Therapeutic effectiveness of toric implantable collamer lens in treating ultrahigh myopic astigmatism

Abstract

With a rapid increase in the prevalence of Ultra-High Myopic Astigmatism (UHMA), especially in the youth, there have been many studies on visual correction. In our study, we investigated the clinical value of the Toric Implantable Collamer Lens (TICL) in UHMA. We conducted a retrospective study between 2011 and 2013. TICL implantation was performed on fifteen UHMA patients (30 eyes), and all these patients were regularly followed up for 12 months. The preoperative and postoperative data, including Uncorrected Visual Acuity (UCVA), Best Corrected Visual Acuity (BCVA), Intraocular Pressure (IOP), and corneal endothelial counts, were all analysed using the paired-sample t-test. The 12-month spherical mirror (SPH) of the surgical eye was -0.25~+0.25 D, and the Cylinder mirror (CYL) was 0~-0.50 D. Twenty patients exhibited an increase in UCVA by one level in comparison to the preoperative BCVA, amounting to a 66.7% increase; 20.0% of patients exhibited an increase in UCVA by two levels. A comparison between the preoperative and postoperative IOP showed no statistically significant difference. No difference was also found in mean corneal endothelial counts before and after the operation. A decrease in visual acuity was observed in one eye at the 3 rd -month of review; this was corrected by TICL position adjustment. Precisely measuring the preoperative parameters, selecting the appropriate TICL, more thoroughly aspirating sodium hyaluronate intraoperatively, and maintaining a stable IOP were important for maintaining the effectiveness, safety and stability of TICL in treating UHMA.