Clinical Research of Femtosecond Laser-Assisted Cataract Surgery

Study Overview
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Brief Summary
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Since femtosecond laser was approved for cataract surgery by FDA in 2010, femtosecond laser assisted cataract surgery (FLACS) has demonstrated high precision of capsulotomy, reduced phacoemulsification power and time, and comparable refractive outcome in clinic. It is still unknown whether there are toxic substances produced due to photochemical or high-energy physical effect of femtosecond laser during FLACS.

Detailed Description
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Phacoemulsification is one of the main surgical procedures for cataract surgery owing to the advantages of small incisions and rapid recovery. However, the surgical outcome of phacoemulsification can be negatively affected due to the problem of accuracy and repeatability for capsulorhexis, and the corneal endothelial cell damage by ultrasound energy.To overcome those problems from the phacoemulsification, femtosecond laser-assisted cataract surgery (FLACS) had been used in the past few years and showed unique advantages. The purpose of this study is to investigate the preliminary clinical outcomes of femtosecond laser-assisted cataract surgery.This prospective comparative study enrolled consecutive patients,will be randomly assigned to trial group underwent FLACS and control group underwent conventional cataract surgery. The phacoemulsification time, energy, and complications during operation were recorded. The anterior capsule and aqueous humor were collected. Morphology of the cutting edge and cells of anterior capsule was assessed by light microscopy. The proteins in the aqueous humor were identified by mass spectrometry . Electrolyte in the aqueous humor was detected by a chemistry analyzer. Postoperative refraction at 1 day, 1 week, 1 and 3 months, the capsulorhexis size and corneal endothelial density at 1 and 3 months were also measured.

Official Title
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Clinical Research of Femtosecond Laser-Assisted Cataract Surgery: Randomized Clinical Trial

Conditions
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Cataracts

Intervention / Treatment
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* Procedure: femtosecond laser-assisted cataract surgery
* Procedure: conventional phacoemulsification


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: normal cornea dilated pupillary diameter greater than 6mm no local or systemic contraindications to cataract surgery Exclusion Criteria: corneal pathological changes glaucoma ocular inflammation previous ocular trauma or surgery

Ages Eligible for Study
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Minimum Age: 38 Years
Maximum Age: 86 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: trial group<br>the trial group underwent femtosecond laser-assisted cataract surgery | Procedure: femtosecond laser-assisted cataract surgery<br>* the femtosecond laser platform was used to generate capsulotomy with a diameter as described above in the control group, and lens fragmentation into 6 segments.<br>|
| Other: control group<br>the control group underwent conventional phacoemulsification | Procedure: conventional phacoemulsification<br>* continuous curvilinear capsulorhexis was performed with capsulorrhexis forceps. Following hydrodissection, phacoemulsification of the nucleus, aspiration of the residual cortex and capsular polishing were performed using a phacoemulsification machine<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the proteins in the aqueous humor after femtosecond laser operation |  | day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the electrolyte in the aqueous humor after femtosecond laser operation |  | day 1 | 
| morphology of the anterior capsule after femtosecond laser operation |  | day 1 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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femtosecond laser