Silicone Oil Tamponade for Vitrectomy of Hypermyopic Foveoschisis.

Study Overview
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Brief Summary
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The purpose of this study is to explore the efficiency and safety of the surgical procedure of pars plana vitrectomy with silicone oil tamponade and without internal limiting membrane peeling for myopic foveoschisis eyes with high risk of macular hole formation.

Official Title
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A Prospective, Randomized, Controlled, Multicentered Study of Vitrectomy With Silicone Oil Tamponade for Hypermyopic Foveoschisis.

Conditions
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Hypermyopic Foveoschisis

Intervention / Treatment
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* Procedure: PPV with SO tamponade
* Procedure: PPV with fovea-sparing ILMP and gas tamponade
* Procedure: PPV with gas tamponade


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with spherical ≥ -8 diopters or axial length ≥ 26.5mm. The foveoshisis combined with foveal detachment was showed on the OCT image. The foveal detachment height≥ 250 um ,and the thickness of sensory retina of foveal detachment was ≤100 um; patients signed the ICF. patients with BCVA ≤0.5,and with visual disturbance symptoms. Exclusion Criteria: patients with macular hole accompanied or secondary of other fundus disease received vitrectomy due to other diseases glaucoma cannot be controled by medication patients with other retinal or choroidal disease that may affect VA poor patients compliance poor condition that cannot undertake the surgery optical opacities which make it difficult to exam fundus or measure on OCT

Ages Eligible for Study
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Minimum Age: 18 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: Silicone oil group<br>Patients randomized into this group were received pars plana vitrectomy surgery with silicone oil tamponade and without internal limiting membrane peeling. And silicone oil tamponade was removed at least 12 months after the primary surgery with completely resolved of foveoschisis. | Procedure: PPV with SO tamponade<br>* Patients randomized into silicone oil group were received pars plana vitrectomy surgery with silicone oil tamponade and without internal limiting membrane peeling. And silicone oil tamponade was removed at least 12 months after the primary surgery with completely resolved of foveoschisis.<br>|
| Active Comparator: Gas group 1<br>Patients randomized into this group were received pars plana vitrectomy surgery with fovea-sparing internal limiting membrane peeling and gas tamponade. | Procedure: PPV with fovea-sparing ILMP and gas tamponade<br>* Patients randomized into gas group 1 were received pars plana vitrectomy surgery with fovea-sparing internal limiting membrane peeling and gas tamponade.<br>|
| Active Comparator: Gas group 2<br>Patients randomized into this group were received pars plana vitrectomy surgery with gas tamponade and without internal limiting membrane peeling. | Procedure: PPV with gas tamponade<br>* Patients randomized into gas group 2 were received pars plana vitrectomy surgery without internal limiting membrane peeling and gas tamponade.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Complete resolved rate of foveoschisis observed on OCT image. | The compete resolved of foveoschisis was evaluated using OCT image. | 18 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Best corrected visual acuity (BCVA) change compared with baseline BCVA. | Best corrected visual acuity (BCVA) change compared with baseline BCVA by ETDRS chart. | 18 months | 
| The posoperative macular hole formation rate. | The posoperative macular hole formation rate of different groups | 18 months |