DSAEK- Postoperative Positioning and Transplant Dislocation

Study Overview
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Brief Summary
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Corneal transplant is a surgical procedure where a damaged or diseased cornea is replaced by donated corneal tissue (the graft) in its entirety (penetrating keratoplasty) or in part (lamellar keratoplasty). One type of lamellar keratoplasty is DSAEK (Descemet's Stripping Automated Endothelial Keratoplasty), where only the damaged posterior section of the cornea is replaced. The purpose of this study is to investigate how immediate postoperative positioning of the patient affects the dislocation rate of the corneal graft. Since this is a new surgical method, little scientific documentation has been published in this area.

Detailed Description
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Corneal transplant is a surgical procedure where a damaged or diseased cornea is replaced by donated corneal tissue (the graft) in its entirety (penetrating keratoplasty) or in part (lamellar keratoplasty). One type of lamellar keratoplasty is DSAEK (Descemet's Stripping Automated Endothelial Keratoplasty), where only the damaged posterior section of the cornea is replaced. To get the graft in the right position inside the eyes anterior chamber, the anterior chamber is fully filled with air, and the patient is placed in a supine position looking facing up for different amount of time depending on the surgeon. In this way the air bubble will press the graft in the right position and prevent dislocation. Our experience is that since the anterior chamber of the eye already is fully filled with air, it does not matter how the patient is positioned postoperatively regarding graft dislocation. Our hypothesis is that the immediate postoperative positioning is insignificant. If this can be significantly proved this may enhance the patients comfort postoperatively.

Official Title
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DSAEK- Postoperative Positioning and Transplant Dislocation

Conditions
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Corneal Transplantation, Descemet Stripping Automated Endothelial Keratoplasty, Fuchs' Endothelial Dystrophy, Corneal Dystrophies, Hereditary

Intervention / Treatment
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* Other: Postoperative positioning: Bed rest
* Other: Postoperative positioning: Sitting up


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Corneal dystrophy requiring corneal transplantation Patients written permission Pseudophakia Exclusion Criteria: Uncontrolled glaucoma Phakia or aphakia Shallow anterior chamber Fibrotic cornea Demented patients Claustrophobic patients Patients that do not want to participate

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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Postoperative positioning: Bed rest<br>Patients in this group must be lying down facing up 2 hours postoperatively | Other: Postoperative positioning: Bed rest<br>* Patients in this group should be lying down facing up 2 hours postoperatively<br>|
| Other: Postoperative positioning: Sitting up<br>Patients in this group should be sitting up in a chair 2 hours postoperatively | Other: Postoperative positioning: Sitting up<br>* Patients in this group should be sitting up in a chair 2 hours postoperative<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Graft dislocation measured by slit lamp examination | Graft dislocation is checked 2 hours postoperatively, they day after the surgery, 1 week after, 1 month, and then every 3. month for 1 year, and then every 6. months for 5 years. | 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraocular pressure (IOP) | The intraocular pressure (IOP) is measured at every postoperative control | 5 years | 
| Visual Acuity | Visual Acuity is measured at every postoperative control | 5 years | 
| Endothelial cell count of the graft | Endothelial cell count of the graft is measured at every postoperative control | 5 years |