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The aim of this work was to optimize the magnetic resonance angiography (MRA) technique for the selective study of the pulmonary veins. Twenty consecutive patients (13 men and 7 women; mean age: 30.5 years) were examined. MRA was performed with a 1 T superconductive magnet and the 3D time of flight (TOF) technique. Fast sequences (3D FISP: TR 58 ms, TE 6 ms, FA 20 degrees, matrix 192 x 256; and 2D FLASH: TR 44 ms, TE 10 ms, FA 30 degrees, matrix 192 x 256) were used. Coronal and sagittal images were submitted to MIP processing; presaturation pulses for the pulmonary arteries were located in the mediastinal region. In the right lung, 3D TOF on the coronal plane well showed 124 veins, while sagittal images showed 106 veins. In the left lung, 3D TOF on the coronal plane well showed 96 vessels, while sagittal images showed 44 vessels. In the right lung, 2D TOF on the coronal plane well showed 54 veins, while sagittal images showed 36 vessels. In the left lung, 2D TOF on the coronal plane well showed 22 vessels, while sagittal images showed 21 vessels. Therefore, 3D TOF yielded better results than 2D TOF (p < 0.05). To conclude, 3D TOF with contrast agent administration is a useful tool to study the pulmonary veins; those with a larger caliber are better depicted and the integration of coronal and sagittal images depicts more veins.

To assess the diagnostic and medicolegal contribution of Computed Tomography (CT) in patients with craniocerebral, maxillofacial, neck and spine gunshot wounds, we submitted to CT 106 patients with gunshot wounds examined over a 7-year period (February, 1988 to December, 1994). Twenty-four of them had craniocerebral injuries (23%), 9 maxillofacial (8%), 8 neck (8%) and 10 vertebral (9%) injuries. Emergency CT demonstrated the mechanism of the injury, the bullet path and site, the site of bone and/or metallic fragments, and damage extent. In all perforating cranioencephalic injuries (n = 7) intracerebral or extrathecal bone fragments were demonstrated adjacent to the bullet entrance and exit holes, respectively. In injury monitoring. CT showed injury evolution, retained fragments and complications, thus enabling damage extent assessment. High Resolution Computed Tomography (HRCT) was useful in locating minute orbitary retrobulbar and intraspinal fragments. Magnetic Resonance (MR) Imaging in postoperative patients proved a valuable tool to assess the extent of spinal cord damage. To conclude, CT is a useful technique to examine the patients with gunshot wounds, which helps plan adequate treatment and solve complex medicolegal problems.

This work was aimed at studying the origin of the epiaortic vessels with Magnetic Resonance Angiography (MRA). Twenty normal volunteers (mean age: 21.5 years) were examined with MRA with a superconductive magnet at 1 T (Impact). All volunteers were examined with a body coil and the time of flight (TOF) technique. The FISP 3D TONE sequence was used, with the following parameters: TR 46 ms, TE 10 ms, FA 20 degrees, ST 2.2 mm, matrix 192 x 256. The images, acquired on the axial plane with three presaturation pulses, were rotated according to the maximum intensity projection on the Z axis. To classify the images, a multiple choice card was used by a reader, with three diagnostic judgements for the different segments of the vessels (i.e., good, poor and not visualized). 3D TOF MRA permitted good visualization of the right and left common carotid in 80% and 77% of cases, of the right and left vertebral arteries in 55% and 50% of cases, of the left and right subclavian arteries in 47% and 62% of cases, and of the anonymous artery in 100% of cases. To conclude, our preliminary results indicate FISP 3D TOF MRA as the best noninvasive technique to study the origin of the epiaortic vessels.

The authors optimized the Magnetic Resonance Angiography (MRA) technique for the study of the different portions of the pulmonary artery-i.e., the common trunk, right and left main arteries and the lobar, segmental and subsegmental branches. Twenty volunteers were examined with MRA of the pulmonary arteries with a 1-T superconductive magnet (Impact) and the time-of-flight (TOF) technique. The volunteers were divided into two groups by age (ranges: 20-40 and 41-70 years). The trunk and main branches were studied with the 2D TOF technique, while 2D TOF images were compared with 3D TOF images in the study of peripheral (lobar, segmental and subsegmental) branches. The images were processed with the maximum intensity projection (MIP). In the statistical comparison between 2D and 3D TOF images, the t-test was used (p < 0.05). The 2D TOF images acquired on the sagittal oblique and coronal planes, with presaturation pulses, permitted optimal depiction of the trunk and of the right and left branches in all the volunteers. Both 2D and 3D TOF images yielded excellent images in the study of the lobar branches. In the volunteers under 40 years of age, 3D TOF sequences visualized the peripheral (segmental and subsegmental) vessels better than 2D TOF sequences (451 vs. 361); the difference was statistically significant. In the volunteers over 41 years of age, the ratio was reversed: 467 for 2D TOF vs. 362 for 3D TOF sequences; again, the difference was statistically significant. The correct integration of 2D and 3D TOF sequences, according to the different segments of the pulmonary artery and to patients' age, permitted the complete and accurate visualization of the pulmonary arteries with MRA.

The knowledge of wound ballistics and of wounding mechanisms is mandatory for the radiologist to interpret the CT findings of gunshot wounds. The severity of a bullet wound depends on the characteristics of the tissue it goes through, i.e., tissue elasticity, density, thickness of the wounded body part, the type of tissue, its specific gravity, internal cohesiveness and anatomical relationships, as well as on missile characteristics, i.e., mass, shape, fragmentation and deformation. Bullet velocity is certainly a major factor in wounding, but it is only one factor. Two major wounding mechanisms exist the crushing of the bullet-struck tissue (forming the permanent cavity) and radial stretching (forming a temporary cavity). Bullet "yaw" is defined as the angle between the long axis of the bullet and its flight path. The yaw is directly proportional to tissue crushing and stretching: the wider the yaw, the most severe tissue crushing and stretching and, therefore, the more severe tissue damage. The basic knowledge of these concepts is of the utmost importance to understand the CT findings of gunshot wounds and can help physicians study and treat gunshot wounds.

The Echinococcus granulosus disease, or hydatidosis, is endemic in Italy; it has high incidence in Sardinia, Latium and Apulia. The CT findings were examined of 120 patients with hydatid cysts in the liver, lungs, kidney, spleen, peritoneal cavity, retroperitoneal space, and spine. The smallest cyst demonstrated by CT had diameter = 1 cm; CT was also more sensitive than conventional radiology and US in demonstrating unusual localizations of hydatid cysts. CT findings alone allowed a correct diagnosis of the nature of the cyst to be made in 61.5% of cases and, when combined with immunodiagnostic tests for hydatid disease, in 94.5% of patients. Moreover, CT is essential not only for a correct treatment planning, but also during follow-up.