Anterior Chamber Angle Changes And Its Associated Factor After Icl Implantation In Eyes With Shallow Anterior Chambers

To investigate anterior chamber angle (ACA) changes after implantable collamer lens (ICL) implantation in eyes with shallow anterior chamber depth (ACD) and the effect of vault size on ACA changes.

Eye & ENT Hospital of Fudan University

Prospective study. A total of 120 eyes of 120 patients who underwent ICL implantation were divided into shallow (ACD≤3.0 mm, n=60) and normal ACD groups (ACD>3.0 mm, n=60). Trabecular-iris angle 500 (TIA₅₀₀), angle opening distance 500 (AOD₅₀₀), trabecular-iris space area (TISA₅₀₀), angle opening distance circumference area 500 (AODA₅₀₀), trabecular-iris circumference volume 500 (TICV₅₀₀), and anterior chamber volume (ACV) measured by swept source optical coherence tomography preoperatively and at 3 months postoperatively were compared within and between groups and according to vault size.

Relative to the preoperative values, the TIA₅₀₀, AOD₅₀₀, and TISA₅₀₀ values decreased significantly in both groups (all p<0.01). Similarly, the AODA₅₀₀, TICV_500, and ACV values decreased by 52.1%, 48.2%, and 38.9%, respectively, in the shallow ACD group (all p<0.001), and by 59.2%, 56.6%, and 37.4%, respectively, in the normal ACD group (all p<0.001). However, the reduction in all ACA parameters in the shallow ACD group in each meridian was significantly lower than that in the normal ACD group, both for low (all p≤0.005) and high vaults (all p≤0.004). Correlation analyses indicated that vault size was positively correlated with the decrease in ACA parameters in both groups (all p<0.05). 

Anterior segment structure were more crowd in patients with a shallow ACD. We recommend careful monitor of the ACA in the superior-nasal quadrant, particularly for high vault.