Clinical trial NCT04977102: A Randomized Study of Intraocular Caliper-assisted Capsulotomy for Age-related Cataract Patients With Corneal Limbus Opacity
Official title: A Randomized Controlled Trial Comparing Intraocular Caliper-assisted Capsulotomy Versus Verion Navigation System-assisted Capsulotomy for Age-related Cataract With Corneal Limbus Opacity
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Cataract Extraction
Lead sponsor: Zhongshan Ophthalmic Center, Sun Yat-sen University
Sponsor class: OTHER
First posted: 2021-07-26
Enrollment: 74
Sex: ALL
Minimum age (years): 55
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: OTHER

Brief summary: The purpose of this study is to compare the accuracy of capsulotomy assisted by intraocular caliper and Verion navigation system in phacoemulsification surgery and postoperative visual quality for age-related cataract patients with corneal limbus opacity.

Detailed description: Continuous curvilinear capsulorhexis (CCC) is an important and technically challenging procedure in cataract surgery. Too large or too small capsulorhexis can increase the incidence of intraoperative and postoperative complications.

In recent years, the image projection device Verion navigation system has been reported that it can improve the repeatability and accuracy of capsulorhexis via projecting a pre-set size ring to guide capsulorhexis. However, we found that for the patients with corneal geriatric ring, pterygium or limbal lesions leading to unclear limbal boundary, the projected capsulorhexis will deviate from the center, resulting in capsulorhexis is off center in clinical practice. Our self-developed intraocular caliper, which is modified on the conventional intraocular irrigation needle, can accurately measure the size of capsulorhexis, and mark the position and boundary of capsulorhexis on the lens anterior capsule to guide capsulorhexis, thus significantly improves the accuracy and centricity of capsulorhexis.

The purpose of this study is to compare the centricity and accuracy of intraocular caliper-assisted capsulorhexis in phacoemulsification for age-related cataract patients with corneal limbus opacity with that of Verion projection navigation system.

Eligibility criteria: Inclusion Criteria:

* Adults aged 55 to 80 years with age-related cataract with pterygium, Corneal geriatric ring, and corneal limbus opacity;
* Pupil diameter ≥ 6.5mm after pupil dilation;
* Lens nuclear opacity grading score (LOCS III) lower than 4.0.

Exclusion Criteria:

* Patients had previous intraocular surgery;
* Patients with a diagnosed eye disease that may affect the functions of lens suspensory ligament such as previous ocular trauma, lens subluxation, pseudoexfoliation syndrome, retinal pigment degeneration;
* Patients had other ocular diseases that impair visual function include optic neuropathy, uveitis, and tumor.
* Refused to participate the study.

Primary outcomes:
measure: Distance between pupil center and capsulorhexis center
timeFrame: During the surgery
Secondary outcomes:
measure: Uncorrected and corrected visual acuity
timeFrame: One month after surgery
measure: Ideal ratio of capsulorhexis
timeFrame: During the surgery
measure: Grades of capsulorhexis-IOL overlap
timeFrame: During the surgery
measure: Deviation of horizontal and vertical diameter of capsulorhexis from the target diameter (5.3 mm)
timeFrame: During the surgery
measure: Horizontal and vertical diameter of capsulorhexis
timeFrame: During the surgery
measure: Intraocular lens tilt
timeFrame: One month after surgery
measure: Intraocular lens decentration
timeFrame: One month after surgery
measure: Intraocular aberrations
timeFrame: One month after surgery
measure: Distance between pupil center and capsulorhexis center
timeFrame: One month after surgery
Other outcomes:
Locations:
city: Guangzhou
country: China
facility: Zhongshan Ophthalmic Center, Sun Yat-sen University
Study officials:
References: