refractive surgical problem
▪ This is an intriguing case. First, the patient is black and thus would have different scarring behavior than patients of other races. Second, it would be helpful to have a photograph of both eyes and ultrasound pachymetry of the whole cornea. The difference between the central corneal thickness (523 μm) in left eye in July 2003 and that in December 2003 (466 μm) is too high to be acceptable. The increasing astigmatism is related to scarring of the trabeculectomy scleral flap after the use of MMC some time ago.
Furthermore, my attention is drawn to the behavior of the astigmatism in the inferotemporal quadrant. There is a slight corneal protrusion present in the corneal topography (TMS) taken in July 2003. It looks like pellucid marginal degeneration that is slowly increasing and might be influenced by the use of MMC during glaucoma surgery. The position (inferotemporal) and the patient's age are consistent with this. The right eye shows a mild, similar aspect. I would start treatment with a couple of curvilinear relaxing incisions on the steepest meridian. As I am fairly sure this first step would be insufficient, I would move forward with a peripheral sliding keratoplasty in line with the ectatic cornea in the inferotemporal meridian. This procedure can control intraoperative astigmatism and adjust postoperative astigmatism through selective suture removal.© 2004 by Lippincott Williams & Wilkins, Inc.