[Intracorneal selective stromal transplantation]. / Vnutrirogovichnaya transplantatsiya stromy.

Deep anterior lamellar keratoplasty or penetrating keratoplasty are currently considered the optimal methods of surgical treatment of stromal dystrophies and corneal degeneration. Despite certain advantages and benefits of these methods, they also have significant limitations: involvement of superficial corneal layers in the surgery, need for suturing, development of post-keratoplasty astigmatism etc. PURPOSE: This study aimed to test and describe the new method of closed sutureless keratoplasty (intracorneal selective stromal transplantation), which was indicated in isolated dystrophic and degenerative pathology of the stroma. MATERIAL AND METHODS: Intracorneal selective stromal transplantation was performed in a 62-year-old patient with stromal degeneration and intact corneal layers between the altered stroma and the Descemet's membrane posteriorly, and the Bowman's layer anteriorly. The patient also had immature senile cataract. Corneal stroma was removed and replaced with a graft in the optical center of the lens, while the endothelium, the Descemet's membrane and the Bowman's layer remained intact. RESULTS: The proposed technique of intracorneal selective stromal transplantation makes it possible to replace only the pathologically altered stroma through closed surgical approach, without affecting the anterior and posterior surfaces of the cornea. Best-corrected visual acuity has increased in the patient from 0.01 to 0.6, while mean endothelial cell density has not changed in the course of 24-months follow-up. CONCLUSION: The proposed keratoplasty method can be used in patients with dystrophy or degeneration of the corneal stroma and preserved endothelial cells, intact Descemet's membrane and Bowman layer. Since the superficial corneal layers are not involved during the surgery, intracorneal selective stromal transplantation combined the advantages of both deep anterior lamellar keratoplasty and endothelial keratoplasty. The biologically favorable result in this first clinical case allows a preliminary conclusion on the technical possibility and functional effectiveness of the proposed method, but further long-term observation and more clinical cases are required.

[Transplantation of the Bowman's layer in combined treatment of recurrent pterygium]. / Transplantatsiya boumenova sloya v kombinirovannom lechenii retsidiviruyushchego pterigiuma.

Pterygium is among the most frequent indications for extraocular ophthalmic surgery. The main method of pterygium treatment - its excision - is often combined with transplantation, non-transplantation, medication and other methods. However, the frequency of pterygium recurrence can exceed 35%, and the cosmetic and refraction outcomes satisfy neither the patient, nor the surgeon. PURPOSE: The study analyses the technical capability and feasibility for transplantation of the Bowman's layer in the treatment of recurrent pterygium. MATERIAL AND METHODS: The transplantation of the Bowmen's layer was performed according to the developed technique on 7 eyes with recurrent pterygium (7 patients aged 34 to 63 years). The combined surgery technique consisted of pterygium resection, laser ablation, autoconjunctival plasty, exposure to a cytostatic drug, non-suture transplantation of the Bowman's layer. Maximum length of the follow-up was 36 months. Analysis involved data from refractometry, visometry (without correction and with spectacle correction), and optical coherence tomography of the retina. RESULTS: There were no complications in any of the studied cases. The cornea and the transplant retained transparency throughout the entire follow-up duration. 36 months after surgery mean spectacle-corrected visual acuity amounted to 0.86±0.2, topographic astigmatism - 1.48±1.4 diopters. Recurrence of pterygium was not observed. All patients were satisfied with the cosmetic outcomes of the treatment. CONCLUSION: Non-suture transplantation of the Bowmen's layer recovers normal anatomy, physiology and transparency of the cornea after repeat surgical intervention for pterygium. No pterygium recurrences were observed throughout the entire follow-up after treatment with the proposed combined technique.

[On the issue of separate designation of the pre-Descemet's layer in the structure of the cornea]. / K voprosu o vydelenii predestsemetovogo sloya v strukture rogovitsy.

Selective exchange of pathologically altered retinal layers is currently considered the most practical approach in corneal transplantation. Deep anterior lamellar keratoplasty (DALK) and Descemet membrane endothelial keratoplasty (DMEK) are often performed as pathogenetically substantiated transplantation methods. The technique and the course of surgery, possible complications, and achieved outcomes, among other things, depend largely on the pre-Descemet's layer, which was described more than 10 years ago by several ophthalmologists in varying detail. In view of this, the main issue discussed in literature is the following: is the pre-Descemet's layer (Dua's layer) a separate (new) layer of the cornea, or is it an integral part of the stroma (the Feizi stroma)? This article continues the discussion on «separate designation of the pre-Descemet's layer in the structure of the cornea¼ and presents the view of the authors on this problem based on own experience, literature data, anatomical subdisciplines, as well as specific aspects of ophthalmological terminology, and with the use of extrapolation and analogies.

[Descemet membrane endothelial keratoplasty after implantation of glaucoma drainage devices]. / Vozmozhnosti transplantatsii endoteliya s destsemetovoi membranoi posle implantatsii antiglaukomnogo drenazha.

Secondary decompensation of corneal endothelium, including transplanted, is a frequent long-term complication of glaucoma drainage surgery. According to literature data, after implantation of a glaucoma drainage device into the anterior chamber, the speed of endothelial cells density (ECD) loss increases significantly. PURPOSE: To study the possibility of performing modified Descemet membrane endothelial keratoplasty (DMEK) with maximum graft diameter, and to assess its short-term effectiveness in the treatment of bullous keratopathy (BK) in the presence of a glaucoma drainage device in the anterior chamber. MATERIAL AND METHODS: Modified surgery 3/4-DMEK was performed in 9 eyes of 7 patients with BK and Ahmed glaucoma drainage using graft of maximum diameter (11±1 mm). Average follow-up time was 15.3±2.5 months (12 to 18 months). RESULTS: No intraoperative or postoperative complications were observed. Mean ECD after 12 months amounted to 1664±346 cells/mm2, which corresponds to ECD reduction of 34±9.6% (24 to 49%) in comparison to preoperative values. Mean best corrected visual acuity 12 months after surgery increased from 0.04±0.03 (0.01 to 0.1) to 0.3±0.2 (0.04 to 0.7). The last follow-up examination revealed all corneas to have preserved transparency and stable pachymetry measurements (from 488 to 548 µm). CONCLUSION: Performing 3/4-DMEK with a mega graft for treatment of BK after drainage surgery is technically possible. Absence of Descemet membrane (DM) donor and preservation of DM recipient in the drainage tube plane eliminates its contact with the endothelium. Maximum graft diameter should in the long term help prolong the effectiveness of the surgery.