Evaluation of long-term clinical outcomes after toric implantable collamer lens implantation.

PURPOSE: To evaluate the long-term (8-10 years) outcomes of toric implantable collamer lens (TICL) surgery. SETTING: Nagoya Eye Clinic, Nagoya, Aichi, Japan. DESIGN: Retrospective observational study. METHODS: Patients who underwent TICL surgery from 2005 to 2009 to correct myopia and myopic astigmatism were enrolled. The safety, efficacy, predictability, astigmatism correction efficacy, and complications were evaluated using preoperative, 1-year postoperative, and final examination data. RESULTS: 133 eyes of 77 patients were included. At the final visit, the mean uncorrected and corrected visual acuities were -0.01 ± 0.2 and -0.17 ± 0.05, respectively. The mean safety and efficacy indices were 0.91 ± 0.26 and 0.68 ± 0.21, respectively. The manifest astigmatism was -0.45 ± 0.43 diopters (D). The mean corneal astigmatism change from 1 year postoperatively to the final visit was 0.40 ± 0.26 D. Of the 38 eyes with a change in corneal astigmatism ≥0.5 D, 30 eyes (78.9%) changed to against-the-rule (ATR) astigmatism, 1 (2.6%) changed to oblique astigmatism, and 7 (18.4%) changed to with-the-rule (WTR) astigmatism. The mean manifest astigmatism change from 1 year postoperatively to the final visit was 0.43 ± 0.52 D. Of the 60 eyes with a change in manifest astigmatism ≥0.5 D, 25 (41.7%) changed to ATR astigmatism, 18 (30.0%) changed to oblique astigmatism, and 17 (28.3%) changed to WTR astigmatism. During follow-up, 8 (6.0%) of 133 eyes developed anterior subcapsular cataracts, among which 4 (3.0%) underwent TICL removal and phacoemulsification and aspiration. No vision-threatening complications occurred. CONCLUSIONS: TICL surgery showed good long-term astigmatism-correcting effects, although the long-term uncorrected visual acuity decreased. The procedure was effective in correcting myopia and astigmatism.

Evaluation of CorvisST biomechanical parameters and anterior segment optical coherence tomography for diagnosing forme fruste keratoconus.

PURPOSE: To investigate the utility of biomechanical property measurements using a Scheimpflug-based tonometer (SBT) and/or anterior segment optical coherence tomography (AS-OCT) for diagnosing forme fruste keratoconus (FFK). METHODS: In this retrospective interventional case series, 23 eyes with FFK of 23 consecutive patients and 52 eyes of 52 healthy volunteers who visited our keratoconus outpatient clinic were enrolled. Logistic regression analysis was conducted to determine the causal relationship between FFK diagnosis and each parameter. RESULTS: When only SBT was used, the corneal stiffness parameter, stiffness parameter A1 (SP-A1) and the corneal velocity at first applanation were selected as explanatory variables, and sensitivity, specificity and area under the receiver operating characteristic curve (AUROC) were 82.9%, 86.9% and 0.938, respectively. When only AS-OCT parameters were used, the posterior corneal asymmetric component and central corneal thickness were selected, and the sensitivity, specificity and AUROC were 82.6%, 94.2% and 0.893, respectively. When parameters from both methods were used, SP-A1 and the posterior corneal asymmetry component derived from Fourier analysis were selected as explanatory variables, and sensitivity, specificity and AUROC were 91.30%, 90.38% and 0.947, respectively. No significant differences in AUROC were observed between diagnoses using each device and the combination of both devices (AS-OCT versus SBT, p = 0.314; integrated parameters versus AS-OCT, p = 0.081; integrated parameters versus SBT, p = 0.234). CONCLUSION: Optimization of SBT and AS-OCT parameters allowed for the diagnosis of FFK at a clinically usable level. Forme fruste keratoconus (FFK) diagnosis integrating biomechanical properties with AS-OCT showed no superiority compared to diagnosis based on a single device.