DTI metrics reflecting microstructural changes of normal appearing deep grey matter in multiple sclerosis

Purpose: To evaluate the role of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) in detecting microstructural changes of normal-appearing deep grey matter (NDGM) in multiple sclerosis (MS). Patient and methods: We examined 40 patients with MS and 20 healthy volunteers using DTI to correlate average ADC and FA of the thalami, lentiform and caudate nuclei between the two groups. Receiver operating characteristic analysis was used to test the diagnostic performance of ADC and FA in detecting NDGM involvement in multiple sclerosis. Results: Between the two study groups, there was statistically significant difference of ADC of thalami, lentiform, caudate nuclei, and FA of the thalami (p < .05). No statistically significant difference of FA of lentiform (p = .2) and caudate (p = .06) nuclei. For detection of microstructural changes of NDGM, ADC cut off values were 0.762 × 10−3 mm2/s for thalamus (90% sensitivity and 66% specificity), 0.529 × 10−3 mm2/s for lentiform (86% sensitivity and 60% specificity) and 0.784 × 10−3 mm2/s for caudate nuclei (83% sensitivity and 67% specificity). Conclusion: ADC has better diagnostic performance and is more accurate than FA as a measure to detect microstructural changes of NDGM

The coronary arterial anatomy of the 17-segment model using 3-Tesla cardiac magnetic resonance imaging

AbstractAimTo analyze the correspondence of the 17 left ventricular myocardial segments with each coronary artery by using late gadolinium contrast enhanced cardiovascular magnetic resonance (CMR) imaging.Material and methodsA total number of 58 patients with known or suspected ischemic heart disease were enrolled in this study. Those patients were scheduled for CMR and conventional coronary angiography. The correspondence between the coronary artery distribution and the supplied myocardium was assessed according to the 17-segment model.ResultsThe segments 1, 2, 3, 7, 8, 13, 14 and 17 were totally specific for LAD, segments 6 and 12 were totally specific for LCX, and segment 10 was specific for RCA. There was overlap between LAD and RCA for segments 9 and 15. There was overlap between LCX and RCA for segments 4, 5 and 11. The segment 16 was shared by the all territories (LAD, LCX and RCA) with slight LCX predominance.ConclusionsOur study concluded that the LAD territory on CMR bases is larger than the American Heart Association (AHA) proposed 17-segment model

Role of 3-T diffusion-weighted magnetic resonance imaging in differentiation between benign and malignant hepatic lesions

Aim: To evaluate the ability of DWIs to distinguish between benign and malignant focal hepatic lesions (FHLs) using 3 T MR. Material and methods: A total of 73 FHLs in 48 patients were evaluated. There were 28 benign lesions including 13 hemangiomas (17.8%), 8 hepatic cysts (10.9%), 4 regenerating hepatic nodules (5.4%), 2 adenomas (2.7%) and 1 focal fatty infiltration (1.3%). The others 45 lesions were malignant including 28 hepatocellular carcinomas (38.3%), 15 metastases (20.5%) and 2 cholangiocarcinomas (2.7%). The study used two b values (0 and 800 s/mm2) and the ADC values were calculated. Results: The mean ADC value for simple liver cysts was 2.58 ± 0.35 × 10−3 mm2/s, for solid benign lesions was 1.63 ± 0.41 × 10−3 mm2/s and for malignant lesions was 1.21 ± 0.38 × 10−3 mm2/s with statistical difference (p < 0.0001). We found that the best ADC cutoff value was 1.49 × 10−3 mm2/s with accuracy of 83.6% in differentiation between the all benign and malignant FHLs. While with exclusion of the cystic hepatic lesions, the best ADC cutoff value was reduced to be 1.35 × 10−3 mm2/s with accuracy of 78.5%. Conclusions: DWI can be used to differentiate between the benign and malignant FHLs

Cardiac MR-assessed hemodynamic changes in pulmonary arterial hypertension and their relation to pulmonary artery pressure

Purpose: To demonstrate the hemodynamic changes of pulmonary arterial hypertension using cardiac MRI and to determine which parameters are best representative of the pulmonary artery pressure. Patient and methods: We examined 44 patients with pulmonary arterial hypertension using cine cardiac imaging and phase-contrast velocity encoding sequence to obtain data regarding ventricular morphology, function and pulmonary artery flow. The resulting parameters were correlated to echocardiography-derived mean pulmonary artery pressure. Results: We found increased right ventricular end diastolic, end systolic volumes and mass with decreased stroke volume and ejection fraction. The left ventricular end diastolic volume and stroke volume decreased and the end systolic volume increased while the ventricular mass index has increased compared to normal populations. The mean pulmonary artery pressure had significant positive correlation with the ventricular mass index (r = 0.61; p = 0.02) and right ventricular mass (r = 0.40; p = 0.02) with significant negative correlation with right ventricular ejection fraction (r = −0.48; p = 0009). Conclusion: MR-derived ventricular mass index, right ventricular mass, and right ventricular ejection fraction had the strongest relation with the pulmonary artery pressure, and hence they could be reliable parameters on monitoring patients with pulmonary arterial hypertension

Evaluation of left ventricle diastolic dysfunction in ischemic heart disease by CMR: Correlation with echocardiography and myocardial scarring

Objective: To detect the value of cardiac MR imaging in assessment of left ventricle diastolic function in patients with ischemic heart disease compared to echocardiography and to correlate the degree of dysfunction to the extent of myocardial scarring. Patients and methods: We examined 40 patients with known coronary artery disease. Mean patient’s age was 48 ± 10. All patients were subjected to 2D echocardiography and CMR including transmitral flow and left atrial planimetry. The degree of diastolic dysfunction was detected and correlated with the echocardiographic results and the extent of myocardial scarring. Results: On CMR, 35% of the cases had grade I diastolic dysfunction, 35% showed grade II, 15% had grade III while 15% showed normal diastolic function. CMR showed 94.12% sensitivity, 100% specificity and 95% accuracy. Excellent agreement with echocardiography was detected (Kappa coefficient 0.931). There was a significant correlation between the degree of diastolic dysfunction and the extent of myocardial scarring with Spearman’s correlation coefficient of 0.492 and p = 0.028. Conclusion: CMR has comparative results to echocardiography in assessment of diastolic dysfunction. We found a significant correlation between the degree of diastolic dysfunction and the extent of myocardial scarring