Clinical and Biometric Factors Associated with Prediction Errors Related to Lens Position in Vitrectomized Patients

Area of Science:

• Ophthalmology
• Biomedical Engineering

Background:

• Cataract surgery requires precise intraocular lens (IOL) placement for optimal visual outcomes.
• Pars plana vitrectomy can alter the ocular environment, potentially affecting IOL position and refractive predictability.

Purpose of the Study:

• To investigate clinical and biometric predictors of refractive prediction error in patients undergoing cataract surgery with pars plana vitrectomy.
• To evaluate the influence of vitrectomy and gas tamponade on intraocular lens position and refractive outcomes.

Main Methods:

• A retrospective case series analyzed 140 eyes undergoing phacoemulsification with the ASPHINA 509 MP® IOL.
• Patients were stratified into three groups: phacoemulsification alone, phacoemulsification with vitrectomy and gas tamponade, and phacoemulsification with vitrectomy without tamponade.
• Clinical and biometric data, including axial length and lens position, were collected and analyzed.

Main Results:

• A statistically significant difference in prediction error was observed between phacoemulsification alone and phacoemulsification with vitrectomy and gas tamponade (p < 0.05).
• Mean actual lens position varied significantly across the groups (p < 0.001), with vitrectomy and gas tamponade leading to a more posterior position.
• Multilinear regression confirmed that vitrectomy and gas tamponade independently influence prediction error.

Conclusions:

• Myopic shift after vitrectomy is multifactorial, influenced by changes in effective lens position and vitreous refractive index.
• Incorporating these findings into existing formulas may improve refractive accuracy in combined cataract and vitrectomy procedures.