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Roberto Passariello

Publications and source records attributed to Roberto Passariello.

At least 55 records · Page 3Linked to original sources
PubMed2004

Focal liver lesions in the cirrhotic patient: multislice spiral CT evaluation.

Imaging of the cirrhotic patient is a very difficult task due to the several morphologic and structural alterations that occur in the hepatic parenchyma. The presence of areas of fibrosis and regenerative nodules, often associated with haemodynamic alterations due to the portal hypertension, can make the identification of hepatocellular carcinoma very difficult or, in many cases, simulate the presence of tumour. Despite the use of state-of-the-art equipment and optimised study protocols, computed tomography (CT) has poor sensitivity for the detection of hepatocellular carcinoma. The present article illustrates the spiral CT findings that most often can be found in the evaluation of cirrhotic patients. In particular, the authors illustrate the CT patterns of regenerative nodules, dysplastic nodules, hepatocellular carcinomas and of all lesions that may mimic hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed2004

Multidetector computed tomography of the coronary arteries.

Over the past decades, the feasibility of non-invasive coronary imaging has been explored using different modalities, such as magnetic resonance and electron beam computed tomography. Despite encouraging initial results, neither technique is yet considered suitable for routine clinical use. Recent developments in multidetector computed tomography have expanded the potential of contrast-enhanced spiral computed tomography coronary angiography. Promising results have been published with the use of 4-slice spiral computed tomography; however, cardiac motion and calcium deposits in the artery wall rendered a substantial number of scans inadequate for interpretation. Recently, a new generation of scanners, equipped with more and thinner detector rows (8 and 16 detectors) and an increased rotation speed, have been introduced. These technical advances will have a significant impact on cardiac imaging: at an increased gantry rotation rate, up to 32 slices can be acquired in 1 s. The improved spatial and temporal resolutions have led to the opportunity of acquiring high-quality images of the entire heart within a single breath-hold.

Calcinosis↗
PubMed2003

Transrectal ultrasound color Doppler in the evaluation of recurrence of anal canal cancer.

OBJECTIVE: aim was to obtain elements for a differential diagnosis between post-radiation fibrosis and residual tumor or local relapse in anal canal cancer through detection of presence/absence of intralesional blood flow. Transrectal ultrasound and color Doppler were compared. METHODS: 43 patients underwent transrectal ultrasound sonography and color Doppler before and after therapy to assess intralesional blood flow and flow pattern (spotty and linear signals). All diagnostic imaging results were compared to histological analysis. Specificity was submitted to statistical analysis using McNemar test. RESULTS: before therapy 34 lesions (79%) showed color signal; no signal in 9 (21%), which were excluded from our analysis. Eighteen of the 34 patients considered, presented complete response to therapy, 14 partial response and two no response. After therapy, signal disappeared in 17 patients (94%); one false-positive (6%) presented spotty signals; 16 of 34 patients presented changed color signal. Color Doppler showed higher specificity than grey scale transrectal ultrasound in the differentiation of fibrosis from tumor. Response was confirmed by histological examination, considered gold standard. McNemar test demonstrated the significance of color Doppler (P < 0.0001). CONCLUSION: color Doppler considerably increases transrectal ultrasound specificity in differentiating tumor relapse from fibrosis in anal canal cancer.

Anal Canal↗
PubMed2003

Hepatocellular carcinoma: detection with triple-phase multi-detector row helical CT in patients with chronic hepatitis.

PURPOSE: To evaluate whether the use of two arterial phase image acquisition series, when combined with portal venous phase imaging at multi-detector row helical computed tomography (CT), would be superior enough to use of a single arterial phase image acquisition series to warrant the increased radiation dose. MATERIALS AND METHODS: Multi-detector row CT was performed in 77 patients with 140 foci of hepatocellular carcinoma (HCC). A triple-phase protocol that included an early arterial phase, a late arterial phase, and a portal venous phase was performed. Images were analyzed separately by three radiologists to document the presence and number of HCC nodules. Separate reading sessions were performed for images from the early arterial phase, images from the late arterial phase, images from both arterial phases combined, and images from all three phases. Sensitivity and positive predictive values were calculated for each reading session. RESULTS: The average sensitivity and positive predictive values, respectively, for the detection of HCC were 48.5% and 96.4% for early arterial phase images, 87.1% and 94.0% for late arterial phase images, 87.1% and 94.0% for images from both arterial phases, and 88.5% and 93.4% for images from all three phases. Analysis of images from both arterial phases together yielded no improvement in either sensitivity or positive predictive value compared with analysis of late arterial phase images alone. Analysis of the combination of late arterial and portal venous phase images resulted in the highest sensitivity value. CONCLUSION: The acquisition of images during two arterial contrast phases does not provide additional benefit over timed conventional biphasic CT technique.

Aged↗
PubMed2003

Detection of colorectal lesions: lower-dose multi-detector row helical CT colonography compared with conventional colonoscopy.

PURPOSE: To compare the performance of lower-dose multi-detector row helical computed tomographic (CT) colonography with that of conventional colonoscopy in the detection of colorectal lesions. MATERIALS AND METHODS: One hundred fifty-eight patients underwent multi-detector row helical CT colonography (beam collimation, 4 x 2.5 mm; table feed, 17.5 mm/sec; voltage, 140 kV; and effective dose, 10 mAs) followed by conventional colonoscopy. Conventional colonoscopy served as the reference standard. Two radiologists interpreted CT colonographic images to assess the presence of polyps or carcinomas. Sensitivity was calculated on both a per-polyp and a per-patient basis. In the latter, specificity and positive and negative predictive values were also calculated. Weighted CT dose index was calculated on the basis of measurements obtained in a standard body phantom. Effective dose was estimated by using commercially available software. RESULTS: CT colonography correctly depicted all 22 carcinomas (sensitivity, 100%) and 52 of 74 polyps (sensitivity, 70.3%). Sensitivity for detection was 100% in all 13 polyps 10 mm or larger in diameter, 83.3% in 20 of 24 polyps 6-9 mm, and 51.3% in 19 of 37 lesions 5 mm or smaller. With regard to the per-patient analysis, CT colonography had a sensitivity of 96.0%, a specificity of 96.6%, a positive predictive value of 94.1%, and a negative predictive value of 97.7%. The total weighted CT dose index for combined prone and supine acquisitions was 2.74 mGy. The simulated effective doses for complete CT colonography were 1.8 mSv in men and 2.4 mSv in women. CONCLUSION: Lower-dose multi-detector row helical CT colonography ensures substantial dose reduction while maintaining excellent sensitivity for detection of colorectal carcinomas and polyps larger than 6 mm in diameter.

Aged↗
PubMed2003

Intrahepatic aneurysmal portohepatic venous shunt: embolization with a tissue adhesive solution.

PURPOSE: To report the endovascular treatment of an intrahepatic portosystemic venous shunt (IPSVS) using a tissue adhesive solution. CASE REPORT: A 40-year-old woman without diagnosed liver disease presented for evaluation of vague abdominal pains. A latent portosystemic encephalopathy was diagnosed only during hospitalization, when ultrasound examination disclosed a venous-venous right hepatic communication. The patient was treated with selective percutaneous embolization using a tissue adhesive after blocking the lesion's venous inflow and outflow tracts. The result was excellent, and the patient recovered completely in a few days. After 5 months, the patient is asymptomatic and event-free. CONCLUSIONS: Large IPSVS may be successfully treated percutaneously using a tissue adhesive solution, avoiding a more invasive procedure.

Adult↗
PubMed2003

Type A aortic dissection developing during endovascular repair of an acute type B dissection.

PURPOSE: To describe an extension of type B dissection into type A during endoluminal treatment of acute type B dissection. CASE REPORT: A 57-year-old man with acute type B dissection underwent endovascular repair using 2 Excluder stent-grafts. Before releasing the second stent-graft, the patient complained of mild central chest pain, headache, and visual flashes, but no hemodynamic changes were noticed. An angiogram, performed soon afterwards, showed a retrograde extension of the dissection through the aortic arch involving both the left carotid artery and the ascending aorta. The procedure was completed, and the patient was transported to the operating room where the proximal ascending aorta was replaced. Spiral computed tomographic angiography performed 2 weeks after the procedure showed complete exclusion of the primary entry tear. At 6-month follow-up, the patient was asymptomatic; the left carotid artery dissection had disappeared. CONCLUSIONS: Endovascular repair of acute type B dissection is technically feasible, but longer experience will help prevent technical complications.

Aortic Dissection↗
PubMed2003

MR imaging of the small bowel using polyethylene glycol solution as an oral contrast agent in adults and children with celiac disease: preliminary observations.

OBJECTIVE: The purpose of our report is to describe morphologic abnormalities of the small bowel in a population of patients with known celiac disease using MR imaging with polyethylene glycol solution as an oral contrast agent. CONCLUSION: Polyethylene glycol-enhanced MR imaging is a noninvasive (no ionizing radiation is used), feasible, and reproducible imaging technique in both adult and pediatric populations. Findings on polyethylene glycol-enhanced MR imaging, similar to those of conventional barium studies, may suggest a diagnosis of celiac disease because the technique can not only reveal intestinal involvement but also show extraintestinal findings.

Administration, Oral↗
PubMed2003

MR imaging features of solid pseudopapillary tumor of the pancreas in adult and pediatric patients.

OBJECTIVE: This study was conducted to describe the MR imaging features of solid pseudopapillary tumor of the pancreas. CONCLUSION: Solid pseudopapillary tumor of the pancreas, a tumor typically seen in young women, is a large, well-defined, encapsulated lesion with heterogeneous high or low signal intensity on T1-weighted, heterogeneous high signal intensity on T2-weighted, and early peripheral heterogeneous enhancement with progressive fill-in on gadolinium-enhanced dynamic MR imaging. These features help differentiate this rare tumor from other pancreatic neoplasms.

Adolescent↗
PubMed2003

TRUS staging and follow-up in patients with anal canal cancer.

PURPOSE: The aim of our study was to define the role of grey-scale transrectal ultrasound in the evaluation, staging and follow-up of patients with histologically diagnosed anal canal cancer. MATERIALS AND METHODS: Seventy-six patients underwent digital rectal examination, anoscopy, abdomino-pelvic CT, inguinal and transrectal ultrasound; Fifty-five received combined chemoradiotherapy, whereas 21 received only radiotherapy due to clinical contraindications to chemotherapy. Before and after treatment TNM and UT staging were compared. After treatment we evaluated the sensitivity of transrectal ultrasound in the differentiation of post-radiation fibrosis from residual tumor/local relapse (gold standard: histological analysis). Ultrasound examination was carried out to assess inguinal and perirectal lymph node involvement, and Computed Tomography to detect abdominal lymph nodes. RESULTS: In all stages, except stage 4, there were differences between TNM and UT staging, as TNM is often understaged. After treatment ultrasound showed a sensitivity of 71 percent in the differentiation of fibrosis from residual tumor (the results were confirmed by histopathologic analysis), of 93 percent in the identification of perirectal lymph nodes and of 95 percent in the identification of inguinal lymph nodes. CONCLUSIONS: Transrectal ultrasound is very useful in the staging and follow-up of anal canal carcinoma, in the evaluation of initial tumor volume and reduction after therapy. Ultrasound is useful in the distinction of fibrosis from residual tumor after therapy and as biopsy guidance.

Adult↗
PubMed2002

Contrast-enhanced computed tomographic colonography in the follow-up of colorectal cancer patients: a feasibility study.

The aim of our study was to assess whether contrast-enhanced CT colonography is a feasible alternative to both conventional colonoscopy and liver ultrasonography in the follow-up program of colorectal cancer patients. Thirty-five patients, surgically treated for colorectal cancer, underwent a follow-up program that included physical examination, carcinoembryonic antigen serum assay, conventional colonoscopy, liver ultrasonography, and chest X-ray. For these patients, we added a yearly contrast-enhanced CT colonography. All CT examinations were performed with a high-resolution protocol using a multidetector spiral CT scanner (Siemens, Erlangen, Germany) prior to and after the administration of 130 ml of i.v. contrast material. Images were directly analyzed on a dedicated workstation by two radiologists to determine colonic evaluation, visualization of colonic anastomosis, presence of polyps, and extra-colonic findings. Colonic evaluation was judged as optimal in 91.7% of all colonic segments. All mechanical surgical anastomoses were visualized with CT colonography. There was no evidence of anastomotic recurrence. Seven polyps were detected in five different patients with CT colonography, with two false-positive and no false-negative examinations. Three liver metastases and two basal pulmonary nodules were also identified. Contrast-enhanced CT colonography is a feasible alternative to both conventional colonoscopy and liver ultrasonography in the follow-up of patients operated on for colorectal cancer.

Adenocarcinoma↗
PubMed2002

Feasibility of ultra-low-dose multislice CT colonography for the detection of colorectal lesions: preliminary experience.

Our objective was to evaluate the feasibility of ultra-low-dose scanning for multislice CT colonography in the detection of colorectal lesions. Twenty-seven patients (14 men, 13 women) with clinical indication for conventional colonoscopy were recruited. Multislice spiral CT (Somatom Plus 4 Volume Zoom, Siemens, Germany) examinations were performed after standard oral colonoscopic preparation and colonic distension with room air. Images were acquired using 2.5-mm collimation, 3.0-mm slice thickness, standard reconstruction kernel, 140 kVp, and 10 mAs. Supine and prone acquisitions were obtained in all patients. Images were analyzed on a workstation by two gastrointestinal radiologists. Conventional colonoscopy was performed on the same day in all patients and represented the standard of reference. Total radiation exposure was also calculated. All colorectal cancers were correctly identified at CT colonography (9 of 9, sensitivity 100%). The CT colonography also detected 10 of 12 polyps (overall sensitivity 83.3%). Based on polyp diameter, the sensitivity for the detection of polyps 10 mm or larger was 100% (3 of 3); between 6 and 9 mm, 100% (3 of 3); and 5 mm or smaller, 66.6% (4 of 6). Total radiation exposure for prone and supine acquisitions combined was 1.7 mSv (for men) and 2.3 mSv (for women). Although preliminary, our experience suggests that ultra-low-dose scanning for multislice CT colonography is feasible. This technique provides a sensitivity comparable to that of previous experiences with CT colonography but with a 40-70% reduction of the radiation dose delivered to patients.

Butylscopolammonium Bromide↗
PubMed2002

Experimental colonic phantom for the evaluation of the optimal scanning technique for CT colonography using a multidetector spiral CT equipment.

Our objective was to optimize a scanning protocol for CT colonography using a multidetector scanner with an adaptive-array matrix in a phantom study. A colonic phantom with 27 simulated lesions was examined using a multidetector CT scanner (Somatom Plus 4 Volume Zoom, Siemens, Erlangen, Germany). Three scanning protocols were tested: (a) collimation 1.0 mm, slice thickness 1.0 mm; (b) collimation 2.5 mm, slice thickness 3.0 mm; and (c) collimation 2.5 mm, slice thickness 5.0 mm. Image analysis was performed by two radiologists blinded to the construction of the phantom and to imaging parameters. Sensitivity for lesion detection and image quality was assessed. Computed tomographic colonography detected 27 of 27 lesions with protocol 1 (sensitivity 100%); 26 of 27 lesions with protocol 2 (sensitivity 96.3%); and 23 of 27 lesions with protocol 3 (sensitivity 85.2%). Image quality was graded as optimal for protocol 1, good for protocol 2, and poor for protocol 3. When multidetector CT equipment with an adaptive-array matrix is used, protocols with 1.0- or 3.0-mm slice thickness have a sensitivity for the detection of lesions higher than that obtained with a 5.0-mm slice thickness. Image quality decreases progressively when the slice thickness is increased; therefore, in a clinical setting, we recommend the use of a high-resolution protocol (1.0-mm effective slice thickness) with the highest pitch value in order to reduce scanning time. Dose exposure for such a protocol if combined with 80 mAs is within the range limits recommended by the ICRP for abdominal CT scanning.

Chi-Square Distribution↗
PubMed2002

Pancreatic carcinoma: the role of high-resolution multislice spiral CT in the diagnosis and assessment of resectability.

The purpose of our study was to evaluate multislice computed tomography (MSCT) in the assessment of patients with clinical, laboratory, and US suspicion of pancreatic neoplasm, and to evaluate resectability status. Forty-six patients with a suspected pancreatic tumor underwent MSCT. After a preliminary precontrast survey, a postcontrast scan was performed in the arterial and portal venous phase with the following protocol: 4 x 1-mm collimation; 1.25- and 5-mm slice thickness width, respectively, and 1- and 5-mm reconstruction interval. In all patients pathological correlation was obtained. The evaluation of all images provided a diagnosis in 44 patients, with a sensitivity, specificity, and accuracy of 97, 80, and 96%, respectively. The MSCT correctly provided a diagnosis of unresectability with sensitivity of 96%, specificity of 86%, and accuracy of 93%. Evaluation of 1-mm slices demonstrated 83 of the 91 liver metastases found at surgery; conversely, the 5-mm slices detected only 76 of these lesions. Infiltration of peripancreatic major vessels was demonstrated, and was confirmed at surgery in 18 patients. High-resolution MSCT improves prediction of resectability in patients with suspected pancreatic carcinoma. Parenchymal and vascular information can be achieved with a single MSCT examination.

Adult↗
PubMed2002

Detection of colorectal lesions with virtual computed tomographic colonography.

BACKGROUND: The aim of our study was to compare the performance of virtual computed tomographic colonography with that of conventional colonoscopy in a blinded, prospective study in 165 patients with suspected colorectal lesions. METHODS: There were 165 patients, all referred for conventional colonoscopy, who underwent preliminary virtual computed tomographic colonography. Computed tomograhic images of all suspected lesions were analyzed and subsequently compared with conventional colonoscopy findings. RESULTS: There were 30 colorectal cancers and 37 polyps identified at conventional colonoscopy. Virtual computed tomographic colonography correctly detected all cancers, as well as 11 of 12 polyps of 10 mm in diameter or larger (sensitivity, 92%); 14 of 17 polyps between 6 and 9 mm (sensitivity, 82%); and 4 of 8 polyps of 5 mm or smaller (sensitivity, 50%). The per-patient sensitivity and specificity were 92% and 97%, respectively. CONCLUSIONS: Virtual computed tomographic colonography has a diagnostic sensitivity similar to that of conventional colonoscopy for the detection of colorectal lesions larger than 6 mm in diameter.

Adult↗