J Korean Ophthalmol Soc.  1974 Jun;15(2):138-144.

Epikeratoprosthesis and the Corneal Swelling After Removal of Its limiting layers

• Kim JH

Abstract

It is well known that the corneal stroma will swell when it is exposed to an aqueous solution or water in vitro, or when the limiting layers are removed in vivo. These in vivo experiments are concerned with the measurement and comparisons of corneal swelling after destruction of either of its layers (epithelium, endothelium and Descemet's membrane) and of reduction of corneal swelling with the application of epikeratoprosthesis (EKP).
MATERIALS AND METHODS
Adult albino rabbits weighing 2-3kg each were used throughout these experiments. To remove the limiting layers, the rabbit was anesthesized with 0.5% pontocaine topical in epithelium removal group and nembutal systemically in another groups, and the epithelium was removed with gauze (Kim et ai, 1971) and the endothelium or/and Descemet's membrane was carefully removed with a specially bent hypodermic needle (Maurice and Giardini, 1951) under the aid of slit-lamp biomicroscope with high magnification. Suspicious cases were confirmed by inspection of sections of the excised cerneal tissues under the microscope after end day of experiments. The changes of corneal thickness were measured with the Mishima-Hedbys modified pachometer which was mounted on Haag Streit 900 slit-lamp. And EKP was made from the material of methylmethacrylate (Kaufman type), and its periphery was painted one mm broad with isobutyl cyanoacrylate as an adhesive.
RESULTS
AND SUMMERY: 1. The mean central corneal thickness of 48 normal rabbit eyes was 0.409mm +/- 0.005(S.E.) 2. The average rate of increase was initially about 0.4% of the thickness per minute for the epithelium, 0.7-0.9% per minute for the endothelium and endothelium plus Descemet's membrane, and 1.2% per minute for the whole layers. 3. After the removal of the epithelium the cornea swelled on the average to one half its thickness until after about 48 hrs and then returned its normal thickness with epithelium regrowth. 4. A significant difference was not found between the endothelium removal and the endothelium plus Descemet's membrane removal groups, and the maximal swelling of these was a little more of double of its original thickness. 5. After the removal of the epithelium, the endothelium and Descemet's membrane the corneal stroma swelled over 3 times of its original thickness after 24 hrs. 6. With the application of EKP on the bared stroma, its swelling could be limited under a double of its original thickness, and EKP treatment produced corneal thickness reductions of approximately 50% in early to about 100% in late in comparing with the whole layers removal group.

MeSH Terms

Adhesives
Adult
Bucrylate
Cornea
Corneal Stroma
Descemet Membrane
Endothelium
Epithelium
Humans
Methylmethacrylate
Needles
Paint
Pentobarbital
Rabbits
Tetracaine
Adhesives
Bucrylate
Methylmethacrylate
Pentobarbital
Tetracaine