Ultrasound biomicroscopic changes after laser iridotomy or trabeculectomy in angle-closure glaucoma.

Compared with normal eyes, eyes with primary angle-closure glaucoma (PACG) show an increased lens thickness and a more anteriorly situated lens, the latter of which may be associated with anteriorly situated ciliary process.1-4 Relative pupillary block and iris crowding are involved in the development of angle closure in PACG. Ultrasound biomicroscopy (UBM) is usually able to determine the mechanism of elevated intraocular pressure (IOP) by showing the relationship between the peripheral iris and the trabecular meshwork. In our previous study of PACG by UBM, we demonstrated that there are two types of appositional angle-closure glaucoma (ACG) (types B and S) and showed the forward rotation of the ciliary process without changing the ciliary process-iris angle (CPI).1 As for the release of pupillary block of the eye or preventing the fellow eye from an acute glaucomatous attack, laser iridotomy (LI) can be tried. LI relieves the pupillary block and opens the angle of the anterior chamber. For the eyes of uncontrolled IOP by glaucoma medications and LI, we performed primary trabeculectomy (PT) or trabeculectomy combined with cataract surgery. Until now, many studies have reported on the configuration of the anterior segment after peripheral LI, but there have Korean J Ophthalmol Vol. 18:9-14, 2004