Acute angle-closure glaucoma despite previous Nd:YAG laser iridotomy: a report on 13 cases

Background: Nd:YAG laser iridotomy is routinely used as a procedure for primary acute angle-closure glaucoma (AACG). The clear advantage of Nd:YAG laser iridotomy is to resolve pupillary block without opening the eye. Nevertheless it remains unclear whether Nd:YAG laser iridotomy is equally effective as surgical iridectomy. In this context cases in which AACG recurred despite patent Nd:YAG laser iridotomy are of interest.

Methods: In a retrospective study, we analyzed the charts of 90 patients who presented with unilateral primary AACG in our department over 3 years and were treated with a surgical iridectomy. Surgical iridectomy at the 12 o'clock position was performed using a self-sealing corneal incision.

Results: Of the 90 patients with primary AACG, 13 (14.4%) had already been treated with Nd:YAG laser iridotomy. Despite the laser iridotomy, these eyes developed recurrent AACG. The presenting intraocular pressure (IOP) of these 13 eyes was 49.07+/-12.65 mmHg. In 4 eyes, continuous medical glaucoma therapy was used prior to AACG, 8 eyes showed signs of glaucoma damage at the optic disk or/and the visual field. In 2 eyes, the presenting high IOP at AACG could be lowered by medication. All other eyes were operated at high IOP. The average interval between the Nd:YAG laser iridotomy and the AACG was 24.5 weeks. After surgical iridectomy, the IOP was reduced to 12.69+/-4.11 mmHg and was 16.62+/-3.86 mmHg at the end of the observation period.

Conclusions: In spite of Nd:YAG laser iridotomy recurrent AACG can occur. Surgical iridectomy is capable of permanently resolving the pupillar block in these cases.