Five-Year Changes in Axial Length After Iris-Fixated Phakic Intraocular Lens Implantation
Narrative Responses:
Purpose
To evaluate retrospectively the axial elongation after implantation of an iris-fixated phakic intraocular lens (pIOL) (Artiflex, Ophtec BV, Groningen, Netherlands) in Japanese eyes, by subtracting the axial length 5 years postoperatively from the preoperative value.
Methods
This study included 16 eyes of eight patients (mean age, 36.1 years) with myopia exceeding -7.5 diopters (D) (spherical equivalent [SE]) treated with Artiflex implantation and followed for more than 5 years postoperatively. Ocular higher order aberrations (HOAs) to the sixth order for a 4-mm pupil diameter were recorded preoperatively and 6 months postoperatively. Multiple regression analysis was performed to identify factors affecting axial elongation, in which the covariates were age, sex, target refraction, preoperative intraocular pressure, keratometry, mesopic pupillary diameter, anterior chamber depth (ACD), axial length, spherical aberration (SA) (Z40), HOAs.
Results
The mean SE changed from -10.94 ± 1.87 (standard deviation) D preoperatively to -0.91 ± 0.29 D 5 years postoperatively. The mean axial length changed from 28.10 ± 1.73 mm preoperatively to 28.13 ± 1.73 mm 5 year postoperatively (P = 0.485); the axial elongation was 0.03 ± 0.17 mm over 5 years. Both parameters were measured using the IOLMaster (Carl Zeiss Meditec, Jena, Germany) phakic mode. Multiple regression analysis showed that only the preoperative ACD was associated with axial elongation (P = 0.012) over 5 years postoperatively (axial elongation = -2.190 + 0.580 × preoperative ACD, R2 = 0.419).
Conclusion
There was no significant difference in the axial length between preoperatively and 5 years postoperatively, and it was consistent with a previous study that reported the long-term refractive stability of the Artiflex pIOL. Our results suggested that the greater the preoperative ACD the more axial elongation occurs after Artiflex implantation.