Magnetic resonance (MR) imaging was performed on 40 patients with intracranial tumors, before and after intravenous administration of gadolinium-DTPA (Gd-DTPA). Precontrast studies included a comprehensive protocol of spin-echo sequences. Tumors were visualized on precontrast images either directly or indirectly by anatomic distortion caused by the mass. However, differentiation of the tumor from adjacent tissues was possible in only 17 of 40 cases. Delineation of the tumor was best on precontrast, T2-weighted images. After administration of Gd-DTPA (0.1 mmol/kg), increased signal intensity from the tumor was observed in all patients. The localized increase in signal intensity in the tumor considerably improved the tumor delineation in 36 of 40 patients. Whereas most of the meningiomas, neuromas, and adenomas could be delineated prior to administration of contrast material if appropriate pulse sequences were applied, glioblastomas and intracranial metastases required Gd-DTPA administration for diagnostically sufficient tumor display.
This study examines the effect of the NMR contrast medium gadolinium-DTPA on image contrast in cerebral tumours. Sixteen patients with space-occupying cerebral lesions were examined on a 0.35 Tesla superconducting scanner, using a T1-weighted spinecho sequence prior to and after the intravenous application of gadolinium-DTPA. In 8 patients T2-weighted spinecho-sequences were obtained before the administration of contrast. The tomograms were evaluated visually and according to quantitative criteria. The use of gadolinium-DTPA helps to evaluate the blood-brain barrier and improves diagnosis by differentiating tumour tissue from edema and from normal brain tissue.
In an initial clinical trial we examined the tolerance and the influence exercised on signals in nuclear magnetic resonance tomography by gadolinium-DTPA. In an open study, 4 dosages between 0.005 and 0.25 mmol Gd-DTPA/kg body-weight were tested on 5 healthy volunteers each. To ensure renal elimination of Gd-DTPA, NMR images were produced (0.35 T Magnetom) visualising the kidneys and urinary bladder before and more than 60 minutes after application of the contrast medium. The article shows in what manner the image is influenced by the dosage of the contrast medium and also by the time interval elapsing between injection of the contrast medium and production of the NMR tomogram. - Finally, first clinical results of NMR tomography contrast medium application are demonstrated in the case of 5 patients with cerebral tumours.
Two hundred and eighty-six patients suspected of having pancreatic disease were examined by computed tomography, Octoson and conventional ultrasound. Computed tomography with angio-CT had the highest sensitivity (87.4%). The Octoson, with a sensitivity of 77.16% was better than conventional ultrasound, which had a sensitivity of 65.35%. Specificity for CT was 91.2%, for the Octoson 88.67% and conventional ultrasound 85.5%. The better results of the Octoson examination are due to the thin air gap when the patient is prone and the greater focal length of the large transducer and the somewhat more stable focus.
The limitations and advantages of the different ultrasonic breast-scanner (manual and automated) were described, likewise experiences with an automated waterpath scanner (Octoson). For breast cancer screening the automated scanner seems to be an acceptable concept, because it manifests the breast with an excellent anatomic view. In addition the mamma is in a stable position and the examination can be properly delegated. The manual examination can be used as an additional examination. Ultrasound scan can be correlated with the manual examination and a cyst can be punctured under ultrasonic control. Essential technological improvements are to be expected by both ultrasonic systems.
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