[Clinical survey and analysis of persistent submacular fluid on optical coherence tomography after surgery for rhegmatogenous retinal detachment].

OBJECTIVE

To investigate the incidence, duration and consequences of persistent submacular fluid after pars plana vitrectomy (PPV) and scleral buckling surgery (SB) in rhegmatogenous retinal detachment, thus to explore the clinical association between persistent SMF and different surgical methods, and simultaneously, to study the effect of persistent submacular fluid on visual outcome.

METHODS

It was a retrospective case-series study. Ninety-two qualified eyes including 54 eyes of males and 38 eyes of females with rhegmatogenous retinal detachment which had been performed PPV or SB were recruited. The average age of the patients was (45.8 ± 15.3) years with a age-range from 15 to 76 years. The inclusion criteria was as follows, the macula-off rhegmatogenous retinal detachments without macular hole and obvious proliferative vitreoretinopathy, the retina was completely reattached 1 month after operation and no redetachment was found by ophthalmoscope and B scan till the last follow-up, the minimal follow-up time was 1 year and the submacular fluid must have been dissolved for at least 6 months. All patients underwent thorough ophthalmologic examinations before and after operation, Those patients in whom a persistent submacular fluid was seen on optical coherence tomography (OCT) at 1 month after operation performed follow-up with repeat of the investigations at 3, 6 and 12 months after surgery, If the abnormality resolved, further observations were continued to undertake for 6 months or more till the last follow-up.Rank-sum test, χ²-test and Fisher exact test were applied respectively to analyze for statistical analysis.

RESULTS

The incidence of persistent submacular fluid at 1 month after surgery in the PPV and SB group was 13.9% (5/36) and 48.2% (27/56).Six months later however, the figure expressed as percentage was 2.8% (1/36) and 23.2% (18/28) correspondingly. Persistent submacular fluid was more frequent in eyes with inferior breaks (64.3%) than that with superior ones (13.9%), making a significant differences (χ² = 17.38, P < 0.01) . The persistent submacular fluid group showed worse best-corrected visual acuity than no persistent submacular fluid group 6 and 12 months after surgery (t = 2.525, t = 2.254, both P < 0.05). Comparing the visual acuity (VA) between the eyes with or without persistent submacular fluid 6, 12 months after surgery and the latest followed-up among the ever suffered eyes, a statistically significant differences presented in late stages(average VA: 0.47 ± 0.29, 0.30 ± 0.16; 0.44 ± 0.28, 0.27 ± 0.15;0.42 ± 0.22, 0.27 ± 0.19; t = 2.114, 2.207, 2.068; all P < 0.05), though there were no significant differences in the first three months (average VA: 0.70 ± 0.33, 0.63 ± 0.37; 0.50 ± 0.25,0.45 ± 0.22; t = 0.556, 0.601; both P > 0.05).

CONCLUSIONS

Persistent submacular fluid presents in both surgical procedures but it is more frequent after buckling surgery than vitrectomy, the selection of patients, the location of retinal breaks and the duration of detachment may be the potential influencing factors. Persistent submacular fluid after retinal detachment surgery is responsible for delayed recovery, and may affect the final visual outcome. The longer it lasts, the more harm may it do.