ObjectiveTo observe the occurrence and evolution of persistent submacular fluid (SMF) after scleral buckling surgery (SB) in rhegmatogenous retinal detachment, and then to study the related factors of persistent SMF and the effect of persistent SMF on visual outcome. MethodsNinety eyes of 89 patients with rhegmatogenous retinal detachment which had been performed SB were included in this study. Best corrected visual acuity (BCVA), intraocular pressure, slit-lamp microscopy, three mirror contact lens, indirect ophthalmoscopy and B-scan ultrasonography were measured for all patients. There were 21 eyes with atrophic holes while 42 eyes with horse-shoe tears, 22 eyes with old retinal detachment while 68 new suffered eyes. Thirty-two eyes underwent scleral encircling surgery (SE) and 58 eyes underwent segmental scleral buckling surgery (SSB). The patients were divided into SMF group and non-SMF (NSMF) group according to the results of optical coherence tomography (OCT) at 1 month postoperatively. Thorough ophthalmologic examinations were performd at 1, 3, 6 and 12 months after surgery to the patients, further observations were continued to carry out unless the abnormality had resolved for at least 6 months. ResultsPatients who underwent SE (20 eyes, 62.5%) had a higher incidence of persistent SMF at 1 month after surgery than those who underwent SSB (23 eyes, 39.7%), the difference was significant (χ2=5.024, P < 0.05). Persistent SMF was more frequent in eyes with atrophic holes (66.7%) than that with horseshoe tears (38.1%), the difference was significant (χ2=4.582, P < 0.05). Persistent SMF was found in 72.7% old retinal detachment eyes and in 39.7% new suffered eyes, showed a striking differences (χ2=7.264, P < 0.01). There was no significant difference in BCVA among SE and SSB groups at every time point (t=0.659, 0.699, 1.108, 1.037, 1.902; P > 0.05). The SMF group have a similar BCVA with NSMF group 1 and 3 months after surgery (t=1.812, 1.957; P > 0.05), whereas the SMF group showed worse BCVA than NSMF group from since 6 months after surgery (t=2.324, 2.147, 2.184; P < 0.05). ConclusionsPersistent SMF is more frequent after SE than SSB, the type of retinal breaks and old retinal detachment may be the potential influencing factors. Persistent SMF after SB may affect the final visual outcome.