Ludovico Dalla Palma

Magnetic resonance imaging in right ventricular dysplasia

Fifteen patients with right ventricular dysplasia were investigated by T1-weighted spin- and gradient-echo pulse sequences, using a protocol that enabled both a subjective analysis of myocardial signal intensity and a quantitative/qualitative analysis of right and left ventricular function. In 8 patients, 3 investigators independently recognized abnormally hyperintense areas in the anatomic sites usually affected by the disease. In 7 of these patients, these areas showed an overlap with a-dyskinetic areas imaged by both magnetic resonance imaging (MRI) and echocardiography. In 1 patient who underwent a cardiac transplant, MRI of the explanted heart showed an excellent correlation between the distribution of the lesions and the in vivo/in vitro features. The data were compared with those from an equivalent sample of patients affected by dilated cardiomyopathy. In the latter patients, no focal hyperintensities were attributed to any anatomic sites in the right ventricule, and no focal a-dyskinetic foci were observed. Furthermore, the 2 groups of patients were significantly different in regard to dimensional and functional quantitative parameters. The results suggest that MRI is useful in integrating echocardiographic data and can be helpful in diagnosing this disease in late stages.

Breast tomography with synchrotron radiation: preliminary results*

A system for in vivo breast imaging with monochromatic x-rays has been designed and built at the synchrotron radiation facility Elettra in Trieste (Italy) and will be operational in 2004. The system design involves the possibility of performing both planar mammography and breast tomography. In the present work, the first results obtained with a test set-up for breast tomography are shown and discussed. Tomographic images of in vitro breasts were acquired using monochromatic x-ray beams in the energy range 20-28 keV and a linear array silicon pixel detector. Tomograms were reconstructed using standard filtered backprojection algorithms; the effect of different filters was evaluated. The attenuation coefficients of fibroglandular and adipose tissue were measured, and a quantitative comparison of images acquired at different energies was performed by calculating the differential signal-to-noise ratio of fibroglandular details in adipose tissue. All images required a dose comparable to the dose delivered in clinical, conventional mammography and showed a high resolution of the breast structures without the overlapping effects that limit the visibility of the structures in 2D mammography. A quantitative evaluation of the images proves that the image quality at a given dose increases in the considered energy range and for the considered breast sizes.

Iopamidol in urography

The radiographic results obtained in urography with iopamidol, a new low osmolality contrast medium, given to 50 patients with normal renal function and 42 patients with impaired renal function, have been evaluated and compared with those obtained with ionic media of current use (meglumine sodium diatrizoate and sodium iothalamate). Based on this comparison, the authors believe there are no significant radiographic advantages to iopamidol.

Breast tomography with synchrotron radiation

A feasibility study of breast CT with synchrotron radiation is currently being carried on at Elettra, the Trieste synchrotron radiation facility. Breast CT cannot be implemented easily with conventional radiographic tubes, due to the high dose that would be delivered to the breast by a polychromatic X-ray spectrum. The possibility of tuning the beam energy, available at a synchrotron radiation beamline, allows a significant reduction in the delivered dose, and at the same time the use of monochromatic beams avoids beam hardening artifacts on the reconstructed image. Images of in vitro breast tissue samples have been acquired by means of a high efficiency linear array detector coupled to a VLSI single photon counting readout electronics. The pixel width, determining the pixel size of the reconstructed image, is 200 micrometers , while the pixel height, determining the CT slice thickness, is 300 micrometers . Tomograms have been reconstructed by means of standard filtered backprojection algorithms. Images of normal and pathologic breast tissue samples show a good visibility of glandular structure. The delivered dose was in all cases comparable to the one delivered in clinical planar mammography. Due to the promising results we obtained, in vivo studies are under evaluation.

The Halley Project

The refresher courses are to be held in the aforementioned countries under the patronage of the E A R in collaboration with the European societies of the respective subdisciplines. The courses will be organised by a travelling faculty and taken to the individual countries, whereby the refresher courses will be the same in each country. The C E R E E Committee will design the refresher course programme and indicate a number of teachers suitable for the various topics (with a minimum of two lecturers per topic), so as to allow a regular staging of the course in all countries.