Microvascular change of the anterior eye segment after tenotomy in the rabbit

Background: The microvascular changes secondary to anterior segment ischemia following tenotomy of the extraocular muscles have not been studied in the rabbit. Methods: Using scanning electron microscopy of methylmethacrylate ocular microvascular luminal castings, the anterior eye segment vasculature after tenotomy was documented and compared to that after occlusion of the bilateral long posterior ciliary arteries and that in the eyes that were not subjected to any surgical intervention. Results: Five days and 1 week after the surgical intervention with tenotomy, microvascular change secondary to the anterior segment ischemia was not apparent, but 2 weeks after the tenotomy subtle evidence of ischemia such as new vessels in the iris was observed. Seven weeks after tenotomy, marked microvascular change was observed where corneal new vessels arose from the superior perilimbal arteries. In contrast, we found prominent microvascular changes 2 weeks after the occlusion of the long posterior ciliary arteries. Conclusions: Tenotomy of the rabbit eye causes microvascular change similar to that in occlusion of the long posterior ciliary arteries. This result suggests that the anterior ciliary artery of the rabbit contributes blood flow to the anterior eye segment and also has a stronger connection with the long posterior ciliary artery than previously reported.