Safety and Feasibility of Sutureless Pars-plana Vitrectomy in Sub-Tenon Anesthesia

Study Overview
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Brief Summary
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The aim of this prospective study is to investigate the feasibility of performing minimally invasive vitrectomy under sub-tenon anesthesia in terms of intraoperative patients' tolerance and the surgeon's confidence. In particular, the tolerance and pain sensation during the operation as well as the possible perception of light and colour sensations are to be recorded with the help of questionnaires. In addition, the surgeon's impressions regarding eye motility, chemosis and general feasibility will be evaluated.

Detailed Description
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A prospective, one-center clinical trial to identify the safety and feasibility of sutureless pars-plana vitrectomy performed in sub-tenon anesthesia. Background: In Germany pars-plana vitrectomies are mostly performed in general anesthesia. This requires the immediate availability of a trained anesthesiology team, which is not always granted, especially in urgent eye disease (i.e. endophthalmitis, high risk retinal detachment). Furthermore, some patients are not suitable for general anesthesia due to systemic diseases (i.e. cardio-vascular diseases). There are several procedures of local ocular anesthesia (i.e. peribulbar, retrobulbar, sub-tenon anesthesia). The main advantage of sub-tenon anesthesia is the use of a blunt cannula limiting the risk of potential complications. Purpose: The purpose of this study is to investigate the safety of local sub-tenon anesthesia procedure for sutureless vitrectomy (anesthetic mixture: 2ml xylocaine and 2ml bupivacaine) in a prospective clinical study design. Objectives: Primary outcome: The evaluation of 1. sensation of pain, 2. patients' intraoperative discomfort and 3. visual sensations using the standardized questionnaires (WONG-BAKER Faces Scale, Visual Analog Scale and individual questions). Secondary Outcome: The evaluation of 1. chemosis, 2. eye movement, 3. surgeon's general feeling of comfort during surgery (rating scale).

Official Title
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A Prospective, One-center Clinical Trial to Identify the Safety and Feasibility of Sutureless Pars-plana Vitrectomy Performed in Sub-tenon Anesthesia.

Conditions
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Vitreoretinal Diseases

Intervention / Treatment
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* Procedure: minimally invasive vitrectomy under subtenon anaesthesia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age over 40 years Presence of a clinical condition that requires surgical treatment with vitrectomy and does not necessarily require general anesthesia (retinal detachment, endophthalmitis, vitreous hemorrhage, after silicone oil surgery, vitreomacular traction, epiretinal gliosis, macular holes, subretinal bleeding, lens luxation). The medical indication for vitrectomy is not linked to study participation. Not until the patient has consented to the vitrectomy (standardized information forms) potential study subjects will be approached to participate in the clinical trial. Willingness to participate in the clinical trial Understanding the objectives of the clinical trial and the study process Signed informed consent form Exclusion Criteria: Concomitant diseases of the eye State after filtering glaucoma operations Distinct corneal opacities, which make the examination considerably more difficult Complicated proliferative vitreoretinopathy Lack of understanding of the study, its objectives and study conduct Psychiatric diseases Pregnancy Simultaneous participation in another clinical trial

Ages Eligible for Study
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Minimum Age: 40 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| minimally invasive vitrectomy under subtenon anaesthesia<br> | Procedure: minimally invasive vitrectomy under subtenon anaesthesia<br>* The safety and feasibility in terms of tolerance and pain sensation during the surgery as well as the possible perception of light and colour sensations in minimally invasive vitrectomy under sub-tenon anesthesia shall be investigated.<br>|
| minimally invasive vitrectomy under general anaesthesia<br> | Procedure: minimally invasive vitrectomy under subtenon anaesthesia<br>* The safety and feasibility in terms of tolerance and pain sensation during the surgery as well as the possible perception of light and colour sensations in minimally invasive vitrectomy under sub-tenon anesthesia shall be investigated.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensation of pain | 11-point numeric scale ranges from '0' (means no pain) to '10' (means worst pain imaginable), Questionnaire Wong-Baker FACES® Scale (6 Faces, range no hurt - hurts worst), Questionnaire | 1 Day | 
| Discomfort | 11-point numeric scale ranges from '0' (means no discomfort) to '10' (means worst discomfort imaginable), Questionnaire | 1 Day | 
| Visual Sensations | 4 questions, Likert scale (yes, no, don't know/not sure), Questionnaire perception of details during surgery (instruments, surgeon's face) perception of colors during surgery perception of lights or shadows no light perception at all during surgery | 1 Day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Chemosis | 5-point numeric scale from '0' (means no chemosis) to 4 (means chemosis of all 4 eye quadrants), Questionnaire (surgeon) | 1 Day | 
| Eye movement | 4-point numeric scale: '0' (means ptosis and no motility), '1' (mild motility), '2' (moderate motility), '3' (full motility), Questionnaire (surgeon) | 1 Day | 
| Surgeon's general feeling of comfort during the surgery | 6-point numeric scale ranges from '1' (means best comfort conditions) to '6' (means worst comfort conditions) Questionnaire (surgeon) | 1 Day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Sub-tenon Anesthesia, Vitrectomy, Sutureless vitrectomy