Abstract
Purpose :
To analyze the ellipsoid zone (EZ) on Optical Coherence Tomography (OCT) in patients who underwent pars plana vitrectomy with membrane peeling for repair of an idiopathic macular hole.
Methods :
All patients who had successful closure of an idiopathic macular hole after pars plana vitrectomy at the George Washington University Department of Ophthalmology and the Virginia Retinal Center between January 1, 2012 and July 1, 2015, and who had been followed for at least six months, were identified. The EZ intensity was analyzed using the National Institutes of Health's (NIH) Medical Imaging, Processing, Analysis, and Visualization (MIPAV) software. Volumes of Interest (VOIs) were drawn at predefined intervals over the EZ of both the surgical and contralateral control eye, and average voxel intensity was recorded (Figure 1). To account for variability in signal quality and intensity from scan to scan, additional VOIs were drawn on the Retinal Pigment Epithelium (RPE) directly beneath each EZ VOI to serve as an internal control; the ratio of each respective Ellipsoid VOI to RPE VOI (EZ/RPE ratio) was used for analysis.
Results :
Ten patients were included in our study with results shown in Figure 2. Average visual acuity within six months after hole closure was 43 and 81 ETDRS letters for the surgical and control eyes, respectively. Average EZ/RPE ratio within six months after hole closure was 0.42 and 0.81 for the surgical and control eyes, respectively. Average visual acuity six to 12 months after hole closure was 38 and 80 ETDRS letters for the surgical and control eyes, respectively. Average EZ/RPE ratio six to 12 months after hole closure was 0.46 and 0.86 for the surgical and control eyes, respectively, which represents a decrease of 87.6% (p<0.01) in the ellipsoid zone for the surgical eyes compared to the control eyes.
Conclusions :
The ellipsoid zone does not fully recover after macular hole closure in eyes that have undergone pars plana vitrectomy and is significantly decreased compared to the contralateral unaffected eye, correlating to a decrease in visual acuity.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.