A quantitative electron microscopic study of growing corneal lymphatic vessels

Following silver nitrate injury to rabbit corneas, injection of carbon into the corneas showed the presence of new corneal lymphatic vessels in addition to the new corneal blood vessels.Quantitative measurements of several vessel parameters including endothelial thickness, area of vessel and lumen and circumference of vessel and lumen were made using electron micrographs of cross-sections of corneal lymphatic vessels of various ages. The thickness of the endothelium was found to decrease as the vessel matures, whereas both the area and the circumference of both vessel and lumen increase with age. This is in agreement with qualitative observations.Procedures for estimating the accurate age of vessels from their physical dimensions and for assessing the degree of tortuosity of the endothelial surfaces are presented and discussed.