Abstract:AIM: To determine the correlation among horizontal ciliary sulcus(HCS)diameter, vertical ciliary sulcus(VCS)diameter and corneal diameter in different anterior chamber depth(ACD)levels from patients with low to moderate myopia.METHODS: Retrospective study. A total of 78 patients(129 eyes)with low to moderate myopia who had preoperative examination of implantable contact lens(ICL)implantation in Shanghai Bright Eye Hospital from April 2021 to April 2022 were included. HCS, VCS and white to white(WTW)were measured and compared. Patients were divided into shallow ACD group(2.8 mm ≤ ACD ≤3.2 mm), medium ACD group(3.2 mm < ACD ≤3.4 mm)and deep ACD group(ACD > 3.4 mm)based on the ACD obtained by Pentacam. The HCS, VCS and WTW within and among groups were compared, and the correlation of WTW, HCS and VCS among each group was analyzed by Pearson and linear regression equation.RESULTS: There was no statistical difference in WTW and HCS overall and in groups with different ACD(P>0.05), while there was difference between VCS and both HCS and WTW(P<0.01). The WTW had a correlation with both HCS and VCS in each group, while correlation between WTW and VCS was weak in the deep ACD group(r=0.470, R2=0.221, P<0.01). Furthermore, the WTW, HCS and VCS in the shallow ACD group were statistically different from those in the medium and deep ACD groups(P<0.01).CONCLUSION: The WTW was suggested predicting HCS rather than perfectly replacing HCS before patients had the ICL operation among patients with low to moderate myopia. The predictability of VCS would decline as the ACD depth increasing, predicting VCS by WTW was not recommended.