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Objective To establish a platform by using carotid MRI and computational fluid dynamics (CFD) to assess hemodynamic changes around carotid atherosclerotic plaques. Methods Thirteen patients with carotid atherosclerosis were recruited in this study. Six volunteers were regarded as normal controls. All the patients and volunteers underwent carotid MRI and contrast-enhanced magnetic resonance angiography (CEMRA). Carotid MRI was used to visualize the plaque structures and components. All plaques were divided into different types according to plaque components. CEMRA images were used to obtain three-dimensional (3D) models of carotid bifurcations, whose boundary conditions were specified using CFD front-end software, and then the mesh file of the 3D models were obtained to import to CFD software to visualize hemodynamic maps, including wall shear stress (WSS), static pressure and blood velocity. Results Fifteen diseased internal carotid arteries (ICAs) were assessed. According to the MRI appearance of the plaques, the types of these plaques were from IV-V to VIII. All of these were vulnerable plaques which caused irregular stenosis of ICAs. The WSS, static pressure and blood velocity were (79.86 ± 57.83) Pa, (- 7586.81 ± 9313.83) Pa, (2.76±1.81) m/s, respectively in the diseased ICAs group and (2.52 ± 0.58) Pa, (- 71.65 ± 30.89) Pa, (0.21 ± 0.06) m/s, respectively in the normal control group. In the diseased ICAs group WSS was elevated heterogenously and static pressure was decreased heterogenously near the plaques. The blood velocity near the plaques was increased but still streamlined. Statistical significant differences were shown for WSS, static pressure and blood velocity between 2 groups (P = 0.000, for all). Conclusions The platform combining MRI and CFD can be used to analyze the plaque structures and fluid dynamic change near the plaques, suggesting hemodynamics plays an important role in the plaque progression and vulnerability. [ABSTRACT FROM AUTHOR]

Computed tomography perfusion (CTP) map can sensitively and accurately distinguish between infarct core and ischemic penumbra. However, CTP mapping software might not generate a perfusion map because of head movement; thus, analysing CTP source images (CTP-SI) is necessary in this situation to provide information for stroke diagnosis and therapy. In our work, 'one-stop shop' computed tomography (CT) examination including non-contrast-enhanced CT (NCCT), CTP, CT angiography (CTA) were performed in 24 patients with symptoms of acute stroke less than 9 hours. We divided patients into two groups (with and without delayed perfusion on CTP-SI), and compared the Alberta Stroke Program Early CT Score (ASPECTS) on CTP-SI and CTA-SI with follow-up imaging. Using follow-up imaging ASPECTS as the final infarct size, our results suggests that the ASPECTS of both CTP-SI and CTA-SI effectively predict final infarct core in the group without delayed perfusion, whereas CTP-SI has a potential advantage over CTA-SI in being able to predict final infarct core in the group with delayed perfusion. In conclusion, CTP-SI provides useful complementary information when CTP map software could not generate perfusion maps. [ABSTRACT FROM AUTHOR]

Objective: To study clinical and imaging features of hypothalamic hamartoma in children., Methods: Imaging findings and clinical manifestations of 38 children with hypothalamic hamartomas were retrospectively reviewed. The patients included 25 boys and 13 girls, ranging in age of onset from 1 month to 15 years. All the 38 patients were examined with pre-contrast and post-contrast T1 weighted MR imaging and with non-contrast T2 weighted MR imaging. Meanwhile, 10 patients received CT scan. Hypothalamic hamartomas were confimed by pathologic examinations in the 38 patients., Results: Gelastic epilepsy, precocious puberty, other types of epilepsy and disturbance of intelligence were main manifestations in the 38 patients. Gelastic epilepsy was found as an initial clinical symptom in 17 cases, precocious puberty in 13 cases and other types of epilepsy in 8 cases. All masses were located in the suprasellar and interpeduncular cistern. They showed iso-density on CT scan, and homogeneous signal iso-intense to gray matter on T1 and T2 weighted MR images. With contrast MR images, there was no enhancement in the mass. The size or pedunculation of the mass was not correlated with clinical features., Conclusions: Hypothalamic hamartoma may be characterized by precocious puberty and/or gelastic epilepsy and specific imaging findings mentioned above.

Objective: To study the clinical value of 1H-magnetic resonance spectroscopy (1H-MRS) in differential diagnosis of brain low-grade gliomas and demyelinating diseases., Methods: 1H-MRS was performed in 24 patients with low-grade gliomas and 22 patients with demyelinating diseases and the results were retrospectively reviewed. The metabolites including N-acetyl aspartate (NAA), choline (Cho), and creatine (Cr) were detected in different areas including lesions and the normal brain. The ratios of NAA/Cr, NAA/Cho, and Cho/Cr were also computed., Results: Compared with the normal brain tissue, low-grade gliomas and demyelinating diseases had significantly different ratios of NAA/Cr, NAA/Cho, and Cho/Cr (P < 0.05). The ratios of NAA/Cho and Cho/Cr were significantly different between low-grade gliomas and demyelinating diseases (P < 0.05), while the ratio of NAA/Cr was not significantly different (P > 0.05)., Conclusions: The ratio of NAA/Cho and Cho/Cr is remarkably different between low-grade gliomas and demyelinating diseases. It can a useful indicator for differential diagnosis of these two diseases by 1H-MRS.

Elasticity is an important physical property of human tissues. There is a tremendous difference in elasticity between normal and pathological tissues. Noninvasive evaluation of the elasticity of human tissues would be valuable for clinical practice. Magnetic resonance elastography (MRE) is a recently developed noninvasive imaging technique that can directly visualize and quantitatively measure tissue elasticity. This article reviewed the MRE technique and its current status.

Objective: To explore the role of preoperative blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) and diffusion tensor tractography (DTT) to identify the relationship between motor cortical area, pyramidal tracts with brain gliomas in neurosurgical treatment of intraoperative electrical stimulation for gliomas involving motor areas at 3T., Methods: Twenty-eight patients with brain gliomas involving motor areas were included. They underwent MRI examination, which included conventional T1WI, T2WI, BOLD-fMRI of bilateral hands movement paradigm and diffusion tensor imaging (DTI). The data of BOLD-fMRI and DTI were transferred to the workstation (Leonardo syngo 2003A, Siemens) and analyzed. Activation mapping of hands movement, fractional Anisotropy (FA) Color and three dimensional pyramidal tracts were produced. The relationship between motor cortical area, pyramidal tracts and brain gliomas was demonstrated, which was used to optimize the pre-surgical planning. With guidance of the result of BOLD-fMRI and DTT, all patients received microsurgery under anaesthesia retaining consciousness using intraoperative motor functional brain mapping with the method of direct electrical stimulations. The brain lesions were removed as far as possible in the case of eloquent areas and sub-cortical important white matters preservation. The preoperative and postoperative KPS of all patients were operated to evaluate the state of patients., Results: BOLD-fMRI, DTI were performed successfully in 28 patients. The relationship between the primary motor cortex, premotor area, supplementary motor area, pyramidal tracts and brain gliomas localized by preoperative fMRI and DTI. Under anaesthesia retaining consciousness, the primary motor area was monitored by the method of direct electrical stimulations with the guidance of preoperative BOLD-fMRI. There was good correlation between preoperative fMRI and intraoperative cortical stimulation. Furthermore, the preoperative mappings and DTT could make up for the un-monitored motor areas and pyramidal tracts during operative cortical stimulation. Comparing the preoperative KPS, the postoperative KPS was advanced., Conclusions: BOLD-fMRI and DTT could non-invasively localize the relationship between brain motor cortex, pyramidal tracts and brain gliomas in vivo to optimize the surgical planning, guide the microsurgery under anaesthesia retaining consciousness using intraoperative motor functional brain mapping with the method of direct electrical stimulations and remove brain tumors as far as possible in the case of eloquent areas and sub-cortical important white matters preservation.

Objective: To analyze the impact of hematoma location and vascular territory on the clinical symptoms and signs, neuroimaging findings, and clinical prognosis of striatocapsular hemorrhage., Methods: The data of 181 cases of striatocapsular hemorrhage, 124 males and 57 females, aged 28 - 89, including medical history, symptoms, and signs were analyzed. On the basis of hematoma locations and arterial territories, the striatocapsular hemorrhage was divided into six types: anterior type (with the blood supply from Heubner's artery), middle type (with the blood supply from medial lenticulostriate artery), posteromedial type (with the blood supply from anterior choroidal artery), posterolateral type (with the blood supply from posteromedial branches of lateral lenticulostriate artery), lateral type (with the blood supply from the most of lateral branches of lenticulostriate artery), and massive type (with the hematoma occupying the whole or greater part of striatocapsular region). The short-term clinical outcome and prognosis were evaluated by Modified Rankin Scale (MRS). The relationship between the type and outcome was analyzed., Results: There were 22 cases of anterior type, accounting for 12.15%, of which 68.18% showed an excellent outcome (MRS = 0 - 2) and only 1 case died. There were 12 cases of middle type, accounting for 6.63%, of which 6 cases (50%) showed a poor outcome (MRS = 5) but without dead case. There were 19 cases of posteromedial type (10.50%), of which 52.63% had excellent outcome (MRS = 0 - 2) without dead case. There were 19 cases of posterolateral type (18.78%), of which 76.47% were with poor outcome (MRS = 5) and 17.65% died. Accounting for 39.23%, lateral type was the most common condition, of which 38.03% patients had a poor outcome (MRS = 5) and 8.45% cases died. The incidence rate of massive type was also high (12.71%), of which 47.82% showed a poor outcome (MRS = 5) and 47.83% cases died., Conclusion: Hematoma location and vascular territory are the determinating factors of prognosis of striatocapsular hemorrhage. The six-type classification system provides a simple and reliable means to predict the clinical outcomes and to guide therapeutic options of striatocapsular hemorrhage.