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AIM: To investigate the diagnostic accuracy of dual-energy multidetector computed tomography (MDCT) with iodine quantification compared to conventional enhancement measurements in distinguishing bland from neoplastic portal vein thrombosis in patients with hepatocellular carcinoma. MATERIAL AND METHODS: Thirty-four patients (26 men, eight women; mean age, 62 years) with hepatocellular carcinoma and portal vein thrombosis underwent contrast-enhanced dual-energy MDCT during the late hepatic arterial phase for the assessment of portal thrombosis (bland, n=21; neoplastic, n=13). Datasets were analysed separately by two different readers. Interobserver correlation and variability were calculated and compared with the Bland-Altman method. Diagnostic accuracy of conventional enhancement measurements and iodine quantification was calculated by setting either histopathology (n=7) or a reference standard based on MDCT imaging criteria and thrombus evolutionary characteristics compared to a previous MDCT examination (n=27). For iodine quantification threshold determination receiver operating characteristic (ROC) curves were drawn. p-Values <0.05 were considered significant. RESULTS: For conventional enhancement measurements and iodine quantification interobserver correlation was 98% and 96%. Enhancement measurement resulted in a sensitivity of 92.3%, specificity of 85.7%, positive predictive value (PPV) of 80%, and negative predictive value (NPV) of 94.7%. An iodine concentration of 0.9 mg/ml optimised discrimination between neoplastic and bland thrombi (area under the ROC [AUC] 0.993) resulting in a sensitivity of 100%, specificity of 95.2%, PPV of 92.9%, and NPV of 100%. The overall diagnostic accuracy of iodine quantification (97%) was significantly better than conventional enhancement measurements (88.2%; p<0.001). CONCLUSION: Compared to conventional enhancement measurements, iodine quantification improves the characterisation of portal vein thrombi during the late hepatic arterial phase in patients with hepatocellular carcinoma.

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The oral cavity is a complex anatomical region consisting of different anatomical sites and subsites. Cancer undoubtedly represents the most frequent and relevant disease of this region. Clinical examination is often the first approach to oral cavity tumours. Cross-sectional computed tomography (CT) and magnetic resonance imaging (MRI) play a key role in staging locoregional disease by demonstrating submucosal spread and involvement of deep layers; evaluation of specific pathways of spread to peculiar anatomical subsites is also fundamental information that can be obtained with these techniques. The purpose of this paper is to illustrate CT and MRI findings of anatomical subsites involved by tumours of the oral cavity.

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AIM: To assess the value of a single-phase dual-energy computed tomography (DECT) urography protocol with synchronous nephrographic-excretory phase enhancement and to calculate the potential dose reduction by omitting the unenhanced scan. MATERIALS AND METHODS: Eighty-four patients referred for haematuria underwent CT urography using a protocol that included single-energy unenhanced and dual-energy contrast-enhanced with synchronous nephrographic-excretory phase scans. DECT-based images [virtual unenhanced (VUE), weighted average, and colour-coded iodine overlay] were reconstructed. Opacification degree by contrast media of the upper urinary tract, and image quality of virtual unenhanced images were independently evaluated using a four-point scale. The diagnostic accuracy in detecting urothelial tumours on DECT-based images was determined. The dose of a theoretical dual-phase single-energy protocol was obtained by multiplying the effective dose of the unenhanced single-energy acquisition by two. Radiation dose saving by omitting the unenhanced scan was calculated. RESULTS: The degree of opacification was scored as optimal or good in 86.9% of cases (k = 0.72); VUE image quality was excellent or good in 83.3% of cases (k = 0.82). Sensitivity, specificity, positive predictive value, and negative predictive value for urothelial tumours detection were 85.7, 98.6, 92.3, and 97.1%. Omission of the unenhanced scan led to a mean dose reduction of 42.7 ± 5%. CONCLUSION: Single-phase DECT urography with synchronous nephrographic-excretory phase enhancement represents an accurate "all-in-one'' approach with a radiation dose saving up to 45% compared with a standard dual-phase protocol.

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The aim of the present study was to detect entheseal abnormalities by means of ultrasonography (US) in patients with psoriasis. We evaluated 24 patients with psoriasis who underwent clinical and ultrasonographic examination of both lower limbs at the calcaneal insertions of the Achilles tendons and at the flexor and extensor tendons of all fingers of the hand. Fourteen patients with psoriatic arthritis were used as controls. US was performed using a real-time scanner (ATL SDI 3000) with a 5-12 MHz linear array transducer. Longitudinal and transverse scans of the talocrural joints, Achilles tendons and both the flexor and extensor tendons of the fingers of both hands were obtained at rest and during active and passive movements. On clinical examination no entheseal site was abnormal, but on US examination 33% of patients showed abnormalities. In particular, six psoriasis patients (25%) who were asymptomatic showed effusion around the extensor tendon of the first digit of the left hand and around the extensor tendon of the third and fourth digits of both hands; two patients (8.3%) showed a hypoechoic nodular formation of the flexor tendon sheath of the left hand. We conclude that entheseal abnormalities not detected at clinical examination were present in 33% of patients with psoriasis who underwent US examination. Therefore, we suggest the routine use of ultrasonography in the early diagnosis and in treatment and follow-up of patients with tendon enthesopathy, since these factors may have implications for therapy.

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Liparitosis is a rare pneumoconiosis determined by inhalation of pumice, an amorphous complex silicate extracted in the quarries of Lipari (Aeolian Archipelago, Italy). We describe two cases of subjects occupationally exposed to pumice dust in which high-resolution computed tomography (HRCT) revealed the presence of pleural lesions without parenchymal involvement.

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The term "pseudotumor" is used to refer to several anatomic variants that can simulate a renal mass, the most frequent of which are hypertrophied column of Bertin, persistence of fetal lobation, and the dromedary or splenic hump. We describe the findings of power Doppler US after the ultrasound contrast agent (Levovist, Schering, Berlin, Germany) administration in 4 patients with a renal focal lesion in whom gray-scale and baseline power Doppler US was not able to certainly differentiate pseudotumor from neoplasm.

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PURPOSE: To evaluate the accuracy of MR pyelography in the assessment of hydroureteronephrosis. MATERIAL AND METHODS: One hundred and fifteen patients, with variable degree of hydroureteronephrosis demonstrated by US and urography were subjected to MR pyelography obtained by means of two ultra-fast sequences. RESULTS: Of the 228 kidneys examined, the collecting systems of 130 kidneys were dilated and correctly identified on MR pyelography, with only 2 false-positive results. The specificity of MR pyelography in detecting hydronephrosis was 98%. Accuracy in revealing level of obstruction was 100%. Sensitivity in detecting stones, strictures and congenital ureteropelvic junction obstructions was respectively 68.9%, 98.5% and 100%. CONCLUSION: MR pyelography can rapidly and accurately depict the morphological features of dilated urinary tracts with information regarding the degree and level of obstruction, without using contrast medium or ionizing radiation.

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We describe four cases of portal vein aneurysm that were studied with ultrasonography, color Doppler, computed tomography, and magnetic resonance imaging as well as three-dimensional power Doppler. Three-dimensional ultrasonography showed the portal aneurysm and its relationship to its portal branches in all patients and showed the portosystemic communication in three. In all cases, computed tomography or magnetic resonance imaging confirmed the three-dimensional ultrasonographic findings.

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BACKGROUND: In a prospective study, we compared power Doppler with and without contrast medium in the depiction of vascularity for the characterization of hyperechoic renal lesions. METHODS: Forty-one hyperechoic renal expansive lesions (29 benign, 12 malignant) in 32 patients were studied with power-Doppler ultrasonography before and after administration of an echo-enhancing agent (Levovist Schering AG, Berlin, Germany). Vascular architecture of the lesions was categorized into five different patterns. RESULTS: Power Doppler ultrasonography showed vascular structures in 25 lesions. The study enhanced with Levovist showed vascularity in eight of 16 lesions not seen on the unenhanced study. The characterization of vascular patterns with unenhanced power Doppler ultrasonography improved diagnostic accuracy compared with gray-scale ultrasonography (59% vs. 32%). The combination of B mode and power Doppler produced even greater diagnostic accuracy (78%), independent of the administration of echo-enhancing agent. Levovist administration was useful in the differential diagnosis between pseudotumor and neoplasm. CONCLUSION: The use of sonographic contrast agent did not increase the diagnostic accuracy of power Doppler in the differential diagnosis of hyperechoic renal lesions but was advantageous for the characterization of suspected pseudomasses.

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Endovascular repair of infrarenal abdominal aortic aneurysms is currently widely diffuse. Imaging plays a major role in the preprocedural patient evaluation, implantation of stent-graft, and patient follow-up. The aim of this paper is to describe the more frequent findings that can be seen in CT examinations after endovascular repair of infrarenal abdominal aortic aneurysm. We discuss CT findings related to the aneurysm (size, exclusion with complete perigraft thrombosis, back-filling of aneurysm sac via branch vessels) and to the device (dislocation, rotation, kinking, device expansion, patency/thrombosis, device disruption). We also show some examples of incorrect assembly of the modular components of the stent-graft.

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UNLABELLED: Primary vesicoureteral reflux is a predisposing factor for urinary tract infections in children. The first-choice technique for the diagnosis of vesicoureteral reflux is voiding cystourethrography, followed by cystoscintigraphy; cystoscintigraphy, however, has the advantage of only minor irradiation of the patient, but it does not allow the morphological evaluation of bladder and vesicoureteral reflux grading. Colour-Doppler cystosonography with echocontrast is a recently introduced method for imaging vesicoureteral reflux. The aim of our study is to evaluate the role of colour-Doppler cystosonography with echocontrast in the diagnosis of vesicoureteral reflux. Twenty children (11M, 9F) aged between 0.4 and 4.9 y underwent colour-Doppler cystosonography using a diluted solution of Levovist (Schering, Germany), after filling up the bladder with saline. In all patients, vesicoureteral reflux diagnosis and grading had been performed previously by voiding cystourethrography within 5 d from ultrasonography. Our data showed high accuracy in the detection of medium to severe vesicoureteral reflux (grades III-V), confirmed by radiological features in 9/9 patients. Conversely, in the 11 patients with mild vesicoureteral reflux (grades I-II), this technique showed extremely low sensitivity, allowing diagnosis in only four cases. CONCLUSIONS: Colour-Doppler cystosonography, because of the absence of ionizing radiations, has great advantages, particularly in patients needing prolonged monitoring. Despite experiences reported in the literature, this technique has a role in the diagnosis of vesicoureteral reflux. Our group chooses colour-Doppler cystosonography for the follow-up of medium-severe grade vesicoureteral reflux already diagnosed by radiology and/or scintigraphy. Cystoscintigraphy is employed only to confirm cases resulting negative at ultrasonography.

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Hepatic angiomyolipoma (AML) is a rare tumor containing a variable amount of fat. Angiomyolipoma prevalently constituted by vessels can be difficult to differentiate from other hypervascular hepatic tumors containing a small amount of fat. We describe US power Doppler findings in a case of hepatic AML with minimal fat content.

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STUDY OBJECTIVE: To determine the value of gadolinium-enhanced MRI in the assessment of disease activity in chronic infiltrative lung diseases (CILDs). DESIGN: Retrospective study. SETTING: University hospital. MATERIALS AND METHODS: Twenty-five consecutive patients with CILD were studied. The following diseases were diagnosed: sarcoidosis (n = 10), bronchiolitis obliterans organizing pneumonia (n = 3), usual interstitial pneumonia (n = 4), radiation pneumonia (n = 2), desquamative interstitial pneumonia (n = 1), rheumatoid lung (n = 1), vasculitis (n = 1), alveolar proteinosis (n = 1), bronchioloalveolar carcinoma (n = 1), and chronic eosinophilic pneumonia (n = 1). In each patient, the disease activity was assessed by one or more of the following studies: BAL (n = 18), gallium-radioisotope lung scanning (n = 6), serum angiotensin-converting enzyme assay (n = 10), and open lung biopsy (n = 4). T1-weighted breath-hold MRI studies were obtained before and after IV injection of gadolinium. The MRI examinations were analyzed to assess the presence or absence of lesional enhancement. RESULTS: The presence of enhanced pulmonary lesions was seen in 14 patients. All of these patients had active disease. Of the 17 patients with active disease, 14 had enhanced lesions, and 3 had unenhanced lesions. Pulmonary lesions were not enhanced in any patients with inactive disease. The difference was statistically significant (Fisher Exact Test, p < 0.05). CONCLUSION: Gadolinium-enhanced MRI may prove to be a useful tool in assessing disease activity in CILDs.

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PURPOSE: To evaluate the best position of the arms in mantle field for Hodgkin's disease. METHODS AND MATERIALS: In 12 patients, with surgical clips placed at the time of an axillary dissection for breast cancer, the radiological projection of the clips according to three arm positions was prospectively evaluated: akimbo (A), extended (E), and up over the head (U). The surgical clips were arbitrarily separated into two groups: lower and upper. In each patient, the distance between the surgical clips and chest wall was measured, and the possibility of shielding the lungs and humeral heads was evaluated. RESULTS: The mean displacement of the lower clips away from the chest wall when the patients were in A, E, and U positions was 2.5, 3.0, and 4.6 cm, respectively. The upper group clips showed a lower difference in distance from chest wall. In the U position, there was always a clip of the lower group that projected over the humeral head, making it impossible to block this structure. CONCLUSION: In the A position, there is the possibility of blocking the humeral head, but it is necessary to irradiate more lung parenchyma. Type E treatment setup allows the shielding of both lung and humeral head, while maintaining adequate margins around the axillary nodes. In the U position, there is a greater possibility of shielding the lung parenchyma, but it is impossible to block the humeral heads.

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The purpose of this study is to describe the magnetic resonance (MR) features of bronchioloalveolar carcinoma. MR examinations of 18 patients with proven bronchioloalveolar carcinoma were reviewed. Detection at computed tomography (CT) and pathologic confirmation were the entry criteria. Nine patients had a solitary nodule, three patients a lobar consolidation, and six patients had diffuse disease. For each patient, both breath-hold T2-weighted fast spin-echo, and breath-hold T1-weighted gradient-echo images, before and after injection of gadolinium, were available. Nine patients with pulmonary consolidation or diffuse disease had also heavily T2-weighted MR imaging (Haste or TSE 240; Siemens, Erlangen, Germany). MR imaging showed pulmonary abnormalities in 17 of 18 patients. Unenhanced T1-weighted and T2-weighted images depicted tumor in 16 of 18 patients. Contrast-enhanced T1-weighted images showed tumor in 17 of 18 patients. In no case did MR imaging depict abnormalities corresponding to the ground-glass opacities seen on CT scans. In three patients with mucinous bronchioloalveolar carcinoma, heavily T2-weighted images showed lesions isointense with respect to static fluid of the human body. In conclusion, the ability of MR imaging in detecting small nodules and ground-glass opacities is limited. However, heavily T2-weighted sequences are able to show the presence of mucin. This is useful information because mucinous bronchioloalveolar carcinoma carries a poor prognosis.

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PURPOSE: To report the results of a prospective study investigating the potentials of contrast-enhanced power Doppler in the diagnosis of expansive renal lesions. MATERIAL AND METHODS: From 1997 to October 30, 1999, we studied 59 expansive renal lesions (28 malignant, 31 benign) in 48 patients (mean age 55 years, range 10-79) with power Doppler US before and after the administration of an echo-enhancing agent (Levovist, Schering AG, Berlin, Germany). We identified 5 patterns of vascular architecture of the lesions, both before and after contrast agent administration, following the classification by Jinzaki e Coll. RESULTS AND DISCUSSION: Power Doppler US showed vascular structures in 34 patients. The administration of Levovist revealed vessels in 12/25 lesions which had none at baseline studies and in 6 cases vascularity was particularly evident. Color signals were enhanced in all the 34 vascularized lesions, which allowed better definition of vascular patterns. The characterization of vascular patterns with baseline power Doppler US helped improve diagnostic accuracy compared to gray-scale US (58% versus 32%) for hyperechoic lesions, complex cysts and pseudomasses. Independent of contrast agent administration, the integration of gray-scale and power Doppler modes increased diagnostic accuracy even further (76% correct diagnoses). CONCLUSIONS: In our series, the US contrast agent did not increase the diagnostic accuracy of power Doppler in the differential diagnosis of hyperechoic renal lesions; conversely, Levovist can be advantageous for the characterization of suspected pseudomasses and complex cysts.

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Breath-hold MR urography (MRU) is being used with increasing frequency to evaluate urinary tract pathology. Although multiple studies have documented the accuracy of breath-hold MRU in the evaluation of obstructive uropathy, pitfalls associated with this technique may result in diagnostic errors. This essay illustrates both technical and interpretive pitfalls of MRU and suggests strategies for their recognition and avoidance.

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INTRODUCTION: Functional endoscopic sinus surgery has become the technique of choice to treat benign or inflammatory diseases of paranasal sinuses resistant to medical therapy. The goal of this type of surgery is to open the obstructed sinus ostia and restore normal aeration and mucociliary clearance. Messerklinger's is the most widely used technique. PURPOSE: We investigated the role of CT after functional endoscopic sinus surgery and describe CT findings of postoperative anatomical changes together with frequent complications and surgical failures. METHODS AND MATERIALS: Twenty-seven patients with relapsing symptoms were examined with CT of paranasal sinuses 8-32 weeks after functional endoscopic sinus surgery. In all cases both preoperative CT and surgical reports were available: CT and surgical results were compared. RESULTS: In 21/27 patients nasosinusal changes were demonstrated with CT. Recurrent disease secondary to inflammation and/or fibrosis was observed in 14 cases. Residual disease was seen in 5 patients. A major orbital complication was found in 1 patient with diplopia. One patient exhibited a large interruption of cribriform plate with CSF fistula. CONCLUSION: CT permitted an accurate assessment of extension and results of functional endoscopic sinus surgery. CT is indicated in the postoperative study of the patients who a) present symptoms of cerebral and ocular complications (early after functional endoscopic sinus surgery); and b) do not respond to medical treatments 8-32 weeks after unsuccessful functional endoscopic sinus surgery. In these patients CT can demonstrate recurrent and/or residual nasosinusal disease and bony defects unintentionally caused by the surgeon during the procedure.

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Mucinous cystadenocarcinoma (MCA) is a rare tumor that is considered to be a cystic variant of mucin-producing lung adenocarcinoma. MCA expands grossly by storing mucus and contains few neoplastic cells. We present the CT images of three patients with MCA and correlate them with pathologic specimens. The CT findings of MCA include a uniform low-attenuation, focal thickening of the cystic wall and enhancing septa.

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