Biomedical subjects

Joachim Stave

Publications and source records attributed to Joachim Stave.

11 recordsLinked to original sources

PubMed2007

In vivo confocal microscopic evaluation of langerhans cell density and distribution in the corneal epithelium of healthy volunteers and contact lens wearers.

PURPOSE: To examine and compare the density and distribution of Langerhans cells (LCs) in the corneal epithelium of healthy volunteers and contact lens wearers. METHODS: A total of 225 eyes of 130 healthy volunteers (age, 17-81 years) without history of ocular inflammation, trauma, or surgery and 98 eyes of 55 contact lens wearers (age, 13-76 years) were examined in vivo with the combination of the Heidelberg Retina Tomograph II and in-house-invented Rostock Cornea Module. RESULTS: In healthy volunteers, in vivo confocal microscopy revealed LCs in 31% of all volunteers, with 37 of these 43 volunteers presenting LCs both in the center and the periphery of the cornea with densities of 34 +/- 3 and 98 +/- 8 cells/mm, respectively. In the group of contact lens wearers, 55% of all corneas presented with LCs, and 11 of these 33 corneas revealed LCs at central and peripheral locations. Although LC densities were markedly higher in both the central (78 +/- 25 cells/mm) and the peripheral cornea (210 +/- 24 cells/mm) of contact lens wearers, the gradient of LC density from peripheral to central cornea was found almost identical in both groups. In the central cornea, LC density decreased with duration of contact lens wear. LCs were located at the depth of 35 to 60 microm (ie, the level of lower intermediate cells, basal cells, and subepithelial nervous plexus). LCs presented as either large cells bearing long processes or smaller cells lacking cell dendrites, most supposedly indicating mature and immature phenotype, respectively. CONCLUSIONS: In vivo confocal microscopy enables evaluation of LC density and distribution in corneal epithelium. LCs were found present both in the center and the periphery of the cornea without difference in distribution between healthy volunteers and contact lens wearers. However, contact lens wearers revealed almost twofold higher LC densities in both locations, implying chronic mechanical irritation of the cornea in response to the contact lens as foreign body. Taken together, analysis of LC using in vivo confocal microscopy provides helpful information for a better understanding of contact lens-disturbed ocular homeostasis.

Adolescent↗

PubMed2006

In vivo three-dimensional confocal laser scanning microscopy of the epithelial nerve structure in the human cornea.

PURPOSE: Evaluation of a new method for in vivo visualization of the distribution and morphology of human anterior corneal nerves. METHOD: The anterior cornea was examined to a depth of 100 microm in four human volunteers with a confocal laser scanning microscope (CLSM) using a Rostock Cornea Module (developed in house) attached to a Heidelberg Retina Tomograph II (Heidelberg Engineering, Germany). Optical sections were digitally reconstructed in 3D using AMIRA (TGS Inc., USA). The scanned volumes had a greatest size of 300 x 300 x 40 microm and voxel size of 0.78 x 0.78 x 0.95 microm. RESULTS: The spatial arrangement of the epithelium, nerves and keratocytes was visualized by in vivo 3D-CLSM. The 3D-reconstruction of the volunteers' corneas in combination with the oblique sections gave a picture of the nerves in the central human cornea. Thin nerves run in the subepithelial plexus aligned parallel to Bowman's layer and are partially interconnected. The diameter of these fibres varied between 1.0 and 5 microm. Thick fibres rose out of the deeper stroma. The diameter of the main nerve trunks was 12+/-2 microm. Branches penetrating the anterior epithelial cell layer could not be visualized. CONCLUSIONS: 3D-CLSM allows analysis of the spatial arrangement of the anterior corneal nerves and visualization of the epithelium and keratocytes in the living human cornea. The developed method provides a basis for further studies of alterations of the cellular arrangement and epithelial innervation in corneal disease. This may help to clarify alterations of nerve fibre patterns under various clinical and experimental conditions.

Adult↗

PubMed2006

In vivo confocal microscopy of the ocular surface.

Over the past two decades, the applications of in vivo confocal microscopy to the investigation of ocular surface diseases in the living eye have been greatly extended. Confocal microscopy enables detailed investigation of tarsal and palpebral conjunctiva, central and peripheral cornea, tear film, and lids, and it allows evaluation of the ocular surface at the cellular level. High-quality imaging in both contact and noncontact modes has allowed new understanding of the functions of the ocular surface system, and in the coming years, such knowledge will become increasingly comprehensive and specific. Confocal microscopy may provide a link between well-established ex vivo histology and in vivo study of ocular pathology, not only in clinical science but also in clinical practice. The purpose of this review is to summarize the current knowledge about in vivo confocal microscopy of the ocular surface.

Conjunctiva↗

PubMed2006

In vivo investigations of the corneal epithelium with the confocal Rostock Laser Scanning Microscope (RLSM).

BACKGROUND: The confocal tandem scanning microscope was first used in 1985 by Lemp et al for in vitro and in 1990 by Cavanagh et al for in vivo investigation of human eyes. The aim of this study was to investigate the cells of the central and the peripheral portions of the corneal epithelium and to measure corneal epithelium thickness and the total thickness of the corneas of our volunteers with the new Rostock Laser Scanning Microscope. MATERIAL AND METHODS: A Heidelberg Retina Tomograph (HRT II) was used in combination with a water contact microscope lens (Zeiss, x63, 0.95), the Rostock cornea module (RCM) developed at our institute for the in vivo examination of the cornea. In this study, 92 eyes of 68 subjects between the ages of 15 and 88 years were examined. RESULTS: At the superficial cell layer, the average cell density in the central cornea was 840 +/- 295 cells/mm2, and in the periphery it was 833 +/- 223 cells/mm2. At the wing cell layer, the average cell density rises to 5070 +/- 1150 cells/mm2 in the central and to 5582 +/- 829 cells/mm2 in the peripheral cornea. At the basal cell layer, the cell density rises further to 8996 +/- 1532 cells/mm2 in the central and 10,139 +/- 1,479 cells/mm2 in the peripheral corneal epithelium. The average corneal thickness in the central region was found to be 545 +/- 25 microm, and 652 +/- 75 microm in the periphery. The average epithelium thickness was determined centrally to be 54 +/- 7 microm, and peripherally 61 +/- 5 micrim. CONCLUSIONS: The Rostock Scanning Laser Microscope offers a standardized, reproducible, safe, and fast diagnostic procedure for the evaluation of the corneal epithelium. This technology allows better image quality compared with confocal-slit scanning microscopes and produces a precise depth measurement.

Adolescent↗

PubMed2006

Laser scanning microscopy of the human larynx mucosa: a preliminary, ex vivo study.

OBJECTIVE: Laser scanning microscopy (LSM) supplies in vivo information from epithelia up to depths between 0.1 to 0.5 mm. The aim of this ex vivo prospective pilot study was to investigate the potential use of LSM for the diagnosis of laryngeal cancer and its precursors. METHODS: Forty-three larynx specimens of 26 patients (age 35-61 years, mean age 51.9+/-9.5 years; 7 women and 19 men) with laryngeal lesions were investigated with LSM. The LSM findings were compared with histopathologic sections. The following criteria were used for characterization of cancerous lesions: enlarged nuclei, enlarged cells with variable shapes, cluster of cells, increased nucleus/cytoplasm ratio, irregular cell architecture, and loss of cellular junctions characterized by lack of visualization of the cell membrane. RESULTS: LSM enables the visualization of epithelium up to the basement membrane, Reincke space, the subepithelial vessels, and the fibers of the subepithelial space. In contrast to the squamous epithelium, the respiratory epithelium bears kinocilia. The beat of the cilia and the directed mucous transport can be observed ex vivo. With the use of the presented malignancy criteria, a sensitivity of 72.7% and a specificity of 82.9% for differentiation of dysplasia and benign laryngeal lesions from cancer were reached. CONCLUSIONS: LSM in an ex vivo manner supplies microscopic images up to the subepithelial space. LSM could represent a new technology in laryngology to visualize larynx epithelia. In the next step, in vivo LSM will be applied to evaluate laryngeal lesion in vivo.

Adult↗

PubMed2005

In vivo confocal microscopic evaluation of Langerhans cell density and distribution in the normal human corneal epithelium.

PURPOSE: To examine the density and distribution of Langerhans cells (LCs) in the corneal epithelium of healthy volunteers. METHODS: Two hundred eyes of 112 healthy volunteers (age 21-81 years) without history of ocular inflammation or surgery were examined in vivo with the combination of the Heidelberg Retina Tomograph II and the Rostock Cornea Module. For statistical analysis data of one eye per volunteer were used, with random selection of one eye in those volunteers in whom both eyes were studied. RESULTS: As studied by in vivo confocal microscopy, 31.3% of all volunteers presented with LCs (24 volunteers with both eyes studied and 11 volunteers with only one eye studied). In 30 of these 35 volunteers, LCs were found in both the central and peripheral corneal epithelium. More than 50% of male volunteers with LCs were younger than 30 years; in contrast, almost two thirds of females with LCs were above 50 years in age. The density of LCs in the periphery of the cornea (98+/-8 cells/mm2; range 0-208 cells/mm2) was significantly (p<0.001) greater than in the central part (34+/-3 cells/mm2; range 0-64 cells/mm2). LCs were located at depths of 35-60 microm, with different frequency. While LCs were sparse at the level of deep intermedial cells (5.7% of the volunteers), 11.4% of the volunteers presented with LCs within the level of basal epithelial cells and most of the eyes (82.9%) had LCs at the level of basal epithelial cells and subbasal nerve plexus. Moreover, LCs presented as either large cells bearing long processes or smaller cells lacking cell dendrites, presumably indicating mature and immature phenotype, respectively. CONCLUSION: The Heidelberg Retina Tomograph II in combination with the Rostock Cornea Module enables in vivo assessment of density and distribution of LCs in the corneal epithelium, providing insight into human eye immunology. These data may now provide a suitable basis for further investigations in ocular pathology.

Adult↗

PubMed2005

In vivo observation of papillae of the human tongue using confocal laser scanning microscopy.

The aim of this investigation was to visualize the epithelial structures of the tongue using confocal laser scanning microscopy (LSM). The human tongue epithelium of 28 healthy subjects, aged 21-67 years, mean age 38 years, 14 women and 14 men, was examined in vivo by LSM. Using LSM, a combination of the Heidelberg Retina Tomograph HRT II and the Rostock Cornea Module, up to 800-fold magnifications were obtained. On the tongue surface both filiform and fungiform papillae and their taste pores were easily identified. The epithelium of the tongue with its subcellular structures could be observed up to a depth of 50 microm, cellular structures up to 150 microm and subepithelial vessels up to 300 microm. Additionally the papillary crests and blood flow were visible. Confocal LSM seems suitable for noninvasive in vivo examination of the tongue. The hydraulic z scan, the manual start setting and the measurement of the depth allow a clear classification of the observed structures.

Adult↗

PubMed2002

Monitoring accommodative ciliary muscle function using three-dimensional ultrasound.

BACKGROUND: Our objective was to develop a three-dimensional high-resolution ultrasonic imaging technique to be utilized for in-vivo characterization of the ciliary body and the posterior iris. The benefit of this imaging in enhancing the quantification of the configurational changes in the ciliary body during accommodation is demonstrated. METHODS: Sequential ultrasound biomicroscopic images of the ciliary body region were obtained with a computer-controlled scanning device designed for use with a standard ultrasound biomicroscope for 3D imaging. Custom-made software allows online data collection, data analysis and 3D reconstruction in conjunction with commercially available VoxelView software. RESULTS: The three-dimensional presentation allows a close approximation of the ciliary muscle inside the ciliary body in vivo. We are able to distinguish and to analyze the changes in the muscle contour in different accommodation states. During accommodation a shift in the ciliary muscle center of gravity in a range of 0.04-0.26 mm (mean 0.13+/-0.06 mm) in the direction of the lens equator, with an interindividual variation and a small decrease with age, was observed. CONCLUSIONS: High-resolution ultrasound is a well established technique for in-vivo investigation of the anterior segment. Three-dimensional ultrasound biomicroscopy allows an assessment of the individual ciliary muscle activity in consideration of the ciliary processes. In combination with a contour analysis tool we improved the muscle contour determination during different accommodation states. The investigation showed an activity of the ciliary muscle in young volunteers as well as those of presbyopic age.

Accommodation, Ocular↗

PubMed2002

Depth and age-dependent distribution of keratocytes in healthy human corneas: a study using scanning-slit confocal microscopy in vivo.

PURPOSE: To document keratocyte distribution and changes with age in the cellular network of the human cornea in vivo. SETTING: Department of Ophthalmology, University of Rostock, Rostock, Germany. METHODS: Forty-nine eyes of 31 healthy subjects of various ages were examined with a modified Microphthal scanning-slit confocal microscope (SSCM) (Hund) to document keratocyte distribution in the intact living cornea. Optical sections made by confocal microscopy were recorded on videotape, and the keratocyte density was determined for the total volume of the cornea and for the stromal sublayers. RESULTS: The highest cell density was in the anterior stroma of the cornea immediately posterior to Bowman's membrane (24 320 cells/mm(3) +/- 6740 [SD]), the lowest in the central area (11,610 +/- 4290 cells/mm(3)), and an intermediate density in the posterior stroma immediately adjacent to Descemet's membrane (18,850 +/- 4610 cells/mm(3)). The differences were statistically significant (P <.005). The keratocyte density was significantly lower in the anterior and posterior regions in the group older than 50 years: Cell density at 4% depth was 20,960 +/- 8200 cells/mm(3) and at 96%, 15 520 +/- 4290 cells/mm(3) (P <.05). CONCLUSIONS: In healthy living corneas, the keratocyte density was high in the areas adjacent to Bowman's and Descemet's membranes and was lower in patients older than 50 years than in those younger than 50 years. Further studies are needed to document the rate of change with age and to better understand the role and capacity of aging keratocytes in regenerative processes following corneal diseases or surgical procedures.

Adult↗

PubMedDate not supplied

[Prof. Carl Wilhelm von Zehender (1819-1916)--first professor of ophthalmology and co-founder of the ophthalmological clinic at the University of Rostock--commemorative lecture at the 100th DOG meeting in Berlin from 26.9 to 29.9.2002].

The Grand-ducal University Eye Department in Rostock was solemnly inaugurated 16 May 1892. According to many years of studies in Europe and on efforts to build this clinic, construction was outlined by Professor Carl Wilhelm v. Zehender, but the drafts were executed by the "Grossherzoglich-Mecklenburgisch-Schwerinschen Medicinalcommission" and Landbaumeister Schlosser in winter 1888/89. Professor v. Zehender, who originated from a very ancient Swiss family, was born in Bremen, 21 May 1819. He studied medicine in Goettingen, Jena, Prague, Paris and Vienna. During this time he developed a lifelong friendship with Albrecht v. Graefe. 1856 he took over the medical care for the hereditary duke Georg von Mecklenburg-Strelitz and published the "Correspondenzblatt für Aerzte im Grossherzoglichen Mecklenburg-Strelitz". 1857, during a conference in Heidelberg, his initiative led in the long run to the establishment of the "Heidelberger Ophthalmologische Gesellschaft", the forerunner of the "Deutsche Ophthalmologische Gesellschaft", which was founded in 1920. In 1863 the first edition of "Klinische Monatsblaetter für Augenheilkunde" was published as a periodical; the cover page bore its name as the founder of the magazine. In 1866, after the death of the hereditary duke and a professorship in his hometown Berne, he became honorary professor of the Rostock University, and from 1869 onwards he chaired the clinic as a regular professor. After all his efforts to build his own hospital had failed, he demonstratively and finally resigned from his professorship in 1889. He went to Munich and became editor of the " Klinische Monatsblaetter für Augenheilkunde". In 1907 he moved with his wife via Eutin to Warnemuende. There the nestor of world ophthalmologists died at the age of 98. His burial place without gravestone is situated in today's landscape park "Stephan Jantzen". So far all efforts of the author and of the Rostock University Eye Department taken after 1980 to create a worthy note to this exceptional ophthalmologist in the Baltic Sea resort Warnemuende were unsuccessful, also for financial reasons. But on 2.9.2002 with the help of the Lighthouse Club of Warnemuende a memorial plaque to Prof. C. W. v. Zehender was mounted on the guest house "Margarete". This plaque commemorates Professor Zehender's merits in establishing the DOG, planning and building the eye clinic of the university of Rostock.

Germany↗

PubMedDate not supplied

Potentially accommodating intraocular lenses--an in vitro and in vivo study using three-dimensional high-frequency ultrasound.

PURPOSE: To investigate the accommodative performance of new intraocular lenses (IOL) using the advantages of three-dimensional ultrasound biomicroscopy. METHODS: An in vitro simulation device was designed to study IOL performance using an artificial capsular bag and a stretching device. The haptic region of the Akkommodative 1CU (HumanOptics AG) and CrystaLens AT-45 (Eyeonics Inc) was visualized in vitro in three dimensions, using an in-house developed three-dimensional ultrasound biomicroscope. The in vitro results were used to describe the in vivo situation in four patients with accommodative implants. RESULTS: The haptic position and angulation in consideration of the accommodation state was distinguished and analyzed. In the simulation model, a maximal angulation change of 4.5 degrees and 4.3 degrees and a maximal forward shift of 0.33 mm and 0.28 mm was observed for the AT-45 and 1CU, respectively. In vivo, a change in haptic angulation <100 and a maximal forward shift of 0.50 mm was observed for the 1CU. These changes correspond to a theoretical approximate value of 0.50 diopters. CONCLUSIONS: The in vitro simulation device examined with three-dimensional ultrasound biomicroscopy provided information on the accommodative performance of these potentially accommodative IOL designs. Using three-dimensional ultrasound biomicroscopy, corresponding changes in haptic angulation during pharmacological-induced accommodation were observed.

Accommodation, Ocular↗