Assessment of clinical efficacy and safety of ICL implantation in patients with relatively shallow anterior chamber depth in early and midterm postoperative time.

OBJECTIVE

To investigate the clinical effect and safety of Implantable Collamer Lens (ICL) implantation in myopic patients with relatively shallow anterior chamber depth (ACD).

METHODS

Retrospective analysis, comparative, non-interventional case series. Patients with myopia who underwent ICL implantation were included in the study and were categorized into two groups: one with a relatively shallow ACD (2.60 mm ≤ ACD ＜ 2.80 mm) and the other with a normal ACD (ACD ≥2.80 mm). Each group comprised 51 eyes and were reviewed for at least 6 months. To evaluate preoperative and postoperative visual acuity, intraocular pressure (IOP), central vault, ACD, endothelial cell density (ECD) and anterior chamber angle parameters [ trabecular iris angle (TIA), angle opening distance at 500 μm and 750 μm (AOD500, AOD750), trabecular iris space area at 500 μm and 750 μm (TISA500, TISA750) ]. Analyze the trend of postoperative data changes of 1 week, 1 month, 3 months, and at least 6 months. Patients in relatively shallow ACD with vault <100 μm or >1000 μm were performed detailed follow-up.

RESULTS

The postoperative uncorrected distance visual acuity (UDVA) and best corrected visual acuity (BCVA) surpassed the preoperative BCVA in two groups. The group differences of effectiveness index (EI) was  = 0.409 and of safety index (SI) was  = 0.563. The EI were 1.07 and 1.09, SI were1.10 and 1.21. Postoperative vision and refractive error were effectively corrected. The preoperative and postoperative IOP and ECD values of the two groups were within the normal range, and the preoperative and postoperative differences and the group differences of IOP and ECD were  = 0.649,  = 0.501,  = 0.222,  = 0.276. The ACD in two groups were reduced by approximately 25 % and 26 %, the nasal and temporal TIA were reduced to 45 % and 50 % approximately. The nasal and temporal AOD500, AOD750, TISA500, and TISA750 in the relatively shallow ACD group were reduced 40 % approximately and in the normal ACD group were reduced to 30 % approximately. All the preoperative and postoperative differences and the group differences of anterior segment parameters were statistically significant (all  < 0.01), with more significant anterior segment changes in normal ACD group.The postoperative data in two groups showed that when the follow-up time was prolonged, the central vault was decreasing, and the postoperative ACD was increasing, the postoperative TIA increased slowly in relatively shallow ACD group and decreased slowly in normal ACD group, temporal TIA were greater than nasal TIA, with no significant variation. There were four eyes in the relatively shallow ACD group in the remarkable abnormal postoperative central vault. Three eyes had second operation: one eye had an ICL alignment, and two eyes had ICL replacement.

CONCLUSION

Patients with relatively shallow ACD who underwent ICL implantation had fine postoperative clinical efficacy and safety.