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C Bartolozzi

Publications and source records attributed to C Bartolozzi.

At least 55 records · Page 3Linked to original sources
PubMed1999

Endorectal coil MR imaging findings in hemospermia.

The purpose of this study was to illustrate the spectrum of abnormalities found at endorectal coil magnetic resonance (MR) imaging in patients with hemospermia. Ninety patients aged between 23 and 71 years (mean age 41 years) presenting with hemospermia underwent evaluation with endorectal coil MR imaging at 1.5 T. Duration of hemospermia ranged between 5 days and 4 years (mean 15 months). MR examination protocol included T1-weighted spin-echo (SE) and T2-weighted fast SE MR images obtained in the sagittal, coronal, and axial planes. Abnormalities were observed on endorectal-coil MR images in 49 of 90 patients (54%). Blood within the seminal vesicle or the ejaculatory duct was recognized in 23 of 90 patients (25%). Dilatation of the seminal vesicles or the ejaculatory duct was observed in 31 of 90 patients (34%). Cystic lesions were identified in 14 cases, eight of which involved the utriculus and six the ejaculatory duct. Calculi within the seminal vesicles were depicted in seven patients. No malignant disease was demonstrated. In conclusion, despite the evidence that hemospermia is most often a benign and self-limiting condition, we found that endorectal coil MR imaging can detect abnormal findings in more than half of the patients, and may be helpful in assessing the level at which hemorrhage occurred and in defining the cause of the disease.

Adult↗
PubMed1999

Detection of accessory renal arteries with virtual vascular endoscopy of the aorta.

PURPOSE: To evaluate the diagnostic accuracy of virtual vascular endoscopy (VVE) in the detection of accessory renal arteries. METHODS: We retrospectively reviewed the CT angiography data sets of 67 patients (29 male and 38 female; age range 17-72 years, mean age 53 years) imaged for the study of the renal arteries, and affected by renovascular hypertension. All patients also had intraarterial digital subtraction angiography (DSA). CT angiography data sets were processed to obtain maximum intensity projection (MIP) and surface-rendered VVE of the aorta. Axial images, MIP, and VVE were evaluated separately and in combination in the detection of accessory renal arteries. Their results in terms of sensitivity and specificity were then compared with DSA. RESULTS: Axial images had a sensitivity of 88% and specificity of 94% for accessory renal artery detection, MIP had a sensitivity of 88% and specificity of 98%, and VVE had a sensitivity of 63% and a specificity of 88% (p < 0.05 vs DSA), but these increased to 88% and 98% respectively if endoscopic views were integrated with the other display techniques. CONCLUSION: VVE based on surface rendering does not add substantial benefits to CTY angiography; by contrast MIP is the most accurate display technique for the detection of accessory renal arteries.

Adolescent↗
PubMed1999

Pseudoaneurysm of the abdominal aorta: evaluation with virtual angioscopy of spiral-CT data sets.

We describe a case of graft-related pseudoaneurysm of the abdominal aorta evaluated with spiral CT and DSA. Spiral CT data sets were processed to obtain surface-rendered internal views (virtual angioscopy, VA) of the graft and the pseudoaneurysm, and to demonstrate from inside the lumen the site of dehiscence. A jet flow phenomenon inside the pseudoaneurysm was observed at DSA. Spiral-CT axial images, multiplanar volume reconstructions with maximum intensity projections, and shaded surface display showed the site of rupture. The VA findings were: (a) from inside the graft lumen, the evidence of a communication canal between the graft and the pseudoaneurysm; and (b) from inside the pseudoaneurysm, the presence of a jet flow. The VA findings showed good correlation with those obtained with the other imaging techniques.

Aneurysm, False↗
PubMed1999

Abdominal MR: liver and pancreas.

Following the introduction of rapid, high-quality scan techniques and the development of new, tissue-specific contrast agents, the applications of MRI for abdominal imaging are experiencing unprecedented growth. This article examines the current status of liver and pancreatic MRI, highlighting technical and methodological approach, use of contrast agents, and main clinical applications. The MRI technique appears to be the ideal diagnostic tool for detection and characterization of benign and malignant liver neoplasms, and for evaluating tumor response after nonsurgical treatments. Dynamic imaging after bolus injection of a gadolinium chelate is currently a fundamental component of an MRI examination of the liver in many instances. Optimal dynamic scanning depends on the use of a multisection spoiled gradient-echo technique that allows one to image the entire region of interest during a single suspended respiration. Images are obtained during four phases relative to the injection of the contrast agent: precontrast, arterial (pre-sinusoidal), portal (sinusoidal), and delayed (extracellular) phase. Liver-specific contrast agents, including hepatobiliary agents and reticuloendothelial system-targeted iron oxide particles, however, may offer advantages over gadolinium chelates in some clinical settings. Computed tomography is still preferred to MRI for imaging the pancreas. However, state-of-the-art MRI may currently be at least as accurate as spiral CT for depiction of inflammatory and neoplastic pancreatic diseases. Moreover, MRI has the advantage of allowing simultaneous investigation of the biliary tree, owing to cholangiopancreatography techniques. Hence, a comprehensive assessment of most pancreatic diseases can be achieved with a single examination.

Contrast Media↗
PubMed1999

MR virtual endoscopy of the pancreaticobiliary tract.

PURPOSE: To evaluate the feasibility of surface-rendered magnetic resonance virtual endoscopy (MRVE) of magnetic resonance cholangiopancreatography (MRCP) data sets. We retrospectively reviewed MR cholangiopancreatography data sets of 120 patients with biliary stone (n=40), inflammatory ampullary stenosis (n=12), pancreatic tumor (n=8), cholangiocarcinoma (n=7), stenosis of surgical bilio-enteric anastomosis (n=4), extrinsic localized common bile duct stenosis (n=2), ampullary carcinoma (n=2), pancreatic duct stone (n=1), tumor of the gallbladder (n=1), and normal pancreaticobiliary tree (n=43). MRVE views were generated with Navigator software. Segmentation of the acquired data sets was performed with a thresholding technique. Navigation sequences were simulated through the entire biliary tract. MRVE was obtained in 27 (63%) of the 43 normal patients. Endoscopic views were generated in all 77 patients with partial or complete obstruction of the pancreaticobiliary tree. Among these, three groups of patterns were identified: 36 (47%) endoluminal masses (polyp-like masses), 17 (22%) luminal stenoses, 24 (31%) luminal occlusion. In 29 cases, hole artifacts through the internal wall were observed and interpreted as mistakes of segmentation. MRVE proved to show the internal anatomy of the biliary tract and endoluminal changes due to pathological condition. Further investigations are needed to test the usefulness and the potentialities of this technique.

Adolescent↗
PubMed1999

Choledocolithiasis: diagnostic accuracy of MR cholangiopancreatography. Three-year experience.

The purpose of this study was to evaluate the diagnostic accuracy of MR cholangiopancreatography (MRCP) in the detection of common bile duct stones. A series of 286 consecutive patients were referred for MRCP, that was performed with a 1.5 T MR unit, through a non-breath-hold, respiratory-triggered, fat-suppressed, two-dimensional, heavily T2-weighted fast spin-echo sequence in the coronal plane. Axial T1 and T2-weighted sequences were first obtained. Axial, coronal, and Maximum Intensity Projection images were evaluated by three independent readers, who were asked to determine whether stones were present or not inside the biliary tract. The findings of MRCP images were compared with endoscopic retrograde cholangiopancreatography, percutaneous trans-hepatic cholangiography, intra-operative cholangiography, surgical, or imaging follow-up findings. Two-hundred and seventy-eight out of 286 MRCP examinations were judged diagnostic by the three reviewers. Among the 278 patients included in our study group, biliary tract lithiasis was proved in 76 cases (27%). On the basis of reviewers' reading, MRCP had sensitivity 92-93%, specificity 97-98%, positive predictive value 91-93%, negative predictive value 97-98%, and the diagnostic accuracy ranged between 95% and 96% in the detection of calculi. Interobserver agreement was excellent (K = 0.84, kappa statistic). MRCP showed a high diagnostic accuracy and an excellent inter-observer agreement in the detection of common bile duct stones.

Adolescent↗
PubMed1999

Noninvasive assessment of renal artery stenosis: current imaging protocols and future directions in ultrasonography.

Doppler ultrasound is one of many modalities that have been evaluated for the detection of renal artery stenosis. The lack of standardization in examination protocols and diagnostic criteria, as well as the wide differences in reported accuracy among different laboratories have, however, prevented universal acceptance of this technique as a reliable screening test for renal artery stenosis. The recent introduction of ultrasound contrast agents has substantially expanded the potential of color Doppler ultrasound. The use of microbubble echoenhancers in combination with harmonic Doppler imaging has been shown to improve diagnostic confidence by improving the operator's ability to visualize the renal arteries, and to significantly reduce the number of equivocal examinations. Moreover, contrast-enhanced Doppler ultrasound can provide functional information through analysis of renal time-intensity wash in/wash out curves. State-of-the-art contrast-enhanced Doppler ultrasound seems to have the potential to become a useful screening test for patients at risk from renovascular hypertension.

Blood Flow Velocity↗
PubMed1999

Virtual CT intravascular endoscopy of the aorta: pierced surface and floating shape thresholding artifacts.

Two types of artifacts may appear in virtual computed tomographic endoscopic views of the aorta rendered at different threshold levels: pierced surface and floating shape artifacts. A positive correlation was found between mean attenuation of the aorta and the threshold levels at which these artifacts appeared. The correlation was statistically significant (0.71 < or = r < or = 0.86) for floating shape. An artifact-free threshold range can be predicted on the basis of aortic enhancement.

Adult↗
PubMed1999

MultiHance: help or hype?

MultiHance (Gd-BOPTA) couples specific, long lasting enhancement of magnetic resonance signal intensity in the liver parenchyma with the plasma kinetics of agents targeted to the extracellular fluid space. Therefore, this new contrast agent may be used both as an extracellular fluid agent, such as Magnevist (Gd-DTPA) or ProHance (gadoteridol) or as a liver-specific agent, such as Teslascan (mangafodipir) or iron oxides (e.g., Endorem). The clinical studies conducted so far have shown that MultiHance improves liver cancer detection by magnetic resonance imaging, the characterization of liver lesions, when used in combination with bolus dynamic magnetic resonance imaging, and the diagnostic performance of magnetic resonance imaging in extra-hepatic organ areas, such as brain and spine and the cardiovascular system. This brief article attempts to define the potential utility of this novel agent in the daily clinical setting, taking into account what is already available in radiology departments. It summarizes briefly the clinical need for a magnetic resonance contrast agent which improves the impact of magnetic resonance imaging for both the detection and characterization of focal liver lesions and concludes with the affirmation that MultiHance would be a definite help to radiologists working on all aspects of magnetic resonance imaging.

Carcinoma, Hepatocellular↗
PubMed1998

Proton magnetic resonance spectroscopy in an Italian family with spinocerebellar ataxia type 1.

Linkage and DNA analysis, magnetic resonance (MR) imaging, and single-voxel proton MR spectroscopy were obtained in 10 members of an Italian kindred with spinocerebellar ataxia type 1 (SCA1). The size of the basis pontis, cerebellar hemispheres, middle cerebellar peduncles, and medulla oblongata were decreased in 4 members carrying the SCA1 gene, compared with 6 unaffected subjects. Diffuse signal changes in the pons and cerebellum were observed only in the carrier with the longest disease duration and greatest disability. The N-acetylaspartate/creatine ratio and the choline/creatine ratio in the basis pontis were markedly decreased in 2 symptomatic SCA1 carriers and moderately decreased in 2 asymptomatic SCA1 carriers, compared with the unaffected family members and a control group of 10 healthy volunteers. Minor decreases in the N-acetylaspartate/creatine ratio and the normal choline/creatine ratio were observed in the cerebellar hemisphere of the SCA1 carriers. Reduction of the N-acetylaspartate/creatine ratio, demonstrated by MR spectroscopy in the pons, is likely to reflect a loss of neuronal viability and might represent a biochemical marker of SCA1 more sensitive than brainstem and cerebellum atrophy and signal changes shown by MR imaging.

Adult↗
PubMed1998

Detection of colorectal liver metastases: prospective comparison of unenhanced and ferumoxides-enhanced magnetic resonance imaging at 1.5 T, dual-phase spiral CT, and spiral CT during arterial portography.

The purpose of this study was to compare the efficacy of unenhanced and ferumoxides-enhanced magnetic resonance imaging with that of dual-phase spiral CT and spiral CT during arterial portography (CTAP) for the detection of colorectal liver metastases. Fourteen patients with liver metastases candidates for partial hepatectomy were examined with dual-phase spiral CT, unenhanced and ferumoxides-enhanced MR imaging at 1.5 T, and spiral CTAP. Imaging tests were read blinded, prospectively, quantitating number of lesions excepting CTAP which used US to exclude cysts. Subsequent intraoperative US and pathologic findings were correlated with preoperative imaging results. At surgery, 36 lesions 0.5-13 cm in diameter (mean+/-standard deviation, 2.9+/-2.1 cm) were identified. Dual-phase spiral CT depicted 21/36 (58%); precontrast MR imaging, 19/36 (53%); ferumoxides-enhanced MR imaging, 30/36 (83%); and spiral CTAP, 34/36 (94%) lesions. Ferumoxides-enhanced MR imaging was significantly more sensitive than spiral CT and unenhanced MR imaging (P < 0.01). The difference in sensitivity between ferumoxides-enhanced MR imaging and spiral CTAP was not statistically significant (P> 0.1). Spiral CTAP, however, depicted nine false-positive lesions (2 hemangiomas, 7 perfusion defects). The positive predictive value was 79% for spiral CTAP and 100% for combined pre- and postcontrast MR imaging. We conclude that ferumoxides-enhanced MR imaging is superior to unenhanced MR imaging and biphasic spiral CT for depiction of colorectal liver metastases. Further investigation is needed to clarify whether MR imaging with use of ferumoxides might replace spiral CTAP for preoperative evaluation of liver resection candidates.

Adult↗
PubMed1998

Combined transcatheter arterial chemoembolization and percutaneous ethanol injection for the treatment of large hepatocellular carcinoma: local therapeutic effect and long-term survival rate.

The aim of our study was to investigate local therapeutic effects and long-term results of combined transcatheter arterial chemoembolization (TACE) and percutaneous ethanol injection (PEI) in the treatment of large hepatocellular carcinoma (HCC). Eight-six patients (67 males and 19 females, age range 48-75 years, mean age 65.1 years) with Child-Pugh class A (n = 48) or B (n = 38) liver cirrhosis and a large HCC (main tumor 3.1-8 cm in diameter with no more than two daughter nodules) were enrolled in a prospective study. All patients underwent a single TACE session followed by PEI. Follow-up ranged from 4 to 65 months (mean 27.8 months, median 26 months). No major complication occurred. The local therapeutic effect, as assessed on the basis of findings at CT and MR imaging, was complete response in 71 of 86 patients (82 %) and partial response in 15 of 86. Overall survival rates by the Kaplan-Meier method were 92 % at 1 year, 83 % at 2 years, 69 % at 3 years, 58 % at 4 years, and 47 % at 5 years. Survival of Child-Pugh A patients (75 % at 3 years and 59 % at 5 years) was significantly longer (p < 0.01) than that of Child-Pugh B patients (61 % at 3 years and 35 % at 5 years). Combined TACE and PEI is an effective treatment for large HCC.

Actuarial Analysis↗
PubMed1998

CT in vascular pathologies.

Since the introduction of helical scanners, CT angiography (CTA) has achieved an essential role in many vascular applications that were previously managed with conventional angiography. The performance of CTA is based on the accurate selection of collimation width, pitch, reconstruction spacing and scan delay, which must be modulated on the basis of the clinical issue. However, the major improvement of CT has been provided by the recent implementation of many post-processing techniques, such as multiplanar reformatting, shaded surface display, maximum intensity projections, 3D perspectives of surface and volume rendering, which simulate virtual intravascular endoscopy. The integration of the potentialities of the scanner and of the image processing techniques permitted improvement of: (a) the evaluation of aneurysms, dissection and vascular anomalies involving the thoracic aorta; (b) carotid artery stenosis; (c) aneurysms of abdominal aorta; (d) renal artery stenosis; (e) follow-up of renal artery stenting; and (f) acute or chronic pulmonary embolism. Our experience has shown that the assessment of arterial pathologies with CTA requires the integration of 3D post-processing techniques in most applications.

Angiography↗
PubMed1998

Radio-frequency thermal ablation of liver metastases with a cooled-tip electrode needle: results of a pilot clinical trial.

The aim of this study was to evaluate feasibility, safety, and effectiveness of radio-frequency (RF) thermal ablation, performed by using a cooled-tip electrode needle, in the treatment of liver metastases. Twenty-nine patients (20 males and 9 females; age range 43-77 years) with one to four hepatic metastases 1.1-4.8 cm in diameter (mean 2.9 +/- 0.8 cm) from previously resected intra-abdominal primary malignancies were treated. All patients were excluded from surgery and had partial or no response to chemotherapy. Radio-frequency ablation was performed by using a 100-W generator and 17-gauge, dual-lumen, cooled-tip electrode needles with a 2- to 3-cm exposed tip. Exposure time was 12 min for each needle insertion. Findings at spiral CT were used to assess the therapeutic response. A total of 127 insertions were performed (mean 2.4 +/- 1.7 insertions/lesion) during 84 treatment sessions (mean 1.6 +/- 0.7 sessions/lesion) in absence of major complications. Complete tumor response (i. e., unenhancing area of thermal necrosis larger than the treated tumor) was seen in 41 (77 %) of 53 lesions, including 33 (87 %) of 38 lesions 3 cm or less in diameter. After a mean follow-up period of 6.5 +/- 2.1 months (range 3-9 months), recurrence of the treated lesion was seen in 5 (12 %) of the 41 cases. New metastatic lesions appeared in 7 patients. Two patients died after 6 and 8 months, respectively. Of the 27 patients still in follow-up, 14 are currently free of disease. Radio-frequency thermal ablation with a cooled-tip electrode needle is a safe and effective local treatment for hepatic metastases 3 cm or less in greatest dimension.

Adult↗
PubMed1998

Interactive DICOM image transmission and telediagnosis over the European ATM network.

The European High-Performance Information Infrastructure in Medicine, n(o)B3014 (HIM3) project of the Trans-European Network--Integrated Broadband Communications (TEN-IBC) program, started on March 1996 and finished on February 1997, aimed to test the medical usability of the European asynchronous transfer mode (ATM) network in medical image transmission. The Department of Radiology, University of Pisa, Pisa, Italy, and St-Luc University Hospital, Brussels, Belgium, involved in the project as healthcare partners in the radiological domain, established several connection sessions finalized to test the usability of Digital Imaging and Communication (DICOM) image transmission and interactive telediagnosis tools in the daily radiological practice. The Pisa site was connected to the Italian ATM pilot (Sirius Network) through the Tuscany metropolitan area network (MAN), while St-Luc University Hospital was connected to Belgium ATM network through the Brussels MAN. By means of international connections provided by the European JAMES project, a link between the two sites was established, connecting both national ATM networks. Due to the large variety of hardware present in the medical centers, multiplatform software tools were used and tested: central test node (CTN) release 2.8 [3], VAT [6], NV-3.3 [7], and IDI (UCL homemade multiplatform teleradiology tool for interactive visualization and processing of DICOM images). During the telediagnosis session, lead by radiologists in both hospitals, each site submitted neuroradiological clinical cases to the other for remote consultation. The connection, available for a period of two weeks, at 2-Mbit/s bandwidth, allowed the transmission of MR images (256 x 256 x 12 bit) and simultaneous multimedia interactive discussion of the cases. Both off-line transmission and review of the images, using the CTN DICOM transfer routines, and on-line interactive image discussion, using the IDI telediagnosis software, were tested successfully from the technical and medical point of view.

Computer Communication Networks↗
PubMed1998

Hepatocellular carcinoma treatment with percutaneous ethanol injection: evaluation with contrast-enhanced color Doppler US.

PURPOSE: To investigate the ability of contrast agent-enhanced color Doppler ultrasonography (US) in evaluating the response of hepatocellular carcinoma (HCC) to percutaneous ethanol injection (PEI). MATERIALS AND METHODS: Forty-two patients (36 men, six women; age range, 51-79 years) with 54 1.3-7.0-cm-diameter (mean +/- SD, 2.8 cm +/- 1.1) HCC lesions were examined with contrast-enhanced color Doppler US before and after PEI. Spiral computed tomography (CT) and percutaneous biopsy also were performed to establish the outcome of therapy. RESULTS: Before PEI, intratumoral color signals were demonstrated at contrast-enhanced color Doppler US in 47 (87%) lesions (in 40 patients). After PEI, blood flow signals were no longer detected in all 34 of the lesions that were found to be necrotic at spiral CT and biopsy. In 12 (92%) of 13 lesions containing residual viable tumor, intratumoral color signals corresponding to the enhancing areas at spiral CT were still identified at contrast-enhanced color Doppler US. These 12 lesions were retreated with PEI by targeting the areas of residual tumor with contrast-enhanced color Doppler US guidance. Complete necrosis was seen after the second PEI cycle in nine of 12 lesions. CONCLUSION: Contrast-enhanced color Doppler US shows promise in assessing the therapeutic effect of PEI on HCC and in guiding additional treatment in cases of incomplete response.

Aged↗
PubMed1998

[Anterolateral fibrous impingement of the ankle. Report of 14 cases].

PURPOSE: Anterolateral fibrous impingement of the ankle is one of the causes of post-traumatic pain in the foot. We investigated the comparative accuracy of US and MRI in this condition. MATERIAL AND METHODS: Fourteen patients were submitted to arthroscopy, plain radiography, US and MRI of the foot. The patients, all sportsmen, had a clinical history of sprains; the major symptoms were pain, swelling and clicking on foot dorsiflexion. RESULTS: US showed anterior talofibular ligament changes in all patients and mid-low-echogenicity synovial tissue filling the lateral malleolar gutter. MRI demonstrated a small mass of synovial tissue in the gutter in 8 patients, with mid-low signal intensity before Gd-DTPA and mid-low contrast enhancement after contrast administration and no abnormal findings in 6 patients. Arthroscopy showed a small firm mass of proliferative synovium in the lateral malleolar gutter in all patients. CONCLUSIONS: Fibrous impingement must be suspected in the sportsmen presenting typical symptoms after ankle trauma. US is poorly accurate in diagnosing this condition. MRI shows a small synovial mass in the lateral malleolar gutter in more than half the patients, but aspecific MR findings do not rule impingement our MR images must be acquired along the proper planes and with Gd-DTPA administration.

Adult↗