Variation of Angle Parameters in Asians: An Anterior Segment Optical Coherence Tomography Study in a Population of Singapore Malays

Abstract

In this Malay population, angle width measured by AS-OCT was smaller in women than in men, and in eyes with shorter axial length and shallower ACD.

Anterior segment optical coherence tomography of acute primary angle closure

“…Our results also imply that the risk for APAC increases from a group of eyes with normal anterior segment measurements to a group of eyes that have moderately shallow anterior chambers and contralateral eyes that have APAC, to a group of eyes with markedly shallow anterior chambers and APAC ( Table 5). The results of our study are also in agreement with recent studies showing that optical coherence tomography is able to image and measure the anterior chamber structure and dimensions in normal eyes and eyes with APAC in subjects of different ethnic background [24][25][26][27][28][29][30]. Interestingly, we found, by OCT measurement, that the anterior chamber angle was closed most often in the nasal quadrant, while, as a corollary, the temporal quadrant was the region least often affected (Table 4).…”

Anterior Segment Parameters Associated to Acute Glaucoma with Slit Lamp Optical Coherence Tomography

“…The female predispositions to APAC agree with findings of other studies where the angle width measurements are smaller in women [4] [5].…”

“…Similarly, Nolan et al [14] showed that the inferior angle is closed more frequently than the nasal or temporal quadrants, while Sakata et al [15] found that the superior quadrant is the narrowest. Besides, Amerasinghe et al [4] found that the angle is narrower temporally than nasally.…”

“…Additionally, Amerasinghe et al [4] confirm that the angle width is smaller in eyes with shallower ACD, which means that the iris-lens diaphragm is more anteriorly located in APAC fellow eyes; so it could be related to the anatomic predisposition to acute primary angle closure. Foo et al [10] also demonstrated that the angle width is largely dependent on variations in ACV.…”

Association Between Baseline Angle Width and Induced Angle Opening Following Prophylactic Laser Peripheral Iridotomy

“…Amerasinghe et al recommended the use of AOD as an ASOCT surrogate for gonioscopy after demonstrating that AOD is more highly correlated with the clinical gonioscopic assessment of angle width than TISA. 22 Narayanaswamy et al also supported the utility of AOD as a useful angle measurement for identifying individuals with gonioscopic narrow angles in gradable ASOCT images. The same group did caution that AOD is influenced by iris contour and when used in isolation could result in a false interpretation of the angle status.…”