To evaluate the relationship between anterior chamber biometric parameters (angle-to-angle diameter ATA and anterior chamber width ACW) and the sulcus-to-sulcus diameter (STS) in myopic patients with varying axial length (AL). A 50-MHz ultrasound biomicroscopy (UBM) device measured STS at the 0° and 90° meridians in the right eyes of 77 Chinese patients with high myopia and an anterior chamber depth greater than 2.80 mm. Swept-source optical coherence tomography device (CASIA2; Tomey) measured ATA and ACW at the 0°, 45°, 90°, and 135° meridians, whereas corneal topography measured the horizontal white-to-white diameter (WTW-0°). Vertical STS, ATA, and ACW measurements were significantly longer than their horizontal counterparts (P < .001). Differences in STS and ACW between vertical and horizontal meridians were comparable (P = .503), whereas ATA differences was more pronounced than that of STS (P = .032). Both STS-0° and STS-90° were significantly greater than WTW-0°, ATA, and ACW at their respective meridians (P ⩽ .016), except for STS-0° versus ACW-0° (P = .127). Correlations between STS-0°/STS-90° and WTW-0° were weaker than those with ACW or ATA. STS-0° exhibited the strongest correlation with ACW-0°, whereas STS-90° correlated best with ACW-45°. For patients with AL shorter than 28.5 mm, no significant differences existed between STS-0° and WTW-0°/ATA-0°/ACW-0°. In contrast, for those with AL greater than 28.5 mm, only ACW-0° was comparable to STS-0°. At the vertical meridian, only ACW had no significant differences compared to STS for patients with different ranges of AL. In Chinese patients who are potential candidates for Implantable Collamer Lens implantation, ACW shows better concordance with STS than ATA and WTW-0°. The reliability of WTW-0° for estimating STS decreases with increased AL, making ACW more suitable for STS estimation in patients with AL greater than 28.5 mm, especially at non-horizontal meridians.
Huang et al. (Fri,) studied this question.