Effects of Transient Prone Position on Vault and Anterior Chamber Angle in ICL Implanted Patients

PURPOSE: To evaluate the effects of transient prone position on vault and anterior chamber angle parameters in ICL implanted patients. METHODS: 40 eyes of 20 ICL implanted patients with at least 1 month of follow-up were included in the present study. The central ICL vault and anterior chamber parameters including angle opening distance at 500 (AOD500) were measured with the Visante anterior segment optical coherence tomography (OCT) (Carl Zeiss, Dublin, CA) in both the sitting and prone positions by tilting the OCT 90 degrees in the vertical axis and having the patient fixate downwards towards the floor. RESULTS: The mean central vault was 0.55 +/- 0.21 mm (SD) and 0.59 +/- 0.21 mm (SD) in the sitting and prone positions, respectively (p < 0.0001). The nasal and temporal AOD500 were 0.26 +/- 0.11 mm and 0.28 +/- 0.08 mm, respectively in the sitting position, which decreased to 0.24 +/- 0.10 mm and 0.26 +/- 0.08 mm in the prone position, however, both were not statistically significant (p = 0.08, p = 0.09). AOD500 was inversely correlated with vault (r = -0.47; p = 0.0024). There were no significant correlations between increase of vault and anterior chamber depth or white to white nor ICL vault. CONCLUSIONS: Transient prone positioning of ICL implanted patients can induce a significant increase in ICL vault.

Clinical Significance of Ultrasound Biomicroscopy in Early Stage of Traumatic Hyphema

PURPOSE: To evaluate the clinical significance of angle-opening distance 500 (AOD500) using ultrasound biomicroscopy (UBM) in the early stage of traumatic hyphema. METHODS: The participants of this study were 46 hospitalized traumatic hyphema patients. We measured the quantity of initial blood clotting using a slit-lamp and the range of angle recession, AOD500 using UBM and then reviewed the relationship between the two. RESULTS: The difference of AOD500 in the traumatic and the non-traumatic eye measured by UBM at admission increased significantly in the wider recessed angle group (p=0.008), but did not increase at a statistically significantly level in the larger initial blood clot grade group (> or =Grade 2). CONCLUSIONS: These results suggest that the measurement of the angle-opening distance of both eyes using UBM will aid in evaluating the range of angle recession in patients in the early stage of traumatic hyphema.

Changes of Anterior Chamber Depth and Angle After Cataract Surgery Measured by Anterior Segment OCT

PURPOSE: To report the change of anterior chamber parameters according to cataract severity after cataract surgery and to determine its relationship to the severity of cataract by using anterior segment optical coherence tomography. METHODS: We measured the anterior chamber parameters in 19 eyes of 14 patients before, 1 week after, and 1 month after cataract surgery by slit lamp-adapted optical coherence tomography (SL-OCT). The measured parameters were as follows : the anterior chamber depth (ACD), the angle-opening distance 250 micrometer from the scleral spur (AOD250), the angle-opening distance 500 micrometer from the scleral spur (AOD500), and the trabecular-iris angle (TIA). We analyzed the relationship between the severity of cataract and the change of the anterior chamber parameters. RESULTS: The ACD, AOD250, AOD500, and TIA increased significantly at postoperative 1 week (P=0.000, 0.002, 0.005, 0.022) and 1 month (P=0.000, 0.004, 0.001, 0.002). The preoperative parameters were negatively correlated with the differences between the postoperative 1 week and preoperative parameters (gamma=-0.834, -0.591, -0.421, -0.826) and between postoperative 1 month and preoperative parameters (gamma=-0.659, -0.700, -0.770, -0.821). The change of parameters at postoperative 1 week (by N P=0.959, 0.916, 0.824, 1.000, by C P=0.454, 0.665, 0.578, 0.578) and 1 month (by N P=0.858, 0.973, 0.959, 0.959, by C P=0.999, 0.207, 0.950, 0.981) were not significantly different according to the severity of cataract (N, C). CONCLUSIONS: Our results showed that cataract surgery significantly deepened the anterior chamber and widened its angle. The shallower and narrower the preoperative anterior chamber depth and angle were, respectively, the greater the postoperative changes of anterior chamber depth and angle were.