Natural History Of Persistent Subretinal Fluid Following The Successful Repair Of Rhegmatogenous Retinal Detachment

AIM: To provide a detailed description of the natural history of persistent subretinal fluid (SRF) after successful repair of rhegmatogenous retinal detachment (RRD) and its association with visual outcome.METHODS: This was a prospective long-term follow-up for eyes undergoing scleral buckling (SB) surgery for maculaoff RRD. Examinations were carried out preoperatively and postoperatively at 1, 3, 6, 9 and 12mo, until persistent SRF had completely resolved. One month postoperatively, optical coherence tomography (OCT) was used to classify SRF into three patterns: bleb-like loculated (BL), shallow-diffused (SD), and multiple blebs (MB). Serial OCT imaging was used to evaluate morphological changes in SRF until its complete disappearance. Patients were divided into two groups depending on the presence or absence of persistent SRF.RESULTS: A total of 59 patients (59 eyes) were included. There were no statistical differences between two groups at baseline, except for the proportion of patients with high myopia and a younger age. One month after surgery, OCT detected persistent SRF in 49 eyes (83.1%). The 3 morphological patterns of SRF were observed in 27 eyes (55.1%) with BL, 13 eyes (26.5%) with SD, and 9 eyes (18.4%) with MB. The mean time for complete absorption differed significantly across the three SRF patterns (F=8.097, P=0.001), which was 8.8 +/- 6.1, 20.1 +/- 12.1, and 16.7 +/- 10.2mo in BL, SD, and MB, respectively. In 9 of the 13 eyes with SD, the pattern transformed into MB type. In cases involving MB, the size and number of blebs decreased gradually until they had been completely absorbed. Eyes with persistent SRF were more likely to demonstrate disruption of the ellipsoid zone (49.0% vs 10%, P=0.034). The final best-corrected visual acuity of two groups was 0.37 +/- 0.11 (with SRF) vs 0.34 +/- 0.12 (without SRF) logMAR (P=0.499), respectively.CONCLUSION: High preoperative myopia and younger age are associated with persistent SRF. BL is the most commonly observed pattern with the shortest duration and gradually disappeared. Most cases involving SD SRF transform into MB type during resolution. The size and number of the MBs decrease gradually until they were completely absorbed. The absence of persistent SRF may contribute to slow visual recovery in the short-term but does not influence the final visual outcome.