Evaluating Presbyopia-Correcting IOLs in Complex Cataract Cases With Anterior Segment Abnormalities

Official title

Clinical Study on the Application of Presbyopia-correcting Intraocular Lenses in the Surgery of Cataract Patients With Combined Anterior Segment Structural Abnormalities

Overview

The goal of cataract surgery has evolved from simply restoring sight to providing clear and comfortable full-range vision. Traditionally, monofocal IOLs remain the routine choice for special cases with anterior segment abnormalities-such as lens subluxation, cataract with chronic uveitis, post-laser refractive cataract, and aphakia with insufficient capsular support. However, there is a growing demand among these patients for improved visual quality and spectacle independence.Currently, various presbyopia-correcting IOLs offer distinct advantages, providing more personalized options. The introduction and application of intraoperative optical coherence tomography (iOCT) ensures effective intraoperative monitoring. These advances make the precise implantation of presbyopia-correcting IOLs a promising extension to phacoemulsification in complex cataracts with anterior segment abnormalities. Nevertheless, their exact benefits regarding visual quality, safety, and patient satisfaction require systematic evaluation through rigorous prospective studies and long-term follow-up. Under strict perioperative management, this study will employ iOCT to monitor the accurate implantation of presbyopia-correcting IOLs and will assess postoperative visual quality and patient satisfaction.

Detailed description

With the evolution of refractive cataract surgery, the goal of treatment has progressed from simple visual rehabilitation to providing clear and comfortable full-range vision through the implantation of functional intraocular lenses (IOLs). Traditionally, monofocal IOLs have been the standard choice for patients with anterior segment abnormalities-such as lens subluxation, cataract with a history of chronic anterior uveitis, post-laser refractive surgery cataract, or aphakia with insufficient capsular support-to minimize adverse optical outcomes. However, these patients, who span a broad age range, increasingly desire high postoperative visual quality and reduced spectacle dependence. Modern presbyopia-correcting IOLs offer advantages in material properties, structural design, and optical performance, improving biocompatibility and reducing visual disturbances such as glare and halos, thereby expanding personalized options. The integration of intraoperative optical coherence tomography (iOCT) further enhances the precision and safety of IOL implantation.

Based on these advancements, the precise implantation of presbyopia-correcting IOLs holds promise for complex cataract cases with anterior segment abnormalities. Nevertheless, their efficacy, safety, and impact on patient satisfaction require systematic evaluation through well-designed prospective studies. This prospective study aims to assess the clinical outcomes of precisely implanted presbyopia-correcting IOLs in patients with complex cataract and anterior segment structural abnormalities, including lens subluxation, chronic anterior uveitis, post-refractive surgery status, and aphakia with inadequate capsular support. Utilizing iOCT for real-time monitoring of anterior segment anatomy, capsular stability, and effective lens position (ELP) during surgery, the study will compare visual quality, safety parameters, and patient satisfaction between presbyopia-correcting IOLs and conventional monofocal IOLs, providing evidence to support individualized IOL selection in this population.

Interventions

• Procedure Unilateral Posterior Chamber Implantation of Presbyopia-Correcting IOL
  Based on the specific characteristics and needs of each of the four patient groups, a suitable presbyopia-correcting IOL will be selected and precisely implanted unilaterally in the posterior chamber.
• Procedure Unilateral Posterior Chamber Implantation of Monofocal IOL
  Each control group will undergo unilateral posterior chamber implantation of the same-brand monofocal IOL as used in the experimental group, following conventional selection criteria.

Primary outcome measures

• Uncorrected Distance Visual Acuity (UDVA) [Time frame: Preoperatively, and postoperatively at 1 day, 1 week, 1 month, and 3 months.]
• Effective Lens Position (ELP) [Time frame: Baseline, and postoperatively at 1 month, and 3 months]
• Contrast sensitivity (at 2.5 m) [Time frame: Preoperatively, and postoperatively at 1 week, 1 month, and 3 months]
• Defocus curve (at 5 m) [Time frame: Preoperatively, and postoperatively at 1 month and 3 months]
• Optical visual quality [Time frame: Postoperatively at 1 week, 1 month, and 3 months]
• Visual Function Assessment [Time frame: Postoperatively at 1 week, 1 month, and 3 months]
• Best Corrected Visual Acuity (BCVA) [Time frame: Preoperatively, and postoperatively at 1 day, 1 week, 1 month, and 3 months]
• Uncorrected Intermediate Visual Acuity (UIVA) [Time frame: Preoperatively, and postoperatively at 1 day, 1 week, 1 month, and 3 months]
• Uncorrected Near Visual Acuity (UNVA) [Time frame: Preoperatively, and postoperatively at 1 day, 1 week, 1 month, and 3 months]

Secondary outcome measures (7)

• Intraocular pressure (IOP) [Time frame: Preoperatively, and postoperatively at 1 day, 1 week, 1 month, and 3 months]
• Pupil Diameter [Time frame: Preoperatively, and postoperatively at 1 day, 1 week, 1 month, and 3 months]
• Ocular B-scan ultrasound [Time frame: Preoperatively, and postoperatively at 1 month and 3 months]
• Dry Eye Assessment [Time frame: Preoperatively, and postoperatively at1 week, 1 month, and 3 months]
• Fundus assessment [Time frame: Preoperatively, and postoperatively at 1 week, 1 month, and 3 months]
• Endothelial cell density [Time frame: Preoperatively and postoperatively 1 month]
• Frequency of using glasses [Time frame: Postoperatively at 1 week, 1 month, and 3 months]

Eligibility criteria

Inclusion criteria

• Lens Subluxation Unilateral Implantation Group

• Patients aged 18-80 years with diagnosed lens subluxation meeting surgical indications for lens surgery, enrolled unilaterally;
• Informed consent for the study;
• Ability to comply with full follow-up;
• Kappa angle <0.5 mm, total higher-order aberration root mean square (HOA RMS) within the central 4-mm corneal zone <1 μm;
• Mesopic natural pupil diameter between 3.0 mm and 5.5 mm;
• Expected postoperative astigmatism ≤1.0 D, with target spherical equivalent between 0.00 D and ±0.75 D;
• Subjective desire to improve full-range visual function.
• Inactive Long-standing Anterior Uveitis with Cataract Unilateral Implantation Group

• Patients aged 18-80 years with diagnosed inactive long-standing anterior uveitis (quiet for ≥3 months) and cataract meeting surgical indications for lens surgery, enrolled unilaterally;
• Centered pupil without significant deformity, with expected postoperative mesopic natural pupil diameter between 2.5 mm and 5.5 mm;
• Informed consent for the study;
• Ability to comply with full follow-up;
• Kappa angle <0.5 mm, total higher-order aberration root mean square (HOA RMS) within the central 4-mm corneal zone <1 μm;
• Expected postoperative astigmatism ≤1.0 D, with target spherical equivalent between 0.00 D and ±0.75 D;
• Subjective desire to improve full-range visual function.
• Post-myopic Laser Corneal Surgery with Cataract Unilateral Implantation Group

• Patients aged 18-80 years with cataract following prior myopic laser corneal surgery meeting surgical indications for lens surgery, enrolled unilaterally;
• Informed consent for the study;
• Ability to comply with full follow-up;
• Kappa angle <0.5 mm, total higher-order aberration root mean square (HOA RMS) within the central 4-mm corneal zone <1 μm;
• Mesopic natural pupil diameter between 3.0 mm and 5.5 mm;
• Expected postoperative astigmatism ≤1.0 D, with target spherical equivalent between 0.00 D and ±0.75 D;
• Subjective desire to improve full-range visual function.
• Aphakia with Insufficient Residual Capsular Support Unilateral Implantation Group

• Patients aged 18-80 years with aphakia and insufficient residual capsular support meeting surgical indications for IOL implantation, enrolled unilaterally;
• Informed consent for the study;
• Ability to comply with full follow-up;
• Kappa angle <0.5 mm, total higher-order aberration root mean square (HOA RMS) within the central 4-mm corneal zone <1 μm;
• Mesopic natural pupil diameter between 3.0 mm and 5.5 mm;
• Expected postoperative astigmatism ≤1.0 D, with target spherical equivalent between 0.00 D and ±0.75 D;
• Subjective desire to improve full-range visual function.

Exclusion criteria

• Lens Subluxation Unilateral Implantation Group

• Patients with coexisting ocular developmental anomalies such as microphthalmos or microcornea.
• Patients with severe or progressive ocular diseases (e.g., glaucoma, diabetic retinopathy, macular degeneration) or severe optic nerve disorders.
• Patients with other organic ocular pathologies, including pathologic high myopia with fundus changes, significant pupillary abnormalities (excessively large or small pupils), severe corneal disease or scarring, high irregular astigmatism, chronic uveitis, or severe amblyopia.
• Patients with lens disorders other than subluxation and cataract.
• Patients experiencing intraoperative complications that may affect IOL position and outcome (e.g., posterior capsule rupture, iris prolapse)
• Patients with a history of prior ocular surgery such as corneal refractive laser surgery, glaucoma surgery, or vitrectomy.
• Inactive Long-standing Anterior Uveitis with Cataract Unilateral Implantation Group

• Patients with active systemic autoimmune diseases, or any systemic disease history or medication use known to significantly affect vision.
• Patients with coexisting ocular developmental anomalies such as microphthalmos or microcornea.
• Patients with severe or progressive ocular diseases (e.g., glaucoma, diabetic retinopathy, macular degeneration) or severe optic nerve disorders.
• Patients with other organic ocular pathologies, including pathologic high myopia with fundus changes, severe corneal disease or scarring, high irregular astigmatism, active uveitis, significant abnormalities of the lens capsule or zonules, or severe amblyopia.
• Patients experiencing intraoperative complications that may affect IOL position and outcome (e.g., posterior capsule rupture, iris prolapse).
• Patients with a history of prior ocular surgery such as corneal refractive laser surgery, glaucoma surgery, or vitrectomy.
• Post-myopic Laser Corneal Surgery with Cataract Unilateral Implantation Group

• Patients with coexisting ocular developmental anomalies such as microphthalmos or microcornea.
• Patients with severe or progressive ocular diseases (e.g., glaucoma, diabetic retinopathy, macular degeneration) or severe optic nerve disorders.
• Patients with other organic ocular pathologies, including pathologic high myopia with fundus changes, significant pupillary abnormalities (excessively large or small pupils), severe corneal disease, high irregular astigmatism, chronic uveitis, significant abnormalities of the lens capsule or zonules, or severe amblyopia.
• Patients experiencing intraoperative complications that may affect IOL position or outcome (e.g., posterior capsule rupture, iris prolapse).
• Patients with a history of prior ocular surgery such as glaucoma surgery or vitrectomy.
• Aphakia with Insufficient Residual Capsular Support Unilateral Implantation Group

• Patients with coexisting ocular developmental anomalies such as microphthalmos or microcornea.
• Patients with severe or progressive ocular diseases (e.g., glaucoma, diabetic retinopathy, macular degeneration) or severe optic nerve disorders.
• Patients with other organic ocular pathologies, including pathologic high myopia with fundus changes, significant pupillary abnormalities (excessively large or small pupils), severe corneal disease or scarring, high irregular astigmatism, chronic uveitis, or severe amblyopia.
• Patients experiencing intraoperative complications that may affect IOL position or outcome (e.g., iris prolapse).
• Patients with a history of prior ocular surgery such as corneal refractive laser surgery, glaucoma surgery, or posterior vitrectomy.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Treatment

Study locations

China · 1 center

• Second Affiliated Hospital, Zhejiang University School of Medicine — Hangzhou

Identifiers

NCT: NCT07321756 · 2025-1077

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗