Observation of the Efficacy of Different Vitrectomy Systems to Treat Proliferative Diabetic Retinopathy

Study Overview
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Brief Summary
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In recent years, vitrectomy has moved toward a minimally invasive vitrectomy surgery (MIV) system, which could effectively reduce the occurrence of operation complications, while reducing the time of post-operation recovery. With an improved design of bevel tip and a high cutting rate capacity of 10000cpm, Advanced ULTRAVIT® probes potentially provide an strong technical support for the application of MIV. The new probe facilitates great control during delicate surgical maneuvers, such as separating the hyaloid from the retinal surface, dissecting fibrovascular tissue off the surface of retina. However, there was no sufficient clinical evidence to support the benefits of Advanced ULTRAVIT ® probes in the complicated vitreoretinal surgery, such as proliferative diabetic retinopathy. More importantly, there is an urgent need of clinical evidence to support 10000cpm launch and conversion which is major objective of 2021 VR growth strategies.

Detailed Description
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This exploratory study, aiming to demonstrate the beneficial of 27 Gauge probe, which can be flexibly applied as a multifunctional tool for membrane removal by reducing frequencies of switching device, reducing the traction to eyeball during device entering and leaving the eye. Moreover, the outcomes from this study would be an strong evidence to support further comparative study to comprehensively demonstrate the superior function compare to current heavily used 5K 25 gauge probe.

Official Title
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Comparison of the Efficacy of Standard 25 Gauge (25G)+ and Beveled 27 Gauge (27G)+ Vitrectomy Systems in Proliferative Diabetic Retinopathy

Conditions
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Proliferative Diabetic Retinopathy, Vitrectomy

Intervention / Treatment
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* Device: beveled 27G+ vitrectomy system
* Device: standard 25G+ vitrectomy system


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with vitreous hemorrhage and tractional retinal detachment (TRD) confirmed by fundus image and B ultrasound examination, consistent with the diagnosis of severe proliferated diabetic retinopathy (PDR). Patient that could follow up postoperatively at the clinic for 6 months more. All the surgeries were performed by one well-experienced retinal surgeon. Exclusion Criteria: Corneal lesions affecting operative field, such as corneal opacity or scar; History of vitreoretinal surgery; External eye infections; History of systemic thromboembolism; Uncontrolled hypertension or hyperglycemia; Coagulation abnormalities or currently using anticoagulant drugs other than aspirin; Unable to meet postoperative position requirements; Unable to be followed up regularly.
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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: beveled 27G+ group<br>The group of patients underwent vitrectomy with a beveled 27G+ vitrectomy system. | Device: beveled 27G+ vitrectomy system<br>* The device is a novel 27G+ vitrectomy system, whose probe tip is beveled.<br>|
| Active Comparator: 25G+ group<br>The group of patients underwent vitrectomy with a standard 25G+ vitrectomy system. | Device: standard 25G+ vitrectomy system<br>* The device is a traditional instrument, and its probe tip is flat.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the convenience in operating | The convenience will be indicated by times of ancillary instrument using, which evaluated based on the recorded surgical video. | during surgery | 
| the efficiency of stripping membrane | It will be measured by the area of membrane removed per minute by probe. | during surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| best corrected visual acuity (BCVA) | BCVA using a logMAR visual acuity chart method | baseline to 6 months post-surgery |