Search PubMed⌕ Search

Biomedical subjects

Anselm Kampik

Publications and source records attributed to Anselm Kampik.

At least 55 records · Page 3Linked to original sources
PubMed2005

Bilateral recurrent calcareous degeneration of the cornea.

PURPOSE: To report clinical, histologic, and electron microscopic findings in several consecutive keratoplasties with recurrent pancorneal calcification in a patient with chronic graft versus host disease and severe keratoconjunctivitis sicca following bone marrow transplantation for chronic myelogenous leukemia. METHODS: Altogether 5 penetrating keratoplasties were performed in both eyes for descemetocele formation and corneal perforation as well as pancorneal calcification associated with severe visual loss. Histologic examination and electron microscopy were performed on the corneal buttons obtained. RESULTS: Histology and electron microscopy confirmed pancorneal extracellular calcium deposition with increasing severity in each consecutive keratoplasty. Calcification was associated with necrosis and inflammation of the corneal stroma. Clinically unsuspected fungal keratitis was observed in 1 specimen. CONCLUSIONS: Keratoconjunctivitis sicca, epithelial defects, corneal inflammation, and infection are most probably responsible for the recurrent pancorneal calcification seen in our patient. The role of cytokines in this complication is discussed.

Adult↗
PubMed2005

Histology of the vitreoretinal interface after indocyanine green staining of the ILM, with illumination using a halogen and xenon light source.

PURPOSE: To assess the histology of the retinal surface after staining of the inner limiting membrane (ILM) with indocyanine green (ICG) followed by illumination with halogen or xenon light sources in human donor and porcine eyes. METHODS: Ten eyes of six human donors and six porcine eyes were used in the study. In human donor eyes, the postmortem time varied between 7 and 38 hours, and porcine eyes were evaluated 9 hours after death. In all eyes, the vitreous was removed, and a few drops of 0.5% ICG were poured over the trephined posterior pole and carefully washed out after a period of 1 minute, with balanced salt solution. Then the stained retina was illuminated for 3 minutes with different light sources: a halogen light source of 145-W power or a xenon light source of 50-W power. Adjacent, unstained retina of each eye served as a control to assess postmortem artifacts. In two human and two porcine eyes ICG was applied without illumination. Retinal specimens were evaluated by light and electron microscopy. RESULTS: In human eyes, severe disorganization of the innermost retina and ILM loss were observed after ICG application with subsequent illumination with the halogen light source. After illumination with the xenon light source, there was only slight vacuolization of the innermost retina, with mostly intact Muller cells. The ILM remained in situ in relation to the retinal surface. Intact cellular architecture was found in all specimens after ICG staining without subsequent illumination and control specimens of unstained retina. In porcine eyes, no impact attributable to the light source or ICG alone was noted in this experimental setting. CONCLUSIONS: These findings suggest that adverse effects of ICG at the retinal surface may depend on the light source used during vitrectomy and correlate with the emission spectrum of the different light sources. In addition, care should be taken when comparing results obtained in human eyes and porcine eyes.

Adolescent↗
PubMed2005

An evaluation of novel vital dyes for intraocular surgery.

PURPOSE: To evaluate systematically the staining characteristics and safety of potential new dyes for intraocular surgery. METHODS: Six dyes were included in the investigation: light green SF (LGSF) yellowish, E68, bromophenol blue (BPB), Chicago blue (CB), rhodamine 6G, rhodulinblau-basic 3 (RDB-B3). All dyes were dissolved and diluted in a balanced saline saline solution. The light-absorbing properties of each dye were measured at a concentration of 0.05% between 200 and 1000 nm. Staining characteristics were examined by staining lens capsule tissue and epiretinal membranes (ERMs), removed intraoperatively, with dye concentrations of 1.0%, 0.5%, 0.2%, and 0.05%. Enucleated porcine eyes (postmortem time, 9 hours) were also stained. Dye-related toxicity was evaluated by a colorimetric test (MTT) measuring the inhibition of retinal pigment epithelium (RPE) cell proliferation (ARPE-19 and primary human RPE cells, passages 3-6). Cell viability was also quantified based on a two-color fluorescence cell-viability assay. Dyes were investigated in concentrations of 0.2% and 0.02%. RESULTS: All dyes investigated in this study stained human lens capsules, removed intraoperatively; ERMs, peeled during macular pucker surgery; and enucleated porcine eyes, depending on the concentration applied. The long-wavelength absorption maximum of the dyes was within the range of 527 to 655 nm at concentrations of 0.05%. Rhodamine G6 and RDB-B3 showed adverse effects on ARPE-19 cell proliferation at a concentration of 0.2% and were excluded from further investigation in primary RPE cells. The remaining four dyes showed no toxic effect on ARPE-19 and primary RPE cell proliferation at concentrations of 0.2% and 0.02%. Cell viability was affected by LGSF yellowish (0.2%) and CB (0.2% and 0.02%). Two dyes (E68 and BPB) showed no relevant toxicity in vitro. CONCLUSIONS: The systematic evaluation of dyes for intraocular use seems mandatory. In this study four dyes were identified with effective staining characteristics, with two of these dyes having no detectable toxic effect on RPE cells in vitro.

Acridine Orange↗
PubMed2004

Intravitreal vancomycin and amikacin versus intravenous imipenem in the treatment of experimental Staphylococcus aureus endophthalmitis.

BACKGROUND: Controversy still surrounds the intravenous (IV) treatment of endophthalmitis. The purpose of this study was to compare IV and intraocular (IO) treatment in experimental Staphylococcus aureus endophthalmitis: intravitreal injection of vancomycin and amikacin (VA/AN) in comparison with IV imipenem (IPM) and a combination of IV and IO (IV+IO) therapy. METHODS: The right eyes of 27 rabbits were injected with 25000 S. aureus. After 24 h, animals were either treated with IO VA/AN ( n=5; 1.0 mg/0.4 mg in 0.1 ml saline), or IV IPM ( n=9; 37 mg/kg body weight 3x daily), or IV+IO therapy ( n=7), or served as untreated controls ( n=6). Clinical appearance was evaluated daily and vitreous aspirates were obtained for bacterial culture 24 h and 6 days after therapy, when the eyes were enucleated for histopathologic examination. RESULTS: Eyes in the IO or IO+IV treatment group had a significantly better appearance clinically and histologically than did eyes in the IV or untreated control group. Eyes in the IO+IV group had a similar appearance to the IO-treated eyes. All aspirates from the IO and IO+IV groups were culture-negative 24 hours after therapy, whereas only five of nine in the IV-treated group were culture-negative. Aspirates from all treatment groups were culture-negative by day 6 after the initiation of therapy. Untreated control eyes were culture-positive at all times. CONCLUSION: IO therapy with VA/AN proved more effective in treating experimental S. aureus endophthalmitis than did IV therapy with IPM alone. IV+IO treatment was not superior to IO treatment alone.

Amikacin↗
PubMed2004

Histopathological abnormalities in ocular blood vessels of CADASIL patients.

PURPOSE: To assess histopathological findings in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). DESIGN: Case reports and histopathological evaluation of enucleated eyes. METHODS: Four eyes from two CADASIL patients were enucleated at autopsy and prepared for histopathological analysis using light and electron microscopy. RESULTS: Thickening of arterial walls with fibrosis, eosinophilic Periodic acid Schiff-positive basement membrane material and loss of vascular smooth muscle cells (VSMC) in the central retinal artery and its branches, the leptomeninges, the ocular adnexa, and the optic disk were observed. On electron microscopy, numerous deposits of granular, osmiophilic material in arterial walls as well as VSMC and pericyte degeneration were noted. In contrast to retinal vessels, the choroid was not affected. CONCLUSION: Our findings suggest a differential involvement of small blood vessels in CADASIL, depending on the angioarchitecture and support autopsy data of nervous tissue describing that loss of VSMCs is most pronounced in tissues depending on blood-tissue barriers.

Bruch Membrane↗
PubMed2004

Functional outcome after trypan blue-assisted vitrectomy for macular pucker: a prospective, randomized, comparative trial.

PURPOSE: To evaluate functional outcome after the intraoperative application of 0.06% trypan blue during vitrectomy for macular pucker. DESIGN: Prospective, randomized, comparative study. METHODS: Forty-three eyes of 43 consecutive patients, 30 women and 13 men, were incorporated in the study. Patients were randomized into two groups: group 1 (n = 22) with trypan blue (0.06%) staining, and group 2 (n = 21) without trypan blue staining. Functional outcome (best-corrected visual acuity, Goldmann perimetry) was evaluated 1 day before surgery, at 6 weeks, and at intervals of 3, 6, and 12 or more months postoperatively. Only patients with an idiopathic macular pucker were included. In all patients, a standard three-port pars plana vitrectomy with peeling of an epiretinal membrane (ERM) and the internal limiting membrane was performed. No other modification of the surgical procedure, except the use of trypan blue was made between the two groups. RESULTS: Mean age was 68.9 years in group 1 (with trypan blue) and 69.4 in group 2 (without trypan blue). Median best-corrected visual acuity was 20/63 in both groups (range, 20/200-20/40; P >.5) before surgery. Mean follow-up time was 5.8 months in group 1 and 5.3 months in group 2. After surgery, median visual acuity had increased to 20/40 in both groups (range, 20/500 to 20/20 in group 1 and 20/100 to 20/20 in group 2; P <.001 for both groups). The difference between both groups was not statistically significant (P >.5). An improvement of visual acuity (gain of 2 or more lines) was seen in 16 patients of both groups. No postoperative visual field defects were noted. CONCLUSIONS: Trypan blue-assisted vitrectomy for macular pucker leads to good functional results with no dye-related adverse effects after short follow-up. Trypan blue might be especially applicable in cases in which the borders of the ERM are difficult to define. Hypothetical advantages, such as fewer recurrences of ERMs after trypan blue staining, will have to be evaluated during further follow-up of patients.

Aged↗
PubMed2004

Detection of laser in situ keratomileusis in a postmortem eye using optical coherence tomography.

With more individuals having laser in situ keratomileusis (LASIK), eye banks are challenged to detect prior refractive surgery in donor tissue. We report the case of a donor who had LASIK 9 months before his death. Slitlamp biomicroscopy, corneal topography, and optical coherence tomography (OCT) were performed to evaluate the corneas. Few changes were detected under slitlamp examination and corneal topography. We demonstrate that OCT is capable of detecting LASIK-induced structural changes in the immediate postmortem evaluation and during the early and late period of organ culture. We recommend OCT screening of potential donor corneas before organ culture and between days 9 and 12 of organ culture.

Cornea↗
PubMed2004

Histology of the vitreoretinal interface after staining of the internal limiting membrane using glucose 5% diluted indocyanine and infracyanine green.

PURPOSE: To evaluate the effect of indocyanine green (ICG) diluted with glucose 5% on the human retina in an experimental setting in postmortem eyes and during surgery for macular hole formation. DESIGN: Histopathological evaluation. METHODS: Possible adverse effects of two different solutions of 0.05% ICG (Pulsion, Munich, Germany; and Infracyanine, Laboratoire SERB, Paris, France) diluted with glucose 5% were evaluated in four eyes of two donors. In one eye of each donor, the ICG-stained macula was illuminated with 380 to 760 nm using the light source of a commonly used vitrectomy machine. In the other eye, ICG was applied to the macula without illumination. The retinal specimens were evaluated using light- and electron microscopy. Additionally, the ultrastructure of the internal limiting membrane (ILM) of four eyes that underwent ICG-assisted vitrectomy for macular hole formation was examined. RESULTS: In the postmortem study, both solutions of ICG caused significant morphologic alterations of the inner retina after light exposure. There was disorganization of the inner retina and complete loss of ILM after application of the dye and illumination. In contrast, no abnormalities were found after application of the dye without illumination and in unstained control specimens. No differences were noted between the two ICG products. Specimens of the ILM harvested during vitrectomy revealed cellular elements adjacent to the retinal side of the ILM. CONCLUSIONS: Staining of the ILM using ICG diluted in glucose 5% followed by illumination might induce an adverse effect on the inner retina and may result in an alteration of the cleavage plane from the ILM to the innermost retinal layers.

Adult↗
PubMed2004

Laser in situ keratomileusis in human corneas: new organ culture model.

PURPOSE: To establish an in vitro model of laser in situ keratomileusis (LASIK) in human donor eyes and to test its validity in comparison with animal models. SETTING: Department of Anatomy, Friedrich-Alexander Unviersity, Erlangen, Germany. METHODS: Laser in situ keratomileusis was performed on 20 organ-cultured human corneal buttons. The excimer laser ablations ranged from 0 to 12.0 diopters. The corneas were maintained in culture for up to 6 months and then evaluated with light microscopy and transmission electron microscopy. In addition, corneal sections were immunohistochemically stained for collagen type III, laminin, and fibronectin. The main outcome measures were the ultrastructural and immunohistochemical features of the stromal incision interface. RESULTS: Ultrastructural investigations in the peripheral cornea revealed a disarrangement of collagen fibers, indicating scar formation. These findings were not observed in the central area. Immunohistochemical staining for fibronectin and collagen type III was detected over the entire stromal incision interface, whereas laminin staining was related to the ingrowth of epithelial cells. CONCLUSIONS: The morphological changes after LASIK in an organ culture model can simulate the in vivo situation. Therefore, this model appears appropriate to use in further study of corneal wound-healing changes after LASIK.

Adult↗
PubMed2004

Trypan blue in macular pucker surgery: an evaluation of histology and functional outcome.

PURPOSE: To evaluate possible adverse effects of trypan blue on the ultrastructure of the human retina, to report on functional outcome of macular pucker surgery with and without the use of trypan blue, and to evaluate the ultrastructure of tissue harvested during surgery. DESIGN: Experimental study and prospective matched-pair analysis of two consecutive, interventional case series. METHODS: Possible adverse effects on the ultrastructure of the human retina by trypan blue were evaluated in three donor eyes in an experimental study using trypan blue in concentrations of 0.02%, 0.15%, and 0.25%. The retinas were histologically evaluated. In the clinical study, the functional outcome (visual acuity, Goldmann perimetry) of 10 eyes of 10 consecutive patients with intraoperative use of trypan blue (0.15%) was analyzed (group 1) and compared with the functional outcome in a matched group of patients (preoperative visual acuity, pre- and postoperative lens status) who had undergone vitrectomy without trypan blue assistance (group 2). Only patients with an idiopathic macular pucker were included. Epiretinal tissue of all eyes was harvested and prepared for ultrastructural analysis using light and electron microscopy. RESULTS: In the postmortem study, no significant alterations of the inner retina suggesting adverse effects of trypan blue concentrations of 0.02% were observed. In contrast, a disorganization of the innermost retina and an absence of the internal limiting membrane (ILM) was seen after the application of undiluted 0.15% and 0.25% trypan blue. In the clinical study, the median best-corrected visual acuity was 20/50 in both groups (range, 20/200-20/40) before surgery. Mean age was 70 years in group 1 (with trypan blue) and 69 years in group 2 (without trypan blue). Mean follow-up time was 4 months in group 1 and 5.6 months in group 2. Postoperatively, median visual acuity had increased to 20/32 (range, 20/100-20/25; Wilcoxon test P = 0.01) in group 1 and to 20/40 (range, 20/100-20/25; P = 0.09) in group 2. The difference between the two groups was not statistically significant (P = 0.4). Four of 10 patients without and 7 of 10 patients with trypan blue staining experienced an improvement of visual acuity (gain of 2 lines or more). No postoperative visual field defects were noted in either group. Histologic analysis of tissue harvested intraoperatively revealed the regular picture of undisturbed fibrocellular membranes. In some specimens, a layer of interspersed collagen was noted between epiretinal cells and the ILM, suggesting two different morphologic types of macular pucker. In a few sections, areas of cellular elements were detected adjacent to the retinal surface of the ILM. CONCLUSION: Trypan blue in a concentration of 0.02% is not associated with morphologic alterations of the inner retinal layers in our postmortem study. After application of 0.15% and 0.25% trypan blue solutions, a disorganization of the inner retinal layers was observed; the ILM was absent. We did not find any adverse effects of an intraocular trypan blue concentration of 0.02% on functional status. Our study further indicates that the functional results of surgery with and without the use of trypan blue are comparable. As the question of toxicity of a dye can not be answered by morphological observations alone, further experimental studies will be needed.

Adult↗
PubMed2004

TGF-beta2-induced cell surface tissue transglutaminase increases adhesion and migration of RPE cells on fibronectin through the gelatin-binding domain.

PURPOSE: Migration and adhesion of dislocated retinal pigment epithelial (RPE) cells to a fibronectin-rich extracellular matrix is an initial step in proliferative vitreoretinopathy (PVR). In the present study, the functional role of cell surface tissue transglutaminase (tTG) in adhesion and migration of RPE cells on fibronectin (Fn) and collagen type I (Col I) after stimulation with TGF-beta2 was investigated. METHODS: Cultured human RPE cells were treated with 1.0 ng/mL TGF-beta2 for 24 hours. Cell surface tTG expression was determined by cell fraction analysis. Attachment on Col I, full-length Fn, and its 45-kDa gelatin-binding and 110-kDa cell-binding fragment was measured with an MTT assay. Migration of RPE cells was measured by a Boyden chamber assay, and cell spreading was determined. Experiments were performed in the presence or absence of anti-tTG antibodies and anti-integrin alpha5 and beta1 antibodies. RESULTS: TGF-beta2 markedly induced expression of cell-surface tTG on RPE cells and increased attachment and migration on Fn and Col I. Blocking cell surface tTG inhibited attachment, migration, and spreading on Fn and its 45-kDa gelatin-binding fragment, whereas no effect was seen on Col I and the 110-kDa cell-binding Fn fragment. In contrast, blocking of integrin alpha5 and beta1 suppressed adhesion and migration on full-length Fn and the 110-kDa Fn fragment. CONCLUSIONS: These data demonstrate that TGF-beta2 increases expression of cell surface tTG, which in turn strengthens adhesion, migration, and spreading of RPE cells on Fn through the 45-kDa gelatin-binding Fn fragment. At the onset of PVR, this mechanism may help RPE cells to attach and migrate on Fn-containing matrices.

Adolescent↗
PubMed2004

Posterior vitreous detachment induced by microplasmin.

PURPOSE: To demonstrate the efficacy of microplasmin in inducing posterior vitreous detachment (PVD) and to evaluate the human and the feline retina after treatment. METHODS: Thirteen human donor eyes were injected with 62.5, 125, or 188 micro g microplasmin. The 13 fellow eyes received balanced salt solution. Four of the microplasmin-treated eyes received an additional intravitreal gas injection. After incubation at 37 degrees C for 30 minutes, all globes were placed in 4% paraformaldehyde. Retinal specimens were processed for scanning (SEM) and transmission (TEM) electron microscopy. Five feline eyes were injected with 14.5- or 25- micro g microplasmin. Animals were killed after 1 day, 3 days, or 3 weeks, and retinal specimens were evaluated by electron and confocal microscopy. RESULTS: In all control eyes, SEM demonstrated the cortical vitreous covering the inner limiting membrane (ILM). Intravitreal injection of 125 or 188 micro g microplasmin resulted in complete PVD. After treatment with 62.5 micro g microplasmin, SEM revealed collagen fibrils covering the ILM. Additional gas injection did not change the dose necessary for PVD. In vivo in cats, 25 micro g microplasmin resulted in complete PVD after 3 days. After 3 weeks, there was complete PVD with both doses of microplasmin. The retina and the ILM were well preserved in all eyes. CONCLUSIONS: Both after death and in vivo, microplasmin induces a dose-dependent cleavage between the vitreous cortex and the ILM without morphologic alterations of the retina. In the feline eye, there is no cellular response of retinal glial cells or neurons.

Adult↗
PubMed2004

Alkylphosphocholines: a new therapeutic option in glaucoma filtration surgery.

PURPOSE: To investigate the effect of alkylphosphocholines (APCs) on human Tenon fibroblast (HTF) proliferation, migration, and cell-mediated collagen gel contraction. METHODS: HTFs were isolated from tissue samples of three patients obtained during surgery and cultured in DMEM and 10% fetal calf serum (FCS). HTFs (passage 3-6) were treated with one APC in different concentrations spanning the 50% inhibitory concentration (IC(50)), as determined previously. Inhibition of cell proliferation was assessed by the tetrazolium dye reduction assay. Migration was determined in chemoattractant chambers with fibronectin-coated polycarbonated membranes. For inhibition of contraction, three-dimensional collagen gels were seeded with HTFs, and the gel size was measured. Cell viability was determined by the trypan blue exclusion assay. For analysis of the mechanism of action, protein kinase C (PKC) activity was measured. RESULTS: The IC(50) varied between 7.0 and 10.5 microM for all APCs tested. At this concentration, all four APCs inhibited HTF migration and cell-mediated collagen gel contraction in the presence of serum. The inhibitory effects on HTF proliferation, migration, and contraction were observed at nontoxic concentrations. PKC activity was reduced to 50% of control level at the IC(50) of all APCs applied. CONCLUSIONS: APCs are effective inhibitors of HTF proliferation, migration, and cell-mediated contraction of collagen gels at nontoxic concentrations. Their mechanism of action seems to involve the inhibition of the PKC pathway.

Adult↗