Temporary Haptic Externalization and Four-point Fixation of Intraocular Lens in Scleral Fixation to Enhance Stability

PURPOSE: To report the results of a new technique for intraocular lens scleral fixation of temporary haptic externalization and four-point fixation for enhanced stability. METHODS: Two 10–0 polypropylene strands were fixed at two points 2 mm apart on each haptic of a conventional three-piece intraocular lens, using our previously reported method of temporary haptic externalization after injector implantation. Postoperative refractive outcome and stability were evaluated. RESULTS: Although the intraocular lens was fixed at a total of four points, no intraoperative difficulties were observed during the process. Patients showed successful fixation of the intraocular lens postoperatively. The fixed intraocular lens showed good centering and minimal tilting. When compared to the two-point fixation technique, postoperative astigmatism was significantly smaller in the four-point fixation group (1.80 ± 0.84 vs. 1.00 ± 0.0.50, p = 0.033). Lens-induced astigmatism calculated from subtraction of corneal astigmatism from total astigmatism was also significantly smaller in the four-point fixation group (2.23 ± 0.98 vs.1.17 ± 0.0.70, p = 0.043). No postoperative complications were identified during a mean follow-up period of 14.8 months (range, 10 to 19 months). CONCLUSIONS: By fixing the intraocular lens at two points on each side of the haptics, this method minimizes the tilting of the intraocular lens and thus decreases postoperative lens-induced astigmatism. Also, the possibility of intraocular lens dislocation in the long term might be decreased by this two-point fixation technique.

The Correlation between Angle Kappa and Ocular Biometry in Koreans

PURPOSE: To investigate normative angle kappa data and to examine whether correlations exist between angle kappa and ocular biometric measurements (e.g., refractive error, axial length) and demographic features in Koreans. METHODS: Data from 436 eyes (213 males and 223 females) were analyzed in this study. The angle kappa was measured using Orbscan II. We used ocular biometric measurements, including refractive spherical equivalent, interpupillary distance and axial length, to investigate the correlations between angle kappa and ocular biometry. The IOL Master ver. 5.02 was used to obtain axial length. RESULTS: The mean patient age was 57.5 +/- 12.0 years in males and 59.4 +/- 12.4 years in females (p = 0.11). Angle kappa averaged 4.70 +/- 2.70 degrees in men and 4.89 +/- 2.14 degrees in women (p = 0.48). Axial length and spherical equivalent were correlated with angle kappa (r = -0.342 and r = 0.197, respectively). The correlation between axial length and spherical equivalent had a negative correlation (r = -0.540, p < 0.001). CONCLUSIONS: Angle kappa increased with spherical equivalent and age. Thus, careful manipulation should be considered in older and hyperopic patients when planning refractive or strabismus surgery.