Remide Arkun

Liposarcoma of soft tissue: MRI findings with pathologic correlation

ObjectiveTo evaluate the MRI findings of liposarcomas of different histologic types and correlate these with the histopathologic features.DesignThe MR images of seven liposarcomas were reviewed retrospectively to assess the tumor size, location, margination, signal characteristics and enhancement patterns in different histologic types.PatientsSeven liposarcomas comprising three well-differentiated, two myxoid and two pleomorphic types were evaluated.Results and conclusionAll tumors showed well-defined and mostly lobulated margins. The well-differentiated liposarcomas were composed mainly of fat with septations or nodules, were hyperintense on T2-weighted images, and demonstrated faint enhancement or no enhancement following intravenous contrast. Myxoid liposarcomas were homogeneous or mildly heterogeneous and a pseudocapsule was present in one case. Pleomorphic types showed a markedly heterogeneous internal structure. Both myxoid and pleomorphic lesions-showed moderate or marked heterogeneous enhancement after contrast administration. Well-differentiated liposarcomas may be differentiated from other types of the tumor by their largely lipomatous appearance. The malignancy grade increases in parallel with tumor heterogeneity and contrast enhancement.

Primary soft tissue hydatid disease: report of two cases with MRI characteristics.

Abstract. Hydatid disease of the soft tissues forms a rare mass lesion of the extremities. Two cases of primary hydatid disease in soft tissues are presented with MR imaging findings. A cystic mass with multiloculated or multicystic appearance was identified on MR images in both cases. The lesions were surrounded by a rim with two layers representing a collageneous and a vascularized pericyst. The contrast-enhanced images demonstrated the vascularized component of the wall clearly in the first case. In diagnosis of hydatid disease and in its differentiation from other cystic lesions of the extremities, we think that the described MR appearances can be used confidently.

Magnetic resonance imaging of intramuscular haemangiomas with emphasis on contrast enhancement patterns

Fifteen patients with intramuscular haemangiomas were evaluated with magnetic resonance imaging (MRI). Phleboliths were demonstrated by plain films or CT in six cases, which are characteristic for haemangioma. MRI showed intermediate or slightly high signal intensity on T1-weighted spin-echo images, and overall extremely bright signal on T2-weighted images. Twelve patients had a heterogeneous signal intensity and serpentine pattern on all sequences. A draining vessel was identified in a patient with histologically confirmed diagnosis of arteriovenous type of hemangioma. In three cases with localized small lesions, the MR appearance on T1 and T2-weighted conventional spin-echo sequences was homogenous. Two of the three showed a serpentine pattern on contrast enhanced images. In a patient with a soft tissue mass suspected of representing a haemangioma, MRI may provide more specific information, regarding the characteristics and extent of the lesion than other imaging techniques. In small localized lesions, contrast enhanced MRI may also offer significant advantage, making the identification of serpentine pattern possible which is a characteristic morphological feature of haemangioma.

Musculoskeletal hydatid disease.

Hydatid disease is an infectious disease caused by the larval stage of the parasitic tapeworm Echinococcosis granulosus. Its distribution is worldwide. Although hydatid disease can develop in almost any part of the body, it is most commonly found in the liver and lung. Musculoskeletal involvement is rare. The radiological appearance of the hydatid disease of musculoskeletal system mimics tumors and other inflammatory conditions. Therefore preoperative diagnosis of musculoskeletal hydatid disease is sometimes difficult clinically and radiologically. On radiography, different radiographic changes may occur. In cases of osteolytic and inflammatory changes, it may mimic any variant of nonspecific or specific osteomyelitis. Bone erosion and destruction may lead to almost complete osteolysis, bone may distort, and on occasion, its radiologic appearances may be confused with those of a malignant bone tumor. Computed tomography (CT) is more accurate in delineating the area of destruction. The primary role of CT and magnetic resonance imaging is in the recognition of extraosseous spread of the hydatid disease within the soft tissues. This article reviews the pathological basis and the clinical and imaging features of musculoskeletal hydatid disease.

Spondyloepiphyseal Dysplasia Tarda with Progressive Arthropathy

Abstract: Spondyloepiphyseal dysplasia tarda with progressive arthropathy, described by Wynne-Davies et al., is a rare autosomal recessive disorder. It is characterised by generalised platyspondyly and epiphyseal involvement, with enlargement of both ends of the short tubular bones of the hands. Clinical features include onset in childhood, a disproportionately short stature and premature osteoarthritis. We describe the clinical and radiographic findings of a young woman suffering from spondyloepiphyseal dysplasia tarda with progressive arthropathy.

Intraosseous lipoma: radiological findings

OBJETIVO: Lipomas intra-osseos podem ser lesoes menos raras do que anteriormente sugerido na literatura. Frequentemente tem sido erroneamente diagnosticados como outras lesoes osseas benignas. A combinacao de tomografia computadorizada, ressonância magnetica e radiografia e essencial para reduzir as taxas de erro diagnostico. MATERIAIS E METODOS: Este estudo retrospectivo apresenta dez casos de lipoma intra-osseo. As idades dos pacientes variavam entre 25 e 80 anos, e seis deles eram do sexo feminino. Seis pacientes apresentavam dor ossea, enquanto quatro eram assintomaticos com lesoes descobertas casualmente. Os ossos afetados foram: femur (quatro pacientes), tibia (dois pacientes), calcâneo (um paciente), sacro (um paciente), osso iliaco (um paciente), osso navicular (um paciente). Todos os pacientes foram avaliados por meio de radiografia convencional, tomografia computadorizada e ressonância magnetica das regioes afetadas. RESULTADOS: Em todos os casos, as radiografias revelaram lesoes liticas bem delimitadas. Tanto a tomografia computadorizada como a ressonância magnetica foram bastante uteis para demonstrar gordura dentro do tumor. O padrao histologico de todos os tumores caracterizou-se por tecido adiposo maduro. CONCLUSAO: Lipoma intra-osseo e uma entidade bem definida que pode se desenvolver com variadas apresentacoes. Radiografias convencionais, isoladamente, nao podem diagnosticar essas lesoes. Entretanto, a tomografia computadorizada e a ressonância magnetica sao metodos bastante uteis nesses casos.

Clear cell chondrosarcoma: unusual radiologic appearances with histologic correlation

Abstract. Clear cell chondrosarcoma is a rare variant of the bone tumors with distinct radiologic and pathologic features. In this report two cases of clear cell chondrosarcomas with atypical radiologic appearances are presented. The findings of X-ray films and MRI are described with histologic correlation. In the first case the lesion showed a very expansile and long segment involvement of the humerus. In the second case the lesion was located in the diaphysis of the femur causing a large cortical destruction.

Mandibuloacral dysplasia with absent breast development

Mandibuloacral dysplasia is an autosomal recessive condition extensively reviewed elsewhere [Gorlin et al., 2001]. Manifestations include short stature, delayed cranial suture closure, mandibular hypoplasia, dysplastic clavicles, abbreviated club-shaped terminal phalanges, acroosteolysis, and atrophy of the skin over the hands and feet. First reported by Cavallazzi [1960], at least 30 cases have been published since then [Gorlin et al., 2001]. Novelli et al. [2002] demonstrated a mutation in LMNA-encoding lamin A/C. Hypogonadism, growth hormone deficiency, and insulin-resistant diabetesmellitus have been associated with some cases of mandibuloacral dysplasia [Gorlin et al., 2001]. To our knowledge this is the first case with absent breast development.

Multidetector-Row Computed Tomographic Angiography Findings of Musculoskeletal Tumors: Retrospective Analysis and Correlation with Surgical Findings

Background: Although magnetic resonance imaging (MRI) is a valuable method in staging musculoskeletal tumors, it may not give enough information on the association between the tumor and the main vascular structures adjacent to the tumor. In this respect, computed tomographic angiography (CTA) may be a useful alternative imaging technique. Purpose: To evaluate the effectiveness of CTA in determining vascular invasion in patients with musculoskeletal tumors and suspected vascular invasion by MRI, and to correlate the CTA findings with the surgical findings. Material and Methods: Twenty patients who had musculoskeletal tumors and lacked a fat plane between the tumor and adjacent vessels by MRI were included in this study. All patients were evaluated with CTA, and the CTA findings were reviewed by two radiologists to determine the presence of vascular invasion. Statistical analysis was carried out by using surgical findings as the gold standard. Results: There were nine women and 11 men (mean age 31 years) with either bone (n=9) or soft-tissue (n=11) tumors. Twelve patients without invasion according to the CTA examination were also surgically negative (true-negative cases). Of the eight patients with invasion shown by CTA, only three had adhesions and were considered surgically negative (false-positive cases). Five had invasions proven by surgery and were considered surgically positive (true-positive cases). Compared to the surgical findings, CTA had 100% sensitivity, 80% specificity, 62.5% positive predictive value, 100% negative predictive value, and 80% accuracy. Conclusion: CTA is a more accurate imaging technique than MRI in evaluating vascular invasion of musculoskeletal tumors, and provides valuable preoperative data.

Pitfalls in MR Imaging of Musculoskeletal Tumors

A wide range of musculoskeletal tumors and tumor-like conditions may be encountered when patients undergo radiologic examinations. Although MR imaging is a powerful medical imaging method that has been used extensively in the evaluation of musculoskeletal tumors, nontumoral or tumorlike lesions may have similar imaging findings. The imaging features of certain normal, reactive, benign neoplastic, inflammatory, traumatic, or degenerative processes in the musculoskeletal system may mimic malignant tumors. Misinterpretation of the imaging findings can lead to inappropriate clinical management of the patient. We review and describe the MR imaging characteristics of nontumoral bone lesions that are located in the marrow cavity, cortical bone, or in both, and soft tissue lesions that may be misinterpreted as sarcoma.