Andreas H. Gamroth

3d tof mr angiography of cerebral arteriovenous malformations after radiosurgery

To investigate the potential of three-dimensional time-of-flight MR angiography (MRA) to complement SE imaging, 18 patients with intracerebral arteriovenous malformations were prospectively followed after undergoing radiosurgery. Vessel occlusion after stereotaxic single high dose radiotherapy develops slowly. The MRA detected signs of nidus obliteration earlier and with a higher sensitivity than did SE imaging. Six months after radiosurgery, MRA showed a reduction of the nidus flow signals in nine patients and after 1 year it showed reduction in 15 of the 18 patients. As shown by MRA, the loss of flow signals was related to a reduction of the nidus size in 4 patients after 6 months and in 11 after 1 year. The SE imaging revealed a reduction of the nidus size in only two patients after 6 months and in eight after 1 year. The signal intensity of the feeding arteries was reduced in nine patients and that of the draining veins was reduced in six. The T2-weighted images exhibited white matter lesions in eight patients after 1 year. For complete follow-up, SE imaging should be performed together with MRA.

MR Velocity Measurement in the Pulmonary Arteries: A Comparative Study

Abstract The quantitative estimation of pulmonary hemodynamics is of clinical interest in various benign and malignant diseases of the lungs, especially in cases of preoperative planning of parenchymal resections and/or pulmonary arterial hypertension. In a comparative clinical study with 30 patients MR velocity measurements in the pulmonary arteries (main, right and left) were performed by the RACE-technique at 1.5 T. MR data were correlated (a) with the results of perfusion scintigraphy, (b) with pw-US doppler echo-cardiography, and (c) with right heart catheterization. MR-RACE showed good results for quantification of the relative right to left pulmonary arterial flow but was not able to indicate the correct absolute flow related to the results of right heart catheterization. Most probably this is due to interferences by overlapping vessels which are unavoidable in a projection technique. Better correlation with right heart catheterization can be expected using a two dimensional MR technique (e.g. „PHASE-MAPPING” or „PHASE-CONTRAST”) in patients without cardiac arrhythmias.

Radiodiagnostics and Radiotherapy

Radiology is one of the most important specializations in medicine for the detection, treatment, and follow-up of cancer diseases. Today, radiology not only encompasses conventional radiological methods of diagnosis and therapy, but also advanced techniques that make use of non-ionizing forms of radiation.

146. Primäre und sekundäre Brustwandtumoren — Neue bildgebende Verfahren

SummaryFor the diagnostic evaluation of chest wall tumours computed tomography, bone scintigraphy, sonography and magnetic resonance tomography as additional imaging methods are available. CT has the greatest clinical relevance; the most important advantage of CT is the exact topographic localization of the process and the evaluation of the soft tissue extension. A tumour specific diagnosis can only be expected on rare occasions. Bone scanning is the method of choice if destruction of the skeletal system is suspected.ZusammenfassungFür die diagnostische Beurteilung der Brustwandtumoren stehen als weiterführende Verfahren Computertomographie, Knochenszintigraphie, Echographie und Kernspintomographie zur Verfügung. Der CT kommt dabei die grösste Bedeutung zu. Ihr entscheidender Vorteil ist die exakte topographische Zuordnung des Prozesses und die genaue Bestimmung der Weichteilausdehnung. Eine artdiagnostische Beurteilung ist nur in besonderen Fällen möglich. Für den frühen Nachweis einer knöchernen Mitbeteiligung ist die Skeletszintigraphie die Methode der Wahl.