J Korean Ophthalmol Soc.  2010 Nov;51(11):1479-1484. 10.3341/jkos.2010.51.11.1479.

Changes in Anterior Segment Biometry by Laser Iridotomy in Eye With Shallow Anterior Chamber

• Yeom DJ
• Lee JH

• KMID: 2213974
• DOI: http://doi.org/10.3341/jkos.2010.51.11.1479

Abstract

PURPOSE
To identify the impact of the presence of peripheral anterior synechia (PAS) on the depth of the anterior segment in patients with a shallow anterior chamber after laser iridotomy (LI) by analyzing changes in the anterior segment biometry using ultrasound biomicroscopy (UBM).
METHODS
Twenty eyes of 20 patients with PAS and shallow anterior chamber, and another 20 eyes of 20 patients with shallow anterior chamber without PAS were studied. The changes in the anterior segment biometry for each group of patients were examined using gonioscopy and UBM before and after the LI.
RESULTS
The central corneal thicknesses and scleral thicknesses of the two groups did not show significant differences (p > 0.05). The anterior chamber depths, anterior chamber angles, trabecular meshwork-iris distances, and angle-opening distances 500 increased significantly after the peripheral LI (p < 0.05) in both groups. However, the difference in the increases in the anterior segment biometries between the two groups was not statistically significant.
CONCLUSIONS
LI can increase the depth of the anterior chamber regardless of the presence of PAS.

Keyword

Anterior segment biometry; Laser iridotomy; Peripheral anterior synechia; Ultrasound biomicroscopy

MeSH Terms

Anterior Chamber
Biometry
Eye
Gonioscopy
Humans
Microscopy, Acoustic

Figure

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  Figure 1. UBM images of the temporal angle of eyes before and after LI in PAS-positive eye and PAS-negative eye that show flattening of the iris and widening of the angle in detail. (A) Before LI in PAS-negative eye. (B) After LI in PAS-negative eye. (C) Before LI in PAS-positive eye. (D) After LI in PAS-positive eye.

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