Pars Plana Vitrectomy Alone in the Treatment of Macular Schisis in High Myopic Eyes

Study Overview
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Brief Summary
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High myopic schisis (HMF) has the clinical feature of separation between retinal layers. It is sometimes accompanied with foveal retinal detachment, macular lamellar hole, epiretinal membrane and vitreous retraction. HMF may develop to macular hole, macular detachment and will damage the visual function. Pars plana vitrectomy (PPV) is a commonly used surgery in the treatment of HMF. PPV together with internal limiting membrane (ILM) peeling and long-term gas tamponade was reported to be safe and effective. But nowadays there was no available long-term gas in our country. Also, whether ILM peeling is necessary remains controversial, Indole cyanine green (ICG)was proved to have potential toxicity to the retina and the ILM peeling has the risk of causing secondary macular hole. We propose to make a prospective nonrandomized controlled study to evaluate the safety and efficiency of using PPV alone in the treatment of HMF.

Official Title
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Application of Pars Plana Vitrectomy in the Treatment of Macular Schisis in High Myopic Eyes

Conditions
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Retinal Disease, Macular Retinoschisis

Intervention / Treatment
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* Procedure: Pars plana vitrectomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients diagnosed as high myopic macular retinoschisis, with axial length more than 26.5mm. Morphologic manifestation in OCT shows split between retinal layers in macular area. Patients without severe systemic disease and can tolerate surgery. Exclusion Criteria: Patients also have other ocular disease, including glaucoma, keratitis,uveitis, retinal detachment,etc. Patients with nystagmus or have difficult to open the eye. Patients with severe systemic disease and cannot tolerate surgery.
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 |
| --- | --- |
| patients with HMF<br>Patients who are diagnosed as high myopic macular schisis and agree to receive pars plana vitrectomy as the treatment are planned to allocated in this group | Procedure: Pars plana vitrectomy<br>* pars plana vitrectomy without ICG staining and ILM peeling<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The morphologic change of macular area | The thickness of the macular fovea in optical coherence tomography (OCT) | OCT will be done one day before surgery and one week, one month, three months and six months after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The best corrected visual acuity (BCVA) change | The BCVA of all involved patients | One day before surgery and one week, one month, three months and six months after surgery | 
| The best corrected near visual acuity (BCNVA) change | The BCNVA of all involved patients | One day before surgery and one week, one month, three months and six months after surgery | 
| The visual function change | The contrast sensitivity of all involved patients | One day before surgery and one week, one month, three months and six months after surgery |