DMEK Endothelial Keratoplasty in Patients With a History of Anterior or Posterior Segment Surgery

Study Overview
=================
Brief Summary
-----------------
DMEK (Descemet Membrane Endothelial Keratoplasty) is a surgical technique used to treat primary or secondary corneal endothelial decompensation. At the Rothschild Foundation, as in many Western referral centers, DMEK is currently the surgical technique of choice for the treatment of primary or secondary corneal endothelial decompensation. Technically challenging, it is a relatively tedious surgery to learn, but offers the best visual and refractive results, as well as faster visual and functional recovery in simple cases. In patients without anterior or posterior segment surgical history, the complication rate of DMEK, including graft rejection, is similar to that of other endothelial keratoplasty surgical techniques. However, in specific cases, in patients with a history of ophthalmological surgery such as vitrectomy, trabeculectomy, large iris defects, anterior synechiae, aniridia or aphakia, the scientific literature shows a higher complication rate for DMEK (increased rate of rebulling and graft decompensation). As a result, other techniques that are less effective on visual results continue to be used for these patients in a large number of centers. Nonetheless, in our department, DMEK is also performed on these complicated patients. When it comes to patients with a history of anterior or posterior segment surgery, it seems to us that the surgeons' experience with DMEK allows better visual results than with any other technique, but without any back up regarding the complication rate in the literature. The main aim of this study is to describe, in patients with a history of anterior or posterior segment surgery undergoing DMEK, the 12-months occurrence rate of at least one serious post-operative complication.

Official Title
-----------------
DMEK Endothelial Keratoplasty in Patients With a History of Anterior or Posterior Segment Surgery : Serious Complication Rate and Visual Efficacy at 12 Months

Conditions
-----------------
Patients Undergoing DMEK With a History of Anterior or Posterior Segment Surgery

Intervention / Treatment
-----------------
* Procedure: Descemet Membrane Endothelial Keratoplasty


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria : Patients scheduled for corneal endothelial transplantation in one or both eyes History of vitrectomy, trabeculectomy, large iris defects, anterior synechiae on the eye to be operated on Pseudophakia or aphakia in the eye to be operated on Express consent to participate in the study Affiliated or beneficiary of a social security scheme Exclusion Criteria : Need for combined PKE + EK surgery Primary endothelial decompensation At least one contraindication to endothelial transplantation : Presence of a stromal corneal cleft Inflammatory or degenerative corneal pathology other than endothelial Progressive corneal infection Degenerative retinal pathology not allowing visual recovery postoperatively (for the purposes of this study, we accept patients who have had retinal detachment and whose loss of vision is clearly attributable to endothelial decompensation) End-stage glaucoma not allowing visual recovery post-operatively (for this study, we accept patients who have had filtering surgery for glaucoma, which is stabilized at the time of surgery. Decline in vision must be clearly attributable to endothelial decompensation) Personal history of corneal transplantation on the eye to be operated on Medical contraindication to general or local anesthesia Patient under legal protection Pregnant or breast-feeding women

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Intervention/Treatment |
| --- |
|Procedure: Descemet Membrane Endothelial Keratoplasty|DMEK (Descemet Membrane Endothelial Keratoplasty) is a surgical technique used to treat primary or secondary corneal endothelial decompensation.|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence rate of at least one serious DMEK post-op complication | Composite endpoint made of 4 serious post-op complications : Rebulling : graft detachment of more than one-third of its surface area one week after surgery (on Avanti OCT-cornea), requiring air or gas injection in the anterior chamber. Graft failure : no improvement in pachymetry at three months post-op (Avanti OCT-cornea). Graft rejection : presence of cellular Tyndall in the anterior chamber and/or retro-descemetic precipitates and/or focal or diffuse increase in pachymetry > 20μm (Avanti OCT-cornea and slit-lamp biomicroscopic examination). Macular cystoid edema : presence of intraretinal fluid in the macular area (macular OCT). | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rebulling occurrence rate | Graft detachment of more than one-third of its surface area one week after surgery (on Avanti OCT-cornea), requiring air or gas injection in the anterior chamber. | 12 months | 
| Graft failure occurrence rate | No improvement in pachymetry at three months post-op (Avanti OCT-cornea). | 12 months | 
| Graft rejection occurrence rate | Presence of cellular Tyndall in the anterior chamber and/or retro-descemetic precipitates and/or focal or diffuse increase in pachymetry > 20μm (Avanti OCT-cornea and slit-lamp biomicroscopic examination). | 12 months | 
| Macular cystoid edema occurrence rate | Presence of intraretinal fluid in the macular area (macular OCT). | 12 months | 
| Intraocular hypertension occurrence rate | Intraocular pressure greater than 21mmHg measured by pneumotonometer or applanation tonometer. | 12 months | 
| Graft detachment (with or without rebulling) occurrence rate | Failure of the graft to press against the posterior host corneal stroma (Avanti OCT-cornea and slit-lamp biomicroscopic examination). | 12 months | 
| Surgeon's subjective assessment of surgical complexity | Evaluation by the main surgeon at the end of the procedure, on a Likert scale from 0 to 10 (0 being normal, uncomplicated surgery and 10 being the maximum level of complexity encountered). | Right after the completion of the surgery | 
| Duration of surgical procedure (in minutes) | The start of the procedure is defined by the placement of the blepharostat and the end of the procedure is defined by the end of the lens dressing. | Right after the completion of the surgery | 
| Evolution of visual results (corrected and uncorrected) | Measurements with optotypes : Best monocular visual acuity (decimal scale converted to logMAR) | 1 month after surgery | 
| Evolution of visual results (corrected and uncorrected) | Measurements with optotypes : Best monocular visual acuity (decimal scale converted to logMAR) | 3 months after surgery | 
| Evolution of visual results (corrected and uncorrected) | Measurements with optotypes : Best monocular visual acuity (decimal scale converted to logMAR) | 6 months after surgery | 
| Evolution of visual results (corrected and uncorrected) | Measurements with optotypes : Best monocular visual acuity (decimal scale converted to logMAR) | 12 months after surgery | 
| Evolution of refractive results | Nidek® autorefractometer measurement : Sphere (in dioptres) Cylinder (in dioptres) Spherical equivalent (in dioptres) Cylinder axis (in degrees) | 1 month after surgery | 
| Evolution of refractive results | Nidek® autorefractometer measurement : Sphere (in dioptres) Cylinder (in dioptres) Spherical equivalent (in dioptres) Cylinder axis (in degrees) | 3 months after surgery | 
| Evolution of refractive results | Nidek® autorefractometer measurement : Sphere (in dioptres) Cylinder (in dioptres) Spherical equivalent (in dioptres) Cylinder axis (in degrees) | 6 months after surgery | 
| Evolution of refractive results | Nidek® autorefractometer measurement : Sphere (in dioptres) Cylinder (in dioptres) Spherical equivalent (in dioptres) Cylinder axis (in degrees) | 12 months after surgery | 
| Evolution of endothelial loss | Measurement by central and peripheral specular microscopy (4 measurements performed nasally, temporally, superiorly and inferiorly). Endothelial loss in each quadrant is defined as a decrease in endothelial count (cells/mm²) expressed as a % relative to the pre-operative measurement. | 1 month after surgery | 
| Evolution of endothelial loss | Measurement by central and peripheral specular microscopy (4 measurements performed nasally, temporally, superiorly and inferiorly). Endothelial loss in each quadrant is defined as a decrease in endothelial count (cells/mm²) expressed as a % relative to the pre-operative measurement. | 3 months after surgery | 
| Evolution of endothelial loss | Measurement by central and peripheral specular microscopy (4 measurements performed nasally, temporally, superiorly and inferiorly). Endothelial loss in each quadrant is defined as a decrease in endothelial count (cells/mm²) expressed as a % relative to the pre-operative measurement. | 6 months after surgery | 
| Evolution of endothelial loss | Measurement by central and peripheral specular microscopy (4 measurements performed nasally, temporally, superiorly and inferiorly). Endothelial loss in each quadrant is defined as a decrease in endothelial count (cells/mm²) expressed as a % relative to the pre-operative measurement. | 12 months after surgery | 
| Evolution of corneal thickness | Corneal thickness in μm measured by OCT - Avanti® type cornea. | 1 month after surgery | 
| Evolution of corneal thickness | Corneal thickness in μm measured by OCT - Avanti® type cornea. | 3 months after surgery | 
| Evolution of corneal thickness | Corneal thickness in μm measured by OCT - Avanti® type cornea. | 6 months after surgery | 
| Evolution of corneal thickness | Corneal thickness in μm measured by OCT - Avanti® type cornea. | 12 months after surgery | 
| Evolution of posterior keratometry | Posterior keratometry in diopters measured by Scheimpflug corneal topography (Pentacam®). | 1 month after surgery | 
| Evolution of posterior keratometry | Posterior keratometry in diopters measured by Scheimpflug corneal topography (Pentacam®). | 3 months after surgery | 
| Evolution of posterior keratometry | Posterior keratometry in diopters measured by Scheimpflug corneal topography (Pentacam®). | 6 months after surgery | 
| Evolution of posterior keratometry | Posterior keratometry in diopters measured by Scheimpflug corneal topography (Pentacam®). | 12 months after surgery |