Abstract
BACKGROUND: A major focus of toric intraocular lens (IOL) implantation is the rotational stability, especially in the patients with long axial length (AL). In this study, we aimed to evaluate the clinical outcomes after implantation of TECNIS toric IOL in eyes with long AL and identify factors influencing their early-stage stability with preoperative corneal astigmatism. METHODS: The study population consisted of 64 eyes from 52 cataract patients, and these patients had preoperative corneal astigmatism between 1.0 and 3.7 diopters (D) and underwent phacoemulsification and TECNIS toric IOL implantation. Ophthalmic biological measurements were carried out preoperatively, including AL, anterior chamber depth (ACD), lens thickness (LT), vitreous length (VL), anterior chamber volume (ACV), sulcus-to-sulcus (STS) and keratometric value (K). Clinical examinations, including visual acuity, manifest refraction, keratometry, digital anterior segment photographs with pupillary dilation, were performed at 1 and 3 months after surgery. RESULTS: The mean best corrected distance visual acuity (BCDVA) was improved from 0.93 ± 0.35 logarithms of the minimal angle of resolution (logMAR) preoperatively to 0.07 ± 0.10 logMAR postoperatively at 3 months after surgery. The mean residual astigmatism (RAS) was 0.91 ± 0.74D at 3 months, which was significantly decreased compared with the preoperative corneal astigmatism of 1.71 ± 0.55 D. The mean absolute rotation of TECNIS toric IOL at 1 and 3 months was 7.42 ± 11.32 degree (°) (0-79°) and 7.48 ± 11.19°(0-79°), respectively. The mean area of capsulorhexis and the overlapped area between capsulorhexis and IOL optic intraoperatively was 21.04 ± 3.30 mm(2) and 7.40 ± 2.87 mm(2).A positive correlation was found between IOL rotation and the area of capsulorhexis (p = 0.017) at 3 months after surgery. No correlation was found between IOL rotation and AL (p = 0.876), ACD (p = 0.387), LT (p = 0.523), VL (p = 0.546), ACV (p = 0.480), STS (p = 0.884), K1 (p = 0.429), K2 (p = 0.644), average of K1 and K2 (p = 0.520), intraoperative IOL axial direction (p = 0.396), preoperative corneal astigmatism (p = 0.269) or the overlapped area between capsulorhexis and IOL optic intraoperatively (p = 0.131) . CONCLUSIONS: The large CCC was a risk factor for toric IOL rotation. An appropriately smaller sized CCC was conducive to increase the rotational stability of TECNIS toric IOL implantation in cataract cases with long AL.