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C Bartolozzi

Publications and source records attributed to C Bartolozzi.

At least 55 records · Page 3Linked to original sources
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↗
PubMed1997

Prediction of pathological tumor volume in clinically localized prostate cancer: value of endorectal coil magnetic resonance imaging.

The purpose of this study was to determine whether endorectal coil magnetic resonance imaging (MRI) enables accurate assessment of pathologic tumor volume in patients with clinically localized prostate carcinoma. Twenty-four patients with biopsy-proved prostate carcinoma underwent MRI at 0.5 T before radical prostatectomy. Tumor volumes were determined independently on axial fast-spin-echo (SE) T2-weighted MR images and whole-mount pathology slides of the surgical specimens. At pathology, tumor volumes ranged from 0.17 to 9.42 cm3 (mean +/- SD, 3.11 +/- 2.99 cm3). A strong correlation (r = .944) was found between measurements of tumor volume based on MR images and pathological specimens. The error was less than 0.5 cm3 in 14 cases, in the range of 0.5-1 cm3 in 7 cases, and more than 1 cm3 in 3 cases. By using an MR tumor volume of 2 cm3 as cutoff value, extracapsular tumor spread could be predicted with a sensitivity of 81.2%, a specificity of 100%, and an accuracy of 87.5%. Tumor volume determinations based on MR images seem to be accurate enough to be helpful in clinical decision-making.

Humans↗
PubMed1997

Spontaneous epidural emphysema and pneumomediastinum during an asthmatic attack in a child.

CT revealed the presence of epidural emphysema as an incidental finding in a 13-year-old boy in whom mild infrequent coughing during an asthmatic attack resulted in a pneumomediastinum and subcutaneous emphysema. Epidural emphysema was not associated with neurological symptoms. The CT images demonstrated the pathway of air leakage from the posterior mediastinum through the intervertebral foramina into the epidural space. Repeat CT showed spontaneous resolution of the epidural emphysema.

Adolescent↗
PubMed1997

Usefulness of echo-color Doppler in differentiating parathyroid lesions from other cervical masses.

The aim of our study was to clarify possible differential color Doppler US features between parathyroid lesions and other cervical masses. A total of 56 parathyroid lesions in 54 patients with primary hyperparathyroidism were preoperatively examined with color Doppler sonography. Color Doppler flow patterns were compared with those of 72 thyroid nodules and 20 cervical lymph nodes. In 38 parathyroid lesions a correlation between color Doppler patterns and size, location, and pathological findings was performed. Color Doppler sonography showed five vascular distribution patterns: pattern I, absence of flow; pattern II, focal peripheral flow ("vascular pole") with arterial Doppler spectrum; pattern III, peripheral flow; pattern IV, internal flow ("parenchymal pattern"); pattern V, peripheral and intranodular flow. Pattern I was not specific for any cervical lesion considered. Conversely, pattern IV was observed solely in parathyroid lesions, and pattern II was observed in only one nonparathyroid lesion (thyroid nodule). Mixed pattern (pattern V) was observed solely in thyroid nodules. In addition, pattern III was a characteristic finding of thyroid nodules and was observed in only one parathyroid lesion. Color Doppler patterns of the parathyroid masses did not correlate with the size of the lesion or pathological findings, but only with the location of the gland. Our study showed that color Doppler assessment of parathyroid lesions is a useful integration of gray-scale US and may be helpful in distinguishing parathyroid lesions from other cervical masses.

Adenoma↗
PubMed1997

Long-term results of percutaneous ethanol injection therapy for hepatocellular carcinoma in cirrhosis: a European experience.

The objective of our work was to evaluate the long-term results of percutaneous ethanol injection (PEI) for the treatment of hepatocellular carcinoma (HCC) in patients with liver cirrhosis. A total of 184 cirrhotic patients with HCC underwent PEI as the only anticancer treatment over an 8-year period. Patients were followed after therapy by means of clinical examinations, laboratory tests, and US and CT studies performed at regular time intervals. Survival rates were determined according to the Kaplan-Meier method. The overall survival was 67% at 3 years, 41% at 5 years, and 19% at 7 years. The 3-, 5-, and 7-year survival rates of patients with single HCC < or = 3 cm (78, 54, and 28%, respectively) were significantly higher (p < 0.01) than those of patients with single HCC of 3.1-5 cm (61, 32, and 16, respectively) or multiple HCCs (51, 21, and 0%, respectively). Survival of Child-Pugh A patients (79% at 3 years, 53% at 5 years, and 32% at 7 years) was significantly longer (p < 0.01) than that of Child-Pugh B patients (50% at 3 years, 28% at 5 years, and 8% at 7 years). A selected group of 70 patients with Child-Pugh A cirrhosis and single HCC < or = 3 cm had a 7-year survival of 42%. Long-term survival of cirrhotic patients with HCC treated with PEI is comparable to that reported in published series of matched patients submitted to surgical resection.

Adult↗
PubMed1997

Comparison of the diagnostic performance of high-frequency ultrasound as a first- or second-line diagnostic tool in non-palpable lesions of the breast.

To compare the diagnostic performance of high-frequency ultrasound (HFU) as a first- or second-line diagnostic tool in non-palpable lesions (NPL) of the breast and to define the place of HFU in the diagnostic process, 89 women with this kind of lesion, previously detected by mammography, underwent HFU with 7.5-13 MHz transducers. The examinations were performed by two equally experienced operators of which only one (operator I) was aware of the mammographic findings. The mammographic examinations revealed the following non-palpable lesions: asymmetry-hyperdensity (17 cases), nodule (44 cases), stellate lesion (5 cases), microcalcifications (23 cases). Total sensitivity of HFU in the examinations performed by operator I was 83 %, while in the examinations performed by operator II (unaware of the mammographic findings) it was only 35 %. In all cases HFU allowed the operators to determine the basic features of the lesions. Our experience confirms that ultrasonography, even if performed with high frequency, cannot be proposed as a screening examination but may profitably be employed as a second-step technique to characterize NPL previously identified by mammography. This 'second-step' role can do the following: rule out true pathology (cases of false-positive mammography findings); furnish some basic features in the case of focal lesions; show other findings in the case of microcalcifications, such as microcysts, 'filled duct' appearance, parenchymal inhomogeneities and nodules; guide interventional procedures; and localize lesions preoperatively.

Breast Neoplasms↗
PubMed1997

Differentiation of hepatocellular adenoma and focal nodular hyperplasia of the liver: comparison of power Doppler imaging and conventional color Doppler sonography.

The aim of our study was to compare the diagnostic efficacy of power Doppler imaging and conventional color Doppler sonography for differentiating between hepatocellular adenoma (HCA) and focal nodular hyperplasia (FNH) of the liver. Thirty-one focal liver lesions (in 29 patients) with histologic proof of HCA (n = 9) or FNH (n = 22) were studied with power and color Doppler sonography according to a standardized examination protocol. The size of the lesions ranged between 1.5 and 14.5 cm (HCA, 3.5-14.5 cm, mean +/- SD 7.3 +/- 3.3 cm; FNH, 1.5-9.1 cm, mean +/- SD 5.1 +/- 2.1 cm). Intratumoral vessels with a venous Doppler spectrum, associated with either pulsatile or continuous peripheral flow, were detected in HCA (eight of nine lesions by power Doppler imaging and six of nine by color Doppler imaging) but not in FNH. In contrast, color signals with an arterial Doppler spectrum, radiating from the center to the periphery of the lesion, were depicted in FNH (20 of 22 cases by power Doppler imaging and 15 of 22 by color Doppler sonography) but not in HCA. Differentiation of HCA and FNH was achieved in 28 of 31 cases (90 %) by power Doppler imaging and in 21 of 31 (68 %) by color Doppler sonography (p < 0.01). Power Doppler imaging is superior to conventional color Doppler sonography in the depiction of the intratumoral flow characteristics of HCA and FNH, and enables a more accurate differential diagnosis than color Doppler sonography.

Adenoma, Liver Cell↗