Aortic Stiffness Is Independently Associated with Intracranial Carotid Artery Calcification in Patients with Ischemic Stroke.

INTRODUCTION: Intracranial carotid artery calcification (ICAC), as a strong contributor to the occurrence of ischemic stroke, might be present in the medial or intimal arterial layer. Traditional cardiovascular risk factors (CVRFs) are associated with ICAC; however, its association with new markers of vascular function is less understood. The paper aimed to evaluate the relationship between carotid-femoral pulse wave velocity (CF-PWV) and ICAC subtypes. METHODS: We enrolled 65 patients with ischemic stroke. CF-PWV, systolic, diastolic, mean blood pressure, and pulse pressure were measured within 6 ± 2 days after stroke onset, and CT was performed within 24 h. ICAC on the stroke site was classified by two methods: volume and score based. Tertiles of ICAC volume were determined, and low-grade ICAC (T1) was regarded as a reference. According to the score-based method, (dominant) medial and (dominant) intimal ICAC subtypes were determined. Data were analyzed with multivariate logistic regression. RESULTS: Medial and intimal ICAC subtypes were found in 34 (52%) and 24 (37%) patients, respectively. In 11% of patients, no ICAC calcifications were found. CF-PWV was higher in patients with high-grade ICAC (OR = 1.56, 95% CI = 1.03-2.35, p = 0.035). CF-PWV was higher in patients with the medial ICAC subtype (OR = 1.60, 95% CI = 1.00-2.55, p = 0.049) after adjustment for traditional CVRFs. CONCLUSION: Our study demonstrates that among patients with ischemic stroke, aortic stiffness is independently associated with ICAC and that medial ICAC, compared with intimal ICAC, is accompanied by more advanced aortic stiffness.

Assessment of the Carotid Bodies in Magnetic Resonance-A Head-to-Head Comparison with Computed Tomography.

OBJECTIVES: To evaluate carotid body visibility in contrast-enhanced magnetic resonance (MR) studies and to compare the results to contrast-enhanced computed tomography (CT). METHODS: Two observers separately evaluated MR and CT examinations of 58 patients. MR scans were acquired with contrast-enhanced isometric T1-weighted water-only Dixon sequence. CT examinations were performed 90 s after contrast agent administration. Carotid bodies' dimensions were noted and their volumes calculated. To quantify the agreement between both methods, Bland-Altman plots were computed. Receiver operating characteristic (ROC) and its localization-oriented variant (LROC) curves were plotted. RESULTS: Of the 116 expected carotid bodies, 105 were found on CT and 103 on MR at least by a single observer. Significantly more findings were concordant in CT (92.2%) than in MR (83.6%). The mean carotid body volume was smaller in CT (19.4 mm3) than in MR (20.8 mm3). The inter-observer agreement on volumes was moderately good (ICC (2,k) 0.42, p < 0.001), but with significant systematic error. The diagnostic performance of the MR method added up to 88.4% of the ROC's area under the curve and 78.0% in the LROC algorithm. CONCLUSIONS: Carotid bodies can be visualized on contrast-enhanced MR with good accuracy and inter-observer agreement. Carotid bodies assessed on MR had similar morphology as described in anatomical studies.

Vascular Abnormalities of the Parotid Region: An Uncommon Presentation of a Common Condition-A Case Series.

A variety of non-neoplastic diseases and benign and malignant lesions may involve parotid glands. In clinical practice, effective diagnosis is crucial to ensure proper treatment and achieve a good therapeutic effect. Unclear anamnesis and short medical history are factors that make diagnosis difficult, especially when cancer should be excluded. We present a case series of four patients who reported to the outpatient clinic with a unilateral nodule in the parotid region. The clinical presentation prevented an unequivocal diagnosis. The suspicion of a neoplastic disease resulted in profound diagnostics, including repeated cytology, ultrasound and magnetic resonance examination. Combining all the acquired information and follow-up, or a histopathologic examination, facilitated the final diagnosis. In all cases, thrombosis was diagnosed. We then analysed the diagnostic process and the associated difficulties. When thrombosis in vascular malformation occurs in the parotid region, it may have an unclear clinical and radiological presentation. Such an image can imitate both benign and malignant tumours. Ambiguous imaging in conjunction with blood cells in cytology should result in the inclusion of thrombosis in vascular malformations in the differential diagnosis.

Efficacy comparison of multi-phase CT and hepatotropic contrast-enhanced MRI in the differential diagnosis of focal nodular hyperplasia: a prospective cohort study.

BACKGROUND: Different clinical behaviour influences the importance of differentiating focal nodular hyperplasia (FNH) from other focal liver lesions (FLLs). The aim of this study was to compare the efficacy of contrast-enhanced CT and MRI in the diagnosis of FNH. METHODS: 157 patients with equivocal FLLs detected in ultrasonography subsequently underwent multi-phase CT and MRI with the use of hepatotropic contrast agent (Gd-BOPTA) in a 1.5 T scanner. Examinations were evaluated by three independent readers. Diagnostic efficacy of different radiological signs of FNH in both CT and MRI was compared and AFROC analysis was performed. RESULTS: 4 hepatocellular adenomas, 95 hepatocellular carcinomas, 98 hemangiomas, 138 metastases and 45 FNHs were diagnosed. In both CT and MRI the radiological sign of the highest accuracy was the presence of the central scar within FNH (0.93 and 0.96 relatively). The sum of two radiological signs in MRI: homogeneous enhancement in hepatic arterial phase (HAP) and enhancing lesion in hepatobiliary phase (HBP) was characterized with high values of sensitivity (0.89), specificity (0.97), PPV (0.82), NPV (0.98) and accuracy (0.96). After inclusion of clinical data into analysis the best discriminating feature in MRI was the presence of enhancing lesion in HBP in patients without cirrhosis. In this regard, efficacy parameters increased to 1.00, 0.99, 0.94, 1.00 and 0.99 accordingly. The area under the curve in AFROC analysis of MRI performance was significantly larger than of CT (p = 0.0145). CONCLUSION: Gd-BOPTA-enhanced MRI is a more effective method in the differential diagnosis of FNH than multi-phase CT.

Diagnostic Imaging of Hepatocellular Carcinoma - A Pictorial Essay.

Hepatocellular carcinoma (HCC) is the most common primary liver cancer, which develops mostly in the setting of chronic liver disease. European Association for the Study of the Liver (EASL) and European Organization for Research and Treatment of Cancer (EORTC) prepared guidelines for screening, follow-up and diagnosis of HCC to facilitate decision making and optimize both diagnostic and therapeutic protocols. The review briefly describes etiology, epidemiology and histopathology of HCC and presents EASL-EORTC guidelines for surveillance and diagnosis of HCC. Target population and screening algorithm is presented in the surveillance section. Ultrasound imaging of HCC and the role of contrast enhanced ultrasound are described as well as the value of laboratory tests in screening. Further, radiological features of HCC in multiphase CT and dynamic contrast enhanced MRI and diagnostic criteria are presented. Additionally, the advantages of advanced techniques in MRI such as diffusion weighed imaging and the use of hepatocyte-specific contrast agents are discussed. Lastly, the EASL-EORTC guidelines are compared with the guidelines of the American Association for the Study of Liver Diseases and the Japan Society of Hepatology. Also LI-RADS and the Barcelona Clinic Liver Cancer classification are mentioned. In the near future, due to the ongoing advances in imaging a revision of the guidelines may be expected.

Predictive value of apparent diffusion coefficient in evaluation of colorectal carcinoma hepatic metastases' response to radiofrequency ablation.

PURPOSE: To establish the apparent diffusion coefficient (ADC) suitability to evaluate the radiofrequency ablation (RFA) outcome in patients with chemotherapy resistant or partially responding colorectal adenocarcinoma liver metastases. MATERIALS AND METHODS: A total of 56 patients with 116 metastatic foci over 10 mm in diameter were examined with 1.5 Tesla MRI scanner 1 day before percutaneous RFA treatment. Lesions were evaluated in echo-planar diffusion-weighted images with b = 0, 15 and 500 s/mm(2) . On basis of computed tomography scan at 6 weeks, 3 and 6 months after RFA and serum CEA (carcinoembryonic antigen) level lesion were recognized as responding or nonresponding lesions. ADC values for b = 0-15 and 0-500 s/mm(2) of responding and nonresponding lesions were compared. RESULTS: Noncomplete ablation concerned 28 lesions. Mean pretreatment ADC values for b = 0-15 and 0-500 s/mm(2) of responding metastases were significantly lower (2.14 and 1.48 × 10(-3) mm(2) /s) than those of nonresponding tumors (2.7 and 1.74 × 10(-3) mm(2) /s). Sensitivity, specificity, and accuracy of ADC values for b = 0-15 s/mm(2) were 79 (95%CI = 59-92), 85 (95%CI = 76-92), 84%; and for b = 0-500 s/mm(2) , the efficacy parameters were, respectively, 78 (95%CI = 56-92), 78 (95%CI = 67-86), and 78%. The P value was under 0.001 for both b parameters. CONCLUSION: The pretreatment ADCs values of chemotherapy resistant or partially responding colorectal adenocarcinoma liver metastatic lesion can be predictive factor of tumors response to RFA therapy.