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D Vanel

Publications and source records attributed to D Vanel.

At least 19 recordsLinked to original sources
PubMed1992

Factor analysis of dynamic magnetic resonance imaging in predicting the response of osteosarcoma to chemotherapy.

RATIONALE AND OBJECTIVES: The response of osteosarcoma to preoperative chemotherapy was assessed using dynamic magnetic resonance imaging (MRI) processed by factor analysis of medical image sequences (FAMIS). METHODS: Forty-nine dynamic image sequences, acquired after a bolus injection of gadolinium in 10 patients, were processed by FAMIS: FAMIS is a means whereby physiologic contrast enhancement kinetics, called factors, and their spatial distribution, termed factor images, are estimated. Tumor volumes were measured on static MRIs, and factor images were compared with histologic maps of the resected specimens. RESULTS: A substantial increase in tumor volume reflected a poor response to chemotherapy. Viable tumor was precisely depicted by the early vascular factor image, reflecting rapid uptake by tumor vessels. This early uptake disappeared in all five patients who responded to chemotherapy, whereas it persisted in four of five nonresponders. CONCLUSION: FAMIS of dynamic MRI is proposed as a possible means of predicting the response of osteosarcoma to chemotherapy.

Adolescent↗
PubMed1992

Osteosarcoma: chemotherapy-induced changes at MR imaging.

Fifty-seven patients undergoing chemotherapy for osteosarcoma underwent evaluation with magnetic resonance (MR) imaging to identify changes related to a good or poor response. Spin-echo MR images obtained after preoperative chemotherapy were compared with images obtained before treatment. Histopathologic examination of each resected specimen was used to quantify the response. An increase in tumor volume and increased or unchanged edema were predictive of a poor histopathologic response (predictive values, 85%-92%). Decreased or unchanged tumor volume and a decrease in edema were poor predictors of a good response (predictive values, 56%-62%). Improved tumor demarcation, an increase in the size of areas of low signal intensity, and a decrease in joint effusion occurred independently of histopathologic response in almost half of the patients. With a subjective interpretation of MR images, poor respondents can be identified if an increase in tumor volume or no decrease in the amount of edema is seen. Subjective criteria do not contribute to the identification of good respondents.

Adolescent↗
PubMed1992

Adenoid cystic carcinoma of the head and neck: evaluation with MR imaging and clinical-pathologic correlation in 27 patients.

Twenty-seven adenoid cystic carcinomas (ACCs) of the head and neck in 27 patients were evaluated in a retrospective study based on findings at magnetic resonance (MR) imaging and pathologic and clinical examination. Clinical follow-up was obtained over a mean period of 6.3 years (range of follow-up, 3 months to 17 years); all patients underwent one to seven MR examinations. On T2-weighted images, lesions with low signal intensity corresponded to highly cellular tumors (solid subtype) with a poor prognosis; lesions with high signal intensity corresponded to less cellular tumors (cribriform or tubular subtype) with a better prognosis. MR images were not specific in differentiation of ACCs from other types of tumors; this result underscores the need for biopsy to ensure correct diagnosis. Local, intracranial, osseous, and perineural invasion was depicted, but because of its lack of specificity, MR imaging caused overdiagnosis of tumor extension, particularly perineural spread and bone abnormalities.

Adolescent↗
PubMed1992

Osteosarcoma after chemotherapy: evaluation with contrast material-enhanced subtraction MR imaging.

A new magnetic resonance (MR) technique, gadolinium-enhanced subtraction MR imaging, was developed to evaluate the response of patients with osteosarcoma to chemotherapy. Ten patients, who had received chemotherapy for osteosarcoma of the lower extremity, underwent MR imaging 3 days before surgery. After routine MR imaging was performed, subtraction MR was performed in the plane in which the tumor was best visualized. With gadopentetate dimeglumine (0.1 mmol per kilogram) on a standard MR console, subtraction images were created by subtracting precontrast images from gadolinium-enhanced T1-weighted images. The time of maximal tumoral vascular uptake was 1 1/2 minutes after injection, and, therefore, the subtracted image obtained at this time was used for evaluation of viable tumor. Independently, radiologists and histopathologists examined their respective studies for viable tumor to differentiate responders from nonresponders. Four of 10 osteosarcomas were classified as good responders because they appeared as nonenhancing masses, with or without enhancing thin lines, or small nodules (< or = 3 mm wide). At histopathologic examination, all were good responders with less than 3% viable tumor. Six of 10 osteosarcomas were classified as nonresponders because they appeared as enhancing high-signal-intensity masses measuring more than 3 mm in width. Five tumors had between 18% and 43% viable tumor cells.

Adolescent↗
PubMed1992

Imaging in the follow-up of soft tissue tumors.

Local recurrences of aggressive soft tissue tumors are frequent and very difficult to detect clinically after surgery and radiation therapy. Ultrasound is limited because the skin is thick. On contrast-enhanced CT, both scars and recurrences increase their signal. MRI is the best technique, and the only one we presently use in the detection of recurrent tumors. We are reporting 511 follow-up examinations in 182 patients after tumor removal. All patients had histologic confirmation or at least 6 months follow-up. There were 164 malignant tumors and 18 cases of aggressive fibromatosis.

Contrast Media↗
PubMed1991

Femoral infarction following intraarterial chemotherapy for osteosarcoma of the leg: a possible pitfall in magnetic resonance imaging.

Bone infarction of the distal femur is reported in two patients with osteosarcoma of the leg (1 tibia, 1 fibula) treated by preoperative chemotherapy including intraarterial chemotherapy (IAC) by Cis-platinum. Both patients were examined by magnetic resonance imaging before chemotherapy and again prior to limb salvage surgery. The location of these lesions in the distal femur must suggest bone infarction especially if the tumor has decreased in size under treatment.

Adult↗
PubMed1991

Case report 670: Chondroblastoma maxillary sinus.

A benign chondroblastoma of the left maxillary sinus developed in a 14-year-old girl. Roentgenographic examination showed an expanding, well-defined, calcified tumor. Facial and skull chondroblastomas may be related to primary or secondary centers of enchondral ossification, and therefore they may derive from the cartilage of growth plates [3]. Initial biopsy was inconclusive, but after surgical removal a histological diagnosis was made.

Adolescent↗
PubMed1991

[Choroid metastasis in a case of urothelial carcinoma metastatic from the bladder].

A 40 year old male, presented with a left choroidal metastases, 2 month after a radical cystectomy for an infiltrating transitional cell carcinoma of the bladder. This localisation was associated with disseminated metastasis which failed to respond to chemotherapy. The patient died within one month. The review of the literature confirms the poor prognosis of choroidal metastases in patients with transitional cell carcinoma of the bladder.

Adult↗
PubMed1991

Magnetic resonance imaging of the wrist.

Magnetic resonance imaging is one of the newest diagnostic techniques for evaluating the complex anatomy of the wrist. It is the only diagnostic modality that can directly depict abnormalities within the ligaments of the wrist and the TFC complex. Pathologic processes involving bone and soft tissue can also be demonstrated.

Bone and Bones↗
PubMed1989

[Diagnosis of disorders of the pharynx and larynx].

The new imaging techniques, such as computerized tomography and, more recently, magnetic resonance imaging, have thoroughly modified the diagnostic approach to tumors of the pharynx and larynx. The extension in depth of these tumors can now be directly visualized, and the key-areas (HTE space, paraglottic space, cartilages and subglottic area), which enable the best treatment to be chosen, are analyzed. These techniques are indispensable before reaching any decision on conservative surgery.

Humans↗
PubMed1989

Clinical and radiologic analysis of 13 cases of primary neuroectodermal tumors of bone.

Radiographs and clinical charts were reviewed in a series of 13 cases of primary neuroectodermal bone tumors, involving 9 males and 4 females, aged from 3 to 32 years (average: 15 years). The average delay between the onset and diagnosis was 5 months. Fever and other systemic symptoms were present in 6 cases; in 4 cases a fracture was the mode of presentation. Seven patients had metastases (4 involving bone) at the time of presentation. Only one patient is still alive after 5 years. In the 10 patients who died as a direct result of the tumor, death occured on average 8 months following diagnosis if metastases were present initially, and 36 months after the diagnosis otherwise. Tumors predominantly involved the leg (7 cases), the pelvis (2 cases), and the humerus (2 cases), the involvement being both diaphyseal and metaphyseal. The radiologic appearance is that of an aggressive, poorly demarcated tumor, with cortical destruction, periosteal reaction and soft tissue invasion. Comparison with Ewing sarcoma shows little radiologic or clinical difference, except for a poorer prognosis in neuroectodermal bone tumors. Both bone tumors may have a similar neuroectodermal origin, with Ewing sarcoma representing the undifferentiated variety.

Adolescent↗
PubMed1989

[The value of magnetic resonance imaging in the surveillance of fibromatosis. A study of 10 cases].

Retrospective study of 10 patients followed for fibromatosis after initial treatment by magnetic resonance imaging. There is a close correlation between an intense signal on weighted T2 images and tumour recurrence. Inversely, a low signal on the weighted T2 image indicated fibrotic sequelae without tumour recurrence. The examination should commence with the weighted T2 sequence. The injection of contrast medium may be an alternative.

Adult↗
PubMed1989

[Response of bone metastases to medical treatment: definition of evaluation criteria and classification trials].

Bone metastases are very frequent. Some are sensitive to the action of anticancer drugs. However, there is as yet an unsolved methodological problem in the evaluation of response to these drugs. The uniquely radiological UICC criteria are quite insufficient, in as much as they appear with a long delay and sometimes give erroneous results. In this work we give a brief review of biological and clinical knowledge about bone metastases, and we attempt to give an array of the possible evaluation criteria and their respective value. We propose as a working hypothesis a classification of responses taking into account the criteria: the urinary hydroxyproline to urinary creatinine ratio, the serum dosage of bone isoenzyme of alkaline phosphatase and propeptide of type III procollagen (P III NP), and as an essential element, an analysis of all available imaging techniques. A visual study of bone scintillation scans must precede that of radiographs and, when possible, it must be associated to computerized scintillation scanning. When metastasis are located to the pelvis, the vertebral column, or the sternum, a CT scan or better, a nuclear magnetic resonance study (IRM), is indispensable in order to have a direct measure of the tumor extension to soft tissues. Furthermore, in the case of isolated metastases, one of these imaging techniques allows a diagnostic biopsy. Finally an analysis of response at the bone level will always be associated with a measure of their duration and an evaluation of metastases to other sites.

Acid Phosphatase↗
PubMed1988

The role of magnetic resonance imaging in the evaluation of Ewing sarcoma. A report of 27 cases.

The experience with magnetic resonance imaging (MRI) in 27 patients with Ewing sarcoma is reported and compared with computed tomography (CT) and plain films. Plain radiography proved to be the best imaging method to asses probable histological diagnosis in all cases (n = 6). For the evaluation of chemotherapeutic response (n = 4), CT and MRI gave the same information about the variation in size of the tumor. In this small series, the high signal in T2 weighted images was not altered significantly by therapy. In preoperative evaluation (n = 14), MRI gave better information than CT of soft tissue involvement and extension within the bone marrow in two cases each. The ability of MRI to accurately define extension through the epiphyseal plate in two cases permitted limb salvage which otherwise would not have been possible. In the long-term follow-up (n = 12), three patients without recurrence one year after therapy showed a low signal in the surgical area in T2 weighted images. Nine patients had a high signal in T2 weighted images: four were reactive lesions, two had obvious recurrence, and one was a hematoma. In the two remaining cases plain films and CT were normal, in the presence of both active tumor and reactive lesions. It was not possible with MRI to differentiate active tumor from reactive change, even after Gd-DTPA infusion.

Adolescent↗