OBJECTIVE: To explore the postmortem changes of cornea thickness measured by ultrasonic pachymetry. METHODS: Eleven rabbits were randomly divided into two groups: one group with intact corneal epithelium and another group without intact corneal epithelium. In the later group, the corneal epithelium of the rabbit was scraped using mechanical elimination method. The corneal thickness was monitored continuously by ultrasonic pachymetry at several postmortem interval points in rabbits of the two groups. The changes of corneal thickness and postmortem interval were explored by relative regression analysis. RESULTS: The thickness of the cornea showed a strong non-linear correlation with the postmortem interval in the group with intact corneal epithelium. The group with intact corneal epithelium showed the correlation coefficient 0.922 and the group without intact corneal epithelium showed the correlation coefficient 0.822, respectively. CONCLUSION The corneal thickness measured by ultrasonic pachymetry shows a potential value for estimating early postmortem interval. The intact corneal epithelium is a crucial factor for the measurement of cornea thickness by ultrasonic pachymetry.
Animals ; Cornea/pathology* ; Corneal Topography/methods* ; Epithelium, Corneal/ultrastructure* ; Female ; Forensic Pathology/methods* ; Male ; Postmortem Changes ; Rabbits ; Regression Analysis ; Reproducibility of Results ; Time Factors ; Ultrasonography

The purpose of this study is to characterize and compare the ultrastructural changes occurring during the in vivo cultivation of corneal epithelium on amniotic membrane (AM) at several different time points. Corneal burn patients (n=7) with a corneal epithelial defect and severe limbal damage were selected. Initially, AM transplantation with limbal autograft was performed at the acute stage of corneal burn to reconstruct the damaged ocular surface. One to six (mean interval; 3.3+/-1.2) months later, the central part of AM containing an in vivo expanded corneal epithelium was excised and retransplanted in adjacent lesions. The excised epithelium with AM was examined by electron microscopy and immunohistochemical study. By electron microscopy, one and two months after expansion, cultivated epithelium on AM showed an undifferentiated epithelium and an incomplete basement membrane (BM). But, after three months, the cultivated epithelium began to differentiate into a multilayered epithelium with a continuous BM with increased hemidesmosomes. These findings were further confirmed by immunohistochemical study, that cytokeratin K3 was expressed in the cultivated corneal epithelium and newly formed BM was partially positive of collagen IV at three months. At least 3 months may be needed for the proliferation and differentiation of in vivo cultivated corneal epithelium on AM.
Stem Cells/cytology ; Stem Cell Transplantation/*methods ; Middle Aged ; Microscopy, Electron ; Male ; Keratin-3/biosynthesis ; Immunohistochemistry ; Humans ; Epithelium, Corneal/cytology/*metabolism/*pathology/*transplantation ; Corneal Diseases/*therapy ; Burns/*surgery/therapy ; Biological Dressings ; Amnion/*ultrastructure ; Adult

This study investigated the toxicity of commercial non-steroid anti-inflammatory drug (NSAID) eye solutions against corneal epithelial cells in vitro. The biologic effects of 1/100-, 1/50-, and 1/10-diluted bromfenac sodium, pranoprofen, diclofenac sodium, and the fluorometholone on corneal epithelial cells were evaluated after 1-, 4-, 12-, and 24-hr of exposure compared to corneal epithelial cell treated with balanced salt solution as control. Cellular metabolic activity, cellular damage, and morphology were assessed. Corneal epithelial cell migration was quantified by the scratch-wound assay. Compared to bromfenac and pranoprofen, the cellular metabolic activity of diclofenac and fluorometholone significantly decreased after 12-hr exposure, which was maintained for 24-hr compared to control. Especially, at 1/10-diluted eye solution for 24-hr exposure, the LDH titers of fluorometholone and diclofenac sodium markedly increased more than those of bromfenac and pranoprofen. In diclofenac sodium, the Na+ concentration was lower and amount of preservatives was higher than other NSAIDs eye solutions tested. However, the K+ and Cl- concentration, pH, and osmolarity were similar for all NSAIDs eye solutions. Bromfenac and pranoprofen significantly promoted cell migration, and restored wound gap after 48-hr exposure, compared with that of diclofenac or fluorometholone. At 1/50-diluted eye solution for 48-hr exposure, the corneal epithelial cellular morphology of diclofenac and fluorometholone induced more damage than that of bromfenac or pranoprofen. Overall, the corneal epithelial cells in bromfenac and pranoprofen NSAID eye solutions are less damaged compared to those in diclofenac, included fluorometholone as steroid eye solution.
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage/*toxicity ; Benzophenones/administration & dosage/toxicity ; Benzopyrans/administration & dosage/toxicity ; Bromobenzenes/administration & dosage/toxicity ; Cell Movement/drug effects ; Cells, Cultured ; Diclofenac/administration & dosage/toxicity ; Epithelial Cells/drug effects/metabolism/ultrastructure ; Epithelium, Corneal/cytology/*drug effects/metabolism ; Fluorometholone/administration & dosage/toxicity ; Humans ; L-Lactate Dehydrogenase/metabolism ; Microscopy, Electron, Transmission ; Ophthalmic Solutions ; Propionates/administration & dosage/toxicity