CATARACT PATIENTS IN A DEFINED SWEDISH POPULATION 1986-1990 - VIII - POSTOPERATIVE ASTIGMATISM, INTRAOCULAR-PRESSURE AND VISUAL-ACUITY

Purpose: Cataract surgery is often followed by a certain amount of ast igmatism that changes in the postoperative period. However, there are large variations in both size and changes of the postoperative astigma tism. I have analysed the variations and the influence of different ex planatory variables on the postoperative astigmatism. Methods: Data fo r all patients undergoing cataract surgery from 1986 up to and includi ng 1990 in the Lund Health Care District were prospectively recorded. Except for cases operated on with both keratoplasty and cataract, all cases were included in the study. The different explanatory variables considered included sex, age, preoperative axial length, preoperative average keratometry, preoperative intraocular pressure, glaucoma histo ry, diabetes history, uveitis history (including both anterior and pos terior uveitis), and a history of rheumatoid arthritis. Results: Besid es age and sex, several variables significantly influenced the develop ment of size and/or change in the postoperative astigmatism. They were preoperative astigmatism (polar value), preoperative intraocular pres sure, and whether or not the cataract patient had an insulin dependent diabetes. Phacoemulsification as extraction mode, the location of the incision, complications at surgery, and whether or not a sphincteroto my was performed also influenced the two parameters of astigmatism. It was also important whether or not the operation was performed by a hi gh volume surgeon. Conclusion: In this material, the most important pr edisposing factors for rapid changes in the postoperative astigmatism were large preoperative astigmatism (polar value), young age, low preo perative intraocular pressure, if an ECCE were chosen as the extractio n type, and the surgeon. The same variables and, in addition, if the l ocation of the incision was anterior to the limbus were the most impor tant explanatory variables in generating an early, large with-the-rule astigmatism.