Diagnostic accuracy of colour Doppler ultrasonography, CT angiography and blood-pool-enhanced MR angiography in assessing carotid stenosis: a comparative study with DSA in 170 patients.

PURPOSE: This study was undertaken to prospectively evaluate the diagnostic performance of colour Doppler ultrasonography (CDUS), first-pass (FP) and steady-state (SS) contrast-enhanced magnetic resonance angiography (MRA) and computed tomography angiography (CTA) of the carotid arteries using digital subtraction angiography (DSA) as the reference standard. MATERIALS AND METHODS: A total of 170 patients with previous cerebrovascular events and suspected carotid artery stenoses underwent CDUS, blood-pool MRA, CTA and DSA. Accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for CDUS, FP MRA, SS MRA and CTA. The McNemar and Wilcoxon tests and receiver operating characteristic (ROC) curve analysis were used to determine significant differences (p<0.05) between the diagnostic performances of the four modalities, and the degree of stenosis was compared using linear regression. RESULTS: A total of 336 carotid bifurcations were studied. The area under the curve (AUC) for degree of stenosis was: CDUS 0.85±0.02, FP MRA 0.982±0.005, SS MRA 0.994±0.002 and CTA 0.997±0.001. AUC analysis showed no statistically significant difference between CTA and MRA (p=0.0174) and a statistically significant difference between CDUS and the other techniques (p<0.001). Plaque morphology analysis showed no significant difference between CTA and SS MRA; a significant difference was seen between CTA and SS MRA versus FP MRA (p=0.04) and CDUS (p=0.038). Plaque ulceration analysis showed a statistically significant difference between MRA and CTA (0.04< p<0.046) versus CDUS (p=0.019). CONCLUSIONS: CTA is the most accurate technique for evaluating carotid stenoses, with a slightly better performance than MRA (97% vs. 95% for SS MRA and 92% for FP MRA) and a greater accuracy than CDUS (97% vs. 76%). Blood-pool contrast-enhanced SS sequences offer improved evaluation of degree of stenosis and plaque morphology with accuracy substantially identical to CTA.

Low-dose contrast-enhanced time-resolved MR angiography at 3T: diagnostic accuracy for treatment planning and follow-up of vascular malformations.

AIM: To assess the accuracy of low-dose contrast-enhanced time-resolved 3T magnetic resonance angiography (MRA) for the morphological and functional assessment of vascular malformations (VM), and to evaluate its diagnostic potential for the depiction of treatment-induced changes. MATERIALS AND METHODS: Twenty-five patients with known VM underwent MRA to evaluate the location and extent of lesions and their haemodynamic characteristics. Three-dimensional (3D) T1-weighted time-resolved sequences were acquired following the administration of 0.05mmol/kg of gadobenate dimeglumine. VM were classified according to their morphology and haemodynamic characteristics. All patients thereafter underwent conventional angiography to confirm the diagnosis and to treat the lesions (embolization or sclerotherapy). Follow-up MRA was performed 30 days after treatment to assess morphological and functional changes. A visual analogue scale (VAS) was used to clinically assess the severity of symptoms before and after therapy. RESULTS: Based on haemodynamic characteristics, VM were classified as predominantly arterial [4 (16%)], artero-venous [19 (76%)] or venous [2 (8%)]. Twenty-three (92%) lesions were classified as high-flow VM and two (8%) as low-flow VM. Intralesional thrombosis was present in 17 (68%) lesions before therapy and in 10 lesions (40%) after therapy. The median VAS scores were 5±1 before treatment and 4±2 after treatment. Very good correlation (Spearman's correlation coefficient: rho=0.87; p=0.000) was noted between the reduction of lesion size on follow-up MRA and pain relief as assessed by VAS. CONCLUSION: Low-dose contrast-enhanced time-resolved 3T MRA can be used to define morphological and functional aspects of VM accurately during treatment planning and follow-up, and can identify post-therapy changes that positively correlate with treatment outcome.

Effect of varying contrast material iodine concentration and injection technique on the conspicuity of hepatocellular carcinoma during 64-section MDCT of patients with cirrhosis.

OBJECTIVES: The aim of this study was to compare the intraindividual effects of contrast material with two different iodine concentrations on the conspicuity of hepatocellular carcinoma (HCC) and vascular and hepatic contrast enhancement during multiphasic, 64-section multidetector row CT (MDCT) in patients with cirrhosis using two contrast medium injection techniques. METHODS: Patients were randomly assigned to one of two groups with an equal iodine dose but different contrast material injection techniques: scheme A, fixed injection duration (25 s), and scheme B, fixed injection flow rate (4 ml s(-1)). For each group, patients were randomised to receive both moderate-concentration contrast medium (MCCM) and high-concentration contrast medium (HCCM) during two CT examinations within 3 months. Enhancement of the aorta, liver and portal vein and the tumour-to-liver contrast-to-noise ratio (CNR) were compared between MCCM and HCCM. RESULTS: 30 patients (mean age 59 years; range 45-80 years; 16 patients in scheme A and 14 in scheme B) with a total of 31 confirmed HCC nodules were prospectively enrolled. For scheme B, the mean contrast enhancement of the aorta and tumour-to-liver CNR were significantly higher with HCCM than with MCCM during the hepatic arterial phase (+350.5 HU vs +301.1 HU, p = 0.001, and +7.5 HU vs +5.5 HU, p = 0.004). For both groups, there was no significant difference between MCCM and HCCM for all other comparisons. CONCLUSION: For a constant injection flow rate, HCCM significantly improves the conspicuity of HCC lesions and aortic enhancement during the hepatic arterial phase on 64-section MDCT in patients with cirrhosis.

Pathologic findings in synovial tissue of the musculoskeletal system: role of MRI in therapeutic clinic assessment.

OBJECTIVES: The clinical diagnosis of synovial lesions is difficult and radiographic findings may establish a confident diagnosis only in some cases. MR imaging has become the technique of choice in evaluating these lesions, because a presumptive diagnosis can be made in most cases. The purpose of this study was to evaluate the joint synovial disease through intravenous contrast MRI examination and the following histological validation. MATERIALS AND METHODS: Forty-eight patients were considered, twenty-seven women and twenty-one men, with pain relief or collectively determined by a known joint synovial disease, who underwent MRI at our institution between 2000 and the second half of 2010. All patients underwent magnetic resonance imaging using a low field magnet (0.2 Tesla) or high field magnet (1,5Tesla). RESULTS: Only nine patients were diagnosed with an inflammatory arthropathy, in the remaining cases non-inflammatory arthropathy of which the most frequent form was pigmented villonodular synovitis (PVNS) was diagnosed. CONCLUSIONS: MRI is able to provide an accurate representation of all the pathological changes involved in the joint space following acute or chronic inflammation and to define the characteristic features useful in differential diagnosis.

Malignant tumours of the small intestine: a review of histopathology, multidetector CT and MRI aspects.

Small bowel neoplasms, including adenocarcinoma, carcinoid tumour, lymphoma and gastrointestinal stromal tumours, represent a small percentage of gastrointestinal cancers, yet are among those with the poorest prognosis compared with other gastrointestinal malignancies. Unclear clinical scenarios and difficult radiological diagnosis often delay treatment with negative effects on patient survival. Recently, multidetector CT (MDCT) and MRI have been introduced as feasible and accurate diagnostic techniques for the identification and staging of small bowel neoplasms. These techniques are gradually replacing conventional barium radiography as the tool of choice. However, the inherent technical and physiological challenges of small bowel imaging require a familiarity with patient preparation and scan protocols. Adequate knowledge of the histopathology and natural evolution of small bowel neoplasms is also important for differential diagnosis. The aim of this article is to review MDCT and MRI protocols for the evaluation of small bowel tumours and to provide a concise yet comprehensive guide to the most relevant imaging features relative to histopathology.

Clinical application of dual-source CT in the evaluation of patients with lung cancer: correlation with perfusion scintigraphy and pulmonary function tests.

PURPOSE: This study was done to assess the diagnostic potential of dual-source computed tomography (DSCT) in the functional evaluation of lung cancer patients undergoing surgical resection. The CT data were compared with pulmonary perfusion scintigraphy and pulmonary function tests (PFTs). MATERIALS AND METHODS: All patients were evaluated with DSCT, scintigraphy and PFTs. The DSCT scan protocol was as follows: two tubes (80 and 140 kV; Care Dose protocol); 70 cc of contrast material (5 cc/s); 5- to 6-s scan time; 0.6 mm collimation. After the automatic calculation of lung perfusion with DSCT and quantification of air volumes and emphysema with dedicated software applications, the perfusional CT studies were compared with scintigraphy using a visual score for perfusion defects; CT air volumes and emphysema were compared with PFTs. RESULTS: The values of accuracy, sensitivity, specificity and positive (PPV) and negative (NPV) predictive values of DSCT compared with perfusion scintigraphy as the reference standard were: 0.88, 0.84, 0.90, 0.93 and 0.88, respectively. The McNemar test did not identify significant differences either between the two imaging techniques (p=0.07) or between CT and PFTs (p=0.09). CONCLUSIONS: DSCT is a robust and promising technique that provides important and accurate information on lung function.

Incidental enhancing lesions found on preoperative breast MRI: management and role of second-look ultrasound.

PURPOSE: This study prospectively assessed second-look ultrasound (US) for the evaluation of incidental enhancing lesions identified on preoperative breast magnetic resonance imaging (MRI). MATERIALS AND METHODS: Between 2004 and 2007, 182 patients with malignant breast lesions detected on US and/or X-ray mammography and confirmed by cytology/histology underwent preoperative breast contrast-enhanced (CE)-MRI. Patients with incidental lesions on breast MRI underwent second-look high-resolution US directed at the site of the incidental finding. Diagnosis of incidental lesions was based on biopsy or 24-month follow-up. RESULTS: Breast MRI detected 55 additional lesions in 46/182 (25.2%) patients. Forty-two of 55 (76.3%) lesions were detected on second-look US in 38/46 (82.6%) patients. Malignancy was confirmed for 24/42 (57.1%) correlate lesions compared with 7/13 (53.8%) noncorrelate lesions. Second-look US depicted 8/9 (88.8%) Breast Imaging Reporting and Data System (BI-RADS) 5, 16/22 (72.7%) BI-RADS 4 and 18/24 (75%) BI-RADS 3 lesions. Sensitivity, specificity, accuracy and positive and negative predictive values for lesion detection/diagnosis was 100%, 88.9%, 94.6%, 90.3% and 100% for MRI and 64.3%, 70.4%, 67.3%, 69.2% and 65.5% for second-look US. Improved performance for US was obtained when masslike lesions only were considered. CONCLUSIONS: Second-look US is a confirmatory method for incidental findings on breast MRI, particularly for mass-like lesions.

Utility of T2-weighted short-tau inversion recovery (STIR) sequences in cardiac MRI: an overview of clinical applications in ischaemic and non-ischaemic heart disease.

T2-weighted short-tau inversion recovery (T2w-STIR) imaging is the best approach for oedema-weighted cardiac magnetic resonance imaging (MRI), as it suppresses the signal from flowing blood and from fat and enhances sensitivity to tissue fluid. The purpose of this pictorial review is to illustrate the clinical use and application of this technique in various ischaemic and non-ischaemic conditions. In ischaemic heart disease, T2w-STIR represents the technique of choice for detecting oedema in patients with acute myocardial infarction (MI), allowing discrimination of acute and chronic injuries. Myocardial haemorrhage may also be depicted as a region of signal abnormality characterised by a central hypointense core with a peripheral hyperintense rim, presumably reflecting the presence of intracellular methaemoglobin within the necrotic area. In the acute setting, elevated T2 relaxation times in association with regional contractile dysfunction but no signs of delayed enhancement may also signify a reversible ischaemic injury without necrosis. In acute myocarditis, the distribution pattern of T2w hyperintensity may be focal in approximately 30% of patients or diffuse in the remaining 70%, and myocardial oedema may be the only marker of disease. Tissue oedema may also be observed in various other conditions, such as primary cardiomyopathies (CMP), storage disease, pulmonary hypertension and cardiac transplant rejection. T2w-STIR represents an appealing and versatile technique that can be applied in a wide variety of ischaemic and non-ischaemic conditions, allowing detection of segmental or global increase of myocardial free water content, reflecting an acute myocardial injury.

Quantitative ultrasound of the phalanges and DXA of the lumbar spine and proximal femur in evaluating the risk of osteoporotic vertebral fracture in postmenopausal women.

PURPOSE: This study was undertaken to compare the quantitative ultrasound (QUS) parameters of amplitude-dependent speed of sound (AD-SoS) and ultrasound bone profile index (UBPI) of the phalanges with bone mineral density (BMD) of the lumbar spine and proximal hip using dual-energy X-ray absorptiometry (DXA) in discriminating women with vertebral fracture. MATERIALS AND METHODS: A total of 692 postmenopausal Caucasian women were included in the study. The presence of vertebral fracture was evaluated by radiography. AD-SoS and UBPI were measured at the phalangeal metaphysis using a DBM Sonic device. Multiple logistic regression analysis was performed to estimate the odds ratio (OR) for vertebral fractures. The ORs were also adjusted for the significant anthropometric variables of age, weight and height. Furthermore, for QUS parameters, the ORs were also adjusted for lumbar spine and total hip BMD. RESULTS: All measurements obtained with DXA and QUS significantly discriminated between women with and without fractures (p<0.0001). However, the OR was higher for lumbar spine BMD (OR 4.01), AD-SoS (OR 3.81), total hip (OR 3.7) and femoral neck BMD (OR 3.62). CONCLUSIONS: The QUS parameter AD-SoS showed diagnostic sensitivity equal to that of lumbar DXA in discriminating between women with and without osteoporotic vertebral fractures.

Prospective comparative analysis of colour-Doppler ultrasound, contrast-enhanced ultrasound, computed tomography and magnetic resonance in detecting endoleak after endovascular abdominal aortic aneurysm repair.

OBJECTIVES: To assess the accuracy of colour-Doppler ultrasound (CDUS), contrast-enhanced ultrasonography (CEUS), computed tomography angiography (CTA) and magnetic resonance angiography (MRA) in detecting endoleaks after endovascular abdominal aortic aneurysm repair (EVAR). DESIGN: Prospective, observational study. MATERIALS AND METHODS: From December 2007 to April 2009, 108 consecutive patients who underwent EVAR were evaluated with CDUS, CEUS, CTA and MRA as well as angiography, if further treatment was necessary. Sensitivity, specificity, accuracy and negative predictive value of ultrasound examinations were compared with CTA and MRA as the reference standards, or with angiography when available. RESULTS: Twenty-four endoleaks (22%, type II: 22 cases, type III: two cases) were documented. Sensitivity and specificity of CDUS, CEUS, CTA, and MRA were 58% and 93%, 96% and 100%, 83% and 100% and 96% and 100% respectively. CEUS allowed better classification of endoleaks in 10, two and one patients compared with CDUS, CTA and MRA, respectively. CONCLUSIONS: The accuracy of CEUS in detecting endoleaks after EVAR is markedly better than CDUS and is similar to CTA and MRA. CEUS seems to be a feasible tool in the long-term surveillance after EVAR, and it may better classify endoleaks missed by other imaging techniques.

Role of magnetic resonance spectroscopic imaging ([¹H]MRSI) and dynamic contrast-enhanced MRI (DCE-MRI) in identifying prostate cancer foci in patients with negative biopsy and high levels of prostate-specific antigen (PSA).

PURPOSE: The purpose of this study was to evaluate the role of magnetic resonance spectroscopic imaging (MRSI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in detecting tumour foci in patients with elevated prostate-specific antigen (PSA) and negative transrectal ultrasonography (TRUS)-guided biopsy. MATERIALS AND METHODS: This prospective randomised trial was conducted on 150 patients who underwent [¹H]MRSI and DCE-MRI and targeted biopsies of suspicious areas on MRI associated with random biopsies. RESULTS: After the second biopsy, the diagnosis of prostate adenocarcinoma was made in 64/150 cases. On a per-patient basis, MRSI had 82.8% sensitivity, 91.8% specificity, 88.3% positive predictive value (PPV), 87.8% negative predictive value (NPV) and 85.7% diagnostic accuracy. The sensitivity, specificity, PPV, NPV and accuracy for DCE-MRI was 76.5%, 89.5%, 84.5%, 83.7% and 82%, respectively. The combination of MRSI and DCE-MRI yielded 93.7% sensitivity, 90.7% specificity, 88.2% PPV, 95.1% NPV and 90.9% accuracy in detecting prostate carcinoma. CONCLUSIONS: The combined study with [¹H]MRSI and DCE-MRI showed promising results in guiding the biopsy of cancer foci in patients with an initial negative TRUS-guided biopsy.

Is pattern III as evidenced by US color-Doppler useful in predicting thyroid nodule malignancy? Large-scale retrospective analysis.

OBJECTIVE: To evaluate whether pattern III of color Doppler Ultra-sound may identify malignant nodules. MATERIALS AND METHODS: We have retrospectively analyzed data pertaining to 1090 patients of both genders (230 males, 860 females), with an average age of 53 years (min 17 years, max 81 years), who underwent thyroidectomy in Department of Surgical Sciences of Sapienza University of Rome since January 2003 through June 2009. We correlated color-Doppler characteristics and histological features through statistical analysis so as to verify statistical correlation between them. RESULTS: Our study showed that 164/273 (60.1%) patients with malignant disease were associated with vascularization pattern III. Regarding benign disease, 152/268 (56.7%) patients showed a pattern of vascularization 3 at ultrasonography. The statistical analysis was not able to show any correlation between pattern III and malignancy. CONCLUSION: Pattern III cannot be used to predict malignancy with confidence, and FNA is still mandatory to rule out the nature of the nodule.

Detection of hepatic metastases from colorectal cancer: prospective evaluation of gray scale US versus SonoVue® low mechanical index real time-enhanced US as compared with multidetector-CT or Gd-BOPTA-MRI.

PURPOSE: To compare ultrasound (US), low-mechanical index contrast enhanced US (CEUS) and multidetector-CT (MDCT) for the detection of hepatic metastases from colorectal cancer. METHODS AND MATERIALS: From January to June 2006, 110 patients (65 males, 45 females; mean age 62 years; range 39-78) with suspected hepatic lesions from colorectal cancer were prospectively evaluated with US, CEUS and MDCT by two independent readers. Intraoperative ultrasonography (IOUS, n = 45) or a follow-up up for at least 6 months by using MDCT or Gd-BOPTA-enhanced MRI was considered the gold standard. McNemar test was employed. RESULTS: Reference standards revealed 430 metastases in 110 patients. On a patient-by-patients analysis, CEUS improved US sensitivity from 67.4-71.6% to 93.4-95.8% (p < 0.05). On a lesion-by-lesion analysis, CEUS improved the sensitivity of US from 60.9-64.9% to 85.3-92.8% (p < 0.001). The specificity increased from 50-60% to 76.7-83.3%. No significant differences in sensitivity or specificity between CEUS and MDCT were found. Contrast-enhanced US was significantly more sensitive than baseline US in the detection of metastases smaller than 1 cm (p < 0.001) with an increase in sensitivity from 29.1-35% to 63.3-76.6% no significant statistical difference was identified when compared with MDCT (sensitivity of 73.3-75.8%). CONCLUSIONS: CEUS is significantly more accurate than US and highly comparable with MDCT in the detection of liver metastases from colorectal cancer. Therefore, in the evaluation of patients with suspected hepatic metastases from colorectal tumour, US examination must be performed after contrast administration.

Morpho-functional patterns of physiologic oropharyngeal swallowing evaluated with dynamic fast MRI.

With the advent of dynamic fast MRI sequences the act of deglutition can be dynamically visualized in cine-mode. Twenty-three healthy volunteers were enrolled in this study to define the morpho-functional patterns of oral and pharyngeal deglutition using new dynamic MRI techniques. All subjects were previously submitted to video endoscopic assessment, to exclude swallowing abnormalities. As contrast material a combination of yogurt mixed with gadolinium-diethylene diamine pentaacetic acid was used. The protocol was divided into three parts: (a) preliminary assessment of the oral cavity, pharynx and laryngeal structures; (b) morphologic assessment of tongue, soft palate, pharynx, epiglottis and larynx-hyoid bone; (c) dynamic assessment of swallowing without administrating any contrast media and, in subsequent phase, by injecting 5 ml of yogurt-based contrast medium in the patient's mouth. The time resolution was 3-4 images/s. The MR protocol revealed to be effective in the evaluation of normal motility patterns of the structures involved in swallowing. Moreover, the evaluation of the bolus progression, slowdown or stagnation, was possible. On the contrary problems were encountered in calculating precisely the bolus progression time, because of the insufficient temporal resolution. However, more energy should be invested to optimize the spatial and temporal resolution of turbo-FLASH sequences, to obtain a better dynamic representation of a complex function such as deglutition.

Diagnostic accuracy of translucency rendering to differentiate polyps from pseudopolyps at 3D endoluminal CT colonography: a feasibility study.

PURPOSE: The aim of this study was to assess the accuracy of translucency rendering (TR) in computed tomographic (CT) colonography without cathartic preparation using primary 3D reading. MATERIALS AND METHODS: From 350 patients with 482 endoscopically verified polyps, 50 pathologically proven polyps and 50 pseudopolyps were retrospectively examined. For faecal tagging, all patients ingested 140 ml of orally administered iodinated contrast agent (diatrizoate meglumine and diatrizoate sodium) at meals 48 h prior to CT colonography examination and two h prior to scanning. CT colonography was performed using a 64-section CT scanner. Colonoscopy with segmental unblinding was performed within 2 weeks after CT. Three independent radiologists retrospectively evaluated TRCT clonographic images using a dedicated software package (V3D-Colon System). To enable size-dependent statistical analysis, lesions were stratified into the following size categories: small (< or =5 mm), intermediate (6-9 mm), and large (> or =10 mm). RESULTS: Overall average TR sensitivity for polyp characterisation was 96.6%, and overall average specificity for pseudopolyp characterisation was 91.3%. Overall average diagnostic accuracy (area under the curve) of TR for characterising colonic lesions was 0.97. CONCLUSIONS: TR is an accurate tool that facilitates interpretation of images obtained with a primary 3D analysis, thus enabling easy differentiation of polyps from pseudopolyps.

Preliminary experience with MRA in evaluating the degree of carotid stenosis and plaque morphology using high-resolution sequences after gadofosveset trisodium (Vasovist) administration: comparison with CTA and DSA.

PURPOSE: The authors performed a preliminary study with blood-pool contrast-enhanced magnetic resonance angiography (MRA) in evaluating the degree of carotid artery stenosis and plaque morphology, comparing the diagnostic performance of first-pass (FP) and steady-state (SS) acquisitions with 64-slice computed tomography angiography (CTA) and using digital subtraction angiography (DSA) as the reference standard. MATERIALS AND METHODS: Twenty patients with >or=50% carotid artery stenosis at Doppler sonography underwent blood-pool contrast-enhanced MRA, CTA and DSA. Two independent radiologists evaluated MRA and CTA examinations to assess the degree of stenosis and characterise plaque morphology. Accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for FP, SS and CTA. The McNemar and Wilcoxon tests were used to determine significant differences (p<0.05) between the diagnostic performance of the three modalities. RESULTS: Forty carotid bifurcations were studied. For stenosis grading, accuracy, sensitivity, specificity, PPV and NPV were 90%, 89%, 90%, 89% and 90%, respectively, at FP; 95%, 95%, 95%, 95% and 95%, respectively, at SS; and 97.5%, 95%, 100%, 100% and 95%, respectively, at CTA. SS and CTA were superior to FP for evaluating the degree of stenosis (p<0.05). For evaluating plaque morphology, accuracy, sensitivity, specificity, PPV and NPV were 87.5%, 89%, 86%, 85% and 90%, respectively, at FP; 97.5%, 100%, 95%, 95% and 100%, respectively, at SS; and 100%, 100%, 100%, 100% and 100%, respectively, at CTA. There were no significant differences between FP, SS and CTA for plaque assessment (p>0.05). CONCLUSIONS: Blood-pool contrast-enhanced MRA with SS sequences allow improved diagnostic evaluation of the degree of carotid stenosis and plaque morphology compared with FP and is substantially equal to CTA and DSA.

CAD (computed-aided detection) and CADx (computer aided diagnosis) systems in identifying and characterising lung nodules on chest CT: overview of research, developments and new prospects.

Computer-aided detection (CAD) systems allow the automatic identification of lung nodules on chest computed tomography (CT), providing a second opinion to the radiologist's judgement and a volumetric evaluation of lesions - a very important aspect in oncological patients. The natural evolution of these systems has led to the introduction of computer-aided diagnosis (CADx) systems, which are able not only to identify nodules but also to characterise them by determining a likelihood of malignancy or benignity. The aim of this article is to describe the main technical principles of CAD and CADx systems, their applicability and influence in clinical practice and new prospects for their future development.

Chlamydophila pneumoniae infection in patients undergoing carotid artery stent.

Although several reports have correlated Chlamydophila pneumoniae (CP) infection with carotid endarterectomy and coronary stent, no data have been reported on the potential relationship between this pathogen and carotid artery stenting (CAS). Hence, we evaluated 47 subjects, 27 symptomatic and 20 asymptomatic, before CAS intervention and during the follow up, for the presence of CP DNA and anti-CP antibodies, including chlamydial HSP60 (Cp-HSP60). Before stent placement, CP DNA was detected exclusively in symptomatic patients, all of whom were also positive for CP IgG and IgA and 85.7 percent of them also had CP-HSP60 antibodies. At the follow-up, all CP DNA positive and 11 out of the 13 symptomatic patients with Cp-HSP60 antibodies became negatives. In contrast, no change was observed for CP- IgA antibodies. Despite the small number of patients, the present study advocates an important role of CP infection in symptomatic patients with carotid artery disease. Our findings also suggest that stent placement and/or therapy might have a role in favouring resolution of inflammation, though not affecting persistence of CP infection.

Diagnostic performance of 64-MDCT and 1.5-T MRI with high-resolution sequences in the T staging of gastric cancer: a comparative analysis with histopathology.

PURPOSE: This study was undertaken to compare the accuracy of magnetic resonance (MR) imaging and 64-slice multidetector computed tomography (64-MDCT) in the T staging of gastric carcinoma in comparison with histopathology. MATERIALS AND METHODS: Forty patients with an endoscopic diagnosis of gastric carcinoma underwent preoperative MR imaging and 64-MDCT, both of which were performed after i.v. injection of scopolamine and water distension of the stomach. In the MR imaging protocol, we acquired T2-weighted turbo spin-echo (TSE) sequences, true fast imaging steady-state free precession (true-FISP) and gadolinium-enhanced T1-weighted volumetric interpolated breath-hold examination (VIBE) 3D sequences. Contrastenhanced CT scans were obtained in the arterial and venous phases. Two groups of radiologists independently reviewed the MR and 64-MDCT images. The results were compared with pathology findings. RESULTS: In the evaluation of T stage, 64-MDCT had 82.5% and MR imaging had 80% sensitivity. Accuracy of MR imaging was slightly higher than that of 64-MDCT in identifying T1 lesions (50% vs 37.5%), whereas the accuracy of 64-MDCT was higher in differentiating T2 lesions (81.2% vs 68.7%). The accuracy of MR imaging and 64-MDCT did not differ significantly in the evaluation of T3-T4 lesions (p>0.05). Understaging was observed in 20% of cases with MR imaging and in 17.5% with 64-MDCT. CONCLUSIONS: MR imaging and 64-MDCT accuracy levels did not differ in advanced stages of disease, whereas MR imaging was superior in identifying early stages of gastric cancer and can be considered a valid alternative to MDCT in clinical practice.