Correlation between retinal sensitivity assessed by microperimetry and OCT findings after epiretinal membrane surgery

Abstract

Purpose : To verify the correlation between retinal sensitivity (RS) assessed by microperimetry (MP3, Nidek) and optical coherence tomography (swept-source OCT, Topcon) parameters in eyes submitted to the epiretinal membrane (ERM) and peeling of internal limiting membrane (ILM) surgery.

Methods : 30 eyes underwent posterior vitrectomy for ERM treatment. Best-corrected visual acuity (BCVA) and 3D volumetric OCT imaging were preoperatively acquired. 6 months after the surgery, BCVA, OCT imaging, and RS were assessed. Analyzed OCT parameters included: the total macular and the ganglion cell layer complex (GCC) thickness. Cysts, disorganization of retinal inner layers (DRIL), and changes of the outer retina were assessed.MP3 parameters tested were 44 points covering 20 central degrees, with direct correspondence with the 9 sectors of ETDRS map.

Results : RS parameters were significantly lower in patients. The total macular thickness measurements were thicker than controls preoperatively and significantly reduced postoperatively. Preoperative GCC measurements were higher than controls, showing a significant reduction postoperatively and were significantly lower when compared to controls. Eyes with lower RS in the fovea were correlated with the preexisting DRIL. Lower MP3 RS values were associated with DRIL, outer retinal changes, and cysts after surgery.

Conclusions : Macular thickness measurements remains thicker after ERM surgery. GCC thickness was significantly reduced after surgery, suggesting an atrophy of this layer. Despite the great visual improvements, the RS parameters were significantly lower. DRIL, outer retinal changes, and cysts were poor prognostic factors for visual function recovery after ERM surgery.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.

 

Table 1:Postoperative microperimetry retinal sensitivity measurements mean values.
Table 2:Mean ± SD of postoperative microperimetry retinal sensitivity and its correlation with pre and postoperative OCT findings.

 

A: Example of an MP3 scan of the right eye of a patient with ERM with 44 points by MP3 covering the central 10 degrees in direct correspondence with the 6 mm diameter OCT-ETDRS map centered on the fovea. B: Same patient represented in A, with distribution with the reference measures in degrees of the 44 points tested. C: Each point tested presents the value of the retinal sensitivity measured in dB in a direct correspondece with the OCT-ETDRS map (in microns).