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ABSTRACT: To investigate the relationship between plaque compositions and stenosis patterns in patients with atherosclerotic plaques at the carotid bifurcation using magnetic resonance (MR) imaging.
One hundred and four carotid arteries with stenosis over 50% from 75 symptomatic stroke patients (64 male and 11 female; mean age 58·2±13·3 years) were studied. Plaque compositions were analyzed by high-resolution MR imaging using a 3·0T MR with a surface coil. Stenosis patterns were classified into three types according to contrast-enhanced MR angiography images. Correlations of different components of plaques and stenosis patterns were analyzed.
One hundred and four carotid arteries were analyzed. Three stenosis patterns were identified. The prevalences of the three patterns are as follows: type I (total occlusion) at 27·9% (29/104), type II (local plaque with normal distant flow) at 56·7% (59/104), and type III (local plaque with impaired distant flow) at 15·4% (16/104). The contingency coefficients between stenosis pattern and stability, intraplaque hemorrhage (IPH), lipid necrotic core (LNC), and ulcer were 0·383 (P = 0·000), 0·290 (P = 0·008), 0·439 (P = 0·000), and 0·388 (P = 0·000), respectively. Multinomial analysis showed that compared with type III vessels, type I vessels were more likely to contain IPH (P = 0·019) and less likely to contain large LNC (P = 0·001); type II vessels had a greater possibility for containing IPH than type III vessels (P = 0·009); LNC was more likely to be found in type II than in type I vessels (P = 0·000). No significant difference was found in ulceration prevalence between type II and type III vessels (P = 0·058).
The current study demonstrated positive associations between stenosis patterns and plaque compositions.
Neurological Research 05/2012; 34(4):366-72. · 1.52 Impact Factor
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ABSTRACT: Cerebral microbleeds (CMBs) detected by gradient-echo MRI have been proven to be a potential risk factor for further bleeding, while the association between CMBs and the first onset of intracerebral hemorrhage has not been well investigated.
To analyze the association between CMBs and the first onset of primary intracerebral hemorrhage (pICH).
Two hundred and two consecutive inpatients with ICH and 234 consecutive outpatients without ICH as control group were enrolled in this study. MR imaging including T2*-GRE, T(1)W, T(2)W and fluid attenuated inversion recovery (FLAIR) sequences were performed to detect CMBs and other abnormalities. Prevalence, distribution, and grades of CMBs, as well as the location and size of the intracerebral hematoma were analyzed, respectively. Comparison was made between pICH and control group. Logistic analysis was performed to evaluate the association between CMBs and ICH. The correlation between hematoma size and CMBs grade/numbers was analyzed.
CMBs were detected in 140 patients in pICH (69.3%) group and 62 patients in control group (26.5%). The incidence of CMBs in pICH group was significantly higher than that in control group (P < 0.0001). As the logistic regression analysis results, CMBs was the risk factor associated with ICH, with modulation OR value of 8.363 (95% CI 5.210-13.421). The volume of ICH with CMBs was 12.57 ± 17.23 mL, and the volume of ICH without CMBs was 17.77 ± 26.97 mL. Negative correlation was demonstrated between CMBs number and ICH volume (r(s) = -0.1769, P = 0.0118), as well as between CMBs grade and hematoma volume (r(s) = -0.1185, P = 0.1557).
CMBs may be an independent risk factor for the first onset of intracerebral hemorrhage.
Acta Radiologica 12/2011; 53(2):203-7. · 1.37 Impact Factor
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Na Li,
Yilong Wang,
Wenjuan Wang,
Li Ma,
Jing Xue,
Karin Weissenborn,
Reinhard Dengler,
Hans Worthmann,
David Z Wang, Peiyi Gao,
Liping Liu,
Yongjun Wang,
Xingquan Zhao
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ABSTRACT: Several retrospective studies suggested that contrast extravasation on CT angiography predicts hematoma expansion, poor outcome, and mortality in primary intracerebral hemorrhage. We aimed to determine the predictive value of contrast extravasation on multidetector CT angiography for clinical outcome in a prospective study.
In 160 consecutive patients with spontaneous intracerebral hemorrhage admitted within 6 hours of symptom onset, noncontrast CT and multidetector CT angiography were performed on admission. A follow-up noncontrast CT was done at 24 hours. Multidetector CT angiography images were analyzed to identify the presence of contrast extravasation. Clinical outcome was assessed by modified Rankin Scale on discharge and at 90 days.
A total of 139 patients with primary intracerebral hemorrhage were included in the final analysis. Contrast extravasation occurred in 30 (21.6%) patients. The presence of contrast extravasation was associated with increased hematoma expansion (P<0.0001), in-hospital mortality (P=0.008), prolonged hospital stay (P=0.006), poor outcome on discharge (P=0.025), increased 3-month mortality (P=0.009), and poor clinical outcome (P<0.0001). In multivariate analysis, contrast extravasation was a promising independent predictor (OR, 10.5; 95% CI, 3.2-34.7; P<0.0001) for 90-day poor clinical outcome followed by the presence of intraventricular hemorrhage (OR, 3.4; 95% CI, 1.5-7.7; P=0.003) and initial hematoma volume (OR, 1.0; 95% CI, 1.0-1.1; P=0.013).
The presence of contrast extravasation on multidetector CT angiography in patients with hyperacute-stage intracerebral hemorrhage is an independent and strong factor associated with poor outcome. Any patient with intracerebral hemorrhage with such sign on multidetector CT angiography should be monitored intensely and treated accordingly.
Stroke 12/2011; 42(12):3441-6. · 5.73 Impact Factor
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ABSTRACT: To study the multi-slice spiral computed tomography (MSCT) manifestations of gastrointestinal tract (GIT) and mesenteric tumor and tumor-like lesions in children and correlation with pathologic findings. 22 patients (17 male, 5 female; age ranged from 3 days to 11 years; with mean of 4.2 years) were screened out by ultrasonography (US) at first, then were performed with abdominal non-enhanced CT (NECT) and contrast-enhanced CT (CECT) scans. All CT images were evaluated independently by two radiologists and a consensus was reached regarding the morphologic features for lesions such as size, solid/cyst, unilocular/multilocular and thin/thick wall characteristics. The 26 lesions were categorized into two groups based on CT characteristics of lesions' nature, group 1 with the prominent cystic lesions, group 2 with prominent solid lesions. Group 1 was further divided into two subgroups: group 1A for the cystic lesions with thin walls, and group 1B for the cystic lesions with thick walls. In group 1A, 7 lesions were unilocular cysts (6 lymphangioma, 1 ileum mesenteric cyst) and 5 were multilocular cysts with internal septation (4 lymphangioma, 1 greater omental cyst). In group 1B, 10 lesions in 7 patients were unilocular without internal septation, which had two kinds of shape-cystic and tubular, their histopathological types were all enteric duplication cyst (10 segments, with two patients with 2 or 3 segments each); In group 2, all lesions had solid mass (2 gastrointestinal stromal tumors and 2 enteric non-Hodgkin's lymphoma). The majority of gastrointestinal tumors and tumor-like lesions are cystic and benign. MSCT manifestations of cystic/solid and thin/thick wall may be great helpful for differentiating different types of GIT and mesenteric lesions. MSCT manifestations have close correlations with their topographic sites and histopathologic findings.
European journal of radiology 09/2010; 75(3):293-300. · 2.65 Impact Factor
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The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques 09/2010; 37(5):697-9. · 0.97 Impact Factor
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Yilong Wang,
Xiaoling Liao,
Xingquan Zhao,
Chunxue Wang,
Liping Liu,
Yong Zhou,
Chunjuan Wang,
Jing Xue, Peiyi Gao,
Kehui Dong,
Xunming Ji,
Yongjun Wang
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ABSTRACT: BACKGROUND: Intravenous (i.v.) recombinant tissue plasminogen activator (rtPA) remains the only approved therapy for acute ischemic stroke. However, the use of i.v. thrombolysis is restricted to a minority of patients by the rigid 3-h time window. Modern imaging-based selection algorithms that can identify penumbra have been proposed as methods to extend the window and to select patients more likely to respond favorably or unfavorably to i.v. thrombolysis. AIMS: We aim to compare the safety and efficacy of multiparametric computed tomography (CT)-based i.v. thrombolysis after 3-9 h of symptom onset with standard CT-based thrombolysis within 3 h and with CT-based thrombolysis or placebo after 3-6 h from the pooled data of the large stroke rtPA trials. DESIGN: The imaging-based thrombolysis trial in acute ischemic stroke-II study is a prospective, multicenter and assessor-blind controlled study. The primary efficacy outcome will be a favorable outcome at 90 days defined as a modified Rankin Scale and reperfusion improvement 24-36 h after treatment; the primary safety end-point outcome will be intracerebral hemorrhage 24-36 h after treatment. We aim to include 200 patients by 2010. It is registered with IRCTN number: ISRCTN12033002.
International Journal of Stroke 03/2009; 4(1):49-53; discussion 49. · 2.38 Impact Factor
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ABSTRACT: The aims of this study were to analyse the distribution of cerebral microbleeds (CMBs) in patients with ischemic stroke and study the relationship between CMBs and the severity of old lacunar infarcts and cerebral white matter changes.
The study population consisted of 247 consecutive inpatients with ischemic stroke. Magnetic resonance imaging findings of these inpatients were observed. CMBs were counted respectively according to their locations, including the corticosubcortical regions, basal ganglia, thalami, brainstem and cerebellum. The number of the old lacunes and the severity of the cerebral white matter changes were also recorded. Based on the occurrence of CMBs, the patients were divided into two groups (72 patients with CMBs; 175 patients without CMBs).
The most common location of CMBs in patients with ischemic stroke was the basal ganglia, followed by the corticosubcortical region, the thalami, the brainstem and the cerebellum. The severity of CMBs was closely correlated with the severity of lacunar infarcts and cerebral white matter changes, respectively.
CMBs are closely related with cerebral microangiopathy and may be a marker of advanced stage cerebral microangiopathy.
Neurological Research 02/2009; 31(9):900-3. · 1.52 Impact Factor
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ABSTRACT: Wall shear stress (WSS) has been proved to play a critical role in formation and development of atherosclerotic plaques. Our objective was to quantify local WSS in vivo in normal subjects, and to analyze spatial distribution patterns and determine the temporal gradient of WSS. Seventy-eight CCAs of 42 healthy volunteers at common carotid arteries (CCAs) were studied. Cine phase-contrast MR sequence was used to acquire the flow velocity information. Three-dimensional paraboloid modeling was applied to fit the velocity profiles and WSS values were calculated. Mean WSS value for CCAs was 0.783+/-0.209, with the range of WSS value from -0.541 to 3.464 N/m(2). The 95% confidence interval for mean WSS value in CCA was (0.736-0.830) N/m(2). Different WSS spatial distribution patterns were classified into three types according to the location of low WSS values during a cardiac cycle. Mean value of maximum temporal gradient of WSS was 14.12+/-5.46, with the range from 5.87 to 33.23 N/m(2)s(-1). Skewed velocity profiles were displayed in most CCAs, indicating the flow patterns in CCA were more complicated than commonly assumed. Obvious inter-subject variation were found in magnitude, spatial distribution and the temporal gradient of WSS in CCAs, and the blood flow patterns as well.
Journal of Biomechanics 10/2008; 41(14):3024-30. · 2.43 Impact Factor
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ABSTRACT: The carotid bifurcation is one of the most susceptible locations for atherosclerotic plaques. It is important to assess wall shear stress (WSS) and blood flow patterns in this area.
To assess local WSS and blood flow patterns at the origin of the internal carotid artery (ICA).
Twenty-eight ICAs of 16 healthy volunteers were studied. A cine phase-contrast magnetic resonance (MR) sequence combined with a three-dimensional paraboloid model was applied to calculate WSS values and to obtain flow parameters. WSS spatial distribution features and local flow patterns were analyzed.
Mean WSS was 0.560 +/- 0.180 (range -0.745 to 3.563) N/m2 at the origin of 28 ICAs. Error points were found in six vessels. Four WSS spatial distribution patterns were classified according to the location of low WSS values. Reverse WSS was found in 20 vessels. The mean oscillatory shear index (OSI) for these vessels was 0.089 +/- 0.094 (range 1.00 x 10(-6) to 0.490). Complex flow status including reverse velocity, flow stagnancy, and high oscillating WSS was displayed in the end systole of this area.
Flow patterns were variant and complicated at the origin of the ICAs. Different types of local WSS spatial distributions were found around the vessel circumference.
Acta Radiologica 10/2008; 49(7):806-14. · 1.37 Impact Factor
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ABSTRACT: To find a better way to predict the clinical events caused by carotid vulnerable lesions via comparison study on high-resolution magnetic resonance imaging (MRI) and ultrasonography (US).
Twenty-seven symptomatic stroke patients were recruited, all of which were given both high-resolution MRI and US at bilateral carotids. Respective correlations of high-resolution MRI and US outcomes with clinical events were performed and the lesion numbers identified by high-resolution MRI and US were statistically analysed.
Six carotid arteries in six patients were excluded because of uninterpretable high-resolution MRI findings or patients' intolerance. In the remaining 48 carotids analysed, the number of carotid with vulnerable/stable lesion was 17/31 by high-resolution MRI and 25/23 by US, respectively. Contingency coefficient was 0.40 between vulnerable lesion by high-resolution MRI and clinical event (p=0.004), and 0.19 (p=0.221) by US and clinical event, respectively. The difference of detected lesion numbers between high-resolution MRI and US was statistically significant p=0.039) through matched chi-square test.
High-resolution MRI may be a better way than US in predicting the clinical events caused by carotid vulnerable lesions.
Neurological Research 06/2008; 30(4):361-5. · 1.52 Impact Factor
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ABSTRACT: The ability to rapidly and accurately evaluate the location and extent of hyperacute brain ischemia is of major clinical importance. Herein, we aimed to develop imaging criteria to classify the ischemic lesion by computed tomography (CT) perfusion (CTP) and CT angiography (CTA) in hyperacute ischemic stroke patient. Non-contrast-enhanced CT, CTP and CTA were performed in patients with symptoms of hyperacute stroke lasting <8 hours. According to the volume of infarct core, ischemic penumbra and vessel status, three ischemic lesion types were defined. Twenty-six patients were included in our study. Among them, ten patients were classified into severe group, 15 patients were classified into mild group and one patient was classified into reversible group. In acute stroke patients, the ischemic lesion typing may assist in individualizing therapeutic decisions for patients by possibly extending the window for giving thrombolytics beyond the current 3 hour limit.
Neurological Research 05/2008; 30(4):337-40. · 1.52 Impact Factor
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ABSTRACT: To determine the clinical characteristic and common etiologies of cerebral venous thrombosis (CVT) in China.
Clinical and neuroimaging data of 91 cases of CVT were analyzed retrospectively.
91 CVT patients (49 men, 42 women), aged from 9 to 57 years, were diagnosed with MRI (78 cases, 85.71%), MRA (37 cases, 40.66%) or DSA (32 cases, 35.16%). 27 cases (29.67%) had a clinical pattern of isolated intracranial hypertension, 56 cases (61.54%) of focal deficits and/or seizures, 3 cases of subacute encephalopathy and 5 cases of cavernous sinus thrombosis. Oral contraceptive was the most common cause, being found in 12 cases (13.19%).
Understanding of the clinical characteristics of CVT and using of MRI and MRA examination as early as possible is the key in CVT diagnosis. Oral contraceptive is the most common etiology.
Zhonghua nei ke za zhi [Chinese journal of internal medicine] 10/2002; 41(9):595-8.
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ABSTRACT: To investigate the findings of magnetic resonance (MR) imaging and histopathology in early postoperative normal brain, and to define the correlation between MR images and histopathology.
Thirty-six New Zealand rabbits weighing 2.0 to 3.0 kg were divided into 10 groups according to different postoperative days: 1 to 10 days. A partial resection of the parietooccipital region was performed under usual aseptic conditions after the animals were anesthetized intravenously with 3% pentobarbital (30 mg/kg). MR imaging procedures consisted of pre- and postcontrast scanning and were carried out on postoperative days 1 to 10. Brain tissue samples were prepared for examination immediately after MR scanning. Histopathological examination was done under light both and electron microscopes. The findings of MR imaging were compared with histopathologic findings.
Surgical margin contrast enhancement on MR images could be seen 24 hours after surgery. The degree of contrast enhancement increased gradually up to 5 days postoperation, and no remarkable changes were present from days 5 to 10. Disruption of the blood brain barrier (BBB) was the main cause of contrast enhancement during the first 3 postoperative days. After that period, the mechanism responsible for contrast enhancement was the formation of neovascularity and a broken BBB. An increase in the amount of neovascularity played a predominant role in contrast enhancement in normal postoperative brain tissue.
The features of enhanced MR images present at the surgical margin followed a typical time course during the early postoperative period. The role of neovascularity and BBB disruption in the formation of contrast enhancement at the surgical margin varies with time. Knowledge of the features of contrast enhancement in postoperative MR images of normal brain can help in differentiating benign changes from residual malignant glioma.
Chinese medical journal 03/2002; 115(2):247-53. · 0.86 Impact Factor
