Dmek In Cases With Subepithelial Fibrosis: A Good Alternative To Penetrating Keratoplasty

Fuchs Endothelial Corneal Dystrophy (FECD) and pseudophakic bullous keratopathy remain as main causes for keratoplasty procedures. Decreasing endothelial cell count leads to corneal edema, triggers stromal keratocyte apoptosis and subsequently subepithelial fibrosis in advanced cases. Traditionally, penetrating keratoplasty (PK) has been the surgery of choice for cases featuring subepithelial fibrosis. However, alternative options like Descemet's Membrane Endothelial Keratoplasty (DMEK) with manual or phototherapeutic keratectomy in a secondary procedure have also been explored. Nevertheless, we present a case series where DMEK alone has led to partial or total improvement of subepithelial fibrosis without the need for additional surgeries.

Fundación de Oftalmología Médica de la Comunidad Valenciana (FOM), Valencia, Spain. Cornea Unit.

We present 13 cases with different grades of subepithelial fibrosis in which DMEK was performed and evaluated postoperative improvement in vision and corneal clearance. The primary cause in 10 cases was FECD and 3 cases pseudophakic bullous keratopathy. The fibrosis was centrally located in 8 cases, paracentrally in 3 cases, and in both locations in 2 cases. All patients underwent uncomplicated DMEK. Epithelium was debrided during the surgery  in 8 out of the 13 cases, mainly to enhance visualization during surgery, but we also explored whether there was any correlation with fibrosis resolution.

We observed improvement of subepithelial fibrosis in 77,5% of the cases (partial resolution in 61.5% of cases and a total resolution in 38.5% of cases). There were no differences in fibrosis resolution whether the epithelium was debrided or not (37,5% vs 40%). Vision improved in all eyes after DMEK. The mean increase in best-corrected visual acuity (BCVA) was 0.43 (range 0,25 to 0,97). Upon further analysis, when dividing the sample into two groups based on whether epithelium was removed or not, the results showed an increase of 0.43 for de-epithelized cases and 0.46 for non-de-epithelized cases. It's worth noting that these data may be influenced by other concurrent visual impairments such as lens calcification or glaucoma in two eyes.

Subepithelial fibrosis improves after DMEK, being DMEK a viable alternative and a safer option compared to PK in these cases. Despite partial resolution of the fibrosis, vision improved considerably in all of our patients. Epithelial debridement doesn´t seem to influence on fibrosis or visual improvement, although studies with a larger sample should be performed. a. Additionally, we suggest evaluating the depth of the fibrosis using AS-OCT in each case to determine the possibility of improvement and most appropriate therapeutic approach.