Long-term evolution of astigmatism following planned extracapsular cataract extraction.

Sixty-six eyes of 66 patients undergoing planned extracapsular cataract extraction with interrupted 10-0 nylon suture wound closure were followed up prospectively for three years following surgery to evaluate the long-term evolution of postoperative astigmatism. The study examined the period beginning three months postoperatively, well after all suture cutting was completed, a point often considered to represent "final postoperative astigmatism." For the group as a whole, the induced astigmatism measured at three months was not stable, but gradually shifted 0.69 diopter toward against-the-rule astigmatism. Three specific patterns of evolution of postoperative astigmatism were identified, depending on the amount of induced astigmatism found at three months. The data revealed that it was not possible to consistently induce with-the-rule astigmatism, although permanent against-the-rule induced astigmatism could be produced. The long-term evolution of postoperative cataract wounds toward more against-the-rule astigmatism seen in this study was not affected by the number of intact nylon sutures. Proper evaluation of any technique to modify postoperative astigmatism must consider the long-term evolution of the cataract wound.

Adjustment sensitivity of horizontal rectus muscles in adjustable strabismus surgery.

A "marking suture" was used in 12 consecutive cases of adjustable strabismus surgery to determine the relationship between ocular alignment and the amount of horizontal muscle adjustment. The average change in ocular alignment was 2.55 prism diopters for each millimeter of muscle adjustment. Regression analysis revealed the relationship to be linear over the range of adjustments studied. The sensitivity of adjustment was the same whether the adjusted muscle was advanced or further recessed and whether the adjusted muscle was the medial rectus or the lateral rectus. No relationship was found between the distance of a recessed muscle from its normal insertion and the subsequent adjustment sensitivity of that muscle. This information, when used clinically in conjunction with a marking suture, can facilitate the adjustment phase of adjustable strabismus surgery.

Use of Healon in eye muscle surgery with adjustable sutures.

Adhesions between the contacting surfaces of conjunctiva, Tenon's capsule, and muscle produce "tissue drag" which can complicate procedures with adjustable muscle sutures. The use of Healon is recommended to minimize this tissue drag and facilitate the "adjustment phase" of muscle surgery with adjustable muscle sutures. Data on 14 consecutive cases demonstrate the utility of Healon in adjustable strabismus surgery.

Night blindness after jejunoileal bypass surgery.

A 53-year-old woman developed night blindness 9 years after jejunoileal bypass surgery. Abnormal rod function was confirmed by dark-adapted electroretinography, and vitamin A deficiency was confirmed by low serum levels of vitamin A and carotene. Administration of oral vitamin A supplementation resulted in complete resolution of the patient's symptom and return of the electroretinogram to normal. Based on this case and the four previously reported cases, we suggest that jejunoileal bypass patients be routinely questioned about decreased night vision. Patients with this complaint should undergo thorough ophthalmic evaluation. Dark-adapted electroretinography or dark adaptation testing should be done to establish the presence of abnormal rod function, and serum levels of vitamin A or carotene should be obtained to identify the cause. It is important to identify vitamin A-deficient patients because of their potential to develop permanent impairment of night vision.

Marked intraocular pressure rise following Nd:YAG laser capsulotomy.

A Nd:YAG laser was used to perform a posterior capsulotomy on a patient one and a half years after phacoemulsification. Within 24 hours the intraocular pressure had increased to 67 mm Hg despite pre-treatment with timolol and acetazolamide. Intraocular pressure eventually returned to pre-capsulotomy levels after several days. A mechanism is postulated for the particularly high pressures encountered in this case.

Lash excision in trichiasis.

A simple technique for lash excision in the surgical management of trichiasis is described. Of 13 patients treated with this technique, 11 had complete relief of symptoms and 2 had significant improvement in symptoms with the remaining symptoms attributable to other manifestations of their underlying disease. There were no complications in any of the cases from the surgical procedure itself. This procedure is quickly and easily performed and has been found to be particularly useful in elderly and debilitated patients, and in those patients whose trichiasis is associated with conjunctival scarring.