VITAL - "Visual Improvement With Toric Asymmetrical Lenses": Enhancing Vision in Irregular Corneas
Trial Snapshot
- Phase
- Not Applicable
- Status
- Recruiting
- Sponsor
- Enrollment
- 15
- Locations
- 1
- Primary Endpoint
- Change of Astigmatism
Study Overview
Brief Summary
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.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 21 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
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
Arms & Interventions
AMILens Individual Implantation
An acrylic hydrophilic, one piece 4-loop haptic, monofocal, toric IOL (AMILens Individual, AMIPLANT GmbH, Germany) will be implanted into the capsular bag after removal of the of the natural lens. This IOL is CE-certified. Asphericity and dioptric power of the IOL are customized for each individual eye.
Intervention: AMILens Individual (Device)
Outcomes
Primary Outcomes
Change of Astigmatism
Time Frame: 4-8 weeks post-surgery
The change of astigmatism is defined by the difference of the postoperative total refractive/ocular astigmatism (assessed via subjective refraction) to the preoperative corneal astigmatism (assessed via the utilized measurement devices). Reduction in total ocular (refractive) astigmatism will be quantified as both absolute reduction (Diopter) and relative reduction (%). Descriptive statistics will include mean, standard deviation, median, interquartile range, and range. Normality will be tested using the Shapiro-Wilk test and Q-Q plots. If normally distributed: comparisons between preoperative and postoperative values will be assessed with a paired t-test. If not normally distributed: the Wilcoxon signed-rank test will be applied. Results will be presented with 95% confidence intervals. As this is an exploratory study, p-values will be reported descriptively, and values below 0.05 will not be interpreted as statistically significant.
Secondary Outcomes
- Agreement of measured variables for astigmatism across devices(4-8 weeks post cataract surgery)
- Change of higher order optical aberrations (HOAs)(4-8 weeks post cataract surgery)
- Surgically induced corneal astigmatism (SIA)(From enrollment to the end last study visit (4-8 weeks post surgery))
- Postoperative uncorrected and best-corrected distance visual acuity(4-8 weeks post cataract surgery)