Biomedical subjects
Publications and source records attributed to S Lamer.
Paraganglioma of the filum terminale is a rare tumor but well described in the neurosurgery and pathology literature. Few MRI reports are mentioned. Paraganglioma, often misdiagnosed with ependymoma or schwannoma on MRI images, must be kept in mind, when a highly vascular lesion with serpentine vessels is observed.
RATIONALE AND OBJECTIVES: Nodal response to chemotherapy in head and neck squamous cell carcinoma depends on the vascularization. The authors assessed different techniques in detecting nodal vascularization. METHODS: Fourteen patients with head and neck tumor were included before surgical treatment. The largest metastatic lymph node (mean axial scanographic diameters 30 x 20 mm) was studied by color and pulsed Doppler, and dynamic magnetic resonance images, processed by factor analysis of medical image sequences (FAMIS), which estimates physiologic contrast enhancement kinetics (factors) and their spatial distributions (factor images). Results were compared with the histologic microvessel density (MVD). Using light microscopy, MVD was estimated by the vascular surface (by staining endothelial cells) to the stroma surface ratio x 100. RESULTS: Three factors were identified by FAMIS: a constant factor in necrosis, an earlier F1 factor and a later F2 factor in normal lymphoid areas and neoplastic stroma. Color flow signal was detected when the MVD was greater than 6.36. CONCLUSIONS: Only one model of vascularization was extracted by FAMIS, with no difference between neoplastic and spared lymphoid areas. The presence of color-flow signals could help predict the response of metastatic lymph nodes to chemotherapy.