Preoperative duration of retinal detachment and subretinal immunoreactive endothelin-1: repercussion on logarithmic visual acuity

To analyze whether preoperative duration of primary rhegmatogenous retinal detachment (RD) influences endothelin-1 (ET-1)-a vasoactive, mitogenic, and pro-apoptotic peptide- levels with repercussions on logarithmic (LogMAR) visual acuity (VA). Prospective clinical cohort study on 66 healthy patients [33 with proliferative vitreoretinopathy (PVR) and 33 with no PVR] with unilateral RD candidates for scleral buckling (SB) surgery. Using radioimmunoassay, immunoreactive ET-1 (IR-ET-1) was tested in both plasma and subretinal fluid (SRF) of these RD patients. Pearson's correlations were evaluated between preoperative RD duration and each IR-ET-1 level (plasma, SRF and the difference SRF minus plasma) and also between both variables and the LogMAR VAs (preoperative, postoperative 8 months, and the difference: postoperative 8 months minus preoperative). PVR was associated with higher preoperative RD duration, higher LogMAR VA values (pre- and postoperative 8 months) and higher IR-ET-1 values (plasma, SRF and the difference: SRF minus plasma) than no-PVR IR-ET-1 levels (plasma and SRF) were only correlated (r = 0.462, p = 0.007; r = 0.397, p = 0.022 respectively) with preoperative RD duration in the no-PVR group. IR-ET-1 values (plasma, SRF and the difference:SRF minus plasma) showed statistically significant correlations with pre- and with postoperative 8 months LogMAR VAs in no-PVR and with postoperative 8 months LogMAR VA and LogMAR VA difference in PVR The highest correlation between IR-ET-1 levels and LogMAR VAs was found between SRF IR-ET-1 and postoperative 8 months LogMAR VA in PVR (cases with macula-on) (r = 0.956, p < 0.0001). Preoperative RD duration showed statistically significant positive correlations with pre- and with postoperative 8 months LogMAR VAs in both the no-PVR and the PVR groups and with IR-ET-1 measurements (plasma and SRF: lower correlations) only in the no-PVR group. These findings support the idea of doing primary and prompt vitrectomy for RD and perhaps using coadjutant pharmacologic therapy in order to improve visual results.