advertisement
Abstract #6269 Published in IGR 2-2
Endoscopic goniotomy with the free electron laser in congenital glaucoma rabbits
Sun W; Shen JH; Shetlar DJ; Joos KMJournal of Glaucoma 2000; 9: 325-333
PURPOSE: Goniotomy is a surgical treatment of choice to treat primary infantile glaucoma. Goniotomy has been studied in vitro in animal and human cadaver eyes with several lasers. The objective of this study was to investigate the functional and morphological effectiveness of goniotomy with the free electron laser in comparison with conventional needle goniotomy in early congenital glaucoma rabbits. MATERIAL AND METHODS: Ten rabbits with early congenital glaucoma underwent goniotomy over 100-120° with a needle or the free electron layer. The wavelength was 6.45 μm and the energy level ranged from 2.2-3.5 mJ at 30 Hz. Because most corneas were edematous in these rabbits, an Olympus 0.8-mm diameter endoscope was coupled to the laser waveguide or the needle and inserted into the anterior chamber filled with a viscoelastic material to perform the goniotomy. Intraocular pressures (IOPs) were followed for up to three weeks before an acute goniotomy was performed in the contralateral eye. All eye specimens were processed for light microscopic evaluation. RESULTS: Incision of the pectinate ligaments and underlying trabecular meshwork was visualized through the endoscope on a video monitor during the surgeries. the mean IOP decreased after free electron laser goniotomy and after needle goniotomy, and the edematous corneas became clear in some cases. Histological study showed successful lysing of the pectinate ligaments by the free electron laser, with no obvious collateral thermal damage. However, some areas of peripheral anterior synechiae occurred. Similar results were observed in needle goniotomy cases. CONCLUSIONS: The free electron laser is capable of performing goniotomy in rabbit eyes with lower IOPs in treated eyes three weeks after surgery. The histological results of free electron laser goniotomy are comparable to those of conventional goniotomy. The endoscope provides beneficial visualization to perform the goniotomy in eyes with edematous corneas. The rabbit with early congenital glaucoma is also a useful infantile glaucoma surgical model.
Dr. K.M. Joos, Vanderbilt University, 1215 21st Avenue South, 8017 MCF, Nashville, TN 37232-8808, USA
Classification:
12.9 Trabeculotomy, goniotomy (Part of: 12 Surgical treatment)
