Evaluation of intraocular lens subluxation after cataract surgery in patients with zonular weakness

To evaluate the intraocular lens (IOL) subluxation after cataract surgery in patients with zonular weakness.

This study assessed the medical records of cataract patients with zonular weakness treated at Naresuan University Hospital, Thailand-country between November 2014 and October 2019. Preoperative and postoperative values of uncorrected visual acuity (UCVA), refractive error, corneal refractive power (k-value), axial length, and anterior chamber depth (ACD) were examined and compared. The refractive power was converted to spherical equivalent (SE). During the operation, grading of the zonular weakness was evaluated by the surgeon. The IOLs and the capsular tension rings were then inserted. The estimated error (EE) was considered as the difference between the theoretical IOL lens position (effective lens position [ELP]) and the clinical postoperative IOL position (postoperative ACD).

This study included nine participants (nine eyes) with an average age of 64.7 ± 11.42 years. The median preoperative and postoperative UCVA were 1.39 (0.94-1.82) and 0.00 (0.00-0.37) logMAR, respectively. All of the participants achieved a better postoperative UCVA than preoperative UCVA. The preoperative SE was not able to be measured using an automated refractometer. The postoperative SE of all participants had improved compared with the preoperative SE. The median preoperative and postoperative ACD were 3.15 (2.59-3.48) and 3.98 (2.93-4.33) mm, respectively. The value of postoperative ACD was significantly increased from preoperative ACD. For a subluxation of IOL position, there was a statistically significant difference between the values of ELP and postoperative ACD (P = 0.008). The mean EE was 0.96 ± 0.65 mm. The EE was a positive value in all participants, and the IOL position after cataract surgery was shifted to the front.

After cataract surgery, the UCVA of all participants was improved, and the postoperative ACD was statistically significantly smaller than ELP. The EE was positive, and the IOL position after cataract surgery was shifted to the front of the eye.