Clinical lacunar syndromes as predictors of lacunar infarcts. A comparison of acute clinical lacunar syndromes and findings on diffusion-weighted MRI

OBJECTIVES: To evaluate if patients with acute lacunar syndromes have acute lacunar infarcts or other types of cerebral lesions on diffusion-weighted MRI. METHODS: Patients with acute lacunar syndromes underwent echo-planar diffusion MRI of the brain within 3 days after stroke onset. Localization and size of lesions with hyperintense signal were determined, compared with clinical characteristics and with findings on follow-up T2-weighted MRI. RESULTS: Twenty-three patients participated in the study. Thirteen patients had pure motor stroke, 1 pure sensory stroke, 8 sensorimotor stroke, and 1 ataxic hemiparesis. Twenty-two patients had at least one lesion with increased signal on diffusion-weighted MR images. These acute lesions were in the internal capsule/ basal ganglia/thalamus in 13 patients, subcortical white matter in 5 patients, brainstem in 2 patients, cortex (multiple small lesions) in 1 patient, and cortex + basal ganglia in 1 patient. The median volume of the lesions was 0.6 ml on the initial examination and on follow-up, of 17 patients after 1 to 5 months, 0.5 ml. CONCLUSIONS: Almost all patients with acute ischemic lacunar syndromes have acute lesions on echo-planar diffusion-weighted MRI within 3 days after stroke onset. These lesions are mostly small and subcortical, compatible with lacunar infarcts caused by single penetrating artery occlusion, but in a minor proportion of patients (2 of 23 in our study) a cortical involvement is found.     

The classic lacunar syndromes: clinical and neuroimaging correlates

Background:  Although lacunar syndromes (LSs) are aimed to be linked to lacunar infarcts, the relation between both is still not very well defined.
Purpose:  The present retrospective study tries to define more specifically the clinical and the neuroimaging characteristics of the five most classic LSs.
Patients and methods:  Out of a series of 1617 consecutive stroke patients, admitted to the Ghent University Hospital, 293 presented a classic LS. Magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) was performed within 5 days after stroke onset in 227 patients. An acute territorial infarct was demonstrated in 54 patients. The study population finally consisted of 173 patients with a classic LS in whom the responsible lacune was demonstrated or in the absence of another type of infarct.
Results:  The responsible lacune was demonstrated with DWI in 104 patients. Pure motor stroke (MS) correlated significantly with the presence of the responsible lacune in the internal capsule ( P  = 0.000147) and with the stroke severity ( P  = 0.00724). No significant correlation was observed between the location of the lacunes and the other LS's.
Conclusion:  Pure MS has to be considered as the most specific lacunar syndrome.     

Higher severity of frontal periventricular white matter and basal ganglia hyperintensities in first-ever lacunar stroke with multiple silent lacunes

Background and purpose:  We investigated whether patients with a lacunar infarct (LI) syndrome exhibiting unique LI or multiple LI on magnetic resonance imaging (MRI) examinations differed in terms of topography and severity of white matter hyperintensities (WMH) ratings.
Methods:  Forty consecutive patients with a first-ever acute LI, who presented a lacunar syndrome according to Miller–Fisher's classification were recruited and were classified into a group presenting isolated LI on MRI ( n  = 17) or multiple LI ( n  = 23).
Results:  Despite equivalent demographic, clinical and cognitive characteristics, patients with multiple LI had increased ratings of WMH in frontal, occipital and subcortical regions. No significant correlations could be evidenced between the number of LI and WMH ratings.
Conclusions:  Present findings provide support to previous hypothesis considering single and multiple LI MRI presentations of lacunar infarct patients as distinct entities.     

闭锁综合征患者功能磁共振成像检查的诊断价值

目的探讨闭锁综合征(LIS)患者功能磁共振成像(fMRI)检查的诊断价值。方法对1例诊断为不完全性LIS和1例诊断为植物状态的患者进行fMRI检查,分析在唤名和抬手指令时其相关脑区的活动。结果唤名任务中,2例患者在听到各自配偶唤名后,初、高级听觉皮质(BA41/42区,BA21/22区)均激活;抬手任务中,2例患者在听到抬手命令后,初、高级听觉皮质均激活,同时运动相关皮质(初级运动区和辅助运动区)也激活。fMRI检查结果显示,2例患者均意识清楚,其中1例诊断为不完全性LIS无误;另1例诊断为植物状态系误诊,应诊断为完全性LIS。fMRI检查对LIS有鉴别诊断的作用。结论 fMRI可以作为LIS与植物状态鉴别诊断的一种有效辅助检查。     

脑功能磁共振成像研究进展

主要综述fMRI产生的历史、成像原理、成像技术和方法、已经取得的成绩以及将来研究发展的方向等。fMRI产生技术广泛应用的20世纪90年代,主要受快速成像技术的影响,从有创走向无创,从而受到神经、认知和心理科学领域的极大关注。fMRI原理是根据神经元兴奋后局部氧耗与血流增幅不一致,而BOLD效应机制成像,间接显示神经元活动。成像主要采用平面回波成像（EPI）和快速小角度激发（FLASH）技术、二者在时间和空间分辨率上各有优劣。最后几年来,fMRI技术对脑功能的研究已取得了巨大的成绩,估计将在这一领域继续拥有非常重要的地位。将来fMRI可能主要在BOLD效应的生理过程、临床应用以及高场磁体的应用等领域进一步展开。     

MR序列优化组合在创伤性脑损伤的诊断价值

目的分析MR诊断创伤性脑损伤(TBI)的价值,探讨TBI患者MR一站式诊断的可行性。方法对260例TBI病例进行MR序列组合扫描,包括小角度激发快速梯度回波序列(FLASH)、流动衰减反转恢复序列(FLAIR)、自旋回波(SE)T1WI、快速自旋回波(TSE)T2WI,比较MR序列组合和CT对各种类型TBI诊断的差异。结果脑实质内出血61例,MR显示61例,CT显示53例;硬膜下出血55例,MR显示55例,CT显示49例;硬膜外出血45例,MR显示45例,CT显示40例;脑挫(裂)伤35例,MR显示35例,CT显示25例;蛛网膜下腔出血35例,MR显示31例,CT显示33例;弥漫性轴索损伤29例,MR显示29例,CT显示5例。MR序列组合准确显示病变256例,CT为209例,两者差异有极显著统计学意义(P0.01),MR序列组合总体诊断敏感性高于CT。结论 MR序列组合(FLASH\FLAIR\T1WI\T2WI)诊断创伤性脑损伤明显优于CT,可列为TBI常规检查方法,实行TBI一站式诊断。     

Multimodal biological brain age prediction using magnetic resonance imaging and angiography with the identification of predictive regions

Biological brain age predicted using machine learning models based on high‐resolution imaging data has been suggested as a potential biomarker for neurological and cerebrovascular diseases. In this work, we aimed to develop deep learning models to predict the biological brain age using structural magnetic resonance imaging and angiography datasets from a large database of 2074 adults (21–81 years). Since different imaging modalities can provide complementary information, combining them might allow to identify more complex aging patterns, with angiography data, for instance, showing vascular aging effects complementary to the atrophic brain tissue changes seen in T1‐weighted MRI sequences. We used saliency maps to investigate the contribution of cortical, subcortical, and arterial structures to the prediction. Our results show that combining T1‐weighted and angiography MR data led to a significantly improved brain age prediction accuracy, with a mean absolute error of 3.85 years comparing the predicted and chronological age. The most predictive brain regions included the lateral sulcus, the fourth ventricle, and the amygdala, while the brain arteries contributing the most to the prediction included the basilar artery, the middle cerebral artery M2 segments, and the left posterior cerebral artery. Our study proposes a framework for brain age prediction using multimodal imaging, which gives accurate predictions and allows identifying the most predictive regions for this task, which can serve as a surrogate for the brain regions that are most affected by aging.     

Influence of X chromosome and hormones on human brain development: a magnetic resonance imaging and proton magnetic resonance spectroscopy study of Turner syndrome.

BACKGROUND: Women with Turner syndrome (TS; 45,X) lack a normal second X chromosome, and many are prescribed exogenous sex and growth hormones (GH). Hence, they allow us an opportunity to investigate genetic and endocrine influences on brain development. METHODS: We examined brain anatomy and metabolism in 27 adult monosomic TS women and 21 control subjects with volumetric magnetic resonance imaging and magnetic resonance spectroscopy. RESULTS: In TS women, regional gray matter volume was significantly smaller in parieto-occipital cortex and caudate nucleus and larger in cerebellar hemispheres. White matter was reduced in the cerebellar hemispheres, parieto-occipital regions, and splenium of the corpus callosum but was increased in the temporal and orbitofrontal lobes and genui of corpus callosum. Women with TS had a significantly lower parietal lobe concentration of N-acetyl aspartate, and higher hippocampal choline. Also, among women with TS, there were significant differences in regional gray matter volumes and/or neuronal integrity, depending upon parental origin of X chromosome and oxandrolone and GH use. CONCLUSIONS: X chromosome monosomy, imprinting and neuroendocrine milieu modulate human brain development-perhaps in a regionally specific manner.     

A polymorphism of the aldehyde dehydrogenase 2 gene is a risk factor for multiple lacunar infarcts in Japanese men: the Takahata Study

The objective of the present study was to examine the association between a polymorphism of the aldehyde dehydrogenase 2 (ALDH2) gene and lacunar infarcts of the brain. We conducted a population-based, cross-sectional study on residents from two age groups (61- and 72-year olds). A total of 376 subjects participated in the study, which included brain magnetic resonance image and genetic analysis of the ALDH2 gene. Of the 61- and 72-year-old subjects, 46.4% and 64.3%, respectively, had one or more lacunar infarcts. The average number of infarcts also increased from 2.0 to 2.8 in men and from 2.3 to 3.5 in women. No significant association between the ALDH2 genotype and the presence of lacunar infarction (≥1) was found. However, in subjects with lacunar infarction, the genotype of ALDH2 *1/*1 was associated with a larger number of the lesion ['single' versus 'multiple' odds ratio (OR) 3.73, 95%CI: 1.43–9.74] in men. The OR was comparable even after adjusting for alcohol consumption, tobacco habits, age, hypertension, hypercholesterolemia, and diabetes mellitus (DM) (OR 3.88; 95% CI: 1.10–13.66). In women, there was no significant association between the ALDH2 genotypes and lacunar infarcts. The present study revealed that the ALDH2 *1/*1 genotype was significantly associated with the prevalence of multiple lacunar infarcts in Japanese men.     

Susceptibility weighted magnetic resonance imaging of brain: A multifaceted powerful sequence that adds to understanding of acute stroke

Context:

To evaluate the additional information that susceptibility weighted sequences and datasets would provide in acute stroke.

Aims:

The aim of this study were to assess the value addition of susceptibility weighted magnetic resonance imaging (SWI) of brain in patients with acute arterial infarct.

Materials and Methods:

All patients referred for a complete brain magnetic resonance imaging (MRI) between March 2010 and March 2011 at our institution had SWI as part of routine MRI (T1, T2, and diffusion imaging). Retrospective study of 62 consecutive patients with acute arterial infarct was evaluated for the presence of macroscopic hemorrhage, petechial micro-bleeds, dark middle cerebral artery (MCA) sign and prominent vessels in the vicinity of infarct.

Results:

SWI was found to detect hemorrhage not seen on other routine MRI sequences in 22 patients. Out of 62 patients, 17 (10 petechial) had hemorrhage less than 50% and 5 patients had greater than 50% area of hemorrhage. A “dark artery sign” due to thrombus within the artery was seen in 8 out of 62 patients. Prominent cortical and intraparenchymal veins were seen in 14 out of 62 patients.

Conclusions:

SWI has been previously shown to be sensitive in detecting hemorrhage; however is not routinely used in stroke evaluation. Our study shows that SWI, by virtue of identifying unsuspected hemorrhage, central occluded vessel, and venous congestion is additive in value to the routine MR exam and should be part of a routine MR brain in patients suspected of having an acute infarct.     

Correlation between magnetic resonance imaging and clinical parameters in multiple sclerosis

In this study, the course of 60 consecutive multiple sclerosis patients (relapsing-remitting (RR), relapsing-progressive (RP), primary-progressive (PP)) was compared with the number and mean size of the lesions as well as the total load of the lesions as shown on magnetic resonance imaging (MRI). Significant differences were found between RR and RP patients in total load and number of lesions. Between RR and PP patients statistical significant differences were found in total load, number and size of the lesions when correlated with EDSS. Between RP and PP patients statistical differences were found in total load and size of the lesions on MRI. Patients with a relapsing course of the MS (RR or RP) had a higher total load and size of the lesions than PP patients. The total load, number and size of the lesions corrected for EDSS were also lower compared to relapsing patients. Factor analysis showed a correlation between clinical progression rate and progression rate of MRI abnormalities. No correlation between EDSS and total load of MRI lesions could be found. In conclusion, this study confirms the results of previous studies of differences between MRI scans of patients with a different course of MS.     

低血糖脑病的临床及脑部磁共振特征

目的探讨低血糖脑病的临床及脑部磁共振特征。方法回顾分析69例低血糖昏迷患者的临床、脑磁共振（MRI）成像资料。结果低血糖昏迷诱因较为复杂,常见的为进食减少、腹泻、上呼吸道感染、降糖药物应用不当等。临床表现复杂多样,除意识障碍外,还可表现为偏瘫、四肢瘫、凝视麻痹等,多数伴有Babinski征。69例患者中有18例出现脑MRIDWI异常高信号病灶,病灶主要累及海马、基底节、大脑皮质以及皮质下白质,多为对称性损害。3个月后随访,不伴有脑部MRI损害的患者预后良好率明显高于伴有脑部MRI损害的患者（94．12％对22．22％;P=0．0011）。伴有脑部MRI损害者有10例患者预后不良,其中9例（90％）发生于皮质受累患者。结论低血糖脑病临床表现不具有特异性,对于昏迷患者,应当考虑到低血糖的可能。降糖药物应用不当为低血糖脑病的主要诱发因素。脑部MRI要优于脑部CT检查,其中DWI序列对于检测低血糖所致的脑部损害有着非常重要的意义。皮质受累者预后不良。     

The value of magnetic resonance imaging in carpal tunnel syndrome

We examined 62 patients (72 hands) with carpal tunnel syndrome (CTS) by magnetic resonance imaging (MRI) of the carpal tunnel and latency measurements of the median nerve. In 32 of 72 hands a probable causative lesion of the CTS was identified by MRI, for example tenosynovitis, a cyst-like structure, or an aberrant muscle. The MRI findings were confirmed by surgery in 16 of 24 hands, slightly corrected in 5, and not substantiated in 3. In 65 of 72 hands, MRI disclosed pathology of the median nerve, most prominently an enlargement of the nerve at the level of the os pisiforme, a finding not seen during surgery. Oedema of the nerve was found in 14 of 72 hands. The distal latencies were prolonged in 62 of 72 hands. The sensory latencies correlated significantly with the MRI-determined cross-sectional area of the nerve at the level of the distal radius. The lack of other correlations suggests that partly independent features of the nerve lesion are demonstrated in each method or that the sensitivity and specificity of both methods are limited. Further experience with MRI in CTS is desirable. At present, the practical use of MRI in CTS should be restricted to special diagnostic problems such as carpal tunnel syndromes which do not respond adequately to conservative or surgical treatment.     

术中磁共振实时影像导航下穿刺活检术的临床初步应用

目的 探讨术中磁共振(iMRI)影像导航应用于穿刺活检术的临床初步经验、优势与不足.方法 在0.15T PoleStar N-20 iMRI实时影像引导下,对6例颅内占位性质不明患者进行穿刺活检术.结果 6例均获得组织病理学诊断,活检阳性率为100%;1例颅内多发占位患者术后并发左基底节活检区域局限性血肿.结论 iMRI影像导航能及时纠正术中脑移位,即只有当iMRI确定穿刺针已位于病灶内才进行活检,从而有利于提高活检阳性率,减少术后并发症.     

磁共振成像对肾上腺脑白质营养不良的诊断价值

报告４例肾上腺脑白质营养不良（ＡＬＤ）患者的磁共振成像（ＭＲＩ）表现。ＭＲＩ表现为双侧对称的白质异常信号，主要位于枕、顶、颞叶，视放射和胼胝体压部，Ｔ１加权为低信号，Ｔ２加权为高信号，有增强效应。多维成像和高对比强度使ＭＲＩ比ＣＴ有更强的敏感性，能明确病变的部位及其严重程度，故ＭＲＩ是诊断ＡＬＤ的有效手段。     

Distinguishing silent lacunar infarction from enlarged Virchow-Robin spaces: a magnetic resonance imaging and pathological study

We studied clinicopathological correlations between magnetic resonance imaging (MRI) appearances of postmortem brains and pathological findings in 12 patients to identify simple criteria with which to distinguish lacunar infarctions from enlarged Virchow-Robin spaces. In vivo MRI was also available for 6 of the 12 patients. We focused on small, silent, focal lesions including lacunar infarctions and enlarged Virchow-Robin spaces that were confirmed pathologically. From a total of 114 lesions, enlarged Virchow-Robin spaces were most often found in the basal ganglia and had a round or linear shape. Lacunar infarctions also were most frequent in the basal ganglia, but 47% of these were wedge-shaped. In the pathological studies, excluding lesions from the lower basal ganglia region, enlarged Virchow-Robin spaces were usually smaller than 2 × 1 mm. The shapes and sizes of the lesions determined by MRI (in vivo and postmortem) concurred with the pathological findings, except that on MRI the lesions appeared to be about 1 mm larger than found in the pathological study. When lesions from the lower basal ganglia and the brain stem regions are excluded, the sensitivity and specificity for discriminating enlarged Virchow-Robin spaces from lacunar infarctions are optimal when their size is 2 × 1 mm or less in the pathological study (79%/75%, respectively), 2 × 2 mm or less in both of the MRI studies: postmortem (81%/90%), and in vivo (86%/91%). In conclusion, we were able to differentiate most lacunar infarctions from enlarged Virchow-Robin spaces on MRI on the basis of their location, shape and size. We stress that size is the most important factor used to discriminate these lesions on MRI. Received: 14 February 1997 Received in revised form: 12 September 1997 Accepted: 1 October 1997     

Incidental radiological findings on brain magnetic resonance imaging in first-episode psychosis and chronic schizophrenia

OBJECTIVE: To investigate whether patients with first-episode psychosis or chronic schizophrenia have an increased incidence of magnetic resonance imaging (MRI) brain abnormalities compared with control subjects. METHOD: Totally 340 clinical MRI reports [Controls (n=98), first-episode psychoses (n=152), chronic schizophrenia (n=90)] were reported by a neuroradiologist blind to diagnosis and subsequently categorized using referral criteria (immediate, urgent, routine or no referral). RESULTS: Thirty percent of all scans were reported by a neuroradiologist as abnormal, but the majority required no referral. Patients with chronic schizophrenia were more likely to have clinically significant abnormal scans than patients with first episode psychosis or control subjects. In four patients the MRI findings led to the discovery of previously unsuspected pathology. CONCLUSION: Patients with chronic schizophrenia have an increased prevalence of incidental brain abnormalities. A small proportion of patients with chronic schizophrenia and first-episode psychosis benefitted directly from MRI scanning.     

原发性三叉神经痛的磁共振扫描对比研究

目的探讨磁共振对三又神经痛的诊断价值。方法采用3D—FFE序列扫描三叉神经痛60例,患、健侧进行对比,术中进行验证。再与患者配偶60例进行对比。结果磁共振显示研究组患侧明显压迫51例,可疑接触3例,无接触6例,健侧明显压迫14例,可疑接触4例,无接触42例,术中证实患侧都存在明确压迫,其中动脉性压迫57例,静脉性压迫3例。对照组明显压迫15例,可疑接触5例,无接触40例。结论磁共振3D—FFE序列扫描对有三叉神经痛有较高的诊断价值,但对静脉性压迫易漏诊。     

高分辨磁共振成像在脑桥旁正中梗死患者中的诊断价值

目的 探讨高分辨磁共振成像(high resolution magnetic resonance imaging, HRMRI)在脑桥旁正中梗死(paramedian pontine infarction,PPI)患者中的诊断价值。方法 连续收集经磁共振证实的PPI患者32例,全部行磁共振血管成像(magnetic resonance angiography, MRA)和HRMRI检查,利用HRMRI分析动脉粥样硬化斑块在基底动脉(basilar artery, BA)的分布位置,比较MRA与HRMRI识别BA狭窄能力的差异。结果 MRA检查显示BA狭窄者11例(34.4%),HRMRI 显示BA狭窄者27例(84.4%)(P<0.01)。HRMRI显示BA狭窄的27例患者,其粥样硬化斑块位于梗死病灶同侧25例(92.6%)、对侧2例(7.4%)。结论 HRMRI在诊断BA狭窄方面可信度较高; 脑桥旁正中梗死患者BA粥样硬化斑块大多分布在梗死病灶同侧     

Meta-analysis of magnetic resonance imaging brain morphometry studies in bipolar disorder.

BACKGROUND: Several studies assessing volumetric measurements of regional brain structure in bipolar disorder have been published in recent years, but their results have been inconsistent. Our aim was to complete a meta-analysis of regional morphometry in bipolar disorder as assessed using magnetic resonance imaging (MRI). METHODS: We conducted a systematic literature search of MRI studies of bipolar disorder and identified studies which reported volume measurements in a selected number of regions. Twenty-six studies comprising volumetric measurements on up to 404 independent patients with bipolar disorder were included. A meta-analysis was carried out comparing the volumes of regions in bipolar disorder to comparison subjects using a random effects model. RESULTS: Patients with bipolar disorder had enlargement of the right lateral ventricle, but no other regional volumetric deviations which reached significance. Strong heterogeneity existed for several regions, including the third ventricle, left subgenual prefrontal cortex, bilateral amygdala and thalamus. CONCLUSIONS: Regional volume of most structures we studied is preserved in bipolar disorder as a whole, which was significantly associated only with right-sided ventricular enlargement. However the extensive heterogeneity detected indicates the need for further studies to establish if consistent regional brain volume deviation exists in bipolar disorder or in specific clinical subsets of the illness.