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Jan Ulrik Prause

Publications and source records attributed to Jan Ulrik Prause.

34 records · Page 2Linked to original sources

Primary corneal myxoma.

PURPOSE: To present the clinical and histopathological characteristics of a corneal myxoma. METHODS: A 36-year-old, white woman presented with blurred vision and a whitish opacity on the left cornea. Clinical examination revealed a whitish, non-tender, 5 x 9 mm superficial tumour on the cornea. The tumour was excised and examined microscopically. RESULTS: The tumour was composed of spindle-shaped cells in a myxomatous ground substance. Immunohistochemically, the tumour cells were positive for vimentin, muscle-specific antigen and smooth muscle antigen. The tumour was classified as a myxoma of the cornea. The origin of the tumour is discussed. CONCLUSION: This is the second reported case of a corneal myxoma without prior corneal disease.

Adult↗

Metastases in the ophthalmic region in Denmark 1969-98. A histopathological study.

PURPOSE: To evaluate the patterns of origin and anatomical localization of histologically verified metastases in the ophthalmic region in Denmark during 1969-98, and to compare the findings with those of a similar study for the period 1944-68. METHODS: All metastatic lesions presented at the Eye Pathology Institute, University of Copenhagen during the period 1968-98 were investigated. RESULTS: Metastases were found in 81 specimens from the eye and eye region in 76 patients (32 men, 44 women). Five patients had bilateral involvement. The most frequent site of involvement was the uvea (63%), followed by the orbit (26%) and the eyelids (10%). Breast cancer accounted for the most frequent primary tumour (38%), followed by lung cancer (24%) and skin melanoma (14%). CONCLUSION: The pattern of anatomical location of metastases in the ocular region has not changed since 1944. The incidence of metastases has fallen significantly throughout the period.

Adolescent↗

Melanoma-associated spongiform scleropathy: biochemical changes and possible relation to tumour extension.

PURPOSE: To investigate biochemical changes of the sclera in eyes with melanoma-associated spongiform scleropathy (MASS), and to analyse possible relationships between these changes and tumour extension. METHODS: Sections from 364 eyes, enucleated for choroidal and ciliary body melanoma, were examined for MASS and scleral tumour extension. Biochemical analysis was also performed on eight scleral specimens with MASS and eight specimens (controls) from morphologically normal sclera of the same eyes. The scleral thickness of each specimen was measured. Samples were delipidized, dried and weighed. The weight ratios of collagen-related amino acids were calculated based on quantitation by liquid chromatography. Amounts of glycosaminoglycans (GAGs) were determined by electrophoresis. RESULTS: Melanoma-associated spongiform scleropathy was seen in 140 eyes (38.5%). Tumour scleral extension was observed in 82 eyes. Of these 82 eyes, 75 (91.5%) had MASS (p<0.05). Biochemically, the majority of the main amino acids of the scleral collagen and total proteins were significantly lower in areas with MASS than in the control specimens. Specific GAGs and total GAGs were found in significantly higher concentrations in areas with MASS than in the control specimens. Scleral thickness was also significantly higher in areas with MASS than in the control specimens. CONCLUSIONS: The reduced content of collagen manifested by decreased amino acids and total proteins indicates collagen degradation in the vicinity of the tumour. The concomitant excessive deposition of GAGs accumulates water and may cause loosening of the already degraded collagen bundles, giving a histopathological picture of MASS. These changes could facilitate tumour cell migration and may explain the high incidence of MASS in eyes with scleral tumour extension.

Chromatography, High Pressure Liquid↗

Nordic research in ophthalmology.

PURPOSE: To provide an overview of some of the current activities in eye research in the Nordic countries. METHODS: The presentations at the biannual Nordic Congress of Ophthalmology, held in Tampere, Finland in 2002, were reviewed and the contributions found most noteworthy are included in this article along with a limited discussion of each research field. However, space requirements prevented the inclusion of many interesting scientific contributions. RESULTS: Important contributions in various subfields of eye research and ophthalmology are reviewed. These include cornea, cataract, paediatric ophthalmology, glaucoma, diabetic eye disease, age-related macular degeneration, physiology and pharmacology and oncology. CONCLUSIONS: Eye research is very active in the Nordic countries and significant contributions are being made to ophthalmology in several fields on a world scale. We hope to continue to review Nordic contributions to eye research after each Nordic Congress of Ophthalmology and plan to make the reviews more systematic and comprehensive in the future.

Biomedical Research↗

Histopathologically verified non-vascular optic nerve lesions in Denmark 1940-99.

PURPOSE: To evaluate the distribution in Denmark of histologically verified optic nerve lesions according to histological diagnosis, gender and age during a period of 60 years and to calculate frequency and possible changes in frequency during the observation period. METHODS: All optic nerve lesions reported at the Eye Pathology Institute, University of Copenhagen, during the period 1940-99 were investigated. All similar lesions reported at all pathological departments in Denmark during 1974-99 were also investigated. RESULTS: The number of optic nerve lesions identified totalled 313 in 298 patients. The frequency of histopathological optic nerve lesions was seen to have increased significantly over the last 25 years, and at present, an average of 12 lesions per year are recorded. Lesions in children represented 42% (130). The percentage of lesions suffered by children remained constant throughout the observation period. Benign tumours constituted 33% (44) of the total number of tumours in adults and 61% (62) in children. Frequencies of glioma and optic nerve sheath meningioma increased significantly during the last 25 years. Subjects presenting with optic nerve sheath meningioma exhibited a significant difference in age at presentation: the mean age of women at presentation was seen to be 48.8 years, while the mean age of men at presentation was seen to be 29.7 years. The most frequent lesion seen in children was glioma and in adults invasion from malignant uveal melanoma. CONCLUSION: Histologically diagnosed optic nerve lesions are rare and consist primarily of tumours. The increase in frequency of optic nerve lesions in Denmark during the last 25 years is due to an increase in the number of benign tumours.

Adolescent↗

Transplantation of allogenic anterior lens capsule to the subretinal space in pigs.

PURPOSE: To investigate the consequences of transplantation of a new basement membrane to the subretinal space (SRS) as a substitution of Bruch's membrane. METHODS: Porcine anterior lens capsules (ALC) were transplanted to the subretinal space of 20 eyes from 19 young Danish landrace pigs. All pigs underwent a three port localized pars plana vitrectomy. Seventeen eyes received naked ALC. In three experiments the ALC was embedded in gelatine, in order to prevent curling of the ALC. The observation period varied between zero and 49 days. The pigs were examined by ophthalmoscopy and fundus photography. Histopathological examination of enucleated eyes was performed at the end of the experiment. RESULTS: ALCs transplanted to the subretinal space were well-tolerated and caused no inflammation when Bruch's membrane was left undamaged. After 11 days host RPE and glial cells started to cover the ALC in a competitive fashion. When Bruch's membrane was damaged, ingrowths of choroidal vessels and fibroblasts was prominent. The use of gelatine to flatten the ALC did not prevent curling, and gelatine caused pronounced inflammation. CONCLUSIONS: It is possible to transplant porcine ALC to the SRS of the pig. ALCs are well-tolerated in the SRS and are covered with well-differentiated monolayers of host RPE-cells, if Bruch's membrane is left intact.

Animals↗

Characterization of melanoma associated spongiform scleropathy.

PURPOSE: Melanoma associated spongiform scleropathy (MASS) describes areas within the sclera where collagen bundles appear to have disintegrated into loose fibres. It is found adjacent to choroidal and ciliary body melanoma. This study aimed to characterize these changes histopathologically. METHODS: Sections of 218 eyes that had been enucleated for malignant melanoma between January 1994 and June 2000 were examined for MASS, using data collected from the files of the Eye Pathology Institute, University of Copenhagen. Findings were correlated to patient characteristics (age, gender and pre-enucleation radiation) and tumour characteristics (location, morphology and invasion). Staining was applied using haematoxylin-eosin (HE), periodic acid-Schiff (PAS), haematoxylin-phloxine-saffron (HPS), alcian blue, colloidal iron and Masson's trichrome. Sixteen normal eyes and 29 eyes with diseases other than choroidal and ciliary body melanoma served as controls. RESULTS: Melanoma associated spongiform scleropathy was observed in 73 of the 218 eyes (33%) with melanoma. No changes were found in normal eyes or in eyes with other intraocular diseases. A significantly higher incidence of MASS was found in older age groups. Thirty-six (49%) of the 73 cases of MASS were observed within a patient age range of 71-90 years, whereas only 14 cases (19%) were observed within an age range of 41-60 years. Pre-enucleation radiation significantly reduced the incidence of MASS. Twenty-two (10%) of the total 218 eyes had received pre-enucleation radiation and in only two (1%) of these was MASS observed. Melanoma associated spongiform scleropathy was found only in areas of contact between the tumour and the sclera, and the degree of MASS correlated directly with the extent of this contact. No significant correlation with tumour cell type was found. CONCLUSIONS: In eyes with MASS, the severity of the changes correlated to the extent of direct contact between the tumour and sclera. Melanoma associated spongiform scleropathy showed a significant predilection towards older age groups. Pre-enucleation radiation significantly reduced the incidence of MASS. Melanoma associated spongiform scleropathy is probably caused by a deposition of amorphous material splitting the scleral collagen fibrils. This material may be secreted either directly from the adjacent tumour or from scleral fibroblasts stimulated by the tumour cells.

Adolescent↗

Orbital intramuscular haemangioma.

PURPOSE: To present the clinical and histopathological characteristics of an intramuscular haemangioma in the extraocular muscles. METHODS: In 1989, an otherwise healthy 21-year-old female developed proptosis of the left eye. Clinical examination revealed a painless, non-compressible, retrobulbar lesion. No discoloration of skin or conjunctiva could be observed. The patient had no history of head injury. She underwent surgery three times over a period of 9 years, without reaching a diagnosis. The tumour increased slowly in size despite the operations and MR imaging suggested a tumour of angiomatous origin. Finally, radical surgery was performed with enucleation of the left eye and excision of affected extraocular muscles. RESULTS: Histopathological examination of the removed orbital tumour showed a mixed type intramuscular haemangioma involving four extraocular muscles. CONCLUSION: We report the first case of an intramuscular haemangioma of the orbit.

Adult↗

Castleman's disease in the orbit. A 20-year follow-up.

PURPOSE: To report a case of localized orbital Castleman's disease of mixed cell type with a follow-up of 20 years. METHODS: A female patient presented at the age of 12 years with constitutional symptoms and left-sided proptosis. Laboratory tests revealed marked hypergammaglobulinaemia and high erythrocyte sedimentation rate (ESR), suggesting an immunological disturbance. A CT scan and MRI showed an infiltrating orbital mass lateral to and behind the eye. RESULTS: Histological examination of orbital biopsies showed a lymphoid lesion consistent with Castleman's disease of the mixed cell type. The patient was treated with systemic steroids, immunosuppressives and irradiation. She is now 33 years old and has been without relapse for the last 7 years. CONCLUSION: Orbital involvement in Castleman's disease is very rare. The clinical course, good prognosis and histological picture of the present case favour the diagnosis of localized Castleman's disease of mixed cell type. The successful medical treatment suggests that such a regime may substitute for surgery when the latter proves difficult.

Adult↗

Primary palpebral and orbital ossification in pseudo-pseudohypoparathyroidism.

PURPOSE: To present a case of ossification of the eyelid, episclera and orbit in a patient with pseudo-pseudohypoparathyroidism (pPHP). METHODS: A 20-year-old woman diagnosed with pseudo-pseudohypoparathyroidism underwent clinical and histopathological examination of calcified plaques of the right eyelid and orbit. The patient presented with a round face, tousled short hair and retarded speech. She had been diagnosed with pPHP at 3 years of age. During her first decade, calcified plaques developed in the right eyelid and orbit. Gradually, she developed horizontal diplopia, pseudo-ptosis and periorbital pain. Vertical eye movements were reduced to 10 mm, although levator function remained intact. Computer tomography scans of the orbit showed three separate dense structures. Radiographic findings also showed bilateral shortening of the fourth metacarpus and a calcified subcutaneous plaque in the left thigh. The patient's blood status revealed an elevated level of thyroid stimulating hormone, but was otherwise normal. The patient was treated with eltroxin and shortly afterwards regained normal hair and normal speech function. RESULTS: The calcified structures were removed surgically and almost normal eye movements were re-established. Histological examination of the excised tissue demonstrated bone formation. CONCLUSION: This is the first reported case of ossification of the eyelid and orbit in a patient with pseudo-pseudohypoparathyroidism.

Adult↗