Visual Outcomes, Footplate Position and Vault Achieved with the Visian Implantable Collamer Lens for Myopic Astigmatism

Purpose. To assess the efficacy, safety, and predictability of the Visian Implantable Collamer Lens (ICL) model having a central port in patients over 40 years of age. Methods. This study included 33 eyes from 21 patients who underwent V4c ICL implantation for the correction of myopia and myopic astigmatism. We assessed uncorrected (UDVA) and corrected (CDVA) distance visual acuity, refraction, intraocular pressure (IOP), endothelial cell density (ECD), vault, and adverse events occurring over a 1-year period. Results. Mean age of the patients at the time of implantation was 43.52 ± 4.49 years (range: 40 to 56 years). Efficacy and safety indexes were 1 and 1.09, respectively. Surgical outcomes for CDVA were as follows: no eye lost any lines, 19 eyes (57.58%) showed no CDVA changes, 7 eyes (21.21%) gained 1 line, 4 eyes (12.12%) gained 2 lines, and 3 eyes (9.09%) gained ≥3 lines. Mean postoperative spherical equivalent (SE) was −0.09 ± 0.47 D. A total of 29 eyes (87.8%) were within ±0.50 D and 31 eyes (93.9%) were within ±1.00 D of the desired SE. At 1-year, mean IOP was 15.27 ± 3.03 mmHg (range: 9 to 20 mmHg, p=0.12 pre vs. post) and mean ECD was 2516 ± 234 cells/mm2 (p=0.29 pre vs. post). Mean postoperative vault was 320 ± 136 μm, with 201–300 μm being the most prevalent vault range for 9 eyes (31.03%). None of the eyes showed a vault >701 μm. There were neither intraoperative nor postoperative complications; in fact, all ICL implantation procedures were uneventful. Conclusions. Our study’s findings support the use of this lens in patients over 40 years of age. A long follow-up period is advisable to monitor ICL position relative to the crystalline lens.

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Vector analysis of small incision lenticule extraction and toric implantable collamer lens implantation for astigmatism correction

European Journal of Ophthalmology ◽

10.1177/1120672120930607 ◽

2020 ◽

pp. 112067212093060

Author(s):

Ting Wan ◽

Houfa Yin ◽

Zhiyi Wu ◽

Yabo Yang

Keyword(s):

Vector Analysis ◽

Small Incision Lenticule Extraction ◽

Implantable Collamer Lens ◽

Small Incision ◽

Astigmatism Correction ◽

Induced Astigmatism ◽

Lenticule Extraction ◽

The Difference ◽

Surgically Induced ◽

Myopic Astigmatism

Objectives: To compare the efficacy of small incision lenticule extraction (SMILE) and toric implantable collamer lens (TICL) implantation for myopic astigmatism correction using vector analysis. Methods: In this retrospective study, 171 eyes of 171 patients with cylinder ⩾1.0 diopters (D) were recruited, with 97 eyes underwent SMILE and 74 eyes underwent TICL implantation. Preoperative and 3-months postoperative visual and refractive results were examined. The astigmatism correction, graded by the degree of preoperative cylinder was compared between two groups using vector analysis. Results: At 3-months postoperatively, the residual cylinder was −0.10 ± 0.21 D in the SMILE group and −0.30 ± 0.32 D in the TCL group ( p < 0.05). Furthermore, 98% and 85% of eyes had the cylinder within ±0.5 D in the SMILE and TICL group, respectively. The vector analysis revealed similar target induced astigmatism vector in two groups. However, the difference vector, magnitude of error, angle of error, and index of success were significantly higher (0.30 ± 0.32 D, −0.19 ± 0.25, −2° ± 4.35°, and 0.16 ± 0.17 D, respectively) in the TICL group than the values in the SMILE group (0.10 ± 0.21 D, −0.05 ± 0.20, −0.03° ± 2.13°, and 0.05 ± 0.12, respectively), regardless of the degree of preoperative cylinder (all p < 0.05). For preoperative cylinder < 2.0 D, surgically induced astigmatism vector and correction index in the SMILE group were higher than those in the TICL group ( p < 0.05). Conclusion: Both SMILE and TICL implantation are effective techniques for myopic astigmatism correction. However, the accuracy of correction in the magnitude and axis of astigmatism with SMILE was better than that achieved with TICL implantation.

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