This prospective randomized controlled trial will be conducted to investigate Clareon intraocular lens (IOL) stability in vitrectomy patients. The investigator plans to target the patients undergoing cataract surgery. A randomized study will be conducted with 2 arms, one with Clareon IOL versus a second arm using the Tecnis 1 In this non-inferiority study, the investigator will compare Clareon IOL from Alcon with the existing Tecnis 1 IOL from Precision Lens which is the commonly used intraocular lens in combined vitrectomy cases in Hong Kong.

All patients will undergo standard phacoemulsification cataract extraction with Clareon IOL or Tecnis 1 IOL by an experienced cataract surgeon. Followed by vitrectomy to treat either, epiretinal membrane or vitreous hemorrhage.

All patients returned for follow-up visits at 1 week, 1 month, and 6 months after surgery for ophthalmic assessments including:

• Visual acuity measured by Early Treatment of Diabetic Retinopathy Study (ETDRS) chart
• Refraction
• Axial movement and tilt measured by Pentacam (OCULUS Optikgeräte GmbH, Germany) using the Sasaki method. The Scheimpflug image of the horizontal cross-section and the vertical cross-section of the IOL will be selected for measurement. Central ACD will be measured as the distance between the central corneal posterior endothelium to the anterior surface of IOL. The subtraction in ACD between two visits indicated forward or backward axial movement of the IOL.
• Decentration will be measured from the center of the IOL anterior surface to the pupillary axis, which will be perpendicular to the line between the two anterior chamber angles and through the midpoint of the line.
• Tilt will be measured as the angle between the IOL axis and the perpendicular visual axis.
• Any surgical complications and post-op complications will be documented.

Inclusion Criteria:

• Patients with a diagnosis of senile cataracts and epiretinal membranes or vitreous hemorrhage
• Age between 50 and 80 years.

Exclusion Criteria:

• Diagnosis of vision-impairing diseases including uveitis, glaucoma and corneal pathologies resulting in high astigmatism, severe refractive error (preoperative spherical equivalent of either eye >-6.00D or +5.00D);
• Diagnosis of possible lenses instability including History of ocular trauma, Pseudoexfoliation syndrome; past refractive surgery or other ophthalmic surgery;
• Known Capsular or zonular disorders that might affect the post-operative centration of IOLs, e.g., pseudo-exfoliation syndrome or Marfan syndrome;
• Surgical complications including severe hyphema, iris injury, repeated IOL implantation during surgery, failure to achieve in-the-bag IOL implantation, posterior capsular rupture, usage of tamponade (gas or oil) and corneal sutures.
• Difficulty in obtaining IOL measurements (eg. Small pupil, corneal opacities, patient cooperation)

By direct contact to the corresponding author or PI

5 years after the study ends

Case by case

Patients are randomised and masked from the treatment