Purchase this article with an account.
N. S. Calixto, R. V. Mérula, S. Cronemberger, A. Diniz Filho; Comparative Ultrasound Biomicroscopic Study Between the Fellow Eyes of Acute Angle Closure and Primary Open Angle Glaucoma With Narrow Angle. Invest. Ophthalmol. Vis. Sci. 2008;49(13):5098. doi: https://doi.org/.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To compare topologic features between fellow eyes of subjects with unilateral acute primary angle closure (APAC) and eyes of subjects with primary open angle glaucoma with narrow angle (POAGNA), and to identify any characteristics that could contribute to explain the acute episode.
Thirty fellow eyes of subjects with unilateral APAC and 30 eyes of subjects with POAGNA were prospectively examined by ultrasound biomicroscopy (UBM) under light and dark conditions. All eyes presented normal pupillary reaction and were examined before surgical/laser treatment in the superior (SQ) and inferior (IQ) quadrants. UBM parameters such as anterior chamber depth (ACD), angle opening distance at 250 µm/500 µm from the scleral spur (AOD250/AOD500), trabecular ciliary process distance (TCPD), the iris thickness measured along the same line as the TCPD (ID1), the iris thickness 2 mm from the iris root (ID2), the maximum iris thickness near the pupillary edge (ID3) and iris-lens contact distance (ILCD) were measured and compared between the two groups.
Significant differences between APAC fellow and POAGNA eyes under light and dark examinations were found in ACD, P < 0.001; AOD250SQ, P < 0.001; AOD250IQ, P < 0.001; AOD500SQ, P < 0.001; AOD500IQ, P < 0.001; TCPDSQ light, P = 0.010; TCPDSQ dark, P = 0.031; and TCPDIQ light, P = 0.010. The thickness of the iris (ID1, ID2 and ID3) was the same as that in APAC fellow eyes and in POAGNA eyes, both superior and inferior quadrants, except for ID3SQ in dark conditions that showed statistical marginal significance (P = 0.035). Significant differences between light and dark examinations of APAC fellow eyes were found in the ILCDSQ (P = 0.009) and ILCDIQ (P = 0.006), and of POAGNA eyes in the ILCDSQ (P = 0.047) and ILCDIQ (P < 0.001).
The APAC fellow eyes have a more crowded anterior segment than POAGNA eyes, especially the entrance of the angle. In addition, APAC fellow group has a shallower ACD in comparison to POAGNA group. And, when the illumination conditions change from light to dark the iris-lens contact decreases in both groups.
This PDF is available to Subscribers Only