Surgical induced astigmatism in phaecoemulsification cataract surgery
Purpose: Surgical induced astigmatism is often-neglected issue in phaecoemulsification cataract surgery. It is a significant problem resulting in poor refractive outcome and patients’ satisfaction. The objective of this study was to describe the preoperative astigmatism and the postoperative surgical induced astigmatism and its contributing factors.
Design: Retrospective study on the Malaysian Cataract Surgery Registry between year 2008 and 2011.
Method: Data on phaecoemulsification cataract surgery from 37 Ophthalmology Units were studied and filtered. Patients more than 50 year-old with complete refractive assessment results and with no ocular comorbidity were included. Contributing factors namely patients’ age, race, gender, laterality of the operated eye, surgeon’s status and intraoperative complications were analyzed.
Results: The mean age of the 5350 patients was 68.0 years with majority Chinese patients. The mean postoperative cylinder was 1.19D (SD=0.91) compared to the preoperative mean cylinder of 0.88D (SD=0.83D). Multivariate regression analysis on postoperative data revealed statistically significant high cylinder power (>1.0 Dioptre) for older patients, Chinese race, left operated eyes (p<0.001), performed by trainee ophthalmologists (p<0.001), and for those with intraoperative complications (p<0.001). The overall difference of cylinder power before and after phaecoemulsification cataract surgery was high; signifying high degree of surgical induced astigmatism.
Conclusion: Surgical induced astigmatism could result in significant postoperative astigmatism with poor refractive outcome. The contributing factors are old age, Chinese race, left operated eyes, operated by trainee ophthalmologists and intraoperative complications.