PubMed Health⌕ Search

Biomedical subjects

S Dithmar

Publications and source records attributed to S Dithmar.

At least 19 recordsLinked to original sources
PubMed2007

[Subcutaneous leiomyosarcoma metastatic to the eyelid].

BACKGROUND: Metastatic eyelid lesions are rare. Most metastatic lesions to the eyelid are carcinomas. Leiomyosarcomas are soft tissue sarcomas arising most commonly in the uterus and gastrointestinal tract, whereas dermal leiomyosarcomas are less frequent. Dermal leiomyosarcomas metastatic to the eyelid have not been reported so far. CASE REPORT: A 28-year-old female patient presented with a rapidly growing tumor of her right lower eyelid. A subcutaneous leiomyosarcoma of the neck had been excised 21 months before with subsequent radiotherapy. Seven months later metastases to the lung, liver, and left upper arm were detected. The patient received chemotherapy. The eyelid tumor was completely excised. Histologically the lesion consisted of spindle cells arranged in fascicles with perinuclear vacuoles and myofilaments. There was a strong immunoreactivity for smooth muscle actin, and negative staining for cytokeratin and S100. CONCLUSION: Cutaneous and subcutaneous leiomyosarcomas occur at almost any age, but are most common between the 5th and 7th decades. They are more common in men and usually occur at the extremities. The prognosis of cutaneous/subcutaneous leiomyosarcoma correlates with the depth of the tumor. To our knowledge this is the first presentation of a subcutaneous leiomyosarcoma metastatic to the eyelid. Presumably, parenchymatous metastases of this tumor occur before dermal metastases arise.

Adult↗
PubMed2006

[Solitary iris metastasis from breast cancer. Effective local therapy with electron beam irradiation].

BACKGROUND: The prevalence of intraocular metastases from breast cancer is approximately 4-5%. Solitary metastases of the iris are rare. We report on successful treatment of a solitary iris metastasis using electron beam irradiation. CASE REPORT: A 30-year-old patient presented with an amelanotic tumor of the iris and the anterior chamber angle of her right amblyopic eye. The patient had undergone left-sided breast-conserving surgery and lymph node dissection 3 years before followed by chemotherapy and radiotherapy. The iris tumor was considered a metastasis. Fractionated electron beam irradiation was performed applying a total dose of 50 Gy in fractions of 5 x 2 Gy/week, electrons (9 MeV). The iris metastasis was completely resolved 13 months after radiotherapy. Until now no signs of cataract have been detected and visual acuity has remained stable. CONCLUSION: Electron beam irradiation of this iris metastasis was an effective treatment for preserving visual acuity and ocular function with tolerable acute toxicity and so far no adverse side effects.

Adult↗
PubMed2006

[Neurodermatitis. A risk factor for the development of squamous cell carcinoma].

Squamous cell conjunctival carcinomas (SCCC) are rare. We report on a 34-year-old patient with neurodermatitis and chronic conjunctivitis who presented with a therapy-resistant corneal ulcer induced by mechanical irritation diagnosed as SCCC. Chronic blepharoconjunctivitis seems to sustain the development of SCCC in patients with neurodermatitis because of their insufficient immune response.

Adult↗
PubMed2006

[Radial optic neurotomy for central retinal vein occlusion -- how deep should it be?].

PURPOSE: Most of the studies on radial optic neurotomy (RON) have not defined the depth of the incision. Complications following a deeper incision have been described. This histological study was performed to evaluate the required depth for RON. METHODS: Serial sections of the area of the optic nerve head were performed in 19 eye bank eyes. The distance between the inner surface of the optic disc and the outer limit of the cribriform plate was measured. Ten additional eye bank eyes underwent 2 mm deep experimental RON using the Spaide CRVO Knife (DORC, Netherlands). The cutting depth was assessed histologically by serial cuts. RESULTS: The distance between the inner surface of the disc and the outer limit of the cribriform plate measured 1.35+/-0.3 mm (shrinkage-revised value: 1.45 mm). The experimental RON showed cutting depths of 1.53+/-0.3 mm (shrinkage-revised value: 1.65 mm). CONCLUSION: Based on normal eyes, a cutting depth of 1.45 mm is sufficient to cut through the cribriform plate. This might change during central retinal vein occlusion because possible papillary edema due to central retinal vein occlusion has to be considered. Even under controlled experimental conditions RON leads to great variation in incision depths. The development of a knife with a fixed penetration depth would be helpful.

Ethmoid Bone↗
PubMed2006

[Current strategies for macular hole surgery in Germany, Austria and Switzerland].

BACKGROUND: Main aim of this study was to determine how macular hole surgery is currently being performed in Germany, Austria and Switzerland. METHODS: A questionnaire concerning the different aspects of surgery for stage 3 macular hole was developed and sent out to the 380 members of the German Retina Society. RESULTS: This analysis is based on 129 returned questionnaires from colleagues who perform macular hole surgery. A total of 95% (n=123) of the surgeons routinely perform vitrectomy with posterior vitreous detachment, peeling of epiretinal tissue and internal limiting membrane (ILM) peeling. Some 86% (n=106) stain the ILM, with 80% of these (n=85) using indocyanine green (ICG) in concentrations ranging from 0.005% up to 10%. Fourteen percent of ICG users perform a fluid-air exchange before applying the dye. Platelet concentrate is used by 8% of the surgeons with 97% (n=125) performing a gas tamponade using SF6 (53%), C3F8 (22%), C2F6 (16%) or just air (5%) (multiple answers: 4%). Simultaneous cataract surgery is routinely performed by 8%; by 73% only if there is significant cataract. CONCLUSIONS: There is common consent on the basic surgical steps, but several surgical details, e.g. ILM staining, are performed in substantially different ways.

Austria↗
PubMed2006

[Functional results after anatomically successful surgery for stage III/IV macular hole].

PURPOSE: To report the functional results after anatomically successful surgery for stage III/IV macular hole. METHODS: Follow-up examinations (ETDRS charts, Birkhäuser near visual acuity charts, OCT) were carried out in 29 patients 11+/-5 months after surgery for stage III/IV macular hole (hole size >400 microm); in all cases the foveal contour had been restored postoperatively . The surgery performed also included cataract surgery (n=26), vitrectomy, ICG-assisted ILM peeling (in which perfluorcarbon liquid was used to prevent ICG from coming in contact with the retinal pigment epithelium) and tamponade with intraocular gas (n=16) or silicone oil (n=13). Silicone oil had been removed by the time of the follow-up evaluation. RESULTS: Preoperative mean BCVA was 0.2 (0.64 logMAR+/-0.24) and postoperative BCVA, 0.5 (0.3 logMAR+/-0.19). None of the patients experienced any deterioration in sight; the average improvement in visual acuity was 3.5+/-2 lines. In 70% (n=20) of the patients the postoperative BCVA was > or =0.5. Visual acuity for near sight was 0.45+/-0.2. In 66% (n=19) a visual acuity of > or =0.4 was achieved for close work. The improvement in visual acuity was not related to the kind of endotamponade or to the size of the macular hole. Patients with macular hole diameters of 400-800 microm (n=20) gained 3.5+/-2.,4 lines, while in patients with macular hole diameters of 800-1135 microm the average gain was 3.6+/-1.3 lines. CONCLUSIONS: Anatomically successful macular hole stage III/IV surgery with ICG-assisted ILM peeling and protection of the retinal pigment epithelium from contact with ICG by perfluorcarbon liquid can yield good functional results.

Aged↗
PubMed2005

[Macular hole. Survey and relevant surgical concepts].

The theory of macular hole pathogenesis, which had so far been based on biomicroscopy, has been considerably altered by optical coherence tomography. The precise presentation of vitreofoveal pathology shows that forces acting in different directions are associated with different stages of the disease, making surgical treatment adapted to the different stages possible. Some surgical procedures are still controversial, and there is still no gold standard in macular hole surgery. Especially no agreement exists on the benefit of internal limiting membrane peeling, possibly assisted by staining with indocyanine green. Also details of endotamponade and postoperative positioning are controversial. Therefore, the method of surgical treatment depends a lot on the individual surgeon. This review summarizes the broad spectrum of the literature and the present knowledge in this field.

Animals↗
PubMed2005

Classification of abnormal fundus autofluorescence patterns in the junctional zone of geographic atrophy in patients with age related macular degeneration.

AIM: To describe and classify patterns of abnormal fundus autofluorescence (FAF) in the junctional zone of geographic atrophy (GA) in patients with age related macular degeneration. METHODS: Digital FAF images were recorded in 164 eyes of 107 patients using a confocal scanning laser ophthalmoscope (cSLO; excitation 488 nm, detection above 500 nm) as part of a prospective multicentre natural history study (FAM Study). FAF images were obtained in accordance with a standardised protocol for digital image acquisition and generation of mean images after automated alignment. RESULTS: Image quality was sufficient for classification of FAF patterns in 149 eyes (90.9%) with lens opacities being the most common reason for insufficient image quality. Abnormal FAF outside GA in 149 eyes was classified into four patterns: focal (12.1%), banded (12.8%), patchy (2.0%), and diffuse (57.0%), whereby 12.1% had normal background FAF in the junctional zone. In 4% there was no predominant pattern. The diffuse pattern was subdivided into four groups including reticular (4.7%), branching (27.5%), fine granular (18.1%), and fine granular with peripheral punctate spots (6.7%). CONCLUSIONS: Different phenotypic patterns of abnormal FAF in the junctional zone of GA can be identified with cSLO FAF imaging. These distinct patterns may reflect heterogeneity at a cellular and molecular level in contrast with a non-specific ageing process. A refined phenotypic classification may be helpful to identify prognostic determinants for the spread of atrophy and visual loss, for identification of genetic risk factors as well as for the design of future interventional trials.

Aged↗
PubMed2003

[Atypical tonic pupil as a complication of chickenpox infection].

BACKGROUND: Pupillary disorders following varicella infections are rare and few cases have been reported which were only partially pharmacologically tested. MATERIALS AND METHODS: A 5-year-old boy presented with a left-sided dilated and unreactive pupil, 3 months before he had suffered from chickenpox and in the course of the acute disease developed anterior uveitis which was treated with local prednisone and mydriatics. The pupil remained dilated despite discontinued medication, light reaction was absent and accommodation was impaired. Pilocarpine supersensitivity was an indication against a lesion of the sphincter muscle and reduced response to cholinesterase inhibitors (physostigmine) pointed towards a postganglionic lesion. CONCLUSIONS: It is probable that a varicella virus infection of the short ciliary nerves and the ciliary ganglion caused anterior uveitis and a postganglionic parasympathetic nerve lesion, clinically presenting as a tonic pupil. According to cases previously reported an irreversible nerve lesion has to be assumed.

Anti-Inflammatory Agents↗
PubMed2003

[Progressive peripunctal nevus in an adult].

Nevi arise from migration of melanocytes into the epithelium. Over the years they experience a typical maturation, with the possibility of an increased thickness due to accompanying inflammation or fibrosis but actual growth of nevi is rare in adults. A 70-year-old patient presented with a growing tumour around the punctum lacrimale. The histological examination revealed a conjunctival nevus without any transformation. Peripunctal nevi are rare. The localisation of a nevus in the area of the punctum lacrimale was first published in 1931 and only 10 other patients with such a nevus have been reported. If at all, an enlargement of a peripunctal nevus has been described in younger patients. The patient presented here showed significant growth of the nevus at an atypically high age without any histological signs of malignancy or proliferation. The reason for this uncommon nevus enlargement remains unclear.

Aged↗
PubMed2003

[Retinal vein occlusions].

There are still gaps in understanding the etiology and pathogenesis of circulatory disorders of the central retinal vein. Although various new therapeutic approaches have been developed in the past few years, existing therapy forms are subject to controversy and available data are to some extent inconsistent. This discussion in the German-language literature is associated with varied and nonuniform terminology, which should do justice in particular to concepts of pathomechanism and degree of specificity. The general designation, "occlusion" seems to be the most suitable of all available terms since this implies no conclusions on possible etiological factors. Retinal vein occlusions develop at different sites and to varying extents. Depending on t he location of the occlusion, they can be classified into occlusions of the central vein, hemicentral vein, major branch vein, and macular branch vein. This overview provides information on the current knowledge of the pathogenesis and both established approaches and those in ongoing clinical trials for the treatment of central venous and branch vein occlusions.

Diagnosis, Differential↗
PubMed2003

[Prophylactic pan-coagulation from ischemic central vein occlusions? Practicability of the results from the Central Vein Occlusion Study Group].

PURPOSE: Central vein occlusions (CVO) with an avascular area of more than 10 optic-disc areas are classified as ischemic by the Central Vein Occlusion Study Group (CVOSG). For patients without neovascularizations (NV) clinical controls every 4 weeks during the first 6 months are recommended instead of prophylactic pancoagulation (PC). In this study we examined the practicability of this recommendation. PATIENTS AND METHODS: We analysed the records of 15 patients with ischemic CVO and no clinical signs of NV and no prophylactic PC retrospectively. All these patients developed a neovascular glaucoma (NVG) despite using the criteria of the CVOSG and were then treated with cyclophotocoagulation (CPC). RESULTS: The time between first presentation and CPC was 4.4+/-2.9 months. Of these patients 7 developed a NVG within 4 weeks after initial presentation. CONCLUSIONS: This study shows that NV and NVG may develop much faster than 4 weeks and can already be irreversible. Therefore it seems advisable to follow-up patients with increased risk factors even more frequently especially during the initial phase after CVO.

Aged↗
PubMed2002

[HLA class I antigen expression correlates with histological cell type in uveal melanoma].

PURPOSE: The prognosis of uveal melanoma is correlated with its histologic cell type. The epithelioid cell type is associated with a higher metastatic rate than the spindle cell type. The Human Leucocyte Antigen Class I (HLA-I) expression of the melanoma also correlates with the prognosis. In this study, we analyzed HLA-I antigen expression of uveal melanomas to determine whether a relationship exist between antigenic expression and melanoma cell type. METHODS: Formalin-fixed, paraffin-embedded spindle cell type (n = 11) and epithelioid cell type (n = 11) uveal melanomas were immunostained with the HC10 antibody (1:80) for HLA-I antigen expression with appropriate positive and negative controls. Sections were assessed semiquantitatively according to the percentage of stained cells. RESULTS: Among the spindle cell type melanomas, 2 out of 11 (18%) stained with HC10 antibodies. The staining intensity was less than 25% of the cells in these two melanomas. Among the epithelioid cell type melanomas, 9 out of 11 (82%) stained with HC10. The staining intensity was more than 25% of the cells in 5 of these 9 melanomas. CONCLUSIONS: It is unknown why spindle and epithelioid cell type uveal melanomas have different prognoses. Human uveal melanoma cell lines with low HLA-I expression are susceptible to NK cell-mediated lysis in vitro and in murine studies. The prognostically more favorable spindle cell type melanoma expresses less HLA-I than the epithelioid cell type melanoma. These results stress the role of NK cells in the rejection of uveal melanoma.

Histocompatibility Antigens Class I↗
PubMed2001

Murine high-fat diet and laser photochemical model of basal deposits in Bruch membrane.

OBJECTIVE: To examine the histologic, histochemical, and ultrastructural changes in Bruch membrane in mice on a high-fat diet with and without laser photochemical injury. METHODS: Five groups of C57BL/6 mice were studied. Group 1 included 2-month-old mice on a normal diet; group 2 included 8-month-old mice on a normal diet; group 3 included 8-month-old mice on a high-fat diet; groups 4 and 5 included 8-month-old mice on a normal diet or high-fat diet, respectively, that underwent laser application of one eye with argon blue laser (488 nm). The mice were killed and plasma lipid levels were measured. The eyes were examined by standard electron microscopy, filipin histochemistry for unesterified cholesterol (UC) and esterified cholesterol (EC), and the osmium-tannic acid-phenylenediamine method for preserving extracellular lipid particles. RESULTS: The plasma cholesterol level was significantly higher in the mice on the high-fat diet than the controls (P<.001). Bruch membrane was thicker in group 2 than group 1 (P =.04) and group 3 had a thicker Bruch membrane than group 2 (P =.003). All eyes in group 3 exhibited accumulation of electron-lucent debris. There was no histochemical and ultrastructural evidence that this material represented accumulated UC or EC. Seven of 9 laser-injured eyes in group 5 accumulated basal laminar deposit (BlamD)-like material in Bruch membrane (P =.02). CONCLUSIONS: Electron-lucent debris accumulates in murine Bruch membrane, and the amount correlates with age and high-fat diet. This debris has some similarities with basal linear deposits, although the debris does not form a discrete layer external to the basement membrane of the retinal pigment epithelium as occurs in basal linear deposits. These deposits do not appear to be UC or EC. Laser photochemical injury of the retinal pigment epithelium may result in the appearance of BlamD-like deposits in eyes with electron-lucent debris. The BlamD-like deposits in this model are similar to the basal laminar deposits that occur in age-related macular degeneration. CLINICAL RELEVANCE: This is an animal model of ultrastructural BlamD-like material in Bruch membrane that is very similar to the deposits that occur in age-related macular degeneration.

Animals↗
PubMed2001

[Metastatic uveal melanoma. Development of neoadjuvant treatment in animal experiments].

BACKGROUND: Up to 50% of patients with uveal melanoma develop metastases but none of the existing treatments of the primary tumor has been able to reduce the metastatic rate. Probably, micrometatases have already developed before treatment of the uveal melanoma and dormant micrometastases can persist for years before they start growing. This long time-span provides the possibility to treat micrometastases. METHODS: In order to develop an animal model for metastatic uveal melanoma, B16 melanoma cells were injected into the posterior ocular compartment of C57BL6 mice. These cells grew and metastasised to the lungs and liver. Immunological factors for the metastatic process and possible neoadjuvant treatments were investigated. RESULTS: Natural killer cells (NK) are of significance in the rejection of metastases and HLA-I expression of uveal melanomas correlates with the melanoma cell type. Interferon-alpha-2b increases the activity of NK cells and reduces the metastatic rate in the animal model. CONCLUSION: Treatment with interferon-alpha-2b results in decreased metastases from intraocular melanoma in a murine model.

Animals↗
PubMed2001

Interleukin-18 expression and modulation in human corneal epithelial cells.

PURPOSE: The interferon-gamma-inducing factor Interleukin-18 (IL-18) is a recently described cytokine that appears to have multiple important pro-inflammatory effects including the induction of interferon-gamma (IFN-gamma) by activated T-cells. The expression of IL-18 by human cornea has not been previously reported. In the present study, we examine the possibility that human corneal epithelial cells are capable of producing this leukocyte-activating factor which may play an important role in IFN-gamma-dependent inflammation responses in the cornea. METHODS: Northern blot analysis and ELISA were used to investigate the in vitro expression of IL-18 mRNA and protein respectively in primary (HCEC) and transformed human corneal epithelial cells (HCET). To determine if IL-18 expression was modulated by pro-inflammatory mediators, cells were treated with lipopolysaccharide (LPS), phorbol 12-myristate 13-acetate (PMA) or synthetic double stranded RNA (poly dI : dC). IL-18 bioactivity was determined in a leukocyte interferon-gamma induction assay and IL-18 was immunolocalized in whole human cornea by immunohistochemistry using a specific anti-IL-18 antibody. RESULTS: IL-18 mRNA and bioactive protein was constitutively expressed by human corneal epithelial cells and upregulated by PMA, LPS and poly dI : dC. The constitutive expression of IL-18 protein immunoreactivity was also demonstrated in the epithelial cells of whole human cornea tissue. CONCLUSIONS: This is the first study demonstrating that corneal epithelial cells are capable of producing the IFN-gamma inducing factor IL-18. Increased bioactive corneal IL-18 production can be induced by a number of pro-inflammatory agents and may play an important role in initiating gamma-interferon-mediated inflammatory responses in the cornea.

Blotting, Northern↗