Predicting axial length in patients with Marfan syndrome and ectopia lentis after modified capsular tension ring and intraocular lens implantation.

Abstract

To predict the growth of axial length (AL) in patients with Marfan syndrome (MFS) and ectopia lentis (EL). Eye and ENT Hospital of Fudan University, Shanghai, China. Consecutive retrospective case series. Eyes were evaluated that had modified capsular tension ring and intraocular lens implantation. The rate of axial length growth (RALG) was calculated using AL divided by log10-transformed age. A multivariable linear regression model of RALG was developed after validation. A total of 128 patients with Marfan syndrome (MFS) and EL were enrolled with a median follow-up duration of about three years. RALG was independent of age between 3 to 15 years old (P = 0.799) and decreased to zero thereafter (P = 0.878). Preoperative AL was associated with RALG in patients under 15 years old (P = 0.003). Beta values for the final model of RALG were as below: intercept (-9.794) and pre-operative AL (0.664). The postoperative AL was predicted as: postAL = preAL + RALG × log10((postAge + 0.6) / (preAge + 0.6)). The mean prediction error was -0.003 (95%CI, -0.386, 0.3791) mm and the mean absolute percentage error was 1.93% (95%CI, 0.73%, 3.14%). A Python-based calculator was developed to use the predicted AL in selecting IOL power and setting undercorrection. The AL growth of patients with MFS followed a logarithmic pattern and ceased at about age 15. A prediction model of postoperative AL was established for individual MFS patients between 3-15 years old, which could potentially optimize the IOL power selection.