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Possibilities of using stem cells for treatment of ocular surface injuries
Kössl, Jan ; Holáň, Vladimír (advisor) ; Drbal, Karel (referee)
Ocular surface defects are one of the most common causes of impaired vision or even blindness. Corneal transplantation is the first choice of the treatment of these defects. If the damage is extensive and includes the limbus, niche of limbal stem cells (LSCs), LSC deficiency (LSCD) occurs and reparation with regeneration of cornea is impaired. The only way to treat LSCD is limbal transplantation or transplantation of autologous LSCs from the healthy eye. In cases of bilateral LSCD there are no autologous LSCs available. The use of allogeneic LSCs is associated with the requirement of systemic or local administration of immunosuppressive drugs which have often negative side-effects and outcomes remain uncertain. The alternative for treatment of ocular surface defects and LSCD is finding a new source of an appropriate autologous stem cell substitute which are e.g. mesenchymal stem cells (MSCs). These cells can be obtained from bone marrow or adipose tissue of the particular patient. MSCs can be easily cultivated ex vivo and can be transferred onto the damaged ocular surface using appropriate scaffold. Here they can differentiate to corneal epithelial cells, have immunomodulatory properties and produce numerous trophic and growth factors. The experiments with MSCs on animal models of mechanically or...
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Implementation of novel methods of tissue preparation and storage for transplantation purposes in ophthalmology
Rybičková, Ivana ; Jirsová, Kateřina (advisor) ; Vlková, Eva (referee) ; Čejková, Jitka (referee)
Introduction: Recent advances in posterior lamellar keratoplasty necessitated the preparation of posterior corneal lamellae even in the Czech Republic. The aim of this work was to introduce and standardize a novel method of manual preparation of corneal lamellae for Descemet Membrane Endothelial Keratoplasty with a Stromal rim (DMEK-S) in an ocular tissue bank. After setting the criteria for endothelial quality, we obtained a licence to provide the tissues for transplantation purposes. The obtained results were analysed after two years. Furthermore, a novel lamellar insertion technique using a cartridge was assessed. The potentials for the long-term storage of posterior corneal lamellae by the vitrification in liquid ethane was studied using human amniotic membrane as a model tissue. Material and Methods: Corneoscleral buttons stored in tissue cultures were used to prepare lamellae consisting of a central zone of endothelium and Descemet membrane supported by a stromal rim at the periphery. The manual preparation was performed on an artificial anterior chamber using the big bubble technique. Endothelial quality was assessed before storage, before and immediately after preparation as well as after 2 days of storage at 31řC. A group of 12 corneas with a live endothelial cell density ≥ 2500 cells/mm2...
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Phenotypical characterization of the healthy human cornea and the alterations caused by posterior polymorphous corneal dystrophy
Reinštein Merjavá, Stanislava ; Jirsová, Kateřina (advisor) ; Martínek, Jindřich (referee) ; Čejková, Jitka (referee)
Purpose: The aim of this work was to characterize the healthy human cornea and the cornea of patients suffering from posterior polymorphous corneal dystrophy (PPCD) using different antibodies. Despite the fact that PPCD is a very rare disorder, one of the largest groups of PPCD patients in the world comes from the Czech Republic. This offers us the opportunity to investigate the changes on the clinical, cellular and molecular levels. Material and Methods: A collection of 25 control corneas as well as 16 pathological corneas from PPCD patients were used. Epithelial (cytokeratins) and mesothelial markers (mesothelin, calbindin 2, HBME-1 protein) were detected in all layers of the healthy corneas using immunocyto- and immunohistochemistry. The expression of all markers was confirmed using molecular methods as well (RT-PCR and Western blot). Changes in the expression of cytokeratins and changes in the extracellular matrix structure (collagen IV and VIII) were studied in the PPCD corneas. Combined fluorescent immunohistochemistry with fluorescence in situ hybridization were used in order to characterize the origin of abnormal cells on the posterior graft surface, which cause the recurrence of the PPCD after penetrating keratoplasty surgery. Results: Changes in the cytokeratin expression (strong...
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Processing and analysis of ophthalmologic images and data
Brož, Petr ; Hozman, Jiří (referee) ; Kolář, Radim (advisor)
In this work is describe anatomy and physiology of the cornea. The following are the primary non-inflamatory degeneration of the cornea. Then describe the physical principles diagnostic devices for cornea – keratometer, pachymeter, Michelson interferometr and optical coherence tomography (OCT). At the end of the theoretical introduction is describes the principle of laser correction surgery – LASIK. The practical part is divided into two main objectives. The first task is propose an algorithm for automatic detection of corneal surface and then calculation of corneal thickness and size of the chamber angle in Matlab. The aim of the second task is image flap analysis for boundary detection.
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