In this limited series, we demonstrate that 1 donor cornea can be successfully used for 5 recipients. Although performing DALK and Q-DMEK on a single day is technically challenging, it is feasible and can dramatically reduce the shortage and the cost of corneal tissue. Strict case selection is necessary. Further study on this approach is required.

Purpose To present a case series of a modified three‐quarter Descemet’s membrane endothelial keratoplasty (3/4‐DMEK) technique to treat pseudophakic bullous keratopathy in the presence of a glaucoma drainage device (GDD) tube in the anterior chamber by reducing the risk of donor endothelial damage due to absence of donor endothelial cells overlying the GGD tube area. Methods In this prospective case series, four eyes of three patients with stable glaucoma underwent 3/4‐DMEK surgery for pseudophakic bullous keratopathy after GDD insertion. The patients were followed up to 24 ± 2.5 months postoperatively. Results No intraoperative or postoperative complications were noted. The average central endothelial cell density (ECD) was 1093 ± 74 cells/mm2 at 12 months postoperatively, corresponding to an ECD decrease of 58 (±6)% as compared to preoperative values. Average best‐corrected visual acuity increased from finger counting before surgery to 20/60 (logMar 0.5) at 12 months after 3/4‐DMEK and remained stable up to 24 months postoperatively. All corneas remained clear at the last available follow‐up. Conclusion This case series demonstrates the technical feasibility of 3/4‐DMEK in eyes with pseudophakic bullous keratopathy in the presence of a GDD tube. The absence of a donor DM and donor cells above the silicone tube excludes direct tube contact with the graft. Longer term studies are needed to show the effect of this modified graft pattern and dimensions on transplant survival.

ä-ð ìåä. íàóê, âåäóùèé íàó÷íûé ñîòðóäíèê îòäåëà òðàâìàòîëîãèè è ðåêîíñòðóêòèâíîé õèðóðãèè Ï.Â. Ìàêàðîâ-ä-ð ìåä. íàóê, âåäóùèé íàó÷íûé ñîòðóäíèê îòäåëà òðàâìàòîëîãèè è ðåêîíñòðóêòèâíîé õèðóðãèè À.À. Ãðäèêàíÿí-àñïèðàíò îòäåëà òðàâìàòîëîãèè è ðåêîíñòðóêòèâíîé õèðóðãèè Â.Ð. Ãåòàäàðÿí-àñïèðàíò îòäåëà òðàâìàòîëîãèè è ðåêîíñòðóêòèâíîé õèðóðãèè

No abstract

The transplantation of Descemet's membrane with endothelium (DMEK) is the most efficient method of treatment of endothelium pathology. However, it is considered that at certain clinical situations DMEK is inappropriate. The purpose of study is to analyze the results of DMEK in complicated clinical situations. Materials and methods. The sampling included 14 patients (16 eyes) with pathology of endothelium of primary (19%) and secondary (81%) genesis and with concomitant alterations, including: total lack of vitreous (19%), non-posterior chamber pseudophakia (25%), presence of Ahmed drainage (25%), artificial lensiris diaphragm (12%), corneal ectasia combined with toric artiphakia (12%), penetrating scar of cornea (6%). Prior to operation, average visual acuity amounted to 0,04±0,05. The subtotal DMEK was applied to 15 eyes and in one case ¼ DMEK was implemented. In 2 cases cornea of donor had keratotomic incisions and in one case Descemetotransplant was formed from residual back layers of cornea after formation of front layer wise transplant using femtosecond laser. The results. No intra-operational complications were established. In 19% of cases a partial mismatch of transplant took place. The repeated DMEK was implemented in 1 case. The recovery of transparency of cornea and increasing of vision acuity were achieved in 94% of cases. In 6 months after operation an average central thickness of cornea amounted to 522±46 μm and density of endothelium cells in average amounted to 1541±486 kl/mm2. Conclusion. The application of DMEK in complicated situations ensures high biological and functional results and is accompanied with minimal number of complications. The procurement of expertise in endothelium surgery, it is appropriate to apply DMEK in all cases of pathology of endothelium.

Lately, layer-wise keratoplasty became the first operation of choice in case of pathology of cornea. In view of satisfying results of endothelial surgery similar operations are implemented at earlier stages that increases need in donor tissue. With increasing of life span of population, also increases number of patients in need of transplantation of cornea. The number of intact cadaver cornea decreases because of stable increase of surgical interventions on front segment of eye. The present article presents original ten years experience concerning optimization of application of donor tissue and indicate on possibilities of further increasing of number of applied keratoplasties. From 2009 to 2015 in the Helmholtz Moscow research institute of eyes diseases 652 transplantations of cornea were implemented in various modifications: straight-through keratoplasty, transplantation of Descemet's membrane with endothelium (DMEK), deep front layer-wise keratoplasty, endokeratoplasty (DSEK) with various modes of transplant formation and 23 frontal layer-wise keratoplasties. In transplantation were also used eyes of donors with radial keratotomy, after laser keratomileusis and with artificial intra-ocular lens. To implement 652 operations 528 cadaver eyes with average age 41 ± 32,5 years (varying from 21 to 87 years) were required. The number of transplantations increased approximately on 50% at potential up to 75%. The lamellar surgery permits using corneal donor tissue with altered frontal surface and to increase number of transplantations of cornea. The renunciation of application of corneal donor tissue with altered frontal surface is inexpedient.

The article presents the results of analysis of loss of density of endothelium cells after endothelium keratoplastry with formation of ultra-thin transplant using femtosecond laser from side of endothelium (UTinvFS-DSEK). The study sampling included 22 patients underwent UTinvFS-DSEK during 2012-2014 in the Helmholtz Moscow research institute of eye diseases. The average time-period of observation made up to 9.6 ± 4.3 months. The Fuchs dystrophy occurred in 31.8%, secondary dystrophy - in 45.4%, inconsistency of endothelium of kerato-transplant - in 22%. All patients were applied photo-registration, visiometry, auto-refractokeratometry, bio-microscopy, tonometry, kerato-analyzing, optical coherent tomography of front segment, confocal microscopy. During the first three years after transplantation, the average loss by endothelium cells made up to 60% of initial level. At that, average loss of density of endothelium cells made up to 1256 ± 450 cells per mm2. In time-periods of six months after surgery the average loss of density of endothelium cells made up to 64% of initial level. The loss of density of endothelium cells remained at the level of 64% after 12 months. In two patients under observation the average density of endothelium cells made up to 996±161 cells per mm 2 after 24 months. The analysis of dynamics of loss by endothelium cells after applied keratoplastry with formation of transplant using femtosecond laser from the side of endothelium demonstrated that received values of loss by cells in existing time-periods exceed, according publications' data, similar indicator after reach-through keratoplastry, standard endokeratoplastry and transplantation of Descemet's membrane with endothelium. The actual study has such certain limitations as average time-periods of observation, limited number of patients, minimal number of patients within time-period more than 24 months.

The DMEK technique is applied five times more rarely than DS(A)EK despite that DMEK provides higher functional result. The main causes are technical "convolution" of implementation, long period of training, accompanied by prolonged operations, higher reject control of donor's tissue, increased rate of dependency of endothelium and mismatch of transplant. Therefore, an efficient technique is needed similar to DMEK though simpler than DMEK.The purpose of study. To analyze the results of implantation of Descemet's transplant (DMET) in patients with endothelium dystrophy of cornea (Fuchs) on the basis of limited clinical observations.Material of study. In two years, DMET was implemented to 12 patients. The study included 6 patients with average age of 60±18 years (from 29 to 80 years). All female patients had primary endothelial dystrophy and one male patient had secondary endothelial dystrophy. The visual acuity prior to DMET in average made up to 0,2±0,2 (from 0,01 to 0,5). The average CTR according optical coherent eye tomography made up to 685±53 µm (from 622 to 749 µm). Results. Within available periods of observation, resorption of edema of cornea takes place in 4 patients (67%) and visual acuity increased from average 0,2±0,1 to 0,45±0,3. In various periods density of endothelium cells varied from 549 to 689 kl per mm2. The indices of optical coherent eye tomography decreased from pre-operational 685±53 µm to 553±15 µm. Conclusion. The results testify efficiency of DMET. The period of restoration of transparency of cornea can vary from 1 to 6 months. The indices of density of endothelium cells are inferior to indices after DMEK. Also, DMET is ineffective in case of secondary dystrophy and at most efficient on previously non-operated eyes.