Scleral buckling versus primary vitrectomy in rhegmatogenous retinal detachment study (SPR study): Risk assessment of anatomical outcome. SPR study report no. 7

Purpose: The 'Scleral buckling versus primary vitrectomy in rhegmatogenous retinal detachment study' (SPR study) is a randomized multicentre trial comparing primary vitrectomy (PV) and scleral buckling surgery (SB) for rhegmatogenous retinal detachment (RRD). This subanalysis was conducted to identify risk factors associated with anatomical outcomes. Methods: Relating the anatomical success results at the 1-year follow-up visit to pre- and intraoperative findings using multivariate statistical methods. Results: In the phakic subtrial, anatomical success was negatively associated with the number of breaks (p < 0.0001), break extension > 1 clock hour (p = 0.0005) and intraoperative use of cryotherapy (p = 0.0484). It was positively associated with retinal breaks with irregular edges (p = 0.0353) and subretinal fluid drainage (p = 0.0155). In the pseudophakic/aphakic subtrial, anatomical success was negatively associated with the number of retinal breaks (p = 0.0004) and previous YAG capsulotomy (p = 0.0256), and the combined effect of the surgical procedure and intraoperative use of laser (p = 0.0229). Conclusion: Primary anatomical success is an important result for patients undergoing RRD surgery. Our data demonstrate that the final anatomical outcome is related to a higher preoperative number of breaks and cryotherapy in phakic eyes. Additional risk factors varied between phakic and pseudophakic subgroups. Our findings may be used to facilitate the prognosis of future patients with RRD.