Lamellar Keratoplasty Techniques Research Articles

Donor Characteristics in Graft Detachment after Posterior Lamellar Keratoplasty for Fuchs Endothelial Dystrophy and Bullous Keratopathy.

Background: Descemet Membrane Endothelial Keratoplasty (DMEK) has been widely adopted to treat Fuchs endothelial dystrophy (FED) and Bullous keratopathy (BK). Graft detachment (GD) is one of the common earliest post-operatory complications, and it is usually recovered by Air Rebubbling (ARB). Methods: Retrospectively, we investigated predictive factors related to GD between January 2016 and March 2020, a pre-COVID era, in 72 patients, 72 eyes, and their donors' lamellar characteristics, focusing on donor's cause of death. The patients were divided according to the posterior lamellar keratoplasty technique adopted. Results: GD and consequent ARB were most common but not significantly prevalent in DMEK (p = 0.11). It was more common in FED for both surgical approaches. Only in BK treated with DSAEK were host steeper mean astigmatism (p = 0.03) and donors with smaller graft pre-cut diameters (p = 0.02) less likely to be related to GD. Regarding donor's cause of death, only cardiovascular accident could be related to GD in BK treated with DMEK (p = 0.04). Conclusions: Our study shows that the conventional match between pathology and corneal lenticule is not sufficient to prevent ARB. Donor's cause of death can impair graft and host attachment. In particular, cardiovascular death may impair the efficiency of donors' endothelial cells, inducing GD after DMEK in BK.

Retrospective Analysis of a New Intrastromal Dissection Technique Using the Retinal Reflex for Deep Anterior Lamellar Keratoplasty.

The purpose of this study was to describe a new surgical technique for deep anterior lamellar keratoplasty. All pupils in the recipient eyes were dilated preoperatively. Vertical grooving was performed using a crescent blade with a width of 5 mm and a depth of one-third to half corneal thickness on the temporal side of the limbus. Stromal dissection was performed as close as possible to Descemet membrane by observing the gap between the gold line by retinal reflex and the front edge of the crescent blade. Lamellar dissection was performed along the lamellar plane using corneal dissectors. The ophthalmic viscoelastic device was injected into the intrastromal pocket to separate the anterior and posterior stroma and an anterior corneal lamella was excised. A donor cornea was sutured into the recipient bed. In 18 eyes, none of the patients had Descemet membrane rupture during surgery. The mean postoperative residual stromal thickness was 80 ± 31 μm. The mean central corneal thickness after surgery was 660 ± 69 μm. At the last follow-up, the cornea was cleared in all 18 eyes on slit-lamp examination. We estimated the residual stromal thickness based on the gap between the gold line by the retinal reflex and crescent blade, and intrastromal lamellar dissection was performed using a smooth corneal dissector. Consequently, the surface of stromal dissection was smooth, and the residual stromal thickness was even.

Trends in keratoplasty from central and Northern India. Part I: Indications for keratoplasty.

To report the indications for keratoplasty and analyze trends in two decades in India. This was a retrospective review of eye bank registries of six tertiary eye care centers located in central and northern India from 2005 to 2021. The patterns of corneal pathology and changes in trends were analyzed. Between 2005 and 2021, 13223 corneal grafts were performed in the six collaborating tertiary eye care centers. The most common indication for keratoplasty in both decades was corneal ulcer (41.1%), followed by corneal scar (25.5%), failed graft (12.0%), post-cataract surgery corneal edema (11.7%), corneal dystrophies (3.1%), corneal ectasia (1.8%), corneal trauma (0.3%), congenital corneal opacity (0.3%), and others (4.1%). An increasing trend was seen in corneal ulcers, failed grafts, and keratoconus. A reducing trend was seen in corneal scar and aphakic bullous keratopathy. There was no change in pseudophakic bullous keratopathy and Fuchs endothelial corneal dystrophy. Corneal ulcers, corneal scars, failed grafts, and post-cataract surgery corneal edema remained the foremost indications for keratoplasty in two decades in India. An increasing trend was seen in corneal ulcers and failed grafts which are of concern as these indications carry a poorer outcome. Capacity building in lamellar keratoplasty techniques is the need of the hour as pseudophakic bullous keratopathy was an important indication, and an increasing trend was noticed in keratoconus.

Ex vivo demonstration of canine corneal pre-Descemet’s anatomy using pneumodissection as for the big bubble technique for deep anterior lamellar keratoplasty

The recent discovery and characterization of pre-Descemet’s layer (PDL; also termed the Dua’s layer or the Dua-Fine layer) has advanced the understanding of various posterior corneal pathologies and surgeries in human. This study aimed to characterize the ultrastructure of the posterior stroma and interfacial zone of Descemet’s membrane (DM) in canine eyes. Eighteen canine corneo-scleral discs were included. Intrastromal air injection resulted in the formation of type 1 big bubble (BB) in 73% (n = 11/15) of corneas, with a mean diameter of 11.0 ± 1.3 mm. No type 2 BB was created. Anterior segment optical coherence tomography, histology and transmission electron microscopy confirmed that the wall of BB was composed of DM, in contact with remaining stroma (canine PDL; cPDL). The cPDL was populated with keratocytes, of varying thickness of 16.2 ± 4.2 µm in close apposition to the DM, and composed of collagen bundles arranged in transverse, longitudinal and oblique directions. The interfacial zone, between DM and cPDL, showed fibril extension in all three directions, predominantly longitudinal. Irregular extensions of DM material into cPDL stroma were observed. No long-spaced collagen was detected. In conclusion, there exists a well-defined cleavage plane between the posterior stroma and cPDL, with similar but not identical characteristics as in humans, that is revealed by pneumodissection. This adds to our understanding of the anatomy of the posterior most canine cornea, which will have significant clinical impact on posterior corneal surgery and understanding of corneal pathology in dogs.

Large-Diameter Modified Big-Bubble Deep Anterior Lamellar Keratoplasty in Post–Radial Keratotomy Eyes

To report the outcomes of our modified large-diameter (9 mm) big-bubble deep anterior lamellar keratoplasty (DALK) technique with improved success rates of pneumatic dissection in post-radial keratotomy (RK) eyes. Ospedali Privati Forlì, "Villa Igea", Forlì, Italy. Retrospective case series. Modified big-bubble DALK was performed in consecutive post-RK eyes. The technique included large diameter (9-mm) diameter deep partial thickness trephination based on the thinnest anterior segment optical coherence tomography pachymetry value at 9 mm; air injection through a cannula advanced 2 mm centripetally from the base of the trephination; limited stromal clearance of the central 6 mm optical zone; suturing of a 9-mm anterior lamellar graft prepared by microkeratome dissection. Success rate of pneumatic dissection, corrected distance visual acuity (CDVA), keratometric astigmatism and complications were recorded. 8 eyes of 7 patients were included. Pneumatic dissection succeeded in 7 cases (87.5%). CDVA significantly improved from 0.94 ± 0.43 to 0.14 ± 0.06 logMAR (P <.001). All eyes reached Snellen CDVA ≥ 20/40, while 3 eyes (37.5%) reached ≥ 20/25. At the last follow-up, 5 eyes (62.5%) had a final keratometric astigmatism ≤4 D, while 2 eyes (25.0%) had ≤ 2 D. Big-bubble DALK can be successfully performed in post-RK eyes with our standardized technique.

Keratoconus: Past, present and future

AbstractAlthough corneal ectasias had been observed since antiquity and keratoconus eventually became a major indication for keratoplasty in the XX century, only after the introduction of corneal topography it was realized that its actual frequency (of a certain degree of) was much higher than previously suspected. Today keratoconus is recognized as a one of the major corneal degenerative diseases, with both familial (genetic) and environmental influences. It is one of the leading causes of corneal visual deficit, affecting significant portions of the population in multiple regions of the world. In the last decades, we have witnessed a revolution in this field, with increasingly sensitive and specific methods for its detection, as well as a wide spectrum of conservative management options ‐from corneal collagen crosslinking and topography‐guided laser corneal ablation to intracorneal ring segment implants and phakic intraocular lenses. While this has resulted in a reduction of the eyes requiring a corneal transplant, these have also become safer and more selective with the development of deep anterior lamellar keratoplasty techniques. This presentation will review the evolution of the keratoconus and other corneal ectasia, from the concept to the recent progresses and what can be expected in the future regarding their diagnosis and management.

Modified Deep Anterior Lamellar Keratoplasty Technique to Rescue Failed Penetrating Keratoplasty.

To describe a modified deep anterior lamellar keratoplasty (DALK) technique to rescue failed penetrating keratoplasty (PK) grafts and report its results. Retrospective, case-series analysis of patients who underwent modified DALK to rescue failed corneal grafts after PK was included. Every patient had corneal graft failure (GF) diagnosis due to anterior corneal (epithelium, Bowman's, and stroma layers) or refraction disorders uncorrectable with conservative management. The main objective of the surgery and primary outcome of the study was the improvement of corrected distance visual acuity (CDVA). The study's secondary outcome was the frequency of intra- and postoperative complications. This series included four eyes from three patients with a mean age of 57.7 years (range: 51-63 years). Mean follow-up of patients was thirteen months (range: 12-15 months). During follow-up, continuous improvement of corneal transparency and CDVA was observed in every patient. The only intraoperative complication reported was a peripheric DM microperforations of previous graft-host junction in two eyes. No signs of double anterior chamber, endothelial failure, GF, glaucoma, or other side effects were reported. Our results suggest that modified DALK in patients with GF after PK, preserving a healthy endothelium, is surgically feasible. However, further studies are needed to compare this procedure to PK and other DALK technique variations.

Rediscovering a valuable manual Deep Anterior Lamellar Keratoplasty (DALK) technique: Outcomes of 42 "Peeling-off" DALK.

Residual bed thickness in DALK should be less than 80μm to provide optimal visual outcomes. "Peeling-off" is a manual DALK technique, which separates the anterior stroma by pulling the deep stromal lamellae following the plane of their lowest adhesion, which is usually very deep. The purpose of this study is to measure the residual bed thickness achievable with this technique. Retrospective case series of "Peeling-off" DALK cases performed between January 2014 and January 2021 with at least 1 year of follow-up. Indications for DALK, intraoperative and postoperative complications, residual recipient bed thickness at 1 day and at 1 month after surgery, and postoperative best corrected visual acuity (BCVA) at 1 year of follow up were evaluated. 42 eyes (42 patients) underwent DALK performed with "Peeling-off" technique. Indications for surgery were keratoconus in 33 eyes and stromal scar in 9 eyes. "Peeling-off" technique was used as a rescue approach to perform a DALK after a failed Big-Bubble in all cases, and also failed Air-Visco-Bubble in some cases. No intraoperative and postoperative complications were recorded. Residual recipient bed thickness was deep and regular, measuring 42 microns at 1 day postoperative (range 21-65 microns) and 23 microns (range 17-26 microns) at 1 month postoperative. Mean postoperative BCVA at 1 year of follow up was 0.18 logMAR ± 0.09. "Peeling-off" DALK is a valuable manual technique that achieves a deep stromal plane with optimal visual outcomes.

Pre-Descemet’s Endothelial Keratoplasty (PDEK), Complicated by Dislocation of the IOL into the Vitreous. Case Report

This paper presents a case report of Pre-descemet’s endothelial keratoplasty (PDEK) performed on a 72-year-old patient diagnosed with bullous keratopathy, artiphakia, operated open-angle IIIА glaucoma. PDEK is a method of endothelial keratoplasty in which the non-functioning endothelial layer with Descemet’s membrane is replaced with a donor material consisting of Dua’s layer, Descemet’s membrane and endothelium. In the early postoperative period the IOL dislocated into the vitreous body. Both the technique of posterior lamellar keratoplasty and the surgical tactics that were successfully applied in this situation are described in detail. Clinical and functional results were studied with a follow-up period of 6 months.

Modified big bubble technique for deep anterior lamellar keratoplasty in keratoconus.

We describe a modified technique for deep anterior lamellar keratoplasty with three modifications in big bubble pneumodissection technique; including two staged stromal trephination to avoid inadvertent full-thickness trephination, deep bevel-up needle air injection for better visualization and deeper air injection and, vicoseperation by refilling the pre-Descemet space with a viscoelastic after removing the air bubble for safe removal of the deep stromal layers. Patients with advanced keratoconus underwent deep anterior lamellar keratoplasty with pneumodissection by two-staged trephination followed by bevel-up needle deep air injection and viscoseperation. The big bubble was successfully formed in all cases and there was no case with the rupture of the Descemet's membrane (DM) during air injection or baring of DM.

"Groove and Peel" Deep Anterior Lamellar Keratoplasty: How Deep Can You Go?

The aim of the current research was to measure the thickness of the residual central corneal bed after performing the manual "Groove and Peel" deep anterior lamellar keratoplasty (GP-DALK) technique on human cadaveric eyes. The manual GP-DALK technique was performed on 6 human cadaver eyes by an experienced corneal surgeon. After surgery, the eye globes were fixed in 10% buffered formalin and embedded in paraffin. For each eye, 4-μm-thick hematoxylin and eosin sections involving the pupillary axis were obtained and examined. Using an image-processing software, 2 observers measured the corneal thickness of the residual central corneal bed and the peripheral corneal rims. The overall mean central corneal bed thickness was 35.5 ± 12.9 μm, whereas the mean right and left peripheral rim thicknesses were 993.0 ± 141.1 and 989.3 ± 147.1 μm, respectively ( P = 0.0006 ). In most corneas, the level of dissection reached almost to the pre-Descemetic collagen (Dua) layer. The GP-DALK technique is effective in removing most of the corneal stroma and may be non-inferior to "big-bubble" deep anterior lamellar keratoplasty in some cases.

10-year experience with lamellar keratoplasty for the surgical Management of Paediatric Corneal Diseases.

To evaluate the outcomes of various lamellar keratoplasty techniques performed at our Institution in children aged 14 years or younger over the last decade. This single-centre study reviewed 72 eyes that underwent lamellar keratoplasty for various indications. Deep anterior lamellar keratoplasty (DALK) was performed in 19 eyes, mushroom penetrating keratoplasty (PK) in 27 eyes and Descemet stripping automated endothelial keratoplasty (DSAEK) in 25 eyes. The main outcome measures included best spectacle-corrected visual acuity (BSCVA), complications and rate of graft failure which was defined as any graft requiring repeat transplantation. Best spectacle-corrected visual acuity (BSCVA) significantly improved after DALK, mushroom PK and DSAEK (all p < 0.05), with 50%, 60% and 56% of eyes reaching ≥20/40, respectively. Stromal rejection was observed in 1 eye (5.3%) after DALK, whilst endothelial rejection occurred in 1 eye after mushroom PK (3.7%) and 1 eye after DSAEK (4.0%). Overall survival was 100% after DALK (mean follow-up: 23.0 months), 92.8% after mushroom PK (mean follow-up: 42.3 months) and 96.0% after DSAEK (mean follow-up: 33.6 months). Deep anterior lamellar keratoplasty (DALK), mushroom PK and DSAEK offer good visual outcomes for children with corneal pathology, with low rates of immunological rejection and graft failure.

Corneal Stromal Abscess in a Dog

ABSTRACTBackground: The eye is an important sense organ responsible for sight. The cornea is the outermost of many eye layers, being predisposed to several lesions, some of them being frequent in small animal clinics meanwhile others are unusual and seldom reported in specialized literature. The stroma abscess is a common condition in horses, but atypical in dogs, it's a condition in which a microperforation in the corneal epithelium allows microorganisms or a foreign body to penetrate the corneal stroma, and those become inside the cornea after a re-epithelialization, producing an intense inflammatory response. Therefore, this case reports a case of deep stromal abscess in a Shih Tzu dog.Case: A 4-year-old female Shih Tzu, weighing 4.6 kg, was submitted to ophthalmic examination in which the left eye presented an opaque yellowish-white protruding structure located on the right side, in the center of the cornea (3 o´clock position), bulbar and palpebral conjunctival hyperemia and congestion, chemosis, blepharospasm, and a moderate amount of mucous discharge. The clinical diagnosis was stromal abscess with reflex uveitis. A differential diagnosis should include conditions affecting the anterior part of the cornea, such as an epithelial inclusion cyst and a corneal ulcer. The inclusion cyst, contrarily to the corneal abscess, doesn't cause pain, meanwhile, the corneal ulcer was ruled out by the Fluorescein Staining Test. The recommended treatment was surgical, through lamellar keratectomy, followed by overlapping pedicled conjunctival graft and third eyelid flap. In association with the surgical treatment, oral antibiotics, anti-inflammatory, and opioids, plus topical antibiotics and autologous serum eye drop. Seventy days post-surgery, the previously observed inflammatory signs were no longer present. In the conjunctival graft insertion site perpetuated a scar leucoma with few blood vessels. The therapy was proven effective in solving the stromal abscess and in visual maintenance. Despite the located opacity due to leucoma, it barely causes any impairment, once its lateral position won't impact the central vision, which is more important to predator species than the peripheral vision.Discussion: Stromal abscess is a pathological condition in which an initial perforating corneal injury leads to a rupture of the epithelial barrier, allowing the access of bacterial, fungus, or foreign bodies of organic nature. The morbidity is more frequent in horses, but this report shows that although uncommon, stromal abscesses can occur in dogs. The diagnosis was achieved by an analysis of the clinical history and findings. Conditions that affect the anterior cornea must be among differential diagnoses. Treatment aims for the removal of infectious material with debridement and curetting of the stroma, by performing the lamellar keratoplasty technique, which produces a corneal wound. The implementation of a pedicled conjunctival graft allows, the influx of growth factors, active replication of stromal collagen by fibroblasts, and direct arrival of antibiotics through the blood supply to the exposed portion of the cornea. The third eyelid flap is questioned by some authors, once it complicates the post-op follow up, and hinder the topical therapy from directly reaching the eye surface. Autologous serum: A blood-derived product often used to control corneal melting. The Federal Medicine Board determined that autologous serum eyedrops therapy has been scientifically proven effective, being used worldwide in the treatment of severe eye surface conditions. In Veterinary, studies also demonstrated that autologous serum can improve improve the corneal re-epithelialization in dogs. Keywords: autologous serum, keratectomy, ophthalmology, veterinary.Título: Abscesso estromal em córnea de cãoDescritores: soro autólogo, ceratectomia, oftalmologia, veterinária.

Changing trends in the corneal transplantation and the impact of the COVID-19 pandemic on corneal transplant recipient selection.

PURPOSE:The aim of this study was to analyze the trends in the major indications and types of keratoplasty over a 15-year period and to determine the effect of the coronavirus disease-2019 (COVID-19) pandemic on the selection of corneal transplant recipients at a tertiary referral center in Turkey.METHODS:We retrospectively reviewed the data of patients who underwent keratoplasty at the center from January 2006 to March 2021. The keratoplasty indications and types of surgery were evaluated after classification into three groups (period I – January 2006–December 2012; period II – January 2013–March 2020; COVID-19 period – April 2020–March 2021).RESULTS:A total of 5016 corneal transplants were performed in 3862 patients. Lamellar keratoplasty (LK) techniques were found to demonstrate a statistically significantly increasing trend compared to penetrating keratoplasty in the period between 2006 and 2021 (χ2 = 240.55, P < 0.001). The top 4 indications over the 15-year period were aphakic/pseudophakic bullous keratopathy (BK) (1105, 22%), keratoconus (1085, 21.6%), regraft (1084, 21.6%), and keratitis (645, 12.8%). The most common keratoplasty indication during the COVID-19 period was regraft (27, 54.0%), followed by BK (13, 26.0%) and corneal perforation (5, 10%).CONCLUSION:BK was the most common keratoplasty indication at our clinic during the 15-year period. LK rates have been found to increase in recent years, although still not reaching the rates of developed countries. There was a marked decrease in the number of keratoplasties during the COVID-19 pandemic and patients requiring urgent keratoplasty or those who suffered from a painful eye were prioritized.

Preferred practice pattern and observed outcome of deep anterior lamellar keratoplasty - A survey of Indian corneal surgeons.

Purpose:This study aimed to assess the preferred surgical technique and outcome of deep anterior lamellar keratoplasty (DALK) among corneal surgeons in India.Methods:An online questionnaire-based cross-sectional survey was conducted among members of the Cornea Society of India (CSI) with experience of performing >10 DALK procedure. The responses pertaining to their surgical experience, preferred technique, complications, and outcome of DALK were collected and analyzed.Results:A total of 156 responses were received. In total, 35.9% of participants reported annual keratoplasty of >50, and DALK constituted >25% surgeries for 25% of participants. Ectatic corneal disorder was reported as the most common indication for DALK by 71.6% of the respondents. Big-bubble (BB) DALK (WA-1.82) was the most preferred technique, along with suction trephine (50%) for partial trephination and bottom port cannula (45.5%) for BB formation. On statistical analysis, no difference was observed in the surgeon reported success rate of BB formation with or without anterior lamellar keratectomy (ALK) (χ2 (1,156) = 3.1498, P = 0.08) or paracentesis (χ2 (1,156) = 0.2737, P = 0.60) before stromal air injection, and method of stromal air injection (χ2 (1,156) = 4.7325, P = 0.09). Conversion to penetrating keratoplasty was reported by 16% of participants in >25% cases, while 66.7% reported in <10% cases. Cataract and double anterior chamber were the most common complications. 50% of participants suggested that >20 procedures are required to overcome the learning curve.Conclusion:BB DALK is the most commonly practiced DALK technique, and its success is independent of ALK and paracentesis being performed prior to air injection and method of air injection (cannula/needle).

Crescent-shaped anterior lamellar keratoplasty as treatment of corneal perforation in peripheral ulcerative keratitis

Purpose: to raise awareness of potential severe ocular complications associated with autoimmune diseases and to describe the surgical technique of crescent-shaped anterior lamellar keratoplasty to treat a corneal perforation in peripheral ulcerative keratitis. Methods and Materials: Case report. Results: A female patient with 59 years old, with history of longstanding rheumatoid arthritis, presented with redness and photophobia in the right eye. As past ocular history, the patient had a severe keratoconjunctivitis sicca and a corneal ulcer in the right eye. Clinical examination revealed an epithelial defect with a significant inferior corneal thickness decrease. Topical steroids, antibiotics and a therapeutic contact lens were prescribed. One month later, a corneal perforation was observed and a crescent-shaped deep anterior lamellar keratoplasty was then performed. Conclusion: The clinical course of peripheral ulcerative keratitis depends on the associated systemic pathology, being essential a multidisciplinary approach by ophthalmologists and rheumatologists to allow systemic control of the autoimmune disease, avoiding possible complications such as eye perforation.

Ceratoplastia lamelar anterior profunda (DALK) como tratamento de úlcera estromal profunda em cão: relato de caso

Characterized by the rupture of the corneal epithelium, corneal ulcers threaten ocular integrity, with multifactorial development, such as decreased protection and excessive abrasion applied to the corneal surface. Keratoplasty restores the corneal anatomy, removing the inflamed or infected tissues, in order to promote visual acuity. The technique of deep anterior lamellar keratoplasty (DALK) selectively removes the diseased layers of the cornea, keeping the Descemet membrane and endothelium healthy, reducing the risk of rejection, aimed at tissue recovery. In the present report, a canine, from the Shih Tzu breed, a female, that has not been castrated, 2 years and 6 months old, was treated, she had a history of ocular discomfort and mucous secretion in both eyes. In the ophthalmic examination, keratoconjunctivitis sicca was found in the left eye and ectopic cilia was found in both eyes. With the aid of a fluorescein test, the presence of a deep stromal ulcer affecting the right eye was confirmed. The patient underwent ectopic cilia removal using the wedge resection technique and an allogeneic corneal transplantation using DALK, with only the diseased epithelium and stroma being replaced, reducing the risk of rejection and failures related to surgery. 90 days after the procedure, there was no reaction to the graft, there was complete epithelial repair and maintenance of visual function with slight corneal opacity. &nbsp

Preliminary Results of a Novel Standardized Technique of Femtosecond Laser-Assisted Deep Anterior Lamellar Keratoplasty for Keratoconus.

Purpose To evaluate the feasibility and the initial outcomes of a novel standardized surgical technique of femtosecond laser- (FSL-) assisted big-bubble deep anterior lamellar keratoplasty (BBDALK) for eyes with keratoconus. Methods This prospective interventional case series included 11 consecutive FSL-assisted BBDALK procedures performed for the eyes with keratoconus from September 2019 to December 2019. The FSL was used to create (i) an intrastromal channel incision (1.7 mm in length, 4.6 mm in width, 80% depth, and cut energy of 1.70 μJ) and (ii) a 9.0 mm diameter circular lamellar side cut 65 μm above the endothelium (cut energy of 0.90 μJ) intersecting the intrastromal incision. In the operating room, a blunt dissector was used to open the intrastromal channel incision, through which a blunt spatula was inserted, tangentially advanced towards the center of the cornea, and replaced with a blunt cannula for pneumatic dissection. The subsequent surgical steps did not differ from the conventional technique. Main outcome measures were the success rate of pneumatic dissection and the percentage of intraoperative complications. Results Eleven eyes of 11 patients (6 males and 5 females; mean age: 34.54 ± 13.23 years) underwent FSL-assisted DALK. Using the FSL, both corneal incisions (lamellar side cut and intrastromal channel incision) were successfully created in all cases without the need for repeat docking or additional dissection. Pneumatic dissection with type 1 bubble formation succeeded in all 11 eyes (100%). DALK surgery was completed uneventfully in all cases. Descemet membrane perforation did not occur in any case, and no procedure was converted to penetrating keratoplasty. Conclusion Using standardized FSL parameters for both incision design and cut energy in BBDALK surgery, pneumatic dissection can be achieved in a very high rate of cases with minimal risk of intraoperative complications.

Recurrent pterygium – features of surgical treatment

Pterygium is a fibrovascular degenerative condition of the subconjunctival tissue that proliferates and grows into the cornea in the form of a vascularized fold, destroying the surface layers of the stroma and Bowmans membrane. This disease is common throughout the world. The etiology is not clear, but it is known that the appearance of pterygium is associated with exposure of the eye to ultraviolet rays. The treatment of the de novo occurring pterygium is a relatively simple task and involves surgical removal. But a simple excision is currently unacceptable due to the high recurrence rate. In order to minimize the risk of relapse, numerous adjuvant treatment methods are used, which include anti-metabolites such as Mitomycin C and 5-fluorouracil, amniotic membrane, various types of conjunctival and or limbal grafts; medications such as anti-vascular endothelial growth factor are sometimes used. In the clinical case presented in the article, we successfully used the technique of anterior lamellar keratoplasty and autoconjunctival transplantation in combination with intra-operative use of anti-metabolite Mitomycin C in a young patient with recurrent stage IV pterygium (degree of activity 3) twice unsuccessfully operated on. As a result of this surgical technique, the transparency of the cornea was restored and high visual acuity was obtained.

Queratoplastia lamelar vs Queratoplastia penetrante

Introducción: El queratocono es un proceso progresivo, bilateral, asimétrico, no inflamatorio del espesor estromal, en el que la forma normal de la córnea se distorsiona y desarrolla una deformación similar a un cono, que modifica y altera progresivamente la visión y la hace cada vez más borrosa, con la aparición de una disminución de la agudeza visual por aumento de la miopía, astigmatismo regular o irregular, y el desarrollo de opacidades corneales.&#x0D; Objetivos: Realizar una revisión sistemática de la literatura en el periodo 2014-2018 sobre la eficacia de la queratoplastia lamelar frente a la queratoplastia penetrante en el tratamiento quirúrgico del queratocono. Material y Métodos: Se realizó una revisión sistemática de la literatura que incluyó metaanálisis con nivel de evidencia tipo A, se emplearon buscadores científicos como Elsevier, Scopus, Pubmed, Cochrane Library, Scielo en el período 2014 – 2018, sobre la eficacia de la queratoplastia lamelar frente a la técnica penetrante en el tratamiento quirúrgico del queratocono. Se incluyeron 23 artículos tipo Metaanálisis, revisiones sistemáticas y ensayos clínicos sobre el tema.&#x0D; Resultados: Se revisaron 24 artículos científicos publicados en las revistas Elsevier, Scopus, Pubmed, Cochrane Library, Scielo en el período 2014 – 2018. De la revisión efectuada se pudo determinar la efectividad de la Queratoplastia Lamelar y sus potencialidades en la Oftalmología.&#x0D; Conclusión: De acuerdo a la evidencia revisada, se concluye que la técnica de queratoplastia lamelar resulta ser más eficaz y con menos taza rechazo endotelial frente a la queratoplastia penetrante dentro del tratamiento quirúrgico de queratocono