Frank Ramon | University of Antwerp (original) (raw)

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Papers by Frank Ramon

Research paper thumbnail of Five years experience in musculoskeletal magnetic resonance imaging on a 0.5 T imager

European Journal of Radiology, 1992

Research paper thumbnail of Magnetic resonance imaging of cartilaginous tumors: is it useful or necessary?

Skeletal radiology, 1996

A retrospective study was undertaken to compare the diagnostic accuracy of plain radiography and ... more A retrospective study was undertaken to compare the diagnostic accuracy of plain radiography and magnetic resonance (MR) imaging in the diagnosis of cartilaginous tumors. The study population consisted of 68 patients with a histologically proven cartilaginous tumor. For each lesion, a comparative analysis of "plain radiography" versus "plain radiography together with MR study" was performed by two radiologists together. Recently reported literature data were used as criteria by which to define accuracy rating. MR imaging improves accuracy in diagnosing low-grade chondrosarcomas. Since osteochondromas have a characteristic appearance on plain films, MR imaging contributes only in the diagnostic workup of cases in which malignant transformation is suspected.

Research paper thumbnail of Calcific tendinitis of the vastus lateralis muscle

Skeletal Radiology, 1991

Three cases of calcific tendinitis occurring at an unusual site (vastus lateralis tendon) are des... more Three cases of calcific tendinitis occurring at an unusual site (vastus lateralis tendon) are described. Findings on conventional radiography and computed tomography together with the clinical history are characteristic for this disorder and reflect its natural evolution. The actual role of magnetic resonance imaging seems limited to excluding neoplasm and to demonstrating inflammatory changes better in the early stages of disease.

Research paper thumbnail of Chondrosarcoma in a patient with relapsing polychondritis

Research paper thumbnail of Magnetic resonance imaging of cartilaginous tumors: a retrospective study of 79 patients

European Journal of Radiology, 1995

Objective: Hyaline cartilaginous tumors are characterized by extremely high signal intensity on T... more Objective: Hyaline cartilaginous tumors are characterized by extremely high signal intensity on T2-weighted images. Recently, some distinctive MR features of cartilaginous bone tumors were reported in small series. Low signal intensity septa surrounding high signal intensity cartilage lobules were seen on T2-weighted images in low-grade chondrosarcomas. On spin-echo Tl-weighted images after Gd contrast injection, marked 'septal' or 'ring-and-arc' enhancement was observed in low-grade chondrosarcomas and enchondromas. The purpose of this study was to determine sensitivity and specificity of these MR findings in diagnosis of cartilaginous tumors, and to assess the value of MR in diagnostic workup of these lesions. Materials and methods: Retrospective evaluation of MR findings in 79 cartilaginous tumors and in 79 non-cartilaginous tumors. All lesions were biopsy proven. Each MR examination was independently reviewed by two experienced radiologists without knowledge of clinical data, radiographic and/or CT findings, or histological diagnosis. All lesions were evaluated for morphology (lobular or non-lobular), presence of a high signal intensity mass on T2-weighted images, presence of low signal intensity septa separating high signal intensity lobules on T2-weighted images, and evidence of septal ('ring-and-arc') enhancement. Results: None of the reviewed parameters is useful in diagnosing osteochondromas. Since osteochondromas have a characteristic appearance on plain radiography, the value of MR imaging in the workup of these lesions remains limited. MR findings in enchondromas have a low specificity and a low sensitivity. Low-grade chondrosarcomas, often hard to diagnose on plain radiography and difficult to differentiate from enchondromas, are characterized by the MR tandem of'low signal intensity septa on T2-weighted images' together with 'septal or ring-and-arc enhancement' (sensitivity 92.3%, specificity 76.5%). High-grade chondrosarcomas are easily recognized on plain radiography. Conclusions: In differentiating cartilaginous from non-cartilaginous tumors, MR features are highly specific but lack sensitivity. Grading potentials of MR parameters are promising due to the high accuracy in diagnosing low-grade chondrosarcomas.

Research paper thumbnail of Medical Imaging of the Lumbar Facet Joint

Surgery of the Spine and Spinal Cord, 2016

Research paper thumbnail of Five years experience in musculoskeletal magnetic resonance imaging on a 0.5 T imager

European Journal of Radiology, 1992

Research paper thumbnail of Magnetic resonance imaging of cartilaginous tumors: is it useful or necessary?

Skeletal radiology, 1996

A retrospective study was undertaken to compare the diagnostic accuracy of plain radiography and ... more A retrospective study was undertaken to compare the diagnostic accuracy of plain radiography and magnetic resonance (MR) imaging in the diagnosis of cartilaginous tumors. The study population consisted of 68 patients with a histologically proven cartilaginous tumor. For each lesion, a comparative analysis of "plain radiography" versus "plain radiography together with MR study" was performed by two radiologists together. Recently reported literature data were used as criteria by which to define accuracy rating. MR imaging improves accuracy in diagnosing low-grade chondrosarcomas. Since osteochondromas have a characteristic appearance on plain films, MR imaging contributes only in the diagnostic workup of cases in which malignant transformation is suspected.

Research paper thumbnail of Calcific tendinitis of the vastus lateralis muscle

Skeletal Radiology, 1991

Three cases of calcific tendinitis occurring at an unusual site (vastus lateralis tendon) are des... more Three cases of calcific tendinitis occurring at an unusual site (vastus lateralis tendon) are described. Findings on conventional radiography and computed tomography together with the clinical history are characteristic for this disorder and reflect its natural evolution. The actual role of magnetic resonance imaging seems limited to excluding neoplasm and to demonstrating inflammatory changes better in the early stages of disease.

Research paper thumbnail of Chondrosarcoma in a patient with relapsing polychondritis

Research paper thumbnail of Magnetic resonance imaging of cartilaginous tumors: a retrospective study of 79 patients

European Journal of Radiology, 1995

Objective: Hyaline cartilaginous tumors are characterized by extremely high signal intensity on T... more Objective: Hyaline cartilaginous tumors are characterized by extremely high signal intensity on T2-weighted images. Recently, some distinctive MR features of cartilaginous bone tumors were reported in small series. Low signal intensity septa surrounding high signal intensity cartilage lobules were seen on T2-weighted images in low-grade chondrosarcomas. On spin-echo Tl-weighted images after Gd contrast injection, marked 'septal' or 'ring-and-arc' enhancement was observed in low-grade chondrosarcomas and enchondromas. The purpose of this study was to determine sensitivity and specificity of these MR findings in diagnosis of cartilaginous tumors, and to assess the value of MR in diagnostic workup of these lesions. Materials and methods: Retrospective evaluation of MR findings in 79 cartilaginous tumors and in 79 non-cartilaginous tumors. All lesions were biopsy proven. Each MR examination was independently reviewed by two experienced radiologists without knowledge of clinical data, radiographic and/or CT findings, or histological diagnosis. All lesions were evaluated for morphology (lobular or non-lobular), presence of a high signal intensity mass on T2-weighted images, presence of low signal intensity septa separating high signal intensity lobules on T2-weighted images, and evidence of septal ('ring-and-arc') enhancement. Results: None of the reviewed parameters is useful in diagnosing osteochondromas. Since osteochondromas have a characteristic appearance on plain radiography, the value of MR imaging in the workup of these lesions remains limited. MR findings in enchondromas have a low specificity and a low sensitivity. Low-grade chondrosarcomas, often hard to diagnose on plain radiography and difficult to differentiate from enchondromas, are characterized by the MR tandem of'low signal intensity septa on T2-weighted images' together with 'septal or ring-and-arc enhancement' (sensitivity 92.3%, specificity 76.5%). High-grade chondrosarcomas are easily recognized on plain radiography. Conclusions: In differentiating cartilaginous from non-cartilaginous tumors, MR features are highly specific but lack sensitivity. Grading potentials of MR parameters are promising due to the high accuracy in diagnosing low-grade chondrosarcomas.

Research paper thumbnail of Medical Imaging of the Lumbar Facet Joint

Surgery of the Spine and Spinal Cord, 2016

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