disruption were associated with better visual results before and after surgery compared to those which presented some degree of disruption. We found that the variables with the strongest predictive value related to visual acuity before and after surgery are central foveal thickness a photoreceptor layer disruption. We also demonstrated that the risk factors before surgery that were most strongly related with poor visual results are de presence of cysts and photoreceptor layer disruption larger than 200 microns.
Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
688 retina •
762 vitreoretinal surgery