Sensory Retinal Layer Thickness May Predict Vision Loss After PDT

Pretreatment sensory retinal layer thickness may be able to predict vision loss following photodynamic therapy (PDT) for central serous chorioretinopathy (CSC), according to a study published in the American Journal of Ophthalmology. 

Researchers included 85 eyes with CSC that successfully underwent PDT to resolve a serous retinal detachment in the retrospective, single center investigation. Study participants underwent a complete eye examination, fundus photography, scanning laser ophthalmoscopy, spectral domain-optical coherence tomography (SD-OCT), optical coherence tomography-angiography (OCT-A), fluorescein angiography, and indocyanine green angiography. The investigators determined the incidence of vision loss among the cohort and identified associated baseline characteristics.

Overall, 20% of eyes (n=17) experienced worse vision at 6 months following the procedure compared with baseline, the report shows. Individuals who experienced vision maintenance or improvement following PDT had better vision at 1 month (0.16 vs 0.45 logarithm of the minimum angle of resolution [logMAR]), 3 months (0.10 vs 0.34 logMAR), and 6 months (0.08 vs 0.47 logMAR) compared with participants who experienced vision loss (P <.001 for all).

Thinner preprocedural sensory retinal layer thickness was associated with worse postprocedural vision, the report shows. Mean neurosensory retinal thickness (123.2 vs 166.3 μm; P <.001), internal limiting membrane-external limiting membrane thickness (IET; 63.1 vs 88.0 μm; P <.001), and external limiting membrane-photoreceptor outer segment thickness (EOT; 60.1 vs 78.3; P =.041) were thinner among individuals with postprocedural vision loss compared with postprocedural vision maintenance or improvement.

The sensitivity, specificity, positive predictive values, and negative predictive values for vision loss were 94.1%, 50.0%, 32.0%, and 97.1% for sensory retinal layer thickness, 94.1%, 51.5%, 32.7%, and 97.2% for IET, and 94.1%, 30.9%, 25.4%, and 95.5% for EOT, according to the report.

“[U]sing pretreatment neurosensory retinal layer thickness in patients with CSC would enable the classification of cases of vision loss after PDT with high accuracy,” according to the researchers. “Using these OCT findings as a reference for PDT may allow for interventions for patients with CSC before they present with poor vision after PDT.”

Study limitations include a small sample size, short study duration, single center design, and retrospective nature.