Prognostic Value of Interocular Flicker ERG Asymmetry in Acute Postoperative Endophthalmitis After Intraocular...

Postoperative endophthalmitis remains a vision-threatening complication despite advances in treatment. Current prognostic markers (Gram stain and initial visual acuity) have limited predictive values for real-time retinal neuronal function assessment and visual recovery. The purpose of this pilot study was to explore whether photopic electroretinograms might be used to forecast the endophthalmitis prognosis following intravitreal injection or phacoemulsification intraocular lens implantation.

This prospective observational study included 11 consecutive patients with acute postoperative endophthalmitis following phacoemulsification with IOL implantation (3 eyes) or intravitreal injections (8 eyes). ERGs were recorded using a portable RETeval™ system under nonmydriatic conditions. R Core Team (2019) was used to assess the preoperative electroretinogram outcomes, duration until the onset of endophthalmitis, procedure types of original surgeries, and pre- and postoperative best-corrected visual acuity.

Mean patient age was 79.23 years (range 62-88). A significant correlation was found between interocular photopic flicker latency difference and BCVA improvement (p = 0.04, < 0.05). Patients with ≤ 8 ms latency difference showed significantly better visual recovery (≥ 2-line gain). No significant correlations were found with diabetes status, original surgical procedure types, or time to symptom onset.

In this hypothesis-generating pilot study of acute postoperative endophthalmitis, a smaller interocular flicker ERG latency difference at presentation is associated with better visual recovery. These preliminary findings suggest that this rapid, noninvasive functional test may have potential as a prognostic biomarker and warrants further validation in larger cohorts, complementing existing clinical and microbiological parameters in the management of this sight-threatening infection.