Predictive Value of Pachyvessels in Patients with Central Serous Chorioretinopathy (CSCR) Treated by Photodynamic Therapy (PDT)

Abstract

Purpose : To establish an automatic quantification method of pachyvessel area in patients with central serous chorioretinopathy (CSCR) and to evaluate predictive value of pachyvessel area for successful treatment by half-dose photodynamic therapy (PDT).

Methods : All patients who received a PDT in the Eye Department of the University of Cologne between 01.08.2015 - 01.09.2018 were retrospectively analyzed (n=146). Only therapy-naïve CSCR patients with good quality of indocyanin green angiography (ICGA) at baseline, and with a follow-up within 1-3 months after first half-dose PDT were included. Presence of pachyvessels (defined as dilated choroidal vessel) was qualitatively evaluated on ICGA frames within 6 mm grid (manually centered on the fovea). Thickest choroidal vessel diameter above the lesion was measured manually using Heidelberg Engineering Heyex Software (Version 1.10.2.0). Automatic quantitative analysis of the choroidal vessel area based on ICGA pictures (from injection up to 1:30 minutes) was done with Fiji Image J Processing Package (Version 2.0.0, trainable weka segmentation plugin) after manual training. Therapeutic success was defined as at least 50% reduction of subretinal fluid height after one PDT.

Results : Thirthy-nine eyes of 36 patients (male n = 28 (71.8%), female n= 11 (28.2%), mean age of all 53.28.4 years) of whom three where affected in both eyes fitted all above defined criteria. All patients showed visible dilated choroidal vessels (pachyvessels) within 6 mm grid. Eighteen patients (46.2 %) showed therapy response after half-dose PDT. Pachyvessel diameter above the lesions ranged from 132 μm to 317 μm, whereas pachyvessel area ranged from 15.83 mm² to 27.67 mm². Pachyvessel diameter and pachyvessel area were positively correlated (p=0.005, r=-0.438). Smaller pachyvessel area was positively associated with a successful outcome after half-dose PDT (mean pachyvessel area in responders 20.93 ± 2.71 mm²vs. in non-responders 23.24 ± 4.02 mm², p = 0.046).

Conclusions : Measurement of pachyvessel area and thickness via ICGA may be an useful tool to predict therapy response to half-dose PDT in CSCR patients.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.