Betech HM, Baca LO, Velasco R, Levine A, Rodríguez RA, Rosales MML

Language: Spanish
References: 13
Page: 241-245
PDF size: 150.02 Kb.

ABSTRACT

Purpose: To search the microanatomic differences of proximal and distal vessels in corneal neovascularization and correlate them with corneal fluorangiography.
Methods: A descriptive, transversal, observational and prospective study was carried out in the Cornea Department of our Institution, along with the Electron Microscopy Department at the Universidad Nacional Autonoma de Mexico (UNAM), between March 2001 and December 2002. We selected patients for penetrating keratoplasty with corneal neovascularization. Four steps were followed in each cornea: 1. Corneal fluorangiography, 2. Penetrating keratoplasty, 3. Electron microscopy and 4. Result correlation.
Results: Eleven eyes were studied, 8 (73%) eyes with interstitial keratitis, one (9%) with graft rejection, one (9%) with primary graft failure and one (9%) with corneal pannus. Ten eyes showed bulb images (leakage in the distal vessels) in the corneal fluorangiography , and only one did not had leakage patterns (pannus eye). With the electron microscope in the small caliber vessels we observed a higher number of vacuoles, alterations in the zonulae occludens junction between endothelial cells, less number of nuclear pores, discontinuity of the membrane, less filamentary structures (responsible of the cell mobility), less pinocytic vesicles (responsible of substance transportation). In proximal high caliber vessels we observed a more continuous membrane, better filamentary structures, a higher number of nuclear pores and more pinocytic vesicles. These findings were similar in all corneas studied except the cornea with pannus.
Conclusions: Electron microscopy shows evidence of less damage in the vascular wall of high caliber vessels in comparison with the smaller vessels. The vascular wall in high caliber neovessels present similar characteristics to those found in normal vasculature. The presence of nuclear pores may be directly related with a better vascular structure and in consequence less leakage in the fluorangiography in high caliber vessels.

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