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Publications (8)7.08 Total impact

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    ABSTRACT: A 39-year-old male patient underwent uncomplicated deep anterior lamellar keratoplasty due to keratoconus. On day 5 after surgery, small whitish infiltrates developed in the corneal interface. The diagnosis of fungal keratitis was made when the culture medium of the graft grew Candida after the surgical intervention. Despite intensive antimycotic treatment and irrigation of the interface, the infiltrates persisted and eventually enlarged. Therefore, revision surgery with penetrating keratoplasty was performed. Microbiological analysis showed Candida orthopsilosis in the culture of the excised graft button. Histopathological staining of the excised graft showed periodic acid-Schiff-positive and Grocott methenamine silver-positive clusters of yeast between Descemet's membrane and the deep corneal stroma with focal perforations through Descemet's membrane. The treatment of mycotic keratitis caused by C orthopsilosis is challenging. Antimycotic treatment was unsuccessful in this case. Progression of the keratitis and perforation of Descemet's membrane suggest that early surgical intervention by penetrating keratoplasty is required.
    Case Reports 01/2013; 2013.
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    ABSTRACT: In recent years many three-dimensional cornea models have been developed. However, they show poor collagen stability in the stroma. Transglutaminases (Tgases) are calcium-dependent proteins which play an important role in cross-linking of the corneal stroma. The purpose of this study was to find out whether it is possible to induce in vitro cross-linking of the stroma in an artificial hemicornea model with the help of Tgases. For the construction of the hemicornea, human SV40 adenovector corneal epithelial cells (HCE) and human SV40 adenovector corneal keratocytes (HCK) were cultivated. Confluent HCK cells were treated for 24 h with transforming growth factor beta (TGFb) 1, 2 and 3 at different concentrations as well as with other growth factors and the treated cells were compared to untreated cultivated cells. The quantification of the expression of the Tgases by HCKs was examined with the use of real time PCR, Western blot imaging and immunochemistry. All concentrations of TGFbs used resulted in a significant increase of Tgase-mRNA, Tgase protein level and Tgase activity. The Tgases remained unaffected after treatment with other growth factors in comparison to untreated control cells. Treatment of the hemicornea with TGFb2 showed a very strong contraction and haze in comparison to the untreated hemicornea. It has been shown for the first time that TGFb induces a strong expression of Tgases in HCK cells. This effect caused an undesired contraction and haze of the human hemicornea model. Further research is necessary in order to find out whether the induction of Tgases in the HCK cells can be regulated without losing stability of the constructed hemicornea.
    Der Ophthalmologe 04/2012; 109(6):583-90. · 0.53 Impact Factor
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    ABSTRACT: To describe a patient with interlamellar stromal keratitis induced by increased intraocular pressure (IOP) [Pressure-induced interlamellar stromal keratitis (PISK)] after laser in situ keratomileusis (LASIK) surgery. Case report and review of the literature. We report a case of interlamellar stromal keratitis induced by increased IOP after LASIK surgery. A 42-year-old man presented with persistent interface haze after uneventful LASIK. The patient described onset of decreased visual acuity after the first 2 postoperative weeks, failed to improve with high-dose topical steroid drops, and had significantly elevated IOP values up to 48 mm Hg. IOP was resistant to maximal topical antiglaucomatous therapy. The patient showed both improvement in visual acuity and decrease in interface haze after discontinuation of topical steroids and lowering of IOP by both topical and systemic treatment. Slit-lamp optical coherence tomography ruled out a fluid accumulation in the interface. PISK appears clinically almost identical to diffuse lamellar keratitis after LASIK. It is important to measure the IOP and be suspicious when a diffuse interface haze occurs after the first postoperative week, is resistant to or even exacerbates in response to an increase in topical steroid treatment, and is not associated with other causative events. Slit-lamp optical coherence tomography is a valuable tool that allows differentiation between space-occupying interface fluid collection and non-space-occupying interface fluid collection to avoid falsely low or normal IOP measurements in PISK.
    Cornea 08/2011; 30(8):920-3. · 1.75 Impact Factor
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    ABSTRACT: PURPOSE:: To describe a patient with interlamellar stromal keratitis induced by increased intraocular pressure (IOP) [Pressure-induced interlamellar stromal keratitis (PISK)] after laser in situ keratomileusis (LASIK) surgery. METHODS:: Case report and review of the literature. RESULTS:: We report a case of interlamellar stromal keratitis induced by increased IOP after LASIK surgery. A 42-year-old man presented with persistent interface haze after uneventful LASIK. The patient described onset of decreased visual acuity after the first 2 postoperative weeks, failed to improve with high-dose topical steroid drops, and had significantly elevated IOP values up to 48 mm Hg. IOP was resistant to maximal topical antiglaucomatous therapy. The patient showed both improvement in visual acuity and decrease in interface haze after discontinuation of topical steroids and lowering of IOP by both topical and systemic treatment. Slit-lamp optical coherence tomography ruled out a fluid accumulation in the interface. CONCLUSIONS:: PISK appears clinically almost identical to diffuse lamellar keratitis after LASIK. It is important to measure the IOP and be suspicious when a diffuse interface haze occurs after the first postoperative week, is resistant to or even exacerbates in response to an increase in topical steroid treatment, and is not associated with other causative events. Slit-lamp optical coherence tomography is a valuable tool that allows differentiation between space-occupying interface fluid collection and non-space-occupying interface fluid collection to avoid falsely low or normal IOP measurements in PISK.
    Cornea 04/2011; · 1.75 Impact Factor
  • R Meiller, FK Horn, FE Kruse
    Klinische Monatsblatter Fur Augenheilkunde - KLIN MONATSBL AUGENHEILK. 01/2008; 225.
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    ABSTRACT: To evaluate the efficacy of the laser photolysis system (LPS) (A.R.C. Laser GmbH) in removing lens epithelial cells (LECs) to prevent posterior capsule opacification (PCO) in an in situ model. Department of Ophthalmology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany. Twelve enucleated porcine eyes fixed in a specially developed eye holder were randomly assigned to the control or treatment group. The cornea and iris were removed from all eyes, and a small paracentral capsulorhexis was performed. The lens nucleus and cortex were extracted by hydroexpression. The tip of the LPS was inserted into the capsular bag of eyes in the treatment group, and 50 pulses (10 mJ) were applied to the anterior capsule. All capsules were evaluated for remaining LECs by confocal laser scanning microscopy (HRT II with the Rostock Cornea Module, Heidelberg Engineering) and standard histology (hematoxylin-eosin and periodic acid-Schiff stains). In the control group, a homogenous layer of LECs attached to the anterior capsule was seen with both evaluation methods. In the treatment group, no LECs adherent to the anterior capsule were detected, suggesting complete ablation of LECs from the capsule. Small islands of equatorial LECs were found in places in which the remaining cortical fibers protected cells from the laser shockwave. The results of the confocal laser scanning microscopy were confirmed by standard histology. The LPS completely ablated LECs in an in situ model of cataract extraction. This system might prevent formation of PCO in vivo.
    Journal of Cataract and Refractive Surgery 04/2007; 33(4):697-701. · 2.53 Impact Factor
  • Klinische Monatsblatter Fur Augenheilkunde - KLIN MONATSBL AUGENHEILK. 01/2007; 224.
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    ABSTRACT: Ziel In den letzten Jahren wurden viele 3-dimensionale humane Hornhautmodelle entwickelt, die eine fehlende Vernetzung und mangelnde Festigkeit im Stroma aufweisen. Transglutaminasen (Tgasen) sind Kalzium-abhängige Proteine, die bei der Vernetzung des Hornhautstromas eine entscheidende Rolle spielen. Ziel dieser Arbeit ist herauszufinden, inwieweit eine Vernetzung des Stromas einer künstlichen Hornhaut in vitro durch Tissue-Transglutaminasen (Tgasen) induzierbar ist. Material und Methoden Für die Konstruktion der Hemikornea wurden humane SV40-Adenovektor-transformierte Korneaepithelzellen (HCE) und humane SV40-Adenovektor-transformierte Korneakeratozyten (HCK) kultiviert. Konfluente HCK-Zellen wurden für 24 h, mit unterschiedlichen Konzentrationen von TGF-b1, 2 und 3 („transforming growth factor beta“) sowie anderen Wachstumsfaktoren behandelt. Die behandelten Zellen wurden mit unbehandelten Zellkulturen verglichen. Die Quantifizierung der Expression der Tgase durch die humanen Keratozyten wurde auf der mRNA-Ebene („Real-time-PCR“) als auch auf der Proteinebene (Western-Blot, Immunhistochemie, extrazelluläre Transglutaminasenaktivität) untersucht. Ergebnisse Alle verwendeten Konzentrationen und Isoformen von TGF-b zeigten einen signifikanten Anstieg der Tgase-mRNA, Tgase-Proteine und Tgase-Aktivität. Diese blieb unverändert nach Behandlung mit anderen Wachstumsfaktoren verglichen mit unbehandelten Kontrollzellen. Nach Behandlung der Hemikorneakonstrukte mit entsprechenden TGF-b2-Konzentrationen zeigte sich eine starke Kontraktion und Eintrübung im Vergleich zum Ausgangspunkt. Schlussfolgerung Es wurde zum ersten Mal gezeigt, dass TGF-b eine starke Expression von Transglutaminase in HCK-Zellen induziert. Dieser Effekt führte zu einer unerwünschten Kontraktion und Eintrübung in unserem humanen Hemikorneamodell. Weitere Versuche sind notwendig, um festzustellen, ob es möglich ist, die Induktion der Tgasen in den HCK-Zellen der Konstrukte erfolgreich zu regulieren.
    Der Ophthalmologe 109(6). · 0.53 Impact Factor