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Purpose: Hypertrophic cardiomyopathy (HCM) is a hereditary disease characterised by primary hypertrophy of the left and/or right ventricle. The reference standard for imaging diagnosis is echocardiography. The aim of our study was to prospectively compare the diagnostic accuracy of echocardiography and cardiac magnetic resonance (MR) imaging in patients with HCM., Materials and Methods: Twenty-two consecutive patients with a known diagnosis of HCM were prospectively evaluated, with echocardiography and cardiac MR imaging performed within 2 weeks of each other (mean interval 7 days, range 2-14 days). Two experienced radiologists blinded to the previous clinical and imaging findings separately reviewed the images. The following parameters were calculated for both techniques: myocardial mass, wall thickness, end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), systolic anterior motion (SAM) of the mitral valve and degree of myocardial fibrosis (based on the ultrasonic reflectivity at echocardiography and degree of late enhancement at cardiac MR imaging). The statistical correlation was calculated with Student's t test, Spearman coefficient and Fisher's exact test. A value of p<0.05 was considered significant., Results: The diagnosis of HCM was confirmed in all patients with both techniques, with absolute agreement in terms of the site of disease. The mean value of myocardial mass presented a statistically significant difference between the two techniques (114 g, p<0.001). In contrast, a nonsignificant difference between echocardiography and cardiac MR imaging was found for EDV (102 ml vs 111 ml; p=0.31), ESV (30 ml vs 38 ml; p=0.1), EF (74% vs 68%, p=0.5), SAM (p=0.1) and myocardial fibrosis (p=0.15)., Conclusions: Cardiac MR imaging correlates well with echocardiography in defining the morphological and functional parameters useful for the imaging diagnosis of HCM and therefore, in selected cases (poor acoustic window, doubtful echocardiography findings), it may be a valid alternative to echocardiography.

Purpose: The authors sought to compare the sensitivity and reading time obtained using computer-aided detection (CAD) software as second reader (SR) or concurrent reader (CR) in the identification of pulmonary nodules., Materials and Methods: Unenhanced CT scans of 100 consecutive cancer patients were retrospectively reviewed by four readers to identify all solid, noncalcified pulmonary nodules ranging from 3 to 30 mm in diameter. The sensitivity and reading time of each reader and of CAD alone were calculated at 3-mm and 5-mm thresholds with respect to the reference standard, consisting of a consensus reading by the four radiologists involved in the study. The McNemar test was used to compare the sensitivities obtained by reading without CAD (readers 1 and 2), with CAD as SR (readers 1 and 2 with a 2-month delay), and with CAD as CR (readers 3 and 4). The paired Student's t test was used to compare reading times. A value of p<0.05 was considered statistically significant., Results: A total of 258 and 224 nodules were identified at 3-mm and 5-mm thresholds, respectively. The sensitivity of CAD alone was 62.79% and 67.41% at the 3-mm and 5-mm threshold values respectively, with 4.15 and 2.96 false-positive findings per examination. CAD as SR produced a significant increase in sensitivity (p<0.001) in nodule detection with respect to reading without CAD both at 3 mm (12.01%) and 5 mm (10.04%); the average increase in sensitivity obtained when comparing CAD as SR to CAD as CR was statistically significant (p<0.025) both at the 3-mm (5.35%) and 5-mm (4.68%) thresholds. CAD as CR produced a nonsignificant increase in sensitivity compared with reading without CAD (p>0.05). Mean reading time using CAD as SR (330 s) was significantly longer than reading without CAD (135 s, p<0.001) and reading with CAD as CR (195 s, p<0.025)., Conclusions: The use of CAD as CR, without any significant increase in reading time, produces no significant increase in sensitivity in pulmonary nodule detection when compared with reading without CAD (p>0.05); CAD as SR, at the cost of longer reading times, increases sensitivity when compared with reading without CAD (p<0.001) or with CAD as CR (p<0.025).

Purpose: This study was undertaken to establish the reliability of automated volumetric liver scans in detecting focal liver lesions by evaluating the degree of agreement between conventional and volume ultrasound (US) examinations., Materials and Methods: Over a period of 3 months, we prospectively studied 100 consecutive patients (36 men and 64 women; age range 15-87 years; mean age 63 years) referred to our institute for US imaging of the liver. Volumetric acquisition of the liver was achieved with a 3D transducer (2.0-5.0 MHz) and a Logiq 9 US scanner. All patients underwent both 2- and 3D US studies performed by two expert radiologists. Volumetric acquisitions were subsequently reviewed by the second radiologist, who was blinded to the first radiologist's report. Three categories were established: 1=presence of focal liver lesions; 2=doubtful finding; 3=absence of focal liver lesions. Concordance between volume US and conventional US was calculated by using the k statistic., Results: Out of 100 patients examined, 39 were found to be affected by focal liver lesions. All volume US examinations were technically adequate, allowing exploration of all hepatic sectors, except for five cases that were marred by major respiratory motion artefacts. Conventional and volume US identified the same number of focal liver lesions, with the exception of four cases of doubtful findings at volume US. Concordance between automated volume US and conventional US of the liver was high (k=0.92)., Conclusions: The identification of focal liver lesions on automated volume US is possible, and the examination shows a high level of concordance with conventional US.

This paper highlights the differences among the most common file formats used for storing digital radiological images. It promotes the proper use of these formats to guarantee easy manipulation in handling the most typical practical applications in daily radiological practice. The authors provide a simple yet exhaustive introduction to the concept of "file format" and describe the algorithms and main features of the most common formats (BMP, JPEG, GIF, DICOM, TIF, PNG) and Portable Network Graphics (PNG).The different formats are compared in terms of dimension, quality, portability and with reference to the following specific needs: electronic communications, publication on the World Wide Web, presentation of electronic posters, video presentations for teaching and manuscript publishing. We also illustrate how to handle the various formats with the programmes supplied with standard software installations.The large number of digital applications of image file formats calls for a simplification in daily radiological practice. We recommend the use of JPEG and PNG for electronic communications; PNG and GIF for publication on the worldwide web; JPEG and PNG for electronic poster presentations; DICOM, PNG and JPEG for teaching presentations; TIF and PNG for printing on paper.

Purpose: This study aimed to evaluate the diagnostic value of contrast-enhanced ultrasound (CEUS) in characterising focal liver lesions in cirrhosis and to validate its use in lesions discovered during surveillance for hepatocellular carcinoma (HCC)., Materials and Methods: Between 2003 and 2006, 128 cirrhotic patients with focal liver lesions at baseline ultrasonography (US) were studied by power colour Doppler US (Doppler US) and CEUS. Serum alpha-fetoprotein (AFP) levels were assessed in all patients. Fine-needle biopsy or other reference modalities such as computed tomography (CT), magnetic resonance imaging (MRI) or digital subtraction angiography (DSA) were used as the gold standard. The accuracy of baseline US, Doppler US, AFP levels, combined US and AFP levels and combined US, Doppler US and CEUS in characterising focal liver lesions was assessed. Diagnostic performance was compared using the McNemar test., Results: A total of 207 focal liver lesions (101 benign and 106 malignant) were identified in 128 patients. CEUS sensitivity and specificity for lesion characterisation were 96.2% and 97.0%, respectively, whereas its positive and negative predictive values were 97.1% and 96.1%. CEUS accuracy was 96.6%, higher than that of US (72.0%), Doppler US (70.0%), AFP levels (65.7%), combined US and Doppler US (70.0%) and combined US and AFP levels (90.3%). The differences between US and CEUS were statistically significant (p<0.05)., Conclusions: CEUS can characterise focal liver lesions with 96.6% accuracy, a value higher than US, Doppler US, AFP levels, combined US and AFP levels and combined US and Doppler US. CEUS should therefore be used to characterise focal liver lesions detected during HCC surveillance of cirrhotic patients.

Purpose: The aim of this study was to illustrate the different imaging features of middle and inner ear implants, brainstem implants and inferior colliculus implants., Materials and Methods: We retrospectively reviewed the computed tomography (CT) images of 468 patients with congenital or acquired transmissive or neurosensory hearing loss who underwent surgery. The implants examined were: 22 Vibrant Soundbridge implants, 5 at the long limb of the incus and 17 at the round window, 350 cochlear implants, 95 brainstem implants and 1 implant at the inferior colliculus. All patients underwent a postoperative CT scan (single or multislice scanner) and/or a Dentomaxillofacial cone-beam CT scan (CBCT) (axial and multiplanar reconstruction), and/or a plain-film radiography to visualise the correct position of the implant., Results: The CBCT scan depicts Vibrant site of implant better than plain-film radiography, with a lower radiation dose compared to CT. For cochlear implants, a single plain radiograph in the Stenvers projection can directly visualise the electrodes in the cochlea. All patients with brainstem or inferior colliculus implants underwent postoperative CT to exclude complications and the assess correct implantation, but the follow-up of these implants can be performed by plain radiography alone., Conclusions: CT and CBCT scans are reliable and relatively fast methods for precisely determining the location of middle ear implants. CBCT is preferable to CT because of the lower radiation dose administered; a single plain-film radiograph is enough to visualise and follow-up cochlear, brainstem and inferior colliculus implants.

Purpose: This study was done to compare the perfusion patterns of intrahepatic peripheral cholangiocarcinoma (IPCC) on contrast-enhanced ultrasound (CEUS) and dynamic computed tomography (CT)., Materials and Methods: We retrospectively reviewed 23 histologically proven cases of IPCC. All lesions were studied by CEUS with sulfur hexafluoride-filled microbubbles coated with a phospholipid capsule, and by dynamic CT. Contrast-enhancement patterns were evaluated in the arterial phase (CEUS 10-20 s after the injection; CT 25-30 s after the injection) and in the delayed phase (CEUS 120 s after the injection; CT>2-3 min after the injection)., Results: Lesions were single in 18/23 cases (78%), single with nearby satellite lesions in 1/23 (4%) cases and multifocal with distant secondary lesions in 4/23 (17%) cases. Lesion diameter was 2-5 cm in 7/23 cases (30%), 5-7 cm in 13/23 cases (57%) and >7 cm in 3/23 (13%) cases. On CEUS, lesions were hypervascular in 16/23 cases (70%). On delayed-phase CEUS, 22/23 lesions (96%) were markedly hypoechoic. CT showed that the lesions were hypovascular in the arterial phase in 15/23 cases (66%) and hypervascular in 7/23 (30%) cases; one lesion (1/23; 4%) was isovascular. On delayed-phase CT, lesions were hyperdense in 17/23 cases (74%), hypodense in 5/23 (22%) cases and isodense in 1/23 (43%) cases., Conclusions: Enhancement discrepancy between delayed-phase CEUS (hypoechogenicity) and CT (hyperdensity) is common semiological findings in the study of IPCC.

Purpose: The aim of this study was to perform a cost analysis of contrast-enhanced ultrasonography (CEUS) in the study of benign focal liver lesions (BFLL) with indeterminate appearance on ultrasonography (US)., Materials and Methods: A decision model of patients with suspected BFLL on baseline US who subsequently underwent CEUS between 2002 and 2005 was constructed. We analysed the cost effectiveness of CEUS, considering whether or not computed tomography (CT) was necessary for the diagnosis. There were 398 patients with 213 angiomas, 41 focal nodular hyperplasias (FNH) and 154 pseudolesions (focal fatty sparing, focal fatty areas). Each patient underwent CEUS, and 98 of them were also studied by CT. All lesions were followed up., Results: The cost of a single CEUS examination was 101.51 euros, and that of a single CT scan was 211.48 euros. For diagnosis of haemangiomas, we saved 1,406.97 euros in 2002, 5,315.22 euros in 2003, 10,317.78 euros in 2004 and 9,536.13 euros in 2005. For diagnosis of focal nodular hyperplasias, we saved 781.65 euros in 2003, 781.65 euros in 2004 and 1,406.97 euros in 2005. For diagnosis of pseudolesions, we saved 2,813.94 euros in 2002, 5,158.89 euros in 2003, 5,158.89 euros in 2004 and 4,220.91 euros in 2005. In the period 2002-2005, the introduction of CEUS allowed us to save a total of 47,055.33 euros in the diagnosis of benign focal hepatic liver lesions., Conclusions: This cost analysis shows that CEUS is the least expensive second-line modality after baseline US for the diagnosis of BFLL.

Purpose: This study was done to assess the progression of cartilage repair after autologous chondrocyte implantation (ACI) with magnetic resonance imaging (MRI) and to correlate the findings with the clinical outcome., Materials and Methods: Forty-one patients (mean age 30 years) affected by chondral defects of the knee (27 patients) and ankle joint (14 patients) who underwent arthroscopic autologous osteochondral grafting were studied 6 months and 1 year postoperatively with MRI. Cartilage repair after chondrocyte implantation was studied by assessing the degree of defect filling, graft integration, graft signal intensity, integrity of the subchondral lamina and trabecular oedema underneath the graft. MR findings were correlated with clinical data., Results: Postoperative MRI evaluation at 6 months demonstrated complete filling of the osteochondral defect in 12/41 cases, complete integration in 18/41, mild hyperintensity in 28/41, intact subchondral lamina in 38/41 and trabecular oedema in 11/41. Postoperative MRI evaluation at 1 year demonstrated complete filling of the osteochondral defect in 9/41 patients, complete integration in 22/41, mild hyperintensity in 23/41, intact subchondral lamina in 36/41 and trabecular oedema in 8/41. Filling of the osteochondral defect and incomplete integration, nonintact subchondral lamina, high signal intensity and absence of oedema were found to correlate with worse clinical-functional outcomes., Conclusions: MRI shows direct prognostic signs of the clinical outcome of ACI.

Purpose: The purpose of this study was to evaluate the applications of magnetic resonance imaging (MRI), and in particular, dynamic contrast-enhanced MRI (DCE-MRI), in the assessment of tumour microvasculature by means of animal tumour models evaluated before and after antiangiogenic treatment., Materials and Methods: Forty-two MRI exams were performed with intravascular contrast media in 21 rats: tumours were induced by subcutaneous injection of colon carcinoma cells in 7 rats and mammary adenocarcinoma cells in 14 rats. Perfusion and permeability parameters of the implanted tumours were evaluated by using two contrast media (B22956/1 and Gd-DTPA37-albumin) to establish response to treatment with two different antiangiogenic drugs (tamoxifen and SU6668). These parameters were correlated with histology to obtain a radiological-histological map of tumour microvasculature., Results: DCE-MRI revealed greater enhancement in the peripheral area than in the central area in all the examined animal models. In the mammary carcinoma experiment, vascular permeability measured by means of B22956/1 in the animals treated with the antiangiogenic drug (0.0043317+/-0.0040418 ml/min(-1)/ml(-1)) was significantly less than in untreated animals (0.0090460+/-0.0043680 ml/min(-1)/ml(-1)), whereas no significant difference was observed with Gd-DTPA-albumin (13.14+/-13.94 ml/min(-1)/ml(-1) in treated animals and 18.07+/-11.92 ml/min(-1)/ml(-1) in untreated animals). In the colon carcinoma experiment, mean permeability and perfusion decreased by 51% (from 5.2+/-1.1 to 2.5+/-0.8 ml/100 ml) and 59% (from 0.00165+/-5.1 to 0.0067+/-4.8 ml/min(-1)/ml(-1) of tissue), respectively, in all animals after antiangiogenic drug administration., Conclusions: DCE-MRI permits a noninvasive evaluation of tumour microcirculation and in particular of its dynamic characteristics and vascularity before and after antiangiogenic treatment.

Purpose: The purpose of this study was to evaluate the reliability of computed tomography (CT) and magnetic resonance imaging (MRI) in characterising cochlear nerve anomalies in auditory brainstem implant candidates with congenital hearing loss., Materials and Methods: Seventeen patients affected by congenital sensorineural hearing loss were examined by CT and MRI. Inner ear malformations eligible for auditory brainstem implants were classified according to the Casselman classification. All patients subsequently received auditory brainstem implants., Results: Suspected congenital anomalies were confirmed by CT and MRI in all 17 patients. There were 5/17 bilateral cochlear nerve aplasias and 12/17 cochleovestibular anomalies. Of these, 5/12 patients had a common cochleovestibular cavity, 2/12 had bilateral cochlear aplasia and cochlear nerve agenesis, 1/12 had type I incomplete partition, 2/12 had type II incomplete partition and 2/12 had cochlear hypoplasia., Conclusions: Preoperative CT and MRI assessment of patients with sensorineural hearing loss is reliable. MRI provided additional information, identifying the possible absence of cochlear nerve and excluding other central nervous system (CNS) diseases.

Purpose: The purpose of this study was to evaluate the accuracy of magnetic resonance (MR) in correctly locating and characterising biliary strictures in patients affected by extrahepatic cholangiocarcinoma, identify findings suggestive of the disease, identify lesions with similar MR features and possible criteria for differential diagnosis and establish prospective MR accuracy in diagnosis of malignant obstruction of extrahepatic bile ducts., Materials and Methods: We retrospectively reviewed the MR examinations of 39 patients affected by extrahepatic cholangiocarcinoma confirmed by histology or cytology. The studies were evaluated for the following parameters: site of obstruction (hilar, proximal or distal), presence of intra- or extrahepatic dilation of bile ducts, morphology of ductal stenosis (gradual tapering or abrupt ending), morphology of the lesion (mass like or circumferential), dimension, signal intensity before contrast medium administration and lesion enhancement after administration of contrast medium. Finally, we assessed the most useful sequence for the diagnosis. In order to evaluate MR accuracy in the diagnosis of malignant obstruction of extrahepatic bile ducts, we prospectively reviewed MR examinations of 74 patients affected by obstructive jaundice (55 malignant lesions and 19 inflammatory lesions). MR diagnosis was compared with histology or cytology considered as the gold standard., Results: MR allowed identification and localisation of 41/41 extrahepatic cholangiocarcinomas. Fifty-four percent of the lesions showed gradual duct tapering; the remaining lesions showed an abrupt ending. Fifty-six percent of the lesions appeared as a circumferential thickening (infiltrative growth); the remaining lesions had a mass-like appearance (expansile growth). Most lesions were hypo- (49%) or isointense (49%) in T1-weighted sequences and hyper- (49%) or isointense (51%) in T2-weighted sequences. Ninety-five percent of the lesions did not enhance significantly in the arterial phase while 98% showed late enhancement (10 min). The most diagnostic sequence (in 76% of cases) was the late-phase gradient-echo (GRE) T1 fat-saturated sequence. MR had good sensitivity (91%) but poor specificity (47%) in characterising stenosis as malignant, given the large number (10/19) of benign lesions evaluated as neoplastic lesions., Conclusions: MR almost always identified the cause of stenosis and suggested its neoplastic nature if it exhibited a mass-like appearance (extraductal or growing into the choledochus). On the other hand, lesions with parietal thickening, particularly if smaller than 1 cm, require endoscopic cytology or histology because of the high risk of unnecessary procedures for benign lesions.

Purpose: This study prospectively compares Doppler ultrasound (Doppler US) and contrast-enhanced magnetic resonance angiography (CE-MRA) with digital subtraction angiography (DSA) and endarterectomy findings to determine the accuracy in assessing carotid artery stenosis., Materials and Methods: Thirty-two patients underwent carotid endarterectomy, 21 studied with Doppler US, CE-MRA and DSA and 11 with Doppler US and CE-MRA. In 41 carotid arteries, the degree of stenosis was analysed with Doppler US and CE-MRA and compared with DSA by using the Spearman rank correlation coefficient. Nine out of 32 endarterectomies were done using the eversion technique, and it was possible to compare Doppler US, CE-MRA and DSA with the specimen measurement. Twenty-three out of 32 endarterectomies were done using the standard technique, and the presence of ulcers was documented., Results: There was a significant Doppler US/DSA (Rs=0.86; p<0.001) and CE-MRA/DSA (Rs=0.81; p<0.001) correlation for the degree of stenosis. The diagnostic accuracy of the three methods was the same (89%). Ulcers were most frequently seen at CE-MRA, with a diagnostic accuracy of 85%., Conclusions: These data suggest that endarterectomy on the basis of Doppler US and CE-MRA can be considered appropriate. CEMRA was the best noninvasive imaging modality to detect plaque ulceration.

Purpose: To assess the accuracy of ultrasonography (US) in the identification and grading of hepatic fibrosis in patients afflicted with chronic viral liver disease, compared to histological examination as a gold standard., Materials and Methods: We prospectively studied 105 patients (32 F, 73 M) affected by chronic viral liver disease in 36 months. Patients were studied with B-mode US and then underwent US-guided liver biopsy. All the patients were studied with conventional US with a Sequoia 512, 6.0 (Acuson, Mountain View CA, USA). We evaluated the following US parameters: liver margins, parenchymal echotexture, portal vein caliber and spleen diameter. The four B-mode US parameters were used for the US grading (from 0 to 4). Scheuer's grading (from 0 to 4) was used for the histological score. Grades 3 and 4 were considered as positive for fibrosis. Sensitivity, specificity, positive and negative predictive values and accuracy were calculated in the case of absence, positivity of one or all the US parameters. The correlation between US and histological scores was evaluated with Spearman's test., Results: At histology seventy-seven patients (73%) had absent grade 0 (1 patient; 1%), low-moderate grade 1 (35 patients; 33%) or grade 2 (41 patients; 39%) liver fibrosis. Twenty-eight patients (27%) had severe grade 3 (16 patients; 15%) or grade 4 (12 patients; 11%) fibrosis. In the case of absence of US parameters sensitivity was 32%, specificity 32%, positive predictive value 15%, negative predictive value 57% and accuracy 32%. In the case of positivity of at least one of the US parameters the values were 68%, 68%, 43%, 84% and 69%. In the case of presence of all the US signs the results were 25%, 100%, 100%, 79% and 80%. None of the 77 patients with a healthy liver or with low-grade fibrosis was positive for all the US parameters. All the patients positive for all of the ultrasonographic parameters had high-grade fibrosis or cirrhosis at liver biopsy. Correlation between B-mode and histological scores was not statistically significant (Rs=0.45; p=0.0001)., Conclusions: US identification of liver fibrosis in chronic liver disease is possible with 25% sensitivity, 100% specificity, 100% positive predictive value and 79% negative predictive value, with an 80% diagnostic accuracy.

Purpose: To evaluate the accuracy of MRCP in diagnosing choledocholithiasis considering Endoscopic Retrograde Cholangiopancreatography (ERCP) as the gold standard. To compare the results achieved during the first two years of use (1999-2000) of Magnetic Resonance Cholangiopancreatography (MRCP) in patients with suspected choledocholithiasis with those achieved during the following two years (2001-2002) in order to establish the repeatability and objectivity of MRCP results., Materials and Methods: One hundred and seventy consecutive patients underwent MRCP followed by ERCP within 72 h. In 22/170 (13%) patients ERCP was unsuccessful for different reasons. MRCP was performed using a 1.5 T magnet with both multi-slice HASTE sequences and thick-slice projection technique. Choledocholithiasis was diagnosed in the presence of signal void images in the dependent portion of the duct surrounded by hyperintense bile and detected at least in two projections. The MRCP results, read independently from the ERCP results, were compared in two different and subsequent periods., Results: ERCP confirmed choledocholithiasis in 87 patients. In these cases the results of MRCP were the following: 78 true positives, 53 true negatives, 7 false positives, and 9 false negatives. The sensitivity, specificity and accuracy were 90%, 88% and 89% respectively. After the exclusion of stones with diameters smaller than 6 mm, the sensitivity, specificity and accuracy were 100%, 99% and 99%, respectively. MRCP accuracy was related to the size of the stones. There was no significant statistical difference between the results obtained in the first two-year period and those obtained in the second period., Conclusions: MRCP is sufficiently accurate to replace ERCP in patients with suspected choledocholithiasis. The results are related to the size of stones. The use of well-defined radiological signs allows good diagnostic accuracy independent of the learning curve.