Scleral buckling versus primary vitrectomy in rhegmatogenous retinal detachment study (SPR study): multiple-event analysis of risk factors for reoperations. SPR Study report no. 4.
PURPOSE
To identify risk factors that may lead to reoperations following primary vitrectomy (PV) and scleral buckling surgery (SB) for rhegmatogenous retinal detachment (RRD).


METHODS
Analysis of the association between distinct parameters and the necessity for reoperations in the 'Scleral buckling versus primary vitrectomy in rhegmatogenous retinal detachment study' (SPR Study) using an Andersen-Gill-mean intensity model.


RESULTS
The risk for recurrent reoperations is significantly reduced by primary vitrectomy (PV) compared to scleral buckling (SB) in pseudophakic eyes (p = 0.0009) and increased after PV compared to SB in phakic eyes (p < 0.0001). Additional significant risk factors were in the pseudophakic group preoperative deterioration of visual acuity (p = 0.0226), YAG capsulotomy (p = 0.0043), large breaks (p = 0.0290), number of affected quadrants (p = 0.0387), retinal incarceration during surgery (p = 0.0115), number of breaks (p < 0.0001) and symptomatic visual field defect (p = 0.0463). In the phakic group, associated risk factors were low intraocular pressure (p = 0.0013) and persistent intraoperative detachment at the buckle (p = 0.0184).


CONCLUSION
Reoperations are used as an indicator for the quality and efficacy of surgical techniques. Using a refined multivariate survival model, distinct factors were identified and associated with one or more reoperations after PV or SB in RRD surgery. This information should be useful in the decision process regarding the surgical approach.