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N Villari

Publications and source records attributed to N Villari.

70 records · Page 4Linked to original sources

Solitary necrotic nodule of the liver: imaging and correlation with pathologic features.

We describe two cases of solitary necrotic nodule of the liver, an uncommon nonmalignant lesion that can mimic a metastasis. The nodule appeared hypoechoic, or targetlike, on sonography, hypodense without contrast enhancement on computed tomography, and hypointense on magnetic resonance imaging, including diffusion-weighted images. These features, peculiar when considered together, are explained by the coagulative type of necrosis.

Adult↗

Contrast-enhanced time-resolved MR angiography of spinal vascular malformations.

PURPOSE: The purpose of this work was to assess the potential and limitations of a contrast-enhanced time-resolved MR angiography technique for evaluation of spinal vascular malformations. METHOD: Two patients with intramedullary arteriovenous (AV) malformations and three patients with dural AV fistula underwent four serial acquisitions, every 17-20 s, of 20-32 coronal 1.5- to 2-mm-thick partitions with a fast 3D SPGR sequence after injection of 0.2-0.3 mmol/kg paramagnetic contrast agent. This was followed by coronal 3D and sagittal or coronal 2D phase contrast (PC) MR angiography. RESULTS: No spinal vessels were visualized in the first (baseline) series. In patients with intramedullary AV malformations, the arterial feeders, nidus, and perimedullary draining veins were visualized in the second (early) series. In the third (intermediate) series, the arterial feeder vanished, whereas the intercostal and lumbar veins appeared. In patients with dural AV fistula, abnormal intraspinal vessel appeared in the third series and persisted, although less conspicuous, in the fourth (late) series. Contrast-enhanced time-resolved MR angiography demonstrated the venous components of the lesion with better conspicuity than 3D PC MR angiography, whereas it was inferior for visualization of arterial feeders. Moreover, indirect identification of the level of the dural AV fistula was possible only on the phase display of the 2D PC MR angiography. CONCLUSION: Contrast-enhanced time-resolved MR angiography is a useful complement to PC MR angiography for the evaluation of spinal vascular malformation.

Arteriovenous Fistula↗

Value of hepatic arterial phase CT versus lipiodol ultrafluid CT in the detection of hepatocellular carcinoma.

OBJECTIVE: To evaluate the role of hepatic arterial phase (HAP) spiral computed tomography (CT), as compared with iodized oil (Lipiodol ultrafluid [LUF]) CT for revealing nodular hepatocellular carcinomas (HCC). METHODS: Twenty-four cirrhotic patients underwent two-phase HCT examination: HAP 25 seconds and portal phase 70 seconds after injection of 1.5 mL/Kg contrast medium. All patients also underwent hepatic angiography and intraarterial infusion of iodized oil; LUF CT was performed 3-4 weeks after infusion. HCT images were compared with LUF CT images for detection of hepatic nodules. RESULTS: We found no significant difference between the sensitivity of HAP CT and LUF CT for nodules >10 mm, while HAP CT was more sensitive than LUF CT in revealing nodules <10 mm (47 vs. 27, p < 0.001). CONCLUSIONS: HCT should be considered as the first method for the detection of HCC, whereas LUF CT should be used only for therapy.

Aged↗

The role of lymphography in the staging and treatment of ovarian dysgerminoma. Report on 27 cases.

In 1960-1985, 35 patients with ovarian dysgerminoma were referred after surgery to the Radiation Therapy Unit of the University of Florence. Twenty-seven of these cases were analysed with regard to lymphangiography findings before radiation therapy. Nodes were judged as positive in 18 of the 27 cases (44%) and in all the positive cases the paraaortic nodes were involved. The relevance of lymphography in the staging and follow-up of patients with ovarian dysgerminoma is discussed.

Adolescent↗

[High resolution and spirometric synchronization computerized tomography in chronic obstructive bronchopneumopathy].

PURPOSE: To assess the feasibility of spirometrically gated HRCT in patients with chronic obstructive pulmonary disease and to correlate the density measures with the results of pulmonary function tests. MATERIAL AND METHODS: Pulmonary function tests and spirometrically gated HRCT were performed, on the same day, in 20 patients with chronic obstructive pulmonary disease. Spirometrically gated HRCT scans at 90 and 10% of the patient's vital capacity were acquired, at three anatomical levels (carena, carena plus 5 cm, carena minus 5 cm). In each section, lung parenchyma was isolated from the other thoracic structures and from the main bronchi and a densitometric evaluation was applied to the regions of interest. A histogram showing the distribution of the pixel frequencies versus lung densities, the mean CT number and the pixel index at -910 HU (for scans acquired at 10% of the patient's vital capacity) and at -950 HU (for scans obtained at 90% of the patient's vital capacity) were obtained. Average acquisition time for the spirometrically gated HRCt was 15-20 minutes, average data processing time was 20 minutes. RESULTS: The mean CT number and the pixel index at -910 HU obtained at 10% of the patient's vital capacity correlated with the Tiffeneau index (r = 0.85; R = 0.78 respectively). The pixel index at -910 HU correlated also with the ratio of residual volume to total lung capacity (r = 0.65). The mean CT number and the pixel index obtained at 90% of the vital capacity correlated with the lung diffusion of carbon monoxide (r = 0.64 and r = 0.79 respectively). CONCLUSIONS: In our study, we found good correlation between the densitometric values obtained with spirometrically gated HRCT and the respiratory function tests routinely employed to assess the presence and the gravity of obstructive pulmonary disease. A good reproducibility of the data is guaranteed by the spirometical gating which enables standardization of the lung acquisition volume, and by the semiautomatic contour tracing program combined with an automated densitometric evaluation. The main disadvantages of the technique are the relatively long acquisition and evaluation times. Spirometrically gated HRCT densitometry is a promising tool for longitudinal studies of diffuse lung disease (pulmonary emphysema and fibrosis).

Adult↗

Transient hepatic attenuation differences (THAD) not connected to focal lesions.

PURPOSE: To report our experience with helical CT evaluation of transient hepatic attenuation differences (THAD), and in particular of those not associated with focal lesions, in an attempt to provide an aetiopathogenetic picture that accounts for the morphology, evolution and density of THAD. MATERIALS AND METHODS: Between January 1998 and January 2001 we observed THAD in 130/988 biphasic helical CT liver examinations performed in the arterial and portal dominant phase. THAD were associated to focal hepatic lesions in 87 patients; in 43 patients there was no such association. This second group of patients, composed of 23 males and 20 females ranging in age from 17 to 80 years (average = 58.8), was enrolled in the study. THAD were associated to: Budd-Chiari syndrome (9), portal venous thrombosis (10), liver cirrhosis (7), acute inflammation of an adjacent organ (4), dilatation of the entire biliary tree (3), hepatic stasis caused by heart failure (2) and constrictive pericarditis (1), fine-needle percutaneous biopsy (2), arterioportal shunting (2), parenchymal compression by fractured ribs (2) and by a strengthened phrenic pillar (1). THAD were evaluated according to extension, morphology and density. For each case at least 10 density measurements were performed by sampling regions of interest on the parenchyma with THAD and on the contralateral parenchyma. The results (mean and standard deviation) were compared to those relative to 30 healthy patients. 22/43 patients were followed up for 6#150;24 months by at least one US and helical CT examination. During CT, the direct appreciation of vascular thrombus during the portal dominant phase was also considered. RESULTS: We detected 18 localised and 25 diffuse THAD. The localised sectoral THAD (11), wedge-shaped with clear border sign, were associated to thrombosis of a portal branch (6), fine-needle percutaneous biopsy (2), arterioportal shunting (2) and partial Budd-Chiari syndrome (1). The localised non-sectoral THAD (7), with variable morphology and without the clear border sign, were associated to acute inflammation of an adjacent organ (4) and to parenchymal compression by the ribs or diaphragm (3). Diffuse THAD associated to Budd-Chiari syndrome (8) and to heart failure (3) showed mosaic enhancement of hepatic parenchyma (patchy pattern); those linked to portal trunk thrombosis (4) and cirrhosis (7) revealed predominant enhancement of external hepatic parenchyma (central-peripheral phenomenon); finally, those concurrent with dilatation of the entire biliary tree showed parenchymal enhancement close to the dilated bile ducts (peribiliary pattern). Follow-up (22/43) demonstrated complete THAD regression after removal (5/22) and less conspicuity of THAD after partial overcome of the stoppage (1/22). In 2/22 cases of arterioportal shunting no substantial changes were seen. The remaining 14/22 cases showed a gradual, slow tendency towards THAD regression with hypotrophy of the involved parenchyma and compensatory contralateral hypertrophy even in the case of endurance of the causative agents. CONCLUSIONS: Based on our experience and the literature we suggest a classification for THAD unrelated to focal hepatic lesions. We recognise 4 causes: portal vein stoppage-obstruction, portal in-flow diversion, trauma and inflammation. When THAD is related to the first three causes pathogenesis is portal hypoperfusion. In the fourth group the mediators of the arterial phenomena are those of inflammation even though portal hypoperfusion might be involved as well. THAD identification makes the detection of vascular thrombi easier by comparison with their direct finding during the portal dominant phase. Finally, THAD are to be investigated for their potential utility in the detection and characterisation of several hepatic diseases. As a consequence, hepatic CT studies cannot ignore arterial dominant phase evaluation, even if no focal hepatic lesions are expected.

Adolescent↗

Screening of lung cancer with low dose spiral CT: results of a three year pilot study and design of the randomised controlled trial ''Italung-CT''.

PURPOSE: To report the results of a three-year observational pilot study of lung cancer screening with low dose computed tomography (CT) and to present the study design of a randomised clinical trial named as ''Italung-CT''. MATERIALS AND METHODS: Sixty (47 males and 13 females, mean age 64+/-4.5 years) heavy smokers (at least 20 packs-year) underwent three low-dose spiral CT screening tests one year apart on a single slice or multislice CT scanner. Indeterminate nodules were managed according to the recommendations of the Early Lung Cancer Action Project. RESULTS: and Indeterminate nodules were observed in 33 (55%) of the subjects (60% at the baseline screening test, 24% at the first annual test and 16% at the second annual test). The size of the largest indeterminate nodule was <5 mm in diameter in 20 subjects, 10 of whom showed the nodule at the baseline test. Forty-five subjects (75%) completed the first annual test and 42 (70%) the second annual test. One (1.6%) prevalent lung cancer (adenosquamous carcinoma) and one (2.2%) incident lung cancer (small cell cancer at the first annual examination) were observed, as well as a pulmonary localisation of Hodgkin's lymphoma (at the second annual test). In addition, one subject underwent lung surgery for a chondromatous hamartoma. CONCLUSIONS: The results of the pilot study are substantially in line with those of other observational studies of greater sample size. This justifies optimism about the reliability of the results in the screened arm of the ''Italung CT'' trial which has just begun.

Female↗

Magnetic resonance (MR) evaluation of bone marrow in vertebral bodies.

Magnetic Resonance (MR) imaging was used to examine the hematopoietic bone marrow in the vertebral bodies of eight healthy subjects, and of 35 cancer patients who had been previously treated with radiation therapy. MR was instrumental in distinguishing viable hematopoietic tissue (red marrow) from adipose tissue (yellow marrow), whose presence reflected the extent of radiation-induced bone marrow injury. Different water content in proliferating hematopoietic tissue and adipose tissue enabled clear distinction of the two components even inside the same vertebral body. Three patterns of bone marrow viability were observed in irradiated patients: 1. Patients undergoing therapy at the time of MR study, and patients who had received low-intermediate dose several years before MR examination showed no alteration as compared with healthy controls (i.e. homogeneous presence of red marrow). 2. Patients who had received low-intermediate dose few years before MR, showed either partial re-colonization of yellow marrow or almost complete ablation of active red marrow with rare areas of re-colonization. 3. Patients who had received high dose, showed complete depletion of red marrow (fatty substitution) independently of the length of time elapsed since radiation therapy. Therefore, bone marrow recovery after radiation therapy was associate with two variables: received dose and length of time allowed for re-colonization by surviving hematopoietic tissue. In conclusion, our results provide evidence that MR can be purposively used to study composition and distribution of normal bone marrow, and to asses the extent of radiation-induced bone marrow injury; to monitor bone marrow recovery (or the lack of it); and in the general follow-up of treated cancer patients.

Adolescent↗

Magnetic resonance in the study of cranial nerves.

The course of cranial nerves was studied by means of magnetic resonance (MR), which allowed a multiplane visualization of the investigated structures. The obtained results showed that MR was an excellent method for visualization of the optic, trigeminal, facial and acoustica nerves. The oculomotor and the abducent nerves were detectable only in some regions where the contrast with the surrounding structures was greater. The glossopharingeus, vegus and accessory nerves were identifiable only in the first tract of emergency from the encephalic trunk and they could no be distinguished separately. The trochlear nerve was seldom visible whereas the olfactory nerve failed to be revealed. Further technological progress will allow for additional advances as regards the acquisition of knowledge concerning these important nerves.

Adult↗