1/38. Fibro-osseous lesions of the external auditory canal.OBJECTIVES: To differentiate a novel type of benign circumscribed bone lesion of the external auditory canal from those described previously, such as exostoses and osteomas. STUDY DESIGN: Information was obtained from computed tomography (CT) images, surgical findings, and pathologic study. methods: Five patients (26 to 82 years old) who presented a hard, round, unilateral, skin-covered mass occluding the external auditory canal to varying degrees were studied. A CT study carried out before resection of the lesions by curettage disclosed the absence of a bony connection to the underlying structures. All the tissue specimens underwent pathologic study. RESULTS: CT and surgical findings demonstrated the absence of a connective pedicle. The pathologic findings showed lesions consisting of an osteoma-like bone formation with sparse osteoblastic areas; mature lamellar bone was observed in three cases, bone marrow containing adipose tissue and hematopoietic remnants in two, and a dense, collagenous stroma in another. They all showed irregular trabeculae, bordered by osteoid osteoblasts. In no case was there evidence of a relationship to the cartilaginous tissue or to the bony structures of the external auditory canal. CONCLUSIONS: The data obtained from the clinical, CT, surgical, and pathologic findings suggest the existence of a lesion unlike those previously known, possibly related to ossifying reactions in other parts of the organism.- - - - - - - - - - ranking = 1keywords = adipose (Clic here for more details about this article) |
2/38. Osseous metaplasia in a growth hormone-secreting pituitary adenoma.A case of growth hormone-secreting adenoma of the pituitary gland showing osseous metaplasia is described in a 56-year-old acromegalic female. The tumor was composed of nests of densely granulated cells separated by and intermixed with calcifications, trabeculae of mature bone and fat. Calcifications are seldom found in pituitary adenomas. In rare instances, calcium deposits can be prominent enough to lead to the formation of pituitary stones and bone which replace the entire tumor mass. Analogously with metaplastic meningiomas, we propose using the term metaplastic adenoma to define cases with osseous metaplasia in order to distinguish between lesions containing bone from the more frequently seen calcified adenomas.- - - - - - - - - - ranking = 0.042538456882keywords = fat (Clic here for more details about this article) |
3/38. Ossification of eustachian tube cartilage and Ostmann's fatty tissue in chronic renal failure.Ossification of the eustachian tube (ET) cartilage in 2 cases of chronic renal failure is reported for the first time. In both cases, the ossification was observed in the medial lamina of the ET cartilage. In addition, ossification of Ostmann's fatty tissue was observed in case 1, and ossification of the lateral lamina of the ET cartilage was seen in case 2. Correlation between ossification in chronic renal failure and dysfunction of the ET caused by ossified ET cartilage and Ostmann's fatty tissue is discussed.- - - - - - - - - - ranking = 0.255230741292keywords = fat (Clic here for more details about this article) |
4/38. Ossifying fasciitis.A case of ossifying fasciitis occurring in the left femoral region of a 57-year-old male is reported. The patient complained of pain in his left lower extremity which was the site of previous catheterization. During a left femoropopliteal by-pass, a firm and cylindric mass measuring 5 x 3 x 2.5 cm in size was found and extracted from the left groin. Histologically, a reactional lymph node and an irregularly shaped lesion extended into the perinodal fat tissue which is composed of proliferating fibroblasts with occasional mitotic activity. Within this fibroblastic proliferation, immature woven bone composed of osteoid with calcification and chondroid differentiation were seen. Metaplastic bone is an uncommon finding in cases of nodular fasciitis, parosteal fasciitis, cranial fasciitis and florid reactive periostitis. Ossifying fasciitis is known as an uncommon variant of nodular fasciitis. It is an uncommon post-traumatic benign lesion of subcutaneous tissue with an unclear etiology of ossification which is neither related with a bony structure nor contains any muscle tissue. This lesion has been reported only once previously, in the femoral region after a trauma history of catheterization.- - - - - - - - - - ranking = 0.042538456882keywords = fat (Clic here for more details about this article) |
5/38. Cortical dysplasia with ossification.We present the first case of cortical dysplasia with extensive intracerebral ossification. An eight-year-old epilepsy patient with a calcified lesion was successfully treated by surgical intervention. Pathological examination revealed a number of bizarre dysplastic cells in the whole lesion, which consisted of an epileptogenic cerebral cortex and a nonepileptogenic hamartomatous lesion with adipose tissue, vascular tissue, calcification, and ossification. The patient was diagnosed as having cortical dysplasia with ossification. Our findings support the notion that cortical dysplasia has a multipotentiality of cellular differentiation, including various hamartomatous tissues. We suggest that cortical dysplasia should be considered as a potential cause for epileptogenicity of a hamartomatous lesion even when magnetic resonance imaging (MRI) fails to disclose cortical dysplasia.- - - - - - - - - - ranking = 1keywords = adipose (Clic here for more details about this article) |
6/38. GNAS1 mutation and Cbfa1 misexpression in a child with severe congenital platelike osteoma cutis.We evaluated a 7-year-old girl with severe platelike osteoma cutis (POC), a variant of progressive osseous heteroplasia (POH). The child had congenital heterotopic ossification of dermis and subcutaneous fat that progressed to involve deep skeletal muscles of the face, scalp, and eyes. Although involvement of skeletal muscle is a prominent feature of POH, heterotopic ossification has not been observed in the head, face, or extraocular muscles. The cutaneous ossification in this patient was suggestive of Albright hereditary osteodystrophy (AHO); however, none of the other characteristic features of AHO were expressed. Inactivating mutations of the GNAS1 gene, which encodes the alpha-subunit of the stimulatory G protein of adenylyl cyclase, is the cause of AHO. Mutational analysis of GNAS1 using genomic dna of peripheral blood and of lesional and nonlesional tissue from our patient revealed a heterozygous 4-base pair (bp) deletion in exon 7, identical to mutations that have been found in some AHO patients. This 4-bp deletion in GNAS1 predicts a protein reading frameshift leading to 13 incorrect amino acids followed by a premature stop codon. To investigate pathways of osteogenesis by which GNAS1 may mediate its effects, we examined the expression of the obligate osteogenic transcription factor Cbfa1/RUNX2 in lesional and uninvolved dermal fibroblasts from our patient and discovered expression of bone-specific Cbfa1 messenger rna (mRNA) in both cell types. These findings document severe heterotopic ossification in the absence of AHO features caused by an inactivating GNAS1 mutation and establish the GNAS1 gene as the leading candidate gene for POH.- - - - - - - - - - ranking = 0.042538456882keywords = fat (Clic here for more details about this article) |
7/38. Intraspinal osteolipoma. Case report.Lipomatous tumors can contain uncommon or rare components (such as fibrolipoma or angiolipoma) that may result in the development of symptoms. To the best of the authors' knowledge, lipoma associated with an osseous component has not been previously reported. A case of intraspinal extradural tumor composed of both adipose and bone tissue is presented. Current theories on the cause of lipoma with an osseous component are discussed. The tumor was histologically confirmed to be an osteolipoma, and the patient recovered well after resection.- - - - - - - - - - ranking = 1keywords = adipose (Clic here for more details about this article) |
8/38. Humero-spinal dysostosis.A 2 year old boy with humero-spinal dysostosis is described. This is the third case of this disease reported in the literature. Humero-spinal dysostosis is characterised radiologically by distal humeral bifurcation, elbow subluxation and coronal cleft vertebrae. Congenital, progressive heart disease, possibly with fatal outcome, is probably part of the syndrome.- - - - - - - - - - ranking = 0.042538456882keywords = fat (Clic here for more details about this article) |
9/38. Osteolipoma of the tongue.Lipomas are common, benign tumours located in any part of the body in which fat is normally present. Some variants of lipoma have been described according to the type of tissue present. A rare variant consists of a lipoma with osseous or cartilaginous metaplasia. These lesions have been called chondrolipoma, osteolipoma, lipoma with chondroid or osseous metaplasia, lipoma with cartilaginous or osseous change, or ossifying lipoma. We present the case of an osteolipoma of the tongue in a 49-year-old female who was referred for a painless mass on the left lateral margin of the tongue, and present for about 8 years. Osteolipomas have been reported in middle-aged or elderly patients with a very long clinical history. These tumours tend to be large and to arise from the deep soft or subcutaneous tissues. The cartilage and bone is probably produced by metaplasia of fibroblasts in chondroblasts or osteoblasts. These lesions are benign and do not recur.- - - - - - - - - - ranking = 0.042538456882keywords = fat (Clic here for more details about this article) |
10/38. Microvascular changes in the lower extremities of paraplegics with heterotopic ossification.OBJECTIVES: To investigate the morphological aspects of blood microvasculature of the skin and subcutaneous tissues in subjects with paraplegia with heterotopic ossification (HO). methods: In two patients with traumatic spinal cord injury and HO, punch biopsies of skin and hypodermic soft tissue in the region of HO near the hip were studied with histological and ultrastructural methods. RESULTS: Alterations of endothelial cell and basement membrane of capillaries and small vessels were observed. Hyperactive endothelium, thickening and reduplication of the basement membrane, changes of the perivascular connective tissues and microcalcifications in the subcutaneous fat tissue were also seen. CONCLUSIONS: This present study indicates microvascular changes in the skin and subcutaneous tissue in the region of HO near the hip of two subjects with paraplegia. In our opinion the described vascular changes may induce hypoxiemic alterations of the soft para-articular tissues leading metabolic changes which may contribute to the development of HO. Therefore, it cannot be concluded whether these changes are directly responsible for HO induction.- - - - - - - - - - ranking = 0.042538456882keywords = fat (Clic here for more details about this article) |
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