Long-shaft Vitrectomy Probe in Highly Myopic Eyes

Study Overview
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Brief Summary
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This study aimed to compare the safety and efficacy of vitrectomy probe with different shaft lengths in vitreoretinal surgery of highly myopic patients. In this randomized controlled study, highly myopic patients who had axial length more than 26 mm and needed vitreoretinal surgery will be enrolled. The enrolled patients will be randomized into 30 mm shaft length group(trial group) and 27mm shaft length group(controlled group). We will compare the rate of wound leakage, hypotony, subconjunctival hemorrhage, probe bending, trocar removal, and endophthalmitis between the two groups. We would like to evaluate the efficacy and safety of the 30 mm shaft length vitrectomy probe.

Official Title
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The Surgical Outcomes of Long-shaft Vitrectomy Probe for Vitreoretinal Diseases in Highly Myopic Eyes

Conditions
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Retinal Diseases, High Myopia

Intervention / Treatment
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* Procedure: 25 gauge pars plana vitrectomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Highly myopic patients (axial length > 26mm) with vitreoretinal diseases or maculopathy requiring pars plana vitrectomy Exclusion Criteria: Previous history of pars plana vitrectomy Surgical plan combining encircling buckle Silicone oil or perfluorocarbon liquid use intraoperatively Previous history of pterygium surgery, trabeculectomy, glaucoma surgery Previous history of corneal, conjunctival, or scleral laceration History of connective tissue disease

Ages Eligible for Study
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Minimum Age: 20 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: study group<br>Highly myopic patients with vitreoretinal disease requiring pars plana vitrectomy. The 30mm (shaft length) vitrectomy probe (25 gauge) would be used in the surgery. | Procedure: 25 gauge pars plana vitrectomy<br>* 25 gauge pars plana vitrectomy<br>|
| Active Comparator: control group<br>Highly myopic patients with vitreoretinal disease requiring pars plana vitrectomy. The 27mm (shaft length) vitrectomy probe (25 gauge) would be used in the surgery. | Procedure: 25 gauge pars plana vitrectomy<br>* 25 gauge pars plana vitrectomy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| trocar removal rate | trocar removal would be performed if the length of vitrectomy probe was not adequate | intra-operative | 
| operation time | record the operation time and time of core vitrectomy | intra-operative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| instrument bending | record the occurrence of instrument bending | intraoperative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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High myopia, Pars plana vitrectomy, Vitreoretinal disease