Purpose: To evaluate the ultrasound biomicroscopic appearance of the anterior segment before and after cataract extraction in eyes with plateau iris syndrome and to determine the effect of postoperative zonular relaxation on ciliary body position.
Design: Interventional case series.
Methods: Eyes with plateau iris syndrome scanned before and after cataract extraction between January 1994 and September 2001 were enrolled. The iridociliary relationship and the anterior chamber depth at a distance of 3 mm from the scleral spur were assessed.
Results: We examined six eyes of six patients. Mean patient age was 74.2 +/- 6.4 years (standard deviation [SD]) (range, 65-81 years). Mean refractive error was + 1.0 +/- 3.9 diopters [D] (range, -5.75-+5.50), and mean axial length was 21.85 +/- 0.77 mm (range, 20.90-22.95 mm). All eyes had undergone laser iridotomy and argon laser peripheral iridoplasty before cataract extraction. Ultrasound biomicroscopy examination revealed a narrow angle and absence of a ciliary body sulcus in all eyes with focal areas of iridotrabecular apposition in three eyes. Following cataract extraction, the anterior chamber depth increased (P =.0006, paired t test), while the iridociliary contact remained unchanged.
Conclusions: Iridociliary apposition persists after cataract extraction in plateau iris syndrome. Whether the cause is congenital or acquired, or both, remains to be determined.