To estimate and compare the costs of scleral buckle (SB) and pars plana vitrectomy (PPV) for treatment of rhegmatogenous retinal detachment (RRD).
Cost analysis based on published prospective data comparing SB and PPV for RRD repair.
The costs of initial surgery, postoperative retina-affecting procedures, and eventual cataract extraction resulting from SB and PPV for RRD repair were estimated for both phakic and pseudophakic or aphakic patients and then were compared. A univariate sensitivity analysis also was performed to examine the sensitivity of our estimations.
When considering all costs, SB was 10.7% less expensive than PPV for RRD repair in phakic patients, whereas PPV was 12% less expensive than SB for RRD repair in pseudophakic or aphakic patients. These conclusions were robust in the sensitivity analysis.
SB seems to offer a modest cost savings over PPV for repair of RRD in phakic patients. However, in pseudophakic and aphakic patients, PPV seems to be less expensive than SB.
Rhegmatogenous retinal detachments (RRDs) that cannot be treated with pneumatic retinopexy usually are treated either with scleral buckling (SB) alone or pars plana vitrectomy (PPV) with or without concomitant SB. Recent data from a randomized, controlled trial suggest that both of these surgical approaches work well in phakic and pseudophakic or aphakic patients, with similar final retinal reattachment rates.
Although the clinical outcomes may be comparable between SB and PPV for RRD, other factors may affect a surgeon’s choice of one procedure over another, including personal experience, patient factors, training bias, reimbursement rate, technical difficulty, and so forth. Because of the rising costs of health care, much attention has been directed toward cost as an important consideration in medical decision making. The purpose of this study was to estimate and compare the costs of SB and PPV for treatment of RRD.
Our analyses are based entirely on published data, therefore no institutional review board approval was obtained. A societal cost perspective was assumed for this report. The clinical outcomes that serve as the basis for this analysis are derived from the only randomized clinical trial comparing SB and PPV for the repair of primary retinal detachment in both phakic and pseudophakic or aphakic patients, namely, “Scleral Buckling versus Primary Vitrectomy in Rhegmatogenous Retinal Detachment: A Prospective Randomized Multicenter Clinical Study,” abbreviated as the SPR study. To calculate an estimate for the total cost of SB and PPV for RRD, we combined the cost of initial surgery as reimbursed by Medicare with the cost of subsequent procedures needed after the initial surgery during the follow-up interval reported in the SPR study.
Medicare reimbursement rates for surgeon fees were obtained from the American Medical Association’s cpt search tool, using the national average reimbursement rates for nonfacility limiting charges. The cost of ophthalmic biometry with intraocular lens selection (Current Procedural Terminology code 76519) was included in the surgeon fee for cataract surgery. The national anesthesia conversion factor and appropriate anesthesia base units for SB, PPV, and cataract surgery from 2013 were obtained from the Centers for Medicare and Medicaid Services and were used to calculate the cost of anesthesia. Anesthesiology reimbursement also was based on surgical case length. We assumed that primary and repeat retinal detachment repairs took 2 hours to complete, cataract extraction with intraocular lens placement took 30 minutes to complete, and silicone oil removal took 30 minutes to complete. Ambulatory surgery center fees for 2013 for each procedure also were obtained from Centers for Medicare and Medicaid Services. The costs of topical medications and preoperative and postoperative visits were not included in our study because no data regarding the details of these parameters were presented in the SPR study; also, their cost likely does not differ much between patients undergoing SB and those undergoing PPV.
The SPR study presents rates of postoperative so-called retina-affecting procedures performed after initial RRD repair. However, the manuscript does not present the types or relative rates of the different procedures performed and simply implies that they include return to the operating room, additional laser photocoagulation, and intravitreal gas injection. Another SPR publication suggests that the vast majority of retina-affecting procedures in the original study were for retinal redetachment, but does not detail what types of procedures were performed. For the purposes of our study, it was assumed that 80% of postoperative procedures performed were a return to the operating room for recurrent retinal detachment repair, and the other 20% were an even mix of laser retinopexy, cryopexy, or intravitreal gas injection. Using these data, the average cost of a postoperative retina-affecting procedure was estimated and used for our analysis.
The SPR study also describes the proportion of patients undergoing silicone oil implantation, and subsequent removal, during study follow-up (in patients originally randomized to SB, this was placed during revisional surgery). Using these data, the average per-patient cost of silicone oil removal was estimated for each surgical subgroup.
The SPR study divided patients treated for RRD into phakic and pseudophakic or aphakic groups. Cataract progression in phakic patients was defined as an increase in 1.0 units on the Lens Opacities Classification System III. For the purposes of our cost comparisons, all cataract progression after RRD repair was considered to be both secondary to RRD repair and visually significant enough to require cataract surgery.
A 1-way sensitivity analysis was performed for the uncertain parameters in our cost model to evaluate how sensitive our main conclusions were to the specific values of these parameters. Specifically, each uncertain cost parameter was varied until a cost benefit of either SB or PPV was eliminated; then, the magnitude of change required for this reversal was recorded.
The total reimbursable costs of primary and recurrent RRD repair, routine cataract extraction, and silicone oil (implanted material, posterior segment) removal are listed in Table 1 . Considering initial cost alone, primary SB was less costly ($2932.32) than primary PPV ($3201.73) because of the increased surgeon fee associated with PPV. With all additional costs included, SB ($5461.66) was 10.7% less expensive than PPV ($6116.80) in phakic patients. In pseudophakic or aphakic patients, PPV ($4499.82) was 12.1% less expensive than SB ($5117.40; Table 2 ).
|CPT Code||Description||Surgeon Fee||ASC Fee||Anesthesiology Fee||Total Medicare Reimbursable|
|67107||Repair of retinal detachment; scleral buckling||$937.53||$1635.00||$350.79||$2923.32|
|67108||Repair of retinal detachment, with vitrectomy, any method||$1215.94||$1635.00||$350.79||$3201.73|
|66984||Phacoemulsification with intraocular lens implantation||$554.52||$971.02||$175.39||$1700.93|
|67112||Repair of retinal detachment, by scleral buckling or vitrectomy, on patient having previous ipsilateral retinal detachment||$1004.28||$1635.00||$350.79||$2990.07|
|67121||Removal of implanted material, posterior segment a||$955.71||$1635.00||$219.24||$2809.95|
|67101||Repair of retinal detachment, cryotherapy or diathermy||$604.77||$346.01||None||$950.78|
|67105||Repair of retinal detachment, photocoagulation||$546.77||$230.51||None||$777.28|
|67110||Repair of retinal detachment by injection of air or other gas||$658.27||$369.26||None||$1027.53|
|Initial Surgical Cost||Average Per-Patient Cost of Retina-Affecting Procedures a||Average Per-Patient Cost of Silicone Oil Removal a||Average Per-Patient Cost of Cataract Extraction||Average Total Per-Patient Cost|
|Phakic scleral buckle||$2923.32||$1622.73||$134.88||$780.73||$5461.66|
|Pseudophakic/aphakic scleral buckle||$2923.32||$1983.34||$210.74||$0.00||$5117.40|
The average cost of a post-operative retina-affecting procedure was calculated to be $2575.76. According to the SPR study, patients who underwent SB for RRD required more postoperative retina-affecting procedures on average than patients treated with PPV. For phakic patients initially treated with SB, an average of 0.12 more retina-affecting procedures were required per patient than PPV. For pseudophakic or aphakic patients initially treated with SB, an average of 0.34 more retina-affecting procedures were required per patient than for patients initially treated with PPV. Based on our cost estimations, this increased the average cost of SB for phakic and pseudophakic or aphakic patients more than it did the average cost of PPV ( Table 2 ).
In the SPR study, silicone oil tamponade was used in 9.1% of phakic eyes originally randomized to undergo SB (during revisional surgery), and in 17.9% of eyes randomized to PPV, and it was removed from 53% and 57% of eyes initially randomized to SB and PPV, respectively. In the pseudophakic or aphakic group, 21.8% of SB patients eventually had silicone oil placed, as compared with only 11.3% of eyes undergoing initial PPV, with 34.5% and 60% removed in the pseudophakic or aphakic scleral buckle and PPV groups, respectively, by the end of the study. The average per-patient cost of silicone oil removal was based on those patients whose oil was removed by the end of the SPR study ( Table 2 ).
During the follow-up period of the SPR study, cataract progressed in 45.9% of phakic patients initially treated with SB and in 77.3% of phakic patients initially treated with PPV. The cost of routine cataract extraction and intraocular lens implantation is outlined in Table 1 . The estimated per-patient cost of cataract surgery after retinal detachment repair, based on the data, is presented in Table 2 .
Table 3 shows the details of our 1-way sensitivity analysis. The analysis revealed that our conclusions regarding the cost of SB compared with PPV are quite robust despite possible inaccuracy of our cost assumptions. In particular, our assumption that 80% of retina-affecting procedures were a return to the operating room for retinal detachment repair (as opposed to 20% that were intravitreal gas injection, laser retinopexy, or cryopexy) could be varied significantly in either direction with our conclusions remaining unchanged. Indeed, our conclusions regarding cost in phakic patients were most sensitive to variability in the proportion of postoperative retina-affecting procedures in patients initially randomized to PPV that constituted a return to the operating room, but this variable would have to decrease by 40% before PPV became less expensive than SB in this group. Our conclusions regarding cost in the pseudophakic or aphakic group were most sensitive to variability in the number of retina-affecting procedures per patients initially randomized to undergo SB, but this would need to decrease by 31.2% before SB became less expensive than PPV in that group.
|Baseline Value||Inflection Point a||Change from Baseline (%) b|
|Phakic retinal detachment (baseline = scleral buckle less expensive)|
|RAP = RD repair in OR||0.80||>1||N/A|
|RAP = RD repair in OR||0.80||0.48||40|
|Pseudophakic retinal detachment (baseline = vitrectomy less expensive)|
|RAP = RD repair in OR||0.80||0.50||37.5|
|RAP = RD repair in OR||0.80||>1||N/A|