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Gerrit R J Melles - One of the best experts on this subject based on the ideXlab platform.
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Updates in anterior Lamellar Keratoplasty: the state of the debates
Expert Review of Ophthalmology, 2016Co-Authors: Jack S. Parker, Korine Van Dijk, Gerrit R J MellesAbstract:ABSTRACTIntroduction: Deep and Superficial anterior Lamellar Keratoplasty (DALK and SALK, respectively) are rapidly replacing penetrating Keratoplasty (PK) as the treatments of choice for anterior corneal disorders worldwide. Nevertheless, significant disagreements remain which encompass nearly every aspect of both operations and whether there are better alternatives.Areas covered: Here, we perform a comprehensive literature review of all articles published in the English language, indexed on Pubmed, and within the past 5 years on the subject of ‘anterior Lamellar Keratoplasty.’ From these articles, the most salient disputes are enumerated and presented.Expert commentary: Presently, there is no consensus in the areas of graft preparation, instrumentation, or operative technique for DALK/SALK. As new evidence emerges, these debates may be clarified, or – instead – merely forgotten, as alternative surgical techniques arise to supplant ALK entirely.
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Lamellar Keratoplasty. Back to the future
Der Ophthalmologe, 2005Co-Authors: Gerd Geerling, Gernot I.w. Duncker, J. Krumeich, Gerrit R J MellesAbstract:In 1840 Muhlbauer was the first to describe a technique for anterior Lamellar Keratoplasty (LKP). However, in the second half of the twentieth century penetrating Keratoplasty (PKP) became the gold standard. Although it is associated with a higher risk for serious complications -- it is technically easier to perform and avoids wound healing reactions in the Lamellar interface and thus resulting in better visual acuity. In view of the pathology, replacing all layers of the cornea including healthy parts can be considered therapeutic "overkill" for many corneal graft indications. Several innovative surgical techniques have recently been described which allow the Lamellar dissection of recipient and donor cornea with good reproducibility in almost every desired depth. This now allows the recipient endothelium and Descemet's membrane to be selectively replaced or preserved and to avoid formation of an optical barrier in the Lamellar interface in eyes undergoing Lamellar Keratoplasty for optical indications. The most important principal advantage of an anterior LKP -- to minimize the risk of an immune reaction in the graft -- is even more important in tectonic indications. From the large number of variations, the surgical technique, results, and problems with anterior and posterior LKP for optical indications as well as Lamellar segment Keratoplasty and epiKeratoplasty for tectonic indications are discussed.
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endothelial cell density after posterior Lamellar Keratoplasty melles techniques 3 years follow up
American Journal of Ophthalmology, 2004Co-Authors: Bart T H Van Dooren, W. Houdijn Beekhuis, Paul G H Mulder, Carla P Nieuwendaal, Gerrit R J MellesAbstract:Abstract Purpose To report the midterm endothelial cell density measurements after posterior Lamellar Keratoplasty (Melles techniques). Design Cohort study. Methods Fifteen consecutive eyes of 15 patients in whom a posterior Lamellar Keratoplasty procedure was performed for pseudophakic bullous keratopathy or Fuchs' endothelial dystrophy were evaluated. In 11 corneas the donor tissue was inserted through a 9.0-mm sclerocorneal pocket incision (technique A); in four cases the donor was folded and inserted through a 5.0-mm incision (technique B). Specular microscopy was performed at 6, 12, 24, and 36 months after surgery, to measure the endothelial cell density. Results Mean postoperative endothelial cell density averaged 2,126 cells/mm 2 (±548) at 6 months, 1,859 cells/mm 2 (±477) at 12 months, 1,385 cells/mm 2 (±451) at 24 months, and 1,047 cells/mm 2 (±425) at 36 months. Conclusion In posterior Lamellar Keratoplasty, the donor corneal endothelium showed a decrease in cell density similar to that after conventional full-thickness penetrating Keratoplasty.
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endothelial cell density after deep anterior Lamellar Keratoplasty melles technique
American Journal of Ophthalmology, 2004Co-Authors: Bart T H Van Dooren, Gerrit R J Melles, Paul G H Mulder, Carla P Nieuwendaal, Houdijn W BeekhuisAbstract:Abstract Purpose To measure the recipient endothelial cell loss after the Melles technique for deep anterior Lamellar Keratoplasty. Methods In 21 eyes of 21 patients, a deep anterior Lamellar Keratoplasty procedure was performed. Before surgery and at 6, 12, and 24 months after surgery, specular microscopy was performed to evaluate the endothelial cell density. For each postoperative time interval, the mean endothelial cell loss relative to the preoperative value was calculated. Results Mean postoperative endothelial cell loss averaged 283 cells/mm 2 (± 293) at 6 months, 335 cells/mm 2 (± 309) at 12 months, and 421 cells/mm 2 (± 316) at 24 months. Estimate relative endothelial cell density losses obtained by mixed model analysis of variance were 11.1%, 2.0%, and 1.2%, respectively, each time compared with its previous measurement point. Second order comparisons showed that the loss within the first 6 months was significantly higher than after 6 months. Conclusion In deep anterior Lamellar Keratoplasty, the recipient corneal endothelium showed a small initial drop in endothelial cell density followed by a physiologic rate of cell loss. Cell survival after Lamellar Keratoplasty may be expected to be better when compared with that following penetrating Keratoplasty.
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New techniques in Lamellar Keratoplasty.
Current Opinion in Ophthalmology, 2002Co-Authors: Jorge L. Alió, Sunil Shah, Carmen Barraquer, Kamil Bilgihan, Mohammed Anwar, Gerrit R J MellesAbstract:In the past years, several Lamellar Keratoplasty surgical techniques have been developed, modified or improved in the past years, including microkeratome assisted anterior and posterior Lamellar Keratoplasty, anterior Lamellar Keratoplasty using air-dissection or visco-dissection, sutureless posterior Lamellar Keratoplasty, LASIK for postKeratoplasty astigmatism, and excimer laser assisted keratophakia for keratoconus or to manage complications after LASIK. These procedures may continue to gain interest as alternative procedures for a penetrating Keratoplasty in the treatment of various corneal disorders.
Stephen J Tuft - One of the best experts on this subject based on the ideXlab platform.
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fixed dilated pupil urrets zavalia syndrome after air gas injection after deep Lamellar Keratoplasty for keratoconus
American Journal of Ophthalmology, 2002Co-Authors: Vincenzo Maurino, Bruce D Allan, Julian D Stevens, Stephen J TuftAbstract:Abstract PURPOSE: To describe three cases of fixed dilated pupil and presumed iris ischemia (Urrets-Zavalia syndrome) after anterior chamber air/gas injection after deep Lamellar Keratoplasty for keratoconus. METHODS: Interventional case series. Three eyes of three patients with keratoconus underwent deep Lamellar Keratoplasty and intraoperative or postoperative injection of air/gas in the anterior chamber to appose the host-donor Lamellar graft interface. RESULTS: Urrets-Zavalia syndrome was diagnosed on clinical grounds in three cases and was associated with the Descemet membrane microperforation intraoperatively and introduction of air/gas into the anterior chamber intraoperatively or postoperatively. CONCLUSION: A fixed dilated pupil is an uncommon complication of penetrating Keratoplasty for keratoconus that can also develop after deep Lamellar Keratoplasty. Leaving an air or gas bubble in the anterior chamber of a phakic eye after deep Lamellar Keratoplasty is a risk factor and should therefore be avoided.
Abhiyan Kumar - One of the best experts on this subject based on the ideXlab platform.
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deep Lamellar Keratoplasty versus penetrating Keratoplasty for corneal lesions
Cornea, 1999Co-Authors: Anita Panda, Lalit Mohan Singh Bageshwar, J Singh, Abhiyan KumarAbstract:PurposeTo compare the effectiveness of deep Lamellar Keratoplasty (DLK) with that of penetrating Keratoplasty (PKP) in cases of corneal lesions not involving the endothelium.MethodsForty-eight eyes with leukomatous corneal opacity (n = 33), keratoconus with apical scarring (n = 6), granular corneal
Vincenzo Maurino - One of the best experts on this subject based on the ideXlab platform.
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fixed dilated pupil urrets zavalia syndrome after air gas injection after deep Lamellar Keratoplasty for keratoconus
American Journal of Ophthalmology, 2002Co-Authors: Vincenzo Maurino, Bruce D Allan, Julian D Stevens, Stephen J TuftAbstract:Abstract PURPOSE: To describe three cases of fixed dilated pupil and presumed iris ischemia (Urrets-Zavalia syndrome) after anterior chamber air/gas injection after deep Lamellar Keratoplasty for keratoconus. METHODS: Interventional case series. Three eyes of three patients with keratoconus underwent deep Lamellar Keratoplasty and intraoperative or postoperative injection of air/gas in the anterior chamber to appose the host-donor Lamellar graft interface. RESULTS: Urrets-Zavalia syndrome was diagnosed on clinical grounds in three cases and was associated with the Descemet membrane microperforation intraoperatively and introduction of air/gas into the anterior chamber intraoperatively or postoperatively. CONCLUSION: A fixed dilated pupil is an uncommon complication of penetrating Keratoplasty for keratoconus that can also develop after deep Lamellar Keratoplasty. Leaving an air or gas bubble in the anterior chamber of a phakic eye after deep Lamellar Keratoplasty is a risk factor and should therefore be avoided.
W. Houdijn Beekhuis - One of the best experts on this subject based on the ideXlab platform.
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endothelial cell density after posterior Lamellar Keratoplasty melles techniques 3 years follow up
American Journal of Ophthalmology, 2004Co-Authors: Bart T H Van Dooren, W. Houdijn Beekhuis, Paul G H Mulder, Carla P Nieuwendaal, Gerrit R J MellesAbstract:Abstract Purpose To report the midterm endothelial cell density measurements after posterior Lamellar Keratoplasty (Melles techniques). Design Cohort study. Methods Fifteen consecutive eyes of 15 patients in whom a posterior Lamellar Keratoplasty procedure was performed for pseudophakic bullous keratopathy or Fuchs' endothelial dystrophy were evaluated. In 11 corneas the donor tissue was inserted through a 9.0-mm sclerocorneal pocket incision (technique A); in four cases the donor was folded and inserted through a 5.0-mm incision (technique B). Specular microscopy was performed at 6, 12, 24, and 36 months after surgery, to measure the endothelial cell density. Results Mean postoperative endothelial cell density averaged 2,126 cells/mm 2 (±548) at 6 months, 1,859 cells/mm 2 (±477) at 12 months, 1,385 cells/mm 2 (±451) at 24 months, and 1,047 cells/mm 2 (±425) at 36 months. Conclusion In posterior Lamellar Keratoplasty, the donor corneal endothelium showed a decrease in cell density similar to that after conventional full-thickness penetrating Keratoplasty.
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The future of Lamellar Keratoplasty.
Current Opinion in Ophthalmology, 1999Co-Authors: Gerrit R J Melles, Annette J.m. Geerards, Lies Remeijer, W. Houdijn BeekhuisAbstract:New surgical techniques in Lamellar Keratoplasty, including phototherapeutic keratectomy, automated Lamellar keratectomy, plano-epiKeratoplasty, deep anterior Lamellar Keratoplasty, combined amniotic membrane and limbal transplantation, large-diameter corneoscleral Lamellar Keratoplasty, and posteri
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a new surgical technique for deep stromal anterior Lamellar Keratoplasty
British Journal of Ophthalmology, 1999Co-Authors: Gerrit R J Melles, Lies Remeijer, W. Houdijn Beekhuis, F Lander, F J R Rietveld, Perry S BinderAbstract:AIMS—To describe a new surgical technique for deep stromal anterior Lamellar Keratoplasty. METHODS—In eye bank eyes and sighted human eyes, aqueous was exchanged by air, to visualise the posterior corneal surface−that is, the "air to endothelium" interface. Through a 5.0 mm scleral incision, a deep stromal pocket was created across the cornea, using the air to endothelium interface as a reference plane for dissection depth. The pocket was filled with viscoelastic, and an anterior corneal lamella was excised. A full thickness donor button was sutured into the recipient bed after stripping its Descemet's membrane. RESULTS—In 25 consecutive human eye bank eyes, a 12% microperforation rate was found. Corneal dissection depth averaged 95.4% (SD 2.7%). Six patient eyes had uneventful surgeries; in a seventh eye, perforation of the Lamellar bed occurred. All transplants cleared. Central pachymetry ranged from 0.62 to 0.73 mm. CONCLUSION—With this technique a deep stromal anterior Lamellar Keratoplasty can be performed with the donor to recipient interface just anterior to the posterior corneal surface. The technique has the advantage that the dissection can be completed in the event of inadvertent microperforation, or that the procedure can be aborted to perform a planned penetrating Keratoplasty. Keywords: corneal surgery; Lamellar Keratoplasty; air; optical interface
