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Steffen Heegaard

Publications and source records attributed to Steffen Heegaard.

35 records · Page 2Linked to original sources
PubMed2004

Recent advances in early-onset severe retinal degeneration: more than just basic research.

Successful treatment of early-onset sever retinal degeneration (EOSRD) in an animal model of the disease has provided the first proof-o-principle for retinal gene therapy of higher mammals. Currently, large sets of DNA samples are screened to identify patients with Leber's congenital amaurosis (LCA) carrying mutations in RPE65 as possible candidates for gene therapy trials. Research into EOSRD and LCA aims to identify the function of proteins involved or phenotypic changes upon mutation. These data will be used to describe the disease phenotype and identify parameters that can predict the outcome of gene therapy trials.

Acyltransferases↗
PubMed2004

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↗
PubMed2004

Melanopsin is expressed in PACAP-containing retinal ganglion cells of the human retinohypothalamic tract.

PURPOSE: The putative circadian photoreceptor melanopsin is found in rodents in a subpopulation of intrinsic light-sensitive retinal ganglion cells (RGCs) constituting the retinohypothalamic tract (RHT). The study was conducted to determine whether melanopsin is expressed in the human retina and costored with the neuropeptide pituitary adenylate cyclase activating polypeptide (PACAP), a marker for the RHT, projecting to the suprachiasmatic nucleus (SCN). Furthermore, whether melanopsin expression is conserved in retinas of blind patients with severe retinal degeneration was investigated. METHODS: In situ hybridization and immunohistochemistry was used to demonstrate melanopsin synthesis in human eyes of 17 donors and two postmortem hypothalami containing the SCN. The coexistence of melanopsin and PACAP in elements of the retinohypothalamic tract was studied by dual-labeling immunocytochemistry. RESULTS: Melanopsin expression was found in a subpopulation of RGCs located in the ganglion cell layer and displaced in the inner nuclear cell layer. Melanopsin-containing cells comprised approximately 0. 8% of all RGCs, with a distinct morphology characterized by two to four dendritic processes constituting a panretinal network. Melanopsin immunoreactivity was primary present at perikaryal boundaries and neuronal processes and to some extent also in the cytoplasm. PACAP and melanopsin were colocalized in the RGCs and PACAP-containing nerve fibers, seemingly innervating the retinorecipient part of the SCN. Melanopsin-expressing RGCs were conserved in retinas of blind patients with severe degeneration of the outer and/or inner layers. CONCLUSIONS: Given the expression of melanopsin in PACAP-containing RGCs of the human RHT, this photoreceptor is a likely first base in the chain of events leading to photoentrainment of both normal and blind people.

Aged↗
PubMed2003

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↗
PubMed2003

Neuroepithelial tumor of the retina in a dog.

ANIMAL STUDIED: At routine vaccination a tumor in the right eye of a Golden Retriever was diagnosed. PROCEDURE: The eye was enucleated, fixed in formalin and processed according to routine paraffin technique. Standard histologic, histochemical and immunohistochemical stainings were applied. Formalin-fixed tissue was used for electron microscopic examination. RESULTS: The tumor originated from the retina and was composed of two different morphologic parts, a retinoblastoma-like part of small neuroepithelial cells and a medulloepithelioma-like part of columnar cells arranged in cords. DISCUSSION AND CONCLUSION: It is discussed whether the tumor had its origin in different clones or in one clone, and it is suggested that the double differentiation might be the result of a transformation of retinal cells, demasking stem cell-like potentials.

Animals↗
PubMed2003

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↗
PubMed2002

[Zone therapy and asthma].

INTRODUCTION: Many patients with asthma seek alternative or adjunctive therapies. One such modality is reflexology. Our aim was to examine the popular claim that reflexology treatment benefits bronchial asthma. MATERIAL AND METHODS: Ten weeks of either active or simulated (placebo) reflexology were compared in an otherwise blind, controlled trial of 40 patients with asthma. RESULTS: Objective lung function tests did not change. Subjective scores and bronchial sensitivity to histamine improved on both regimens, but no differences were found in the groups receiving active or placebo reflexology. However, a trend in favour of reflexology became significant when a supplementary analysis of symptom diaries was carried out. At the same time a significant pattern compatible with subconscious un-blinding was found. DISCUSSION: We found no evidence that reflexology has a specific effect on asthma beyond a placebo influence.

Adolescent↗
PubMed2002

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↗
PubMed2002

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↗
PubMed2002

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↗
PubMed2002

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↗
PubMed2002

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↗
PubMedDate not supplied

Malignant teratoid medulloepithelioma with brain and kidney involvement in a dog.

ANIMAL STUDIED: A tumor of the left eye with involvement of the brain and kidney was diagnosed in a 4-year-old Neapolitan mastiff. PROCEDURE: The dog presented with acute glaucoma of the left eye. Peripheral corneal vascularization and severe corneal edema obscured examination of deeper structures. Because of concurrent progressive neurologic signs the dog was euthanized and a postmortem examination was performed. The eyes, brain and samples from the lung, heart, liver and kidneys were fixed in 4% neutral buffered formalin and embedded in paraffin wax. Sections were examined by light microscopy including histochemical and immunohistochemical staining. RESULTS: The ocular tumor originated from the ciliary body and was composed of small islets and cords of poorly differentiated, oval to polyhedral cells surrounded by abundant ground substance. Areas with chondroid differentiation were observed. Rosettes were not found. Metastases with the same morphology were present in the brain and in one kidney. CONCLUSION: An intraocular malignant teratoid medulloepithelioma with metastases to the brain and kidney is presented.

Animals↗