P Steven

Publications (11)11.55 Total impact

• Article: [Treatment-refractory anti-laminin 332 mucous membrane pemphigoid. Remission following adjuvant immunoadsorption and rituximab].

  A Recke, I Shimanovich, P Steven, L Westermann, D Zillikens, E Schmidt
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  ABSTRACT: Mucous membrane pemphigoid (MMP) is clinically characterized by predominant involvement of mucous membranes which in case of conjunctival lesions can lead to blindness. In MMP, autoantibodies are directed against different proteins of the dermal-epidermal junction; in 25% of cases, laminin 332 is the target. Anti-laminin 332 MMP with ocular involvement is particularly difficult to treat. A 46-year-old Caucasian man with anti-laminin 332 pemphigoid and extensive oral and nasal erosions as well as severe conjunctival involvement did not respond to intravenous dexamethasone-cyclophosphamide pulses combined with oral cyclophosphamide. After initiation of a therapeutic regimen originally established for the treatment of pemphigus, including immunoapheresis and rituximab in combination with intravenous dexamethasone-cyclophosphamide pulses and oral mycophenolate mofetil, lesions cleared within 4 months and circulating autoantibody levels became undetectable 3 months later. This is the first report of the successful use of adjuvant immunoapheresis and rituximab in previously treatment-refractory anti-laminin 332 MMP.
  Der Hautarzt 06/2011; 62(11):852-8. · 0.58 Impact Factor
• Article: The effect of long-term storage on the biological and histological properties of cryopreserved amniotic membrane.

  H Thomasen, M Pauklin, B Noelle, G Geerling, J Vetter, P Steven, K-P Steuhl, D Meller
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  ABSTRACT: Cryopreserved amniotic membrane (AM) is widely used in ophthalmology because of its anti-angiogenic, anti-inflammatory, and wound healing promoting capabilities. A common method to conserve the tissue is the storage in cryo-medium containing 50% glycerol at -80°C. The aim of this study was to examine the influence of storage time on the sterility as well as the histological and biological properties of cryopreserved AM. Amniotic membrane from different donors was stored in cell culture media containing 50% glycerol for different time periods, on average 4 months (group 1), 15 months (group 2), and 24 months (group 3), at -80°C. Samples of the tissue and cryo-medium were examined for bacterial and fungal contamination. Tissue samples were incubated in 0.5 ml/cm(2) serum-free medium at 37°C. The medium was changed after 1, 2, and 3 days. The proteins released by AM were TCA-precipitated and the presence of the proteins TIMP-1 and IL-1ra was analyzed using Western blotting and semi quantified by means of image analysis. Integrity of the amniotic epithelium and the basement membrane components collagen IV, collagen VII, laminin, laminin 5, and fibronectin were examined by haematoxylin eosin stain and immunohistochemistry in cryosections of AM. None of the examined samples showed bacterial or fungal contamination. The soluble proteins TIMP-1 and IL-1ra were found in all samples of medium incubated for all time periods. The examined proteins were detectable after one-day incubation but the staining signal diminished significantly in the second and third wash after 48 hr and 72 hr. Differences in the intensity of the Western blot signal between the three particular groups were statistically not significant. The epithelia of all samples were intact. The basement membranes of all samples showed a similar distribution of collagen IV, collagen VII, laminin, laminin 5, and fibronectin. Long-term storage of amniotic membrane in cell culture media with 50% glycerol does not significantly impair sterility, histology, or biological properties of AM.
  Current eye research 03/2011; 36(3):247-55. · 1.51 Impact Factor
• Article: Slit-lamp-adapted fourier-domain OCT for anterior and posterior segments: preliminary results and comparison to time-domain OCT.

  M Mueller, C Schulz-Wackerbarth, P Steven, E Lankenau, T Bonin, H Mueller, A Brueggemann, R Birngruber, S Grisanti, G Huettmann
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  ABSTRACT: To evaluate the diagnostic potential of a slit-lamp (SL)-adapted Fourier-domain (= spectral radar, SR) optical coherence tomography (OCT)-SL-SR-OCT-instrument as an in vivo imaging device for use in examinations of the anterior and posterior segments. In a pilot study, 88 eyes from 70 healthy volunteers and patients were examined using a prototype Fourier-domain SL-SR-OCT system. Results were compared to those from the following commercially available systems: the 1310-nm SL-OCT (Heidelberg Engineering, Heidelberg, Germany) for anterior segment and the Stratus OCT (Zeiss Meditec, Jena, Germany) for posterior segment imaging. Our SL-SR-OCT provides 1025 axial scans, 5000 Hz line-scan frequency, scan length of up to 8 mm, axial depth in air of 3.5 mm, and resolution of 9 mum. For posterior visualization, a hand-held 78-diopter ophthalmoscopic lens was used. Our SL-SR-OCT system allowed simultaneous scanning with direct biomicroscopic and SL imaging of anterior and posterior segment structures. Anatomical structures and pathological changes were displayed with high resolution and excellent contrast. Measurements of corneal and retinal thickness were possible. In comparison to images obtained by the SL-OCT, our SL-SR-OCT boasted a higher resolution, thus providing more clinically relevant details of the corneal epithelium, internal structure of filtering blebs, etc. Complete imaging of the chamber angle was limited, however, due to the backscattering properties of the sclera at 830 nm. For posterior segment imaging, excellent delineation of the macula and optic nerve head details, with a distinct portrayal of macular pathology and retinal edema, was possible with SL-SR-OCT. SL-SR-OCT enables detailed imaging of physiological and pathological anterior and posterior segment structures. As a multi-purpose device, it offers a wide spectrum of applications, with high-quality OCT-imaging, in a comfortable setting without the need to move the patient.
  Current eye research 08/2010; 35(8):722-32. · 1.51 Impact Factor
• Article: Intravital multidimensional real-time imaging of the conjunctival immune system.

  U Gehlsen, G Hüttmann, P Steven
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  ABSTRACT: The conjunctiva, as a peripheral mucosal surface, is dependent on the migration of immune cells to facilitate an orchestrated immune response. So far, only limited data to visualize these dynamics directly have been obtained, mainly due to technical and experimental restrictions. To investigate migration on a cellular level, the following conditions need to be met: (1) intravital investigations need to be facilitated by suitable microscopic techniques; (2) tissues need to be investigated in three spatial dimensions and over time; (3) data need to contain detailed information about the tissue character. Whereas the use of confocal laser scanning microscopy allows high-resolution imaging of the superficial conjunctival immune system and enables the recording of rapid cellular migration, intravital two-photon microscopy further enables tracking of individual cells and characterization of cells and structures with unique optical features using autofluorescence detection, fluorescence lifetime measurements and second harmonic generation in deep tissue. Based on current results and experimental studies, two-photon microscopy has the potential for general use in basic research and clinical practice, and would greatly enhance possibilities for diagnosing and analyzing inflammatory processes of the ocular surface. In particular, inflammation in common diseases, such as allergy and dry eye, and its progress under treatment could be investigated in detail.
  Developments in ophthalmology 01/2010; 45:40-8.
• Article: [Optical coherence tomography: from retina imaging to intraoperative use - a review].

  G Hüttmann, E Lankenau, C Schulz-Wackerbarth, M Müller, P Steven, R Birngruber
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  ABSTRACT: Optical coherence tomography (OCT) is new diagnostic procedure that has rapidly evolved in the last years. The recently developed spectral domain OCT allows one to increase the imaging speed by a hundred times compared to the first generation time domain OCT and enables three-dimensional imaging as well as real-time imaging of fast moving structures. Volumetric imaging improves the quantitative measurement of morphology and the evaluation of temporal changes. In addition, an exact correlation with images acquired with other imaging modalities is possible. Real-time imaging enables also the use of OCT during examinations with the slit-lamp and during ophthalmological surgery. A spectral domain OCT was adapted to a slit lamp. 70 patients (91 eyes) were examined at the anterior or posterior segment of the eye. Images of healthy structures and different pathologies were compared to OCT images obtained with Stratus 3, Spectralis, and the SL-OCT. To demonstrate the feasibility of OCT during surgery, spectral domain OCT devices working with 20,000 and 210,000 A scans per second were coupled by specially developed optics to the camera port of a surgical microscope. The device was tested with phantoms and enucleated pig eyes. A 5 kHz spectral domain OCT can image the retina during slit lamp-based indirect ophthalmoscopy with a quality similar to that of the Stratus 3. In addition, relevant structures of the anterior segment were imaged. Here, compared to commercially available devices, the imaged field was smaller and the angle of the anterior chamber was not directly visible due to the 830 nm wavelength, which had to be used for retinal imaging. Through the surgical microscope, a volumetric imaging of epithelium, Bowman's, Descemet's membranes, limbus, iris, lens, conjunctiva and sclera was demonstrated with several tens of centimetre working distance. Instruments and incisions in the cornea were visualised with 20 microm precision. Real-time imaging and visualisation of volumetric OCT data were also demonstrated. In principle, all technical problems of an intraoperative use of OCT have been solved and a clinical trial will start in the near future. OCT has the potential to improve the precision of surgical interventions and may even enable new interventions.
  Klinische Monatsblätter für Augenheilkunde 12/2009; 226(12):958-64. · 0.51 Impact Factor
• Article: Übersicht der apparativen Entwicklungen in der optischen Kohärenztomografie: von der Darstellung der Retina zur Unterstützung therapeutischer Eingriffe / Optical Coherence Tomography: from Retina Imaging to Intraoperative Use - a Review

  G. Hüttmann, E. Lankenau, C. Schulz-Wackerbarth, M. Müller, P. Steven, R. Birngruber
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  ABSTRACT: Background: Optical coherence tomography (OCT) is new diagnostic procedure that has rapidly evolved in the last years. The recently developed spectral domain OCT allows one to increase the imaging speed by a hundred times compared to the first generation time domain OCT and enables three-dimensional imaging as well as real-time imaging of fast moving structures. Volumetric imaging improves the quantitative measurement of morphology and the evaluation of temporal changes. In addition, an exact correlation with images acquired with other imaging modalities is possible. Real-time imaging enables also the use of OCT during examinations with the slit-lamp and during ophthalmological surgery. Methods: A spectral domain OCT was adapted to a slit lamp. 70 patients (91 eyes) were examined at the anterior or posterior segment of the eye. Images of healthy structures and different pathologies were compared to OCT images obtained with Stratus 3, Spectralis, and the SL-OCT. To demonstrate the feasibility of OCT during surgery, spectral domain OCT devices working with 20000 and 210000 A scans per second were coupled by specially developed optics to the camera port of a surgical microscope. The device was tested with phantoms and enucleated pig eyes. Results and Conclusions: A5 kHz spectral domain OCT can image the retina during slit lamp- based indirect ophthalmoscopy with a quality similar to that of the Stratus 3. In addition, relevant structures of the anterior segment were imaged. Here, compared to commercially available devices, the imaged field was smaller and the angle of the anterior chamber was not directly visible due to the 830 nm wavelength, which had to be used for retinal imaging. Through the surgical microscope, a volumetric imaging of epithelium, Bowman’s, Descemet’s membranes, limbus, iris, lens, conjunctiva and sclera was demonstrated with several tens of centimetre working distance. Instruments and incisions in the cornea were visualised with 20 µm precision. Real-time imaging and visualisation of volumetric OCT data were also demonstrated. In principle, all technical problems of an intraoperative use of OCT have been solved and a clinical trial will start in the near future. OCT has the potential to improve the precision of surgical interventions and may even enable new interventions.
  Klinische Monatsblätter für Augenheilkunde 01/2009; 226(12):958-964. · 0.51 Impact Factor
• Article: [Bilateral pigmented epi- and submacular membrane].

  P Steven, M Klinger, H Hoerauf
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  ABSTRACT: The aim of this communication is to report a case of epiretinal membrane removal with intra-operative unexpected subretinal extension of the membrane. This is an observational case report. An 83-year-old female patient with bilateral pigmented secondary macular pucker after laser coagulation for diabetic retinopathy underwent vitrectomy with membrane peeling and membrane excision. The specimen was studied by means of light and electron microscopy. The pigmented membrane extended through the retina forming an epiretinal and an intraretinal portion. Electron microscopy revealed connective tissue, capillaries and two different cell types that were retinal pigment epithelium-like and fibroblast-like. Misinterpreted parafoveal telangiectasis and focal lasercoagulation is the likely cause for our findings.
  Klinische Monatsblätter für Augenheilkunde 04/2008; 225(3):240-2. · 0.51 Impact Factor
• Article: [Current state of mechanical corneal surgery - results of a questionnaire to members of the cornea section of the German Society of Ophthalmologists].

  P Steven, R Winter, G Geerling
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  ABSTRACT: The aim of this study was to obtain an overview on the surgical and the perioperative management strategies involved in mechanical corneal surgery in Germany, Switzerland and Austria. A questionnaire was sent to 60 ophthalmological hospitals. Within one year the responding centres (n = 48) performed 3171 penetrating and 166 lamellar keratoplasties, 224 limbal stem cell--and 817 amniotic-membrane transplantations. In high-risk cases, 33 % of the centres did not use HLA-matched grafts. Predominantly manual trephine systems were used. Of the responding institutions 96 % used 10.0 nylon sutures and 64 % used a double running anti-torque technique for normal-risk keratoplasty. In tectonic and high-risk keratoplasties, interrupted sutures were used predominantly (70 % and 56 %). Suture removal was performed between one month (first suture) and up to 36 months (last suture) postoperatively. Procedures considered to be standard--such as penetrating keratoplasty--are performed with numerous and significant technical variations. The likely influence of such variations on the long-term outcome should be further evaluated.
  Klinische Monatsblätter für Augenheilkunde 11/2006; 223(10):844-8. · 0.51 Impact Factor
• Article: Secondary paracentral retinal holes following internal limiting membrane removal.

  P Steven, H Laqua, D Wong, H Hoerauf
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  ABSTRACT: To report on a new postoperative finding after delamination of the internal limiting membrane (ILM) for the treatment of different macular pathologies. Seven patients are described with paracentral retinal holes, all located temporally to the macula, which developed after pars plana vitrectomy and uncomplicated ILM removal for cystoid macular oedema (n = 3), macular pucker (n = 3), and macular hole (n = 1) with the use of indocyanine green (n = 4), trypan blue (n = 1), triamcinolone acetonide (n = 1), or without dye (n = 1). The use of dyes has been incriminated in causing iatrogenic damage to the retina. In this series, the new observation of retinal holes in the macular area is thought to be related to the removal of the ILM itself. The authors speculate that ILM delamination may cause a retinal weakening by Müller cell damage; this may be followed by a structural breakdown and, consequently, hole formation.
  British Journal of Ophthalmology 04/2006; 90(3):293-5. · 2.90 Impact Factor
• Article: Distribution of TFF peptides in corneal disease and pterygium.

  P Steven, G Schäfer, B Nölle, M Hinz, W Hoffmann, F Paulsen
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  ABSTRACT: The central cornea of 10 cadavers and 33 patients suffering from keratoconus, herpetic keratitis, Fuchs' dystrophy and pterygium were analysed focusing on the expression of TFF peptides by means of reverse transcription polymerase chain reaction and immunohistochemistry. TFF1 and TFF3 transcripts were detected in healthy corneae as well as in pterygia. Only TFF3 mRNA was transcribed in keratoconus, Fuchs' dystrophy and herpetic keratitis. Immunohistochemistry revealed absence of all three TFF peptides in healthy corneae but production of TFF3 in each of the diseased corneae. In pterygia both TFF1 and TFF3 synthesis was detectable in goblet cells. The absence of TFF peptide production in the healthy cornea indicates that TFF3 secretion is induced in different corneal diseases by yet unknown stimuli. Here TFF3 synthesis can be interpreted as a protection mechanism, because all corneal diseases analysed are characterized by progressive tissue destruction. TFF1 and TFF3 production by goblet cells in pterygia is comparable to the healthy conjunctiva suggesting that TFF peptides do not play a significant role in the pathogenesis of pterygia.
  Peptides 06/2004; 25(5):819-25. · 2.43 Impact Factor
• Article: Orcein-picroindigocarmine--a new multiple stain.

  P Steven, F Paulsen, B Tillmann
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  ABSTRACT: A new "orcein-picroindigocarmine staining", a colour combination of orcein, indigo carmine, and picric acid, was developed for histological applications. The new technique was tested on different human tissues. Colours ranging from red to brown, yellow, green and blue were observed in paraffine sections of tissues stained by this method. Nuclear structures in all tissues were stained dark brown to dark blue. Squamous epithelium was stained light brown with varying shades of blue in upper horny layers, whereas the ciliated epithelium was tinged blue grey. When connective tissue was stained, collagen fibrils appeared strongly blue next to elastic fibres, which took on a rust brown tinge; cellular components were all coloured brown. The matrix of hyaline cartilage was stained in different shades of blue, with the chondrocytes rust brown. Sections of bone components appeared dark blue to dark green. Skeletal muscle cells were coloured yellow and green with blue collagenous septa. The new staining is useful for distinguishing connective tissue components such as elastic fibres and collagen fibrils. It also demonstrates chondrocytes in favourable contrast to the cartilage matrix. The technique produces aesthetic staining colouring that could supplement histological investigations and provide an alternative to other staining materials.
  Archives of Histology and Cytology 11/2000; 63(4):397-400. · 0.57 Impact Factor