Capsular tension ring force line and intraocular lens angle on the impact of postoperative astigmatism in Marfan syndrome lens subluxation: a retrospective study

To investigate the influence of the angle between the tension ring force line and the intraocular lens (IOL) on residual astigmatism after lens replacement surgery in Marfan Syndrome (MFS) patients with subluxated lenses. We conducted a retrospective cohort study involving patients with MFS who presented with lens subluxation and subsequently underwent cataract surgery with implantation of a Capsular Tension Ring (CTR) and a single-focus IOL at the Ophthalmology Department of Union Hospital, Huazhong University of Science and Technology, from April 1, 2020, to April 1, 2024. The study included patients with confirmed MFS and lens subluxation. Data collected included preoperative anterior segment photographs and postoperative assessments of visual acuity. The analysis focused on the measurement of the angle between the CTR force line and the IOL’s long axis (TRF-IOL Angle), as well as the ocular residual astigmatism (ORA), which was determined using vector analysis methods. The study encompassed 15 patients (25 eyes) in the final analysis. The gender distribution among the patients was 68% male and 32% female. The TRF-IOL Angle was identified as a significant factor impacting postoperative residual astigmatism. A pronounced effect was observed where a TRF-IOL Angle of less than 50 degrees was associated with increased residual astigmatism, indicating a direct relationship between the angle size and astigmatism levels. No significant association was identified for angles of 50 degrees or more, suggesting a threshold effect at this angle measurement. The angle between the CTR force line and IOL is associated with residual astigmatism after lens replacement surgery in MFS patients. Our findings suggest that the TRF-IOL Angle may be a factor associated with postoperative residual astigmatism in MFS patients. Appropriate positioning of the CTR and IOL could potentially contribute to favorable astigmatic outcomes. Trial registration : This study is retrospectively registered. We have registered this study with the Chinese Clinical Trials Registry ( www.chictr.org.cn , registration number: ChiCTR2400083341).