[Postoperative evaluation of vascular bifurcation prostheses by means of helical CT]. / Valutazione postoperatoria delle protesi vascolari biforcate mediante TC spiroidea.

The dilatation of the vascular grafts is a well known phenomenon. It is usually evaluated by means of ultrasounds or, in selected cases, by CT scans or MRI; nevertheless its characteristics are far beyond to be fully recognized. Following our promising preliminary experience with helical CT as sole preoperative imaging for AAA, we have evaluated its reliability in the postoperative follow-up. We have studied 12 patients with aorto-iliac and 11 with aorto-femoral bypass for AAA, with a follow-up ranging between 1 and 3 years. A helical CT acquisition was performed during a single breath-holding with a 5-mm slice thickness, thus resulting in a 30 cm z-axis coverage. Axial images were reconstructed at 2-mm increments and used to generate high quality multiplanar reformatted (MPR) and three-dimensional (3D) surface rendered images. For each patient we evaluated the characteristics of the graft, the maximal diameters and the wall modifications. The average expansion was 28% at 1 year, stable at 2 years and then increased up to 44% at 3 years. Considering the different types of Dacron grafts, the dilatation was ranging between 22% and 46% (21 cases). The mean expansion was 31.3% and 29.5% for the trunk and for the branches of the graft respectively. No perigraft seroma nor anastomotic aneurysms were detected. A peculiar observation, both with and without contrast medium injection, was that all the grafts made on Dacron were not anymore depictable from the aortic wall after 1 year; the contrary was observed for the ePTFE grafts.

[Preoperative imaging of aneurysms of the abdominal aorta. Role of CT scan]. / Imaging preoperatorio degli aneurismi dell'aorta addominale. Ruolo della TC spiroidea.

The reliability of helical CT as sole preoperative diagnostic technique for abdominal aortic aneurysms (AAA) and its accuracy in detecting vascular anomalies in the abdominal region was evaluated retrospectively in 42 patients with asymptomatic AAA > 40 mm. A single breath-holding helical scan was performed with 5 mm slice thickness, during a single injection of contrast medium, resulting in a 20 cm z-axis coverage. Axial images were reconstructed and used to generate high quality multiplanar reformatted images. Digital subtraction angiography (DSA) was performed in the first 18 patients and then in case of associated peripheral vascular disease (6 patients). Helical CT exactly showed, in all cases, the proximal and distal extent of the AAA. The visceral vessels as well as the inferior vena cava and renal veins were always clearly depicted, showing anatomical variants or pathological involvement in 19 patients. DSA gave sufficient details on the distal run-off but did not allow a reliable visualization of the visceral branches, venous anomalies and true extent of AAA. In our experience helical CT should be considered as the sole method for preoperative imaging of AAA. It allows a complete and precise evaluation; it is fast, with low doses of radiations and does not require hospitalization.

[Spiral computed tomography in the diagnosis and staging of bronchopulmonary carcinoma]. / La tomografia computerizzata spiroidea nella diagnosi e stadiazione del carcinoma broncopolmonare.

Spiral or helical technology is a new computed tomographic technique based on the continuous acquisition of volumetric CT data during continuous x-ray beam rotation and continuous patient transportation at constant velocity. It has many advantages over conventional CT: the authors briefly review the basic principles of spiral CT and discuss the applications and the possible advantages in the assessment of lung cancer. The most important characteristics of spiral CT are rapid image acquisition, allowing a single-breath-hold scan of the lung, and the ability to obtain axial image reconstructions at arbitrary and overlapping intervals, thus allowing the detection of small lesions that otherwise would be inconspicuous because of respiratory misregistration or partial volume averaging. This leads to better identification of small pulmonary nodules and to high quality multiplanar reconstructions that can be useful in the study of mediastinal lymph nodes and the vascular and tracheobronchial spreading of lung cancer. Many of the spiral CT scanners allow for 40 sec extended spiral acquisition during a single-breath-hold, permitting the evaluation of the thorax and the upper abdomen. This usually includes the adrenals and the whole liver, thus allowing a rapid staging of thoracic neoplasms, with an accuracy higher than that of conventional CT.

[Biliary ileus. Considerations in surgical strategy]. / Ileo biliare. Considerazioni sulla strategia chirurgica.

Gallstone ileus is the small bowel obstruction due to one or more biliary calculi stopped in the enteric lumen. This older patient pathology is often associated with other comorbid medical conditions. Two clinical reports are analyzed and the various surgical procedures critically evaluated.

[Evaluation of the post-traumatic course of injuries of the Achilles tendon using computerized telethermography]. / Valutazione evolutiva delle tendinopatie achillee post-traumatiche mediante teletermografia computerizzata.

Follow-up of Achilles tendon injuries was carried out by means of computerized telethermography. The thermographic examination was performed at definite time intervals (a few hours, 15 days, 1 month, 3 months after acute traumatism) on 15 young patients subdivided into two different groups according to the tenonic injured site: proximal (6 cases) or insertional (9 cases). The study showed a satisfying correlation between hyperthermal level and clinical symptoms, thus allowing to define accurately the resolution or persistence (3 cases) of inflammatory process. In conclusion, the authors recommend the combined use of computerized telethermography and diagnostic US for a complete evaluation of Achilles tendon disorders according to their different evolutive phases.

Case report: imaging of bile duct hamartomas.

A rare case of multiple bile duct hamartomas of the liver has been evaluated with ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI) and digital subtraction angiography (DSA). The CT and angiographic features of the hamartomas described here differ significantly from previously reported cases. In addition, the MR appearance of these tumours is reported for the first time.

Sonographic characterization of an accessory fissure of the left hepatic lobe determined by omental infolding.

This article describes the sonographic appearance of a very common accessory fissure of the liver located on the inferior side of the left lobe. The fissure was recognized in about 5% of 800 consecutive subjects and showed variable appearance owing to different insertion levels on the inferior hepatic surface. It extended from the left hepatic border to the Rex's recess or alternatively to the falciform ligament or the gallbladder fossa and contained the hepatogastric and hepatoduodenal ligaments, as demonstrated by laparotomy in six cases. At surgery, there was no evidence of thickening of Glisson's capsule at the fissure site, thus suggesting that the fissure is the result of extrinsic remodeling of the left lobe by omental infolding.

Spiral CT of the abdomen after distention of small bowel loops with transparent enema in patients with Crohn's disease.

BACKGROUND: [corrected] To evaluate the capability of a computed tomographic (CT) technique that combines distention of the small bowel loops with a transparent enema with contrast-enhanced spiral CT of the abdomen in patients with Crohn's disease. METHODS: We evaluated the abdomen with spiral CT after distention of the small bowel loops with a transparent enema of methylcellulose in 40 patients consecutively referred for radiologic evaluation of Crohn's disease of the small bowel. Fluid was infused through a nasojejunal catheter with a peristaltic pump. Ultrasonography was used to prevent bowel overdistention and detect arrival of methylcellulose to the cecum. Contrast-enhanced spiral CT of the abdomen was then performed, and the degree of contrast enhancement and the thickness of the walls of the involved loops were evaluated. A series of 10 patients with retrograde distention of the last ileal loop from large bowel water enema was used as a control. The results of the CT were compared with those of conventional radiographic small bowel studies. RESULTS: The normal small bowel wall was 1.9-2.5 mm thick (mean = 2. 1 mm); density values of the normal enhanced wall varied between 25 and 60 HU (mean = 32 HU) and presented a homogeneous structure. Bowel segments involved by the disease were 4-12.5 mm thick (mean = 9.2 mm), had density values of 75-150 HU (mean = 105 HU), and showed a multilayered appearance. Compared with conventional radiography, CT detected longer lesions or additional segments involved by the disease process in 14 cases, 11 additional fistulas, two abscesses, and mesenteric changes in 21 cases. CONCLUSIONS: The small bowel CT enema technique provides good results in the study of patients with Crohn's disease and can be used to evaluate patients with advanced lesions.

[Magnetic resonance imaging of the small intestine and colon in Crohn's disease]. / La Risonanza Magnetica dell'intestino tenue e del colon nel morbo de Crohn.

Three normal volunteers and 20 patients with known Crohn's disease were examined with MRI--at 0.5 Tesla and with a superconductive magnet. Coronal T1-weighted GE images were mainly acquired, before and after i.v. Gd-DTPA injection in breath hold (TR 70 ms, TE 13 ms, FA 70 degrees). MR findings were compared with the results of small and large bowel enema. In 6 patients (30%) the abnormal loops were missed. In the other 14 patients (70%) MRI did depict the affected loops in the same sites as depicted by conventional radiography. The bowel wall was thickened (4-10 mm) in all patients. In 10 patients the thickened wall was markedly enhanced after Gd-DTPA injection. In 6 patients MRI demonstrated disease complications--i.e., stenoses, fistulae and abscesses--missed by conventional radiography. In 7 patients MRI showed the bowel to be more involved than demonstrated by conventional studies. Bowel wall thickening appeared to be a constant and reliable sign of disease. Wall enhancement was a less frequent sign but, when present, it was considered as characteristic as wall thickening. In the staging of Crohn's disease, MRI yields more pieces of information than conventional radiography and depicts the involvement of the intestinal wall and of its surrounding spaces.