Influence of drainage retinotomy on anatomical and visual outcomes of pars plana vitrectomy for primary rhegmatogenous retinal detachment

Abstract

Objectives: To assess the influence of drainage retinotomy (DrR) on anatomical and visual outcomes of pars plana vitrectomy (PPV) for primary uncomplicated rhegmatogenous retinal detachment (RD), compared with drainage through pre-existing retinal break (PRB).

Methods and analysis: Retrospective study on patients treated with PPV for RD. Prospectively collected data were extracted from the Britain & Eire Association of Vitreoretinal Surgeons and European Society of Retina Specialists (EURETINA) RD database, including baseline features, surgical details, and anatomical and functional outcomes. Inclusion criteria were as follows: uncomplicated PPV, gas tamponade, drainage through DrR or PRB, surgeons with >100 cases recorded. Exclusion criteria were as follows: age <16, <2-month follow-up, ocular comorbidity, proliferative vitreoretinopathy ≥grade C, giant retinal tear, tamponade other than gas. Full propensity score matching resulted in matched groups to mitigate confounding bias. Subsequent multivariable linear regression was performed for postoperative best-corrected visual acuity (BCVA) as dependent variable, and Firth penalised logistic regression with DrR, single-surgery anatomical success (SSAS), epiretinal membrane (ERM) and macular fold as dependent dichotomised variables on matched data.

Results: Of 12 504 eyes extracted, 4175 were included. Of these, 3432 (82.2%) had PRB drainage (non-DrR group) and 743 (17.8%) a DrR (DrR group). Final median (IQR) BCVA was 0.18 (0.14-0.48) in the non-DrR group and 0.20 (0.18-0.48) in the DrR group (p=0.072). SSAS rate was 93.4% and 91% (OR 0.71 (95% CI 0.54 to 0.95)) and postoperative ERM rate 1.6% and 4.2% (OR 2.63 (95% CI 1.68 to 4.10)) in the non-DrR and DrR groups, respectively. On multivariable regression, DrR was associated with postoperative ERM (p=0.011), but not with final BCVA, SSAS and macular folds (p=0.633, 0.149 and 0.085, respectively).

Conclusion: Our study confirmed the association between DrR and increased risk of developing ERM; however, DrR does not appear to impact significantly on other outcomes.

Keywords: Retina; Treatment Surgery; Vitreous.

Figure 1. (A) Multivariable Firth logistic regression model found that greater RD extent, macular detachment, round hole-RD (U-tear reference) and pseudophakic RD were significantly associated with greater likelihood of performing a DrR. Worse preoperative BCVA, PVR B and isolated superior RD were significantly associated with less DrR. (B) Bar chart to demonstrate proportion of DrR performed by user. Significant values in bold. BCVA, best-corrected visual acuity; DrR, drainage retinotomy; PVR, proliferative vitreoretinopathy; RD, retinal detachment; VA, visual acuity; RRD, rhegmatogenous retinal detachment.

Figure 2. Multivariable Firth penalised logistic regression regarding risk of (A) redetachment: identified that combined phacovitrectomy and pseudophakic RD lead to reduced retinal redetachment. Increased extent of RD, more inferior retinal breaks, high myopia and being pseudophakic post-op were significant risk factors for redetachment; (B) ERM formation: demonstrated pseudophakic RD and high myopia lead to less ERM formation, while DrR, increased break size and postoperative pseudophakia lead to increased ERM; (C) macular fold formation: short-acting gas tamponade, female sex, more inferior breaks and isolated superior RD were associated with increased risk of macular folds. Significant values in bold. ERM, epiretinal membrane; PCIOL, posterior chamber intraocular lens; PVR, proliferative vitreoretinopathy; RD, retinal detachment; RRD, rhegmatogenous retinal detachment; SSAS, single-surgery anatomical success; VA, visual acuity.

Figure 3. Box and whisker plot comparing BCVA between no DrR and DrR. On univariable analysis: (A) across the whole cohort, the DrR group had significantly worse preoperative BCVA, increased logMAR gain and no difference in FU BCVA. (B) In subgroup of foveal-detached eyes, the DrR group had significantly better preoperative BCVA, reduced logMAR gain and no difference in FU BCVA. Significant values in bold. BCVA, best-corrected visual acuity; DrR, drainage retinotomy; FU, follow-up; VA, visual acuity.