Purpose
We conducted a retrospective comparative-effectiveness study of best-corrected visual acuity (BCVA) and refractive error (RE) following immediate sequential (ISBCS) and delayed sequential (DSBCS) bilateral cataract surgery. We tested two hypotheses: (1) among DSBCS patients, 2nd eye outcomes were no different than 1st eye outcomes; (2) averaged between each patient’s two eyes, outcomes did not differ between ISBCS and DSBCS patients.
Design
Retrospective comparative-effectiveness study.
Subjects
Kaiser Permanente Northern California members who underwent non-complex bilateral cataract surgery during 2013 through June 30, 2015.
Methods
We performed an intention-to-treat analysis comparing ISBCS to DSBCS using conditional logistic regression analysis, accounting for surgeon and patient-level factors.
Main Outcome Measures
BCVA, RE.
Results
The analysis of visual outcomes included both eyes of 13,711 DSBCS and 3,561 ISBCS patients. Because of the large sample size, some statistical differences lacked clinical significance. Ocular comorbidities were slightly more prevalent in DSBCS patients. Postoperative BCVA was 20/20 or better in 48% of DSBCS 1st eyes, 49% of DSBCS 2nd eyes, 53% of ISBCS right eyes, and 51% of ISBCS left eyes. The within-person difference in postoperative BCVA averaged zero (0.00) between the 1st and 2nd DSBCS eyes, and between the ISBCS right and left eyes. After adjustment, average postoperative BCVA was better in ISBCS patients, although the difference was not statistically significant. (compared with 20/20 or better: odds ratio for worse than 20/20 was 0.91, 95% confidence interval 0.83–1.01). Emmetropia (spherical equivalent −0.5 to 0 D) was achieved in 61% of 1st DSBCS eyes, 61% of 2nd DSBCS eyes, 63% of ISBCS right eyes, and 62% of ISBCS left eyes. After adjustment, average postoperative RE was no different in ISBCS compared with DSBCS patients (compared with emmetropia: odds ratio for ametropia was 1.02, confidence interval 0.92–1.12). We confirmed one case of postoperative endophthalmitis in 10,494 ISBCS eyes (1.0 per 10,000 eyes), two cases in 38,736 DSBCS eyes (0.5 per 10,000 eyes) (p=0.6), and no patient had bilateral endophthalmitis.
Conclusion
Compared with DSBCS cataract surgery, we found no evidence that ISBCS surgery was associated with worse postoperative BCVA or RE, or with an increased complication risk.