Clinical Application Comparison of Two Femtosecond Laser Systems

Comparison of Perioperative Parameters of Femtosecond Laser-assisted Cataract Surgery Using Two Laser Systems: a Randomized Clinical Trial

The goal of this clinical trial is to compare the perioperative parameters of femtosecond laser-assisted cataract surgery (FLACS) using two laser systems.

Participants will:

Undergo FLACS using LenSx or Z8 femtosecond laser system Visit the clinic before the operation and 1 day, 1 week, and 1 month after the operation for checkups and tests Complete clinical measurements and dry eye questionnaires

Study Overview

• Status: Recruiting
• Conditions: Cataract
• Intervention / Treatment: Procedure: LenSx; Procedure: Z8

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Kai Wang; Phone Number: +86 57187783897; Email: wmzcmxxy@zju.edu.cn

Study Locations

• China
  • Zhejiang
    • Hangzhou, Zhejiang, China, 310009
      • Recruiting
      • Second Affiliated Hospital, School of Medicine, Zhejiang University
      • Contact: Kai Wang; Phone Number: +86 57187783897; Email: wmzcmxxy@zju.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Chinese Han patients aged 40 years or older
2. clinical diagnosis of age-related cataracts;
3. underwent FLACS with insertion of a posterior chamber IOL for the first eye.

Exclusion Criteria:

1. coexisting macular pathologies such as epiretinal membrane, macular hole or edema, or age-related macular degeneration. Patients with OCT scans of poor quality were excluded;
2. preoperative flare of more than 15ph/ms11, ECD<2000cells/mm2 or any other corneal pathologies;
3. coexisting serious ocular diseases including uveitis, uncontrolled glaucoma, optic atrophy , amblyopia, retinopathies, or inflammatory pathology of the eye;
4. history of intraocular trauma, surgery, or retinal laser procedures;
5. usage of systemic or topical steroids or NSAIDs within one month prior to surgery;
6. patients with diabetes or any other systemic diseases that might confound the results or increase the risk for postoperative inflammation;
7. intraoperative complications such as capsule tear, hyphema, vitreous loss, iris manipulation, or miosis after laser pre treatment requiring intracameral injection of epinephrine;
8. ocular conditions contraindicating FLACS including poorly dilated pupils (<5.0mm), narrow palpebral fissure, small hyperopic eyes with steep cornea (difficult to achieve suction), severe conjunctival chalasis, nystagmus, or lack of cooperation;
9. potentially pregnant women;
10. known sensitivity to concomitant medications used during perioperative period, participation in other clinical trial during the time of visit, or poor cooperation in diagnostic tests or non-compliance at follow-up.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: LenSx group	Procedure: LenSx; Participants undergo FLACS using LenSx femtosecond laser system
Experimental: Z8 group	Procedure: Z8; Participants undergo FLACS using Z8 femtosecond laser system

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ocular staining score	The ocular staining score ranged from 0 to 12. A score of 0 indicated no corneal or conjunctival staining with fluorescein or lissamine green dye, respectively. A score of 12 indicated severe staining of the cornea and conjunctiva with confluent and central fluorescein staining, the presence of corneal filaments, and confluent areas of lissamine green of the bulbar conjunctiva of greater than or equal to 4 mm2.	1 month after operation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ocular staining score	The ocular staining score ranged from 0 to 12. A score of 0 indicated no corneal or conjunctival staining with fluorescein or lissamine green dye, respectively. A score of 12 indicated severe staining of the cornea and conjunctiva with confluent and central fluorescein staining, the presence of corneal filaments, and confluent areas of lissamine green of the bulbar conjunctiva of greater than or equal to 4 mm2.	1 day and 1 week after operation
phacoemulsification time		in the operation
ultrasound power		in the operation
vacuum docking time		in the operation
femtosecond laser emission time		in the operation
femtosecond laser-assisted capsulorhexis time		in the operation
femtosecond laser-assisted pre-chop time		in the operation
surgical time		in the operation
surgical complication		in the operation
DEQ-5 questionnaire	The dry-eye questionnaire-5 (DEQ-5) is a validated questionnaire that has been shown to discriminate between different severities of dry eye. Participants self-assessed the frequency and severity of eye discomfort, eye dryness, and watery eyes experienced during the evening of a typical day within the last month. Responses were given using a Likert scale with scoring criteria from 0 = never experienced the symptom to 5 = extremely severe experience of symptom. The sum of the scores from the five questions was used in the analysis.	1 week and 1 month after the operation
OSDI questionnaire	Ocular surface disease index (OSDI) is a widely accepted questionnaire on subjective symptoms in patients with dry eyes. It consisted of 12 questions on eye-related symptoms, vision-related function, and environment-related symptoms. Each question is evaluated according to the frequency of occurrence: never, 0 point; occasionally, 1 point; often, 2 points; most of the time, 3 points; all the time, 4 points. Not all the 12 questions needed to be answered. If the question is that the patient didn't participate in the activity or the environment that would not be in the case, it would not be answered and scored. The final score is calculated according to the formula: OSDI values=(sum of all survey items)×100/(answered survey items)×4.	1 week and 1 month after the operation
tear meniscus height	The tear meniscus assessment height was measured with the Ocular Surface Analyser (SBM Sistemi, Orbassano, Italy)	1 day, 1 week, and 1 month after the operation
noninvasive tear film breakup time	Noninvasive tear film breakup time was assessed automatically using the Ocular Surface Analyser (SBM Sistemi, Orbassano, Italy). The participants were instructed to blink naturally two times and then to cease blinking until instructed to blink again. Three measurements were performed for each eye and the average for each eye included for analysis.	1 day, 1 week, and 1 month after the operation
tear-film assessment	The tear-film assessment was assessed with the Ocular Surface Analyser (SBM Sistemi, Orbassano, Italy).	1 day, 1 week, and 1 month after the operation
Schirmer I test	The Schirmer I test was carried out under natural light. A 5 mm×35 mm Schirmer test strip was placed in the middle and outer 1/3 junction of the lower conjunctival sac of the affected eye without anesthesia. The patient was asked to close eyes gently. After 5min, the strip was removed and the wet length of the strip was measured. Values less than 5 mm are indicators for dry eye syndrome.	1 day, 1 week, and 1 month after the operation
visual acuity		1 day, 1 week, and 1 month after the operation
intraocular pressure		1 day, 1 week, and 1 month after the operation

Collaborators and Investigators

• Sponsor: Second Affiliated Hospital, School of Medicine, Zhejiang University

Study record dates

Study Major Dates

• Study Start (Actual): October 29, 2024
• Primary Completion (Estimated): August 31, 2025
• Study Completion (Estimated): October 31, 2025

Study Registration Dates

• First Submitted: December 15, 2024
• First Submitted That Met QC Criteria: December 23, 2024
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 23, 2024
• Last Verified: October 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Lens Diseases; Cataract
• Other Study ID Numbers: 2024-1312

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No