Is There a Correlation Between DMD and Visual Outcomes After RRD Repair?

There is considerable debate regarding the allowable duration of time prior to surgical intervention for macula-involving retinal detachments. Many prior studies recommend surgery within one week of detachment, with a range of 2 days to 2 weeks published in the literature. The authors argue that these studies may be limited by sample size and their retrospective nature. They sought to find a better understanding of the impact of duration of macular detachment (DMD) on visual prognosis.

This prospective observational cohort study sought to determine a correlation between DMD and visual outcomes after rhegmatogenous retinal detachment (RRD) repair. A total of 719 eyes with macula-off RRD performed between February 2016 and March 2017 queried from the Japan-Retinal Detachment Registry were included. Notably, demographics data for all patients in this registry were prospectively registered prior to surgical intervention. Outcomes were compared 6 months postoperatively, with best corrected visual acuity (BCVA) at 6 months as a primary endpoint. Five comparisons were performed: surgery within N days from the onset of macular detachment versus surgery after N+1 days from the onset of macular detachment (N= 2 to 5 days). Eyes with prior ocular surgery other than cataract surgery, pars plana vitrectomy, and surgery for prior RD were excluded.

Six months after surgery, BCVA was significantly better in patients whose retinal detachment repair occurred within 2 days of macular detachment onset as compared to those whose macular detachment lasted 3 days or longer (P = 9.1 × 10–7). Similarly, if the DMD was 3 days or less the BCVA was statistically significantly better in comparison to 4 days or more (P = 1.6 × 10–3). Comparisons of surgeries performed within 4 days of the onset of macular detachment versus those performed after 5 days and those performed within 5 days of the onset of macular detachment versus those performed after 6 days also revealed better acuity with earlier surgery, but the differences were not statistically significant.

The authors discuss that their findings are compatible with previous retrospective studies, as well as RD models that show that cone cells initiate apoptosis within 1 day of RD and peak at approximately 3 days. They argue that their large sample size, the comprehensive data from the Japan-Retinal Detachment Registry, and their method of statistical analysis to adjust for background imbalances (such as influences of institutional preferences, preoperative visual function, and the nature of the RD) makes their study unique in comparison to retrospective reviews.

Limitations of this study include that DMD was based on the patient's complaint and, therefore, is an imprecise measure that may have introduced bias. In addition, patients with a prior history of vitrectomy for any reason (including macular pathology and previous macular RDs) were included and may have affected the results, as prior macular status was not discussed. Lastly, data were only recorded up to 6 months postoperatively, and true final visual acuity is unknown.

In conclusion, the authors note that their findings support RD repair within 2 to 3 days of macular detachment yields the best BCVA at 6 months, while the timing of surgical intervention did not significantly impact visual prognosis with DMD between 4 to 6 days. The authors encourage consideration of earlier surgical treatment of macula-involving RDs when social circumstances, including access to OR time and resources, allow.