The anterior corneal asphericity (Q) with the tangential radius is calculated, and a three-dimensional (3-D) anterior corneal model is constructed. Tangential power maps from Orbscan II are acquired for 66 young adult subjects. The Q-value of each semimeridian in the near-horizontal region is calculated with the tangential radius. Polynomial fitting is used to model the 360-semimeridional varia...

To evaluate the change in the anterior corneal asphericity (ΔQ) comprehensively calculated using the tangential radius (rt ) after LASIK. Forty-two right eyes were evaluated using the Orbscan II corneal topographer. The pre- and postoperative Q-values of the flat principal semimeridians calculated by the sagittal radius were compared to those by the tangential radius. The Q-value of each semime...

PURPOSE To identify proteins differentially expressed between the tear film of keratoconus (KC) patients and control subjects using two dimensional electrophoresis (2-DE) and mass spectrometry-based techniques. METHODS Twenty two patients (44 eyes) diagnosed with bilateral KC and 22 control subjects (44 eyes) were studied in a prospective case-control study. Keratoconus screening programs and...

PURPOSE To investigate normative angle kappa data and to examine whether correlations exist between angle kappa and ocular biometric measurements (e.g., refractive error, axial length) and demographic features in Koreans. METHODS Data from 436 eyes (213 males and 223 females) were analyzed in this study. The angle kappa was measured using Orbscan II. We used ocular biometric measurements, inc...

BACKGROUND The improved detection limit and precision in new-generation commercial assays for cardiac troponin I (cTnI) have lowered the 99th-percentile cutoff value, yielding higher frequencies of positive test results. Because serial testing is important in interpreting low concentrations, we evaluated the biological variation of cTnI in both the short (hours) and long (weeks) terms and deter...

The aim of this study was to evaluate the long-term safety and efficacy of photorefractive keratectomy (PRK) for patients with myopia and thin corneas. In this retrospective case series, we included 74 eyes of 38 patients with myopia and central corneal thickness (CCT) < 550 µm who underwent PRK and had a mean postoperative follow-up period of four years. The following factors were evaluated: C...