Publications by authors named "Mingwang Zhu"

15 Publications

  • Page 1 of 1

Automated detection of hippocampal sclerosis: Comparison of a composite MRI-based index with conventional MRI measures.

Epilepsy Res 2021 Aug 9;174:106638. Epub 2021 Apr 9.

Department of Radiology, Sanbo Brain Hospital, Capital Medical University, China. Electronic address:

Purpose: This study aims to compare the performance of an MRI-based composite index (HSI) with conventional MRI-based measures in hippocampal sclerosis (HS) detection and postoperative outcome estimation.

Methods: Seventy-two temporal lobe epilepsy (TLE) patients with pathologically confirmed HS and fifteen TLE patients without HS were included retrospectively. The T1-weighted and FLAIR images of these patients were processed with AccuBrain to quantify the hippocampal volume (HV) and the hippocampal FLAIR signal. The HSI index that considered both HV and hippocampal FLAIR signal was also calculated. Two experienced neuropathologists rated the HS severity with the resected tissue and reached an agreement for all cases. The asymmetry indices of the MRI measures were used to lateralize the sclerotic side, and the original MRI measures were applied to detect HS vs. normal hippocampi. Operating characteristic curve (ROC) analyses were performed for these predictions. We also investigated the sensitivity of the ipsilateral MRI measures in characterizing the pathological severity of HS and the associations of the MRI measures with postoperative outcomes (Engel class categories).

Results: With the optimal cutoffs, the asymmetry indices of HSI and HV both achieved excellent performance in differentiating left vs. right HS (accuracy = 100 %), and the absolute value of the asymmetry index of HSI performed best in differentiating unilateral vs. bilateral HS (accuracy = 91.7 %). Regarding the detection of HS, HSI performed better in sensitivity (94.4 % vs. 87.5 %) while HV performed better in specificity (93.6 % vs. 89.4 %) when the contralateral site of unilateral HS and both sides of non-HS patients were considered as the normal reference, and HSI performed even better than HV when only both sides of non-HS patients were considered as the normal reference (AUC: 0.956 vs. 0.934, p = 0.038). The ipsilateral HSI presented the strongest association with the pathological rating of HS severity (r = 0.405, p < 0.001). None of the ipsilateral or contralateral MRI measures was associated with the postoperative outcomes. Among the asymmetry indices, only the absolute value of the asymmetry index of HV presented a significant association with the Engel classifications for the Year 2∼3 visit (r = -0.466, p = 0.004) or the latest visit with >1 year follow-up (r = -0.374, p = 0.003) while controlling for disease duration and follow-up duration.

Conclusion: The HSI index and HV presented comparable good performance in HS detection, and HSI may have better sensitivity than HV in differentiating pathological HS severity. Higher magnitude of HV dissymmetry may indicate better post-surgical outcomes for HS patients.
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http://dx.doi.org/10.1016/j.eplepsyres.2021.106638DOI Listing
August 2021

Predictors and Long-term Outcome of Resective Epilepsy Surgery in Patients with Tuberous Sclerosis Complex: A Single-centre Retrospective Cohort Study.

Seizure 2021 May 25;88:45-52. Epub 2021 Mar 25.

Department of Neurosurgery, Center of Epilepsy, Sanbo Brain Hospital, Capital Medical University, XiangshanYikesong 50, Haidian District, Beijing 100093, China. Electronic address:

Objective: To identify prognostic factors and long-term seizure outcomes for patients with tuberous sclerosis complex (TSC) who underwent resective treatment for epilepsy.

Methods: We enrolled 81 patients with TSC who had undergone resective epilepsy surgery at Sanbo Brain Hospital, Capital Medical University, between April 2004 and June 2019. We estimated cumulative probability of remaining seizure-free and plotted survival curves. Variables were compared using Mann-Whitney U, Pearson's correlation, continuity correction, and Fisher's exact chi-square tests. Prognostic predictors were analysed using log-rank (Mantel-Cox) tests and Cox regression models.

Results: At the last follow-up, 48 (59.3%) patients were classified as International League Against Epilepsy Class 1 (including 14 patients who had seizures <3 times postoperatively on the same or different day and were seizure-free at all other times). The estimated cumulative probability of remaining seizure-free postoperatively was 69.0% (95% confidence interval [CI] 58.8-79.2%), 61.9% (95% CI 51.1-72.7%), and 55.0% (95% CI 42.8-67.2%) at 2, 5, and 10 years, respectively. The mean time of remaining seizure-free was 7.24 ± 0.634 years (95% CI 6.00-8.49); en bloc resection was an essential positive predictor of postoperative seizure freedom, as was age at seizure onset, regional interictal video-electroencephalography pattern, and temporal lobe surgery. The longer the seizure-free time, the less likely a relapse. Patients who postoperatively experienced seizures remained likely to recover.

Conclusions: We demonstrated the efficacy of surgical treatment for patients with TSC and intractable epilepsy. Detailed perioperative tests are a reliable predictor of postoperative seizure freedom.
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http://dx.doi.org/10.1016/j.seizure.2021.03.022DOI Listing
May 2021

Substitution 3A protein of foot-and-mouth disease virus of attenuated ZB strain rescued the viral replication and infection in bovine cells.

Res Vet Sci 2020 Feb 6;128:145-152. Epub 2019 Nov 6.

National Foot-and-mouth disease Para-reference Laboratory (Kunming), Yunnan Animal Science and Veterinary Institute, Kunming 650224, China; Yunnan Tropical and Subtropical Animal Virus Disease Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming 650224,China. Electronic address:

The non-structural protein 3A of foot-and-mouth disease virus (FMDV) plays an important role in viral replication, virulence and determination of host range. Previously we identified genomic changes in gene encoding 3A protein between the attenuated ZBatt strain and its parental virulent strain during the attenuation process. However, the effects of changes in 3A protein on viral replication and infection of the rabbit-attenuated ZBatt virus during the attenuation process are poorly understood. In this study, a chimeric virus, rZBatt-3A, was constructed by introducing the 3A gene of virulent ZB virus into its attenuated vaccine ZB strain. Subsequently, the biological characteristics between rZBatt-3A and its parental virus (rZBatt) were compared. The relative expression level of four host cell proteins that interact with FMDV 3A were also analyzed. The results showed that the chimeric virus rZBatt-3A exhibited significantly different growth properties and plaque phenotypes from rZBatt in primary fetal bovine kidney (BK) cells. Cytopathic effect (CPE) of the rZBatt-3A was observed in BK cells with smaller plaque size, but CPE from the rZBatt could not be observed. The viral RNA replication was higher in rZBatt-3A-infected BK cells than in rZBatt-infected cells at 24 hpi (P < .05). In addition, the relative mRNA expression level of Ubiquilin 1 (UBQLN1) was significantly increased in rZBatt-3A-infected BK cells than in rZBatt-infected cells (P < .01) suggesting that UBQLN1 may be associated with 3A protein changes. Thus, the substitution of 3A protein altered the replication efficiency of attenuated ZB virus in bovine cells. Our data suggested that changes in 3A protein might be associated with the attenuation of ZB virus, which shed more lights in molecular mechanisms about attenuation of FMDV.
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http://dx.doi.org/10.1016/j.rvsc.2019.11.001DOI Listing
February 2020

Voxel-based automated detection of focal cortical dysplasia lesions using diffusion tensor imaging and T2-weighted MRI data.

Epilepsy Behav 2018 07 21;84:127-134. Epub 2018 May 21.

Department of Radiology, Sanbo Brain Hospital, Capital Medical University, Beijing, China. Electronic address:

The aim of this study was to automatically detect focal cortical dysplasia (FCD) lesions in patients with extratemporal lobe epilepsy by relying on diffusion tensor imaging (DTI) and T2-weighted magnetic resonance imaging (MRI) data. We implemented an automated classifier using voxel-based multimodal features to identify gray and white matter abnormalities of FCD in patient cohorts. In addition to the commonly used T2-weighted image intensity feature, DTI-based features were also utilized. A Gaussian processes for machine learning (GPML) classifier was tested on 12 patients with FCD (8 with histologically confirmed FCD) scanned at 1.5 T and cross-validated using a leave-one-out strategy. Moreover, we compared the multimodal GPML paradigm's performance with that of single modal GPML and classical support vector machine (SVM). Our results demonstrated that the GPML performance on DTI-based features (mean AUC = 0.63) matches with the GPML performance on T2-weighted image intensity feature (mean AUC = 0.64). More promisingly, GPML yielded significantly improved performance (mean AUC = 0.76) when applying DTI-based features to multimodal paradigm. Based on the results, it can also be clearly stated that the proposed GPML strategy performed better and is robust to unbalanced dataset contrary to SVM that performed poorly (AUC = 0.69). Therefore, the GPML paradigm using multimodal MRI data containing DTI modality has promising result towards detection of the FCD lesions and provides an effective direction for future researches.
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http://dx.doi.org/10.1016/j.yebeh.2018.04.005DOI Listing
July 2018

Complete Genome Sequence of Foot-and-Mouth Disease Virus Serotype O Strain YNTBa from Yunnan Province of China.

Genome Announc 2017 Jun 1;5(22). Epub 2017 Jun 1.

Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, China

YNTBa is a rabbit-passaged attenuated strain of foot-and-mouth disease virus (FMDV) serotype O. Here, we announce the complete genome sequence of YNTBa, which provides data for further studies on replication, virulence, its determinants, and cell and host tropism of YNTBa.
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http://dx.doi.org/10.1128/genomeA.00393-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5454191PMC
June 2017

Peritumoral cystic meningioma: A report of two cases and review of the literature.

Exp Ther Med 2016 Mar 15;11(3):904-908. Epub 2016 Jan 15.

Department of Neurosurgery, Beijing Sanbo Brain Hospital, Capital Medical University, Beijing 100093, P.R. China.

The present study reported two cases of cystic meningioma. The clinical manifestations, magnetic resonance imaging (MRI) scan and histological aspects of the lesion and the associated cyst were examined. The classification of cystic meningioma was also discussed. The present study focused on the formation, diagnosis and management of the peritumoral cystic meningioma, and aimed to clarify certain contradictions in the literature concerning the formation of the peritumoral cyst meningioma: MRI alone is inadequate to determine the type of cystic meningioma, or to identify neoplastic cells on the cystic wall. In conclusion, surgical removal of the entire cyst is recommended in peritumoral cyst meningioma.
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http://dx.doi.org/10.3892/etm.2016.2999DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4774311PMC
March 2016

Genomic Changes in an Attenuated ZB Strain of Foot-and-Mouth Disease Virus Serotype Asia1 and Comparison with Its Virulent Parental Strain.

Int J Genomics 2014 19;2014:978609. Epub 2014 Oct 19.

Yunnan Tropical and Subtropical Animal Virus Disease Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming 650224, China.

The molecular basis of attenuation of foot-and-mouth disease virus (FMDV) serotype Asia1 ZB strain remains unknown. To understand the genetic changes of attenuation, we compared the entire genomes of three different rabbit-passaged attenuated ZB strains (ZB/CHA/58(att), ZBRF168, and ZBRF188) and their virulent parental strains (ZBCF22 and YNBS/58). The results showed that attenuation may be brought about by 28 common amino acid substitutions in the coding region, with one nucleotide point mutation in the 5'-untranslated region (5'-UTR) and another one in the 3'-UTR. In addition, a total of 21 nucleotides silent mutations had been found after attenuation. These substitutions, alone or in combination, may be responsible for the attenuated phenotype of the ZB strain in cattle. This will contribute to elucidation of attenuating molecular basis of the FMDV ZB strain.
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http://dx.doi.org/10.1155/2014/978609DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4216683PMC
November 2014

Effect of amino acid mutation at position 127 in 3A of a rabbit-attenuated foot-and-mouth disease virus serotype Asia1 on viral replication and infection.

Virol Sin 2014 Oct 14;29(5):291-8. Epub 2014 Oct 14.

Yunnan Tropical and Subtropical Animal Virus Disease Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, 650224, China,

An amino acid mutation (R127→I) in the 3A non-structural protein of an FMDV serotype Asia1 rabbit-attenuated ZB strain was previously found after attenuation of the virus. To explore the effects of this mutation on viral replication and infection, the amino acid residue isoleucine (I) was changed to arginine (R) in the infectious cDNA clone of the rabbit-attenuated ZB strain by sitedirected mutagenesis, and the R127-mutated virus was rescued. BHK monolayer cells and suckling mice were inoculated with the R127-mutated virus to test its growth property and pathogenicity, respectively. The effects of the R127 mutation on viral replication and virulence were analyzed. The data showed that there was a slight difference in plaque morphology between the R127-mutated and wild-type viruses. The growth rate of the mutated virus was lower in BHK-21 cells and its virulence in suckling mice was also attenuated. This study indicates that the R127 mutation in 3A may play an important role in FMDV replication in vitro and in pathogenicity in suckling mice.
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http://dx.doi.org/10.1007/s12250-014-3464-4DOI Listing
October 2014

Fluid-fluid level in cystic vestibular schwannoma: a predictor of peritumoral adhesion.

J Neurosurg 2014 Jan 19;120(1):197-206. Epub 2013 Jul 19.

Departments of Neurosurgery.

Object: The aim of this study was to evaluate the clinical results and surgical outcomes of cystic vestibular schwannomas (VSs) with fluid-fluid levels.

Methods: Forty-five patients with cystic VSs and 86 with solid VSs were enrolled in the study. The patients in the cystic VSs were further divided into those with and without fluid-fluid levels. The clinical and neuroimaging features, intraoperative findings, and surgical outcomes of the 3 groups were retrospectively compared.

Results: Peritumoral adhesion was significantly greater in the fluid-level group (70.8%) than in the nonfluid-level group (28.6%) and the solid group (25.6%; p < 0.0001). Complete removal of the VS occurred significantly less in the fluid-level group (45.8%, 11/24) than in the nonfluid-level group (76.2%, 16/21) and the solid group (75.6%, 65/86; p = 0.015). Postoperative facial nerve function in the fluid-level group was less favorable than in the other 2 groups; good/satisfactory facial nerve function 1 year after surgery was noted in 50.0% cases in the fluid-level group compared with 83.3% cases in the nonfluid-level group (p = 0.038).

Conclusions: Cystic VSs with fluid-fluid levels more frequently adhered to surrounding neurovascular structures and had a less favorable surgical outcome. A possible mechanism of peritumoral adhesion is intratumoral hemorrhage and consequent inflammatory reactions that lead to destruction of the tumor-nerve barrier. These findings may be useful in predicting surgical outcome and planning surgical strategy preoperatively.
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http://dx.doi.org/10.3171/2013.6.JNS121630DOI Listing
January 2014

Localization of transverse-sigmoid sinus junction using preoperative 3D computed tomography: application in retrosigmoid craniotomy.

Neurosurg Rev 2012 Oct 22;35(4):593-8; discussion 598-9. Epub 2012 May 22.

Department of Neurosurgery, Beijing Sanbo Brain Hospital, Capital Medical University, No. 50, Yi-Ke-Song Road, Haidian District, 100093, Beijing, China.

In retrosigmoid craniotomy, neurosurgeons usually depend on surface landmarks and their experience to evaluate the position of transverse-sigmoid sinus junction (TSSJ) and place an appropriate initial burr-hole, which is not accurate each time because of variability in different craniums. The authors introduce a simple procedure based on 3D computed tomography (CT) to localize the TSSJ in retrosigmoid craniotomy. Eighteen patients who underwent retrosigmoid craniotomy were analyzed. On the internal view of skull in 3D CT image, a simulative burr-hole was placed on the margin of transverse-sigmoid sinus groove junction. Then, on the external view of skull in 3D CT image, the center of the simulative burr-hole was marked and a coordinate system was established based on a line connected the digastric point and the asterion. Then the coordinate of the burr-hole's center was measured in this coordinate system. In operation, the burr-hole was placed according to the coordinate measured previously and craniotomy was performed. The margin of TSSJ was exposed in each case. No damage of venous sinus was encountered. Post-operative skull base CT demonstrated a good match between the actual and predicted burr-hole and bone defects only existed along the cut line. This simple method could help in localizing the TSSJ and avoiding the risk of sinus injury and reducing the bone defect. It is sufficiently precise for practical application at surgical planning.
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http://dx.doi.org/10.1007/s10143-012-0395-0DOI Listing
October 2012

Evaluating effects of normobaric oxygen therapy in acute stroke with MRI-based predictive models.

Med Gas Res 2012 Mar 9;2(1). Epub 2012 Mar 9.

Department of Neurology, Massachusetts General Hospital, 55 Fruit Street, Boston MA 02114, USA.

Background: Voxel-based algorithms using acute multiparametric-MRI data have been shown to accurately predict tissue outcome after stroke. We explored the potential of MRI-based predictive algorithms to objectively assess the effects of normobaric oxygen therapy (NBO), an investigational stroke treatment, using data from a pilot study of NBO in acute stroke.

Methods: The pilot study of NBO enrolled 11 patients randomized to NBO administered for 8 hours, and 8 Control patients who received room-air. Serial MRIs were obtained at admission, during gas therapy, post-therapy, and pre-discharge. Diffusion/perfusion MRI data acquired at admission (pre-therapy) was used in generalized linear models to predict the risk of lesion growth at subsequent time points for both treatment scenarios: NBO or Control.

Results: Lesion volume sizes 'during NBO therapy' predicted by Control-models were significantly larger (P = 0.007) than those predicted by NBO models, suggesting that ischemic lesion growth is attenuated during NBO treatment. No significant difference was found between the predicted lesion volumes at later time-points. NBO-treated patients, despite showing larger lesion volumes on Control-models than NBO-models, tended to have reduced lesion growth.

Conclusions: This study shows that NBO has therapeutic potential in acute ischemic stroke, and demonstrates the feasibility of using MRI-based algorithms to evaluate novel treatments in early-phase clinical trials.
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http://dx.doi.org/10.1186/2045-9912-2-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3388462PMC
March 2012

Interexaminer difference in infarct volume measurements on MRI: a source of variance in stroke research.

Stroke 2008 Apr 21;39(4):1171-6. Epub 2008 Feb 21.

Stroke Service, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, 149 13th Street, Room 2301, Charlestown MA 02129, USA.

Background And Purpose: The measurement of ischemic lesion volume on diffusion- (DWI) and perfusion-weighted MRI (PWI) is examiner dependent. We sought to quantify the variance imposed by measurement error in DWI and PWI lesion volume measurements in ischemic stroke.

Methods: Fifty-eight consecutive patients with DWI and PWI within 12 hours of symptom onset and follow-up MRI on >or= day-5 were studied. Two radiologists blinded to each other measured lesion volumes by manual outlining on each image. Interexaminer reliability was evaluated by intraclass correlation coefficients (ICC) and relative paired difference or RPD (ratio of difference between 2 measurements to their mean). The ratio of between-examiner variability to between-subject variability (variance ratio) was calculated for each imaging parameter.

Results: The correlation (ICC) between examiners ranged from 0.93 to 0.99. The median RPD was 10.0% for DWI, 14.1% for mean transit time, 18.9% for cerebral blood flow, 21.0% for cerebral blood volume, 16.8% for DWI/MTT mismatch, and 6.3% for chronic T2-weighted images. There was negative correlation between RPD and lesion volume in all but chronic T2-weighted images. The variance ratio ranged between 0.02 and 0.10.

Conclusions: Despite high correlation between volume measurements of abnormal regions on DWI and PWI by different examiners, substantial differences in individual measurements can still occur. The magnitude of variance from measurement error is primarily determined by the type of imaging and lesion volume. Minimizing this source of variance will better enable imaging to deliver on its promise of smaller sample size.
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http://dx.doi.org/10.1161/STROKEAHA.107.502104DOI Listing
April 2008

AZD2171, a pan-VEGF receptor tyrosine kinase inhibitor, normalizes tumor vasculature and alleviates edema in glioblastoma patients.

Cancer Cell 2007 Jan;11(1):83-95

Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.

Using MRI techniques, we show here that normalization of tumor vessels in recurrent glioblastoma patients by daily administration of AZD2171-an oral tyrosine kinase inhibitor of VEGF receptors-has rapid onset, is prolonged but reversible, and has the significant clinical benefit of alleviating edema. Reversal of normalization began by 28 days, though some features persisted for as long as four months. Basic FGF, SDF1alpha, and viable circulating endothelial cells (CECs) increased when tumors escaped treatment, and circulating progenitor cells (CPCs) increased when tumors progressed after drug interruption. Our study provides insight into different mechanisms of action of this class of drugs in recurrent glioblastoma patients and suggests that the timing of combination therapy may be critical for optimizing activity against this tumor.
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http://dx.doi.org/10.1016/j.ccr.2006.11.021DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2748664PMC
January 2007

Conversion of ischemic brain tissue into infarction increases with age.

Stroke 2005 Dec 3;36(12):2632-6. Epub 2005 Nov 3.

The AA Martinos Center, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.

Background And Purpose: Brain regions normal on diffusion-weighted imaging (DWI) but abnormal on mean transit time (MTT) maps represent tissue at risk of infarction, yet the fate of these regions is quite variable. The imperfect correlation between tissue outcome and initial imaging parameters suggests that each patient's brain may have different susceptibility to ischemic stress. We hypothesize that age is a marker for tissue susceptibility to ischemia and thus plays a role in determining tissue outcome in human stroke.

Methods: Sixty patients with acute ischemic stroke and a region of DWI/MTT mismatch that was >20% of the DWI volume were included. All patients were scanned twice, within 12 hours of symptom onset and on day 5 or later. The percentage mismatch lost (PML) was calculated as percentage of initial DWI/MTT mismatch volume that was infarcted on the follow-up MRI. The statistical analysis explored relationships among the covariates age, Trial of Org 10172 in Acute Stroke Treatment (TOAST) subtypes, time-to-MRI, and initial DWI, MTT volume, mean arterial blood pressure and blood glucose level at admission, and previous history of hypertension and diabetes mellitus.

Results: Univariate comparisons showed that age (P=0.003), hypertension (P=0.009), and diabetes mellitus (P=0.0002) were significantly associated with PML. Regression analyses showed age to be a significant covariate (P=0.02). The regression model predicted a change in PML of approximately 0.65% per year. The adjusted proportion of variance (R2) in PML that could be explained by age alone was 14%.

Conclusions: Age-dependent increase in conversion of ischemic tissue into infarction suggests that age is a biological marker for the variability in tissue outcome in acute human stroke.
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http://dx.doi.org/10.1161/01.STR.0000189991.23918.01DOI Listing
December 2005

Cerebral angiography and MR perfusion images in patients with ischemic cerebral vascular disease.

Chin Med J (Engl) 2002 Nov;115(11):1687-91

Neuroimaging Center, Beijing Neurosurgical Institute, Beijing Tiantan Hospital, Capital University of Medical Sciences, Beijing 100050, China.

Objective: To evaluate the value of perfusion MR imaging and angiographic evidence of collateral circulation in symptomatic patients with ischemic cerebrovascular diseases (ICVD).

Methods: Cerebral angiography and perfusion MR were performed in 16 patients with symptoms of ICVD. Qualitative perfusion maps were calculated for regional cerebral blood volume (rCBV) and mean transit time (MTT).

Results: A total of 27 lesions were seen on the perfusion MR maps (6 infarcts and 21 ischemic lesions) and most of them (26/27) showed a prolonged MTT. MTT is sensitive to the presence of ischemic lesions, but not sufficient in distinguishing infarct from ischemia. All of the infarcts showed a decreased rCBV, while most of the ischemic lesions showed a normal or increased rCBV. When collateral circulation was identified on angiography, most ischemic lesions were not infarcts and had a normal or increased rCBV. The absence of angiographically identifiable cerebral collaterals may not always result in an infarct; 50% had decreased rCBV. Despite the absence of angiographic collaterals, the other half had normal or increased rCBV.

Conclusion: Cerebral angiographic evidence of collateral circulation is important in identifying a favorable outcome in patients with ICVD. However, a lesion with a normal or increased rCBV suggests a sufficient collateral circulation even without angiographic collaterals. Perfusion images may be a potentially useful adjunctive tool in the prediction of the outcome of ICVD, particularly where no apparent collateral macrocirculation is seen on CA.
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November 2002