Abstract:AIM:To investigate the relationship among lens parameters and their correlation with ocular anatomic characteristics in myopia patients implanted with posterior-chamber phakic implantable collamer lens(Phakic-ICL).
METHODS:Retrospective study. A total of 46 myopia patients(46 eyes)who underwent Phakic-ICL implantation were collected in the Wuxi Huaxia Eye Hospital from June 2022 to June 2023. Preoperative evaluation of ocular anatomical characteristics included corneal central thickness(CCT), anterior chamber depth(ACD), axial length(AL), white-to-white(WTW), horizontal sulcus to sulcus(STSH), horizontal angle to angle(ATAH), and vertical sulcus to sulcus(STSV), vertical angle to angle(ATAV). Furthermore, lens parameters included horizontal crystalline lens rise(CLRH), vertical CLR(CLRV)and vertical lens thickness(LTV). The difference, consistency and correlation of the above parameters were analyzed.
RESULTS:Except for differences between WTW and STSV, STSH and ATAV, which were not statistically significant(all P>0.05), the other horizontal and vertical ocular anatomical characteristics were statistically significant(P<0.05). CLRH and CLRV had statistically significant difference(P<0.01), while LTH and LTV were not statistically significant difference(P>0.05). Bland-Altman results revealed that the anatomical characteristics in the horizontal or vertical diameters showed poor consistency. The consistency between CLRH and CLRV was poor. There was consistency between LTH and LTV, with the 95% limits of agreement(LoA)between the differences ranging from -0.21 to 0.28 mm, and the proportion of out-of-line points off the 95% LoA was 4.35%. Pearson correlation analysis revealed that there were correlations between the anatomical characteristics of the horizontal and vertical diameters(P<0.01). Meanwhile, there was no correlation between the anteroposterior diameters(P>0.05). There were correlations between the lens parameters(P<0.05), excepted for the CLRH, LTH and LTV, which had no correlation. AL correlated with the anatomical characteristics of the horizontal and vertical diameters(P<0.05), but it had no correlation with lens parameters(P>0.05). Multiple linear regression analysis revealed that LT=0.419+0.017×age-0.548×ACD+0.371×ATAH+0.884×CLRV, CLRH=-0.443+0.809×CLRV, CLRV=-0.092-0.200×ATAH+0.560×CLRH(corrected R2=0.458, 0.482, 0.589, respectively).
CONCLUSION:Horizontal and vertical diameters were not interchangeable. CLRH and CLRV were not interchangeable, while LTH and LTV were interchangeable. Partial lens parameters, WTW, STS, and ATA were correlated with ACD. Finally, age, ACD, ATAH, and CLRV influenced LT.