Cost Drivers of Pars Plana Vitrectomy for Retinal Detachment: Time-Driven Activity-Based Costing Analysis

Introduction: To determine drivers of day-of-surgery costs for pars plana vitrectomy (PPV) in the management of retinal detachment (RD) repair, the mainstay treatment, based on surgical complexity and intraoperative factors. Methods: Economic analysis was performed using time-driven activity-based costing methodology for patients who had standard (Current Procedural Terminology [CPT] code 67108) or complex (CPT 67113) RD repair with PPV at the University of Michigan in 2021. Data were obtained via the electronic health record and previous literature. PPV expenses were determined with time-driven activity-based costing, a cost calculation that incorporates time and key resource costs, and were analyzed using univariate and multivariate regression. Results: The analysis included 412 PPVs (270 standard and 142 complex based on CPT code). The operating room time was significantly increased in complex cases (P < .01). Univariate analysis found that complex PPV, cryopexy, staining agent use, retinectomy, simultaneous scleral buckling, perfluoro-N-octane (PFO) use, silicone oil tamponade, and perfluoropropane tamponade were associated with a statistically significant difference in costs (P < .01); use of laser retinopexy was not significantly associated (P = .7190). Multivariate analysis found that standard PPV cost an average $5132.33, and significant incremental costs were found for complex PPV (+$1185.55; P < .001), cryopexy (+$465.02; P = .032), staining (+$525.16; P = .04), PFO use (+$1089.54; P < .0001), retinectomy (+$2031.17; P < .0001), and simultaneous scleral buckling (+$916.34; P = .006). Conclusions: The intraoperative factors that increase operating room time and ultimately the incurred cost of complex PPV cases vs standard PPV were identified and economically defined. These findings can improve practice patterns by optimizing costs for effective surgical planning in the management of RD repair.