Hyuk Jin Choi

PURPOSE. To solve the shortage of donor corneas, a decellularizing method based on hypertonic saline treatment was introduced, and a favorable outcome was observed in pig-to-rabbit lamellar corneal transplantation. This study was an investigation of the efficacy of pig-to-nonhuman primate lamellar corneal transplantation, using both decellularized and fresh porcine corneas to assess feasibility as a substitute for human corneas. METHODS. Nine Chinese rhesus macaques underwent lamellar corneal tr

PURPOSE: To investigate and validate methods for measuring the radius of anterior scleral curvature using anterior segment optical coherence tomography images. METHODS: Twenty-four volunteers were enrolled in this study. Anterior segment optical coherence tomography images, centered on horizontal/vertical limbus, including adjacent anterior sclera, were obtained in addition to conventional images centered on the optical axis. Central horizontal, nasal, and temporal optical coherence tomography i

We propose a post-processing method in the wavelet transform domain that can significantly reduce the blocking effects in low-bit-rate block-transform-coded images. Although the quantization noise of the transform coefficients is the sole source of error in a coded image, the properties of block transform make the errors appear in two categories: blocky noise, which causes blocking effects, and granular (nonblocky) noise. Noting that subband coding does not suffer from blocky noise, the proposed

BACKGROUND: It has been reported that hyperacute rejection (HAR) does not occur after pig-to-nonhuman corneal xenotransplantation. However, considering that immune privilege is already disrupted in most human corneal recipients, and the expression of αGal can be gradually reduced after pig-to-rat corneal transplantation, the long-term survival of corneal grafts from wild-type pigs cannot be guaranteed. Accordingly, we aimed to investigate the effect of αGal on the change in anti-Gal antibodies,

The purpose of this study is to investigate cross-reactivity between hypertonic saline-treated decellularized porcine corneal lamellae for corneal xenobridging and subsequent corneal allotransplants. Five Chinese rhesus macaques, which had undergone anterior partial thickness corneal transplantation using hypertonic saline-treated decellularized porcine corneal lamellae in preceding experiments, were used as recipients for subsequent full-thickness corneal allografts. To determine whether sensit

To report the efficacy and safety of large diameter scleral lenses and determine their suitability in Asian subjects with intractable ocular surface diseases. This prospective study enrolled intractable ocular surface diseases subjects with uncorrected visual acuity > counting finger but ≥ 0.3 logMAR and best-corrected visual acuity (BCVA) ≥ 0.3 logMAR, to fit large diameter scleral lenses for 12 weeks. 21 eyes (13 subjects) consisting ten eyes (47.6%) with persistent epithelial defects, 6 (28.6

BACKGROUND: The risk of xenozoonosis mainly by porcine endogenous retrovirus (PERV) has been considered as one of the main hurdles in xenotransplantation and therefore should be elucidated prior to the clinical use of porcine corneal grafts. Accordingly, an investigation was performed to analyze the infectivity of PERVs from porcine keratocytes to human cells, and the long-term risk of transmission of PERVs was determined using pig-to-non-human primate (NHP) corneal transplantation models. METHO

CCT is a significant factor in predicting the extent of localized RNFL defect at the initial examination of NTG patients.

Pterygium is an abnormal growth of fibrous conjunctival tissue that invades the cornea, resulting in corneal distortion, astigmatism, and increased higher-order aberrations (HOAs). However, few studies have compared eyes with pterygium to normal fellow eyes when interpreting HOAs and there is no study that revealed the effect of the thickness or grading of the pterygium on the change of HOAs. Therefore, we evaluated the effects of nasal pterygium by comparing the normal fellow eye of 59 patients

BACKGROUND: Xenotransplantation using fresh porcine corneas has been suggested as a feasible alternative to overcome the shortage of human donor corneas. Successful long-term survival of grafts without evidence of xenozoonosis in clinically applicable pig-to-non-human primate corneal transplantation model has brought researchers close to human clinical trials. Accordingly, we aimed to prepare a clinical trial protocol to conduct the first corneal xenotransplantation. METHODS: We developed the cl

Glaucoma screening can be helpful for early detection of glaucoma. However, improvement of the screening strategy is needed in order to enhance its specificity for glaucoma.

An 18 year old male who had been taking vigabatrin for complex partial seizure was referred for visual field testing. The cumulative vigabatrin dose was about 6.0 kg over the seven and a half year period. There were bilateral symmetric visual field constrictions with greater loss of the nasal field (fig 1). On the retinal nerve fibre layer (RNFL) photographs discernible RNFL losses in the peripheral retina with a relative preservation of papillomacular bundles were observed bilaterally (fig 2).