Overview
Cataract surgery in patients with irregular corneas presents unique challenges, primarily due to the high variability in keratometry and corneal tomography measurements, which complicates accurate intraocular lens (IOL) calculations. In these patients, therapeutic options are currently limited to either non-toric IOLs and rigid contact lenses postoperatively or conventional toric IOLs for the reduction of total astigmatism within cataract surgery. While conventional toric IOLs may be beneficial in selected cases with a stable astigmatic pattern and clear axis, their effectiveness is largely limited, as significant irregularity and higher order aberrations reduce predictability, accuracy of formulae, and refractive outcomes. Therefore, the development of a reliable method to reduce total astigmatism - including irregular components - would represent a major advancement, potentially improving both visual function and patient quality of life. The aim of this exploratory study is to evaluate the effectiveness of customized toric intraocular lenses (AMILens Individual, AMIPLANT GmbH, Germany) in reducing total corneal astigmatism in patients with a significant irregular astigmatic component. These lenses are designed to address corneal aberrations up to the 6th Zernike order, thereby extending correction beyond the capabilities of conventional toric IOLs. To our knowledge, no clinical study has yet investigated this novel approach.
Eligibility
Inclusion Criteria:
- Age 21 years or older
- Scheduled cataract surgery
- At least 1.75 D of total astigmatism in the CASIA2 measurement
- At least 0.75 D of asymmetry or higher order irregularity within the 6mm zone of the real (total) index corneal refractive map of the CASIA2 measurements
Exclusion Criteria:
- Relevant central corneal scars
- PEX, previous ocular surgery, severe trauma or any pathology that could lead to an unstable capsular bag
- Combined surgery (cataract plus glaucoma/vitreoretinal/corneal surgery)
- Postoperative best corrected distance visual acuity below 0.3 Snellen decimal
- Pregnancy