应用低场磁共振成像诊断高血压脑出血的探讨

讨论了２６３例高血压脑出血超急性期及急性期血肿在低磁场磁共振成像中的信号特征，在Ｔ１加权像表现为高信号，Ｔ２加权像为混杂信号，与中、高磁场ＭＲＩ图像有所不同。低磁场ＭＲＩ对显示超急性期及急性期脑出血有较高的诊断敏感性和准确性。     

The value of MRI in angiogram-negative intracranial haemorrhage

In one year, cerebral angiograms were performed for intracranial haemorrhage (ICH) on 334 patients. No cause for haemorrhage could be identified in 41 (12%), 30 of whom had predominantly subarachnoid (SAH) and 11 predominantly parenchymal haemorrhage (PH). These patients were prospectively examined by cranial MRI 1–6 weeks after the ictus. The MRI studies were positive in 7 patients (17%). In the 30 patients examined after SAH, 2 studies were positive, showing an aneurysm in one case and a brain stem lesion of uncertain actiology in the other. In those examined after PH, cavernous angiomas were shown in 2, a tumour in 1 and a vascular malformation in another; useful diagnostic information was thus obtained in 36% of this group.     

Multislice continuous arterial spin-labeled perfusion MRI in patients with chronic occlusive cerebrovascular disease: a correlative study with CO2 PET validation

PURPOSE: To compare the use of multislice continuous arterial spin labeling (CASL) and CO(2) positron emission tomography (PET) to assess CBF in patients with chronic occlusive cerebrovascular disease for the validation of quantitative CASL perfusion in an altered hemodynamic state. MATERIALS AND METHODS: Eleven patients with occlusive carotid artery disease were studied with CASL and conventional MRI. Cerebral blood flow (CBF) was also measured with O(15)-labeled CO(2) gas using a whole-body PET scanner. The average values within region of interests (ROIs) drawn on coregistered CASL and PET images were used for the linear regression analysis and to assess the effect of transit time on the quantification using CASL. RESULT: In all patients there was a significant correlation between the CBF values from CASL and PET (r = 0.71 +/- 0.07, P < 0.001). The slope of regression lines varied widely among patients (0.54-1.77). Longer transit times were estimated in four of 11 patients in the hypoperfusion region. CONCLUSION: Quantification of CBF using CASL is feasible and reasonable, even when employed in a routine clinical setting. However, the long transit time may lead to underestimation of the affected side in occlusive cerebrovascular disease.     

Visualisation of intracerebral haemorrhage with flat-detector CT compared to multislice CT: results in 44 cases

The aim of the study was to test the reliability of intracerebral haemorrhage (ICH) detection with C-arm-mounted flat-detector computed tomography (FD-CT) in the angio suite as compared to multislice CT (MSCT). In this study 44 patients with 45 ICH were included. All patients were investigated with MSCT and FD-CT during angiographic evaluation. As a control group we included 16 patients without ICH. In each haematoma we assessed volumetric data of the ICH and counted the numbers of ICH-positive slices. Using interobserver ratings, we additionally investigated the potential of FD-CT to serve as a diagnostic tool to detect ICH. In FD-CT three haematomas were not detected because of motion and beam-hardening artefacts in the region close to the skull base. The r value for the degree of interobserver agreement for the number of slices was 0.95 for MSCT and 0.94 for FD-CT. Measurements of the area and the calculated volume of the ICH showed high inter- and intraobserver agreement. Our results indicate that FD-CT is a helpful tool in the daily emergency management of ICH patients as detection of ICH was found to be nearly as reliable as in MSCT. Limitations of this technology are motion and beam-hardening artefacts that may mask small haematomas located in the posterior fossa or the skull base.     

Moyamoya disease and intracerebral hematoma

Summary This report concerns a hypertensive woman who suffered a stroke at the age of 51 and recovered from left hemiparesis after 3 to 4 months. During the subsequent 24 years she had four seizures which involved the left arm and face and became generalized, ending with left hemiparesis, from which she recovered after 4 to 5 days. Carotid angiography was performed in 1967, 1973 and 1974 and the characteristic picture of moyamoya disease was demonstrated. She died at the age of 77 with extensive vascular disease. The literature concerning 215 cases of moyamoya disease, in which there were 14 intracerebral hematomas, is reviewed and discussed.     

MRI T1 W-SPACE对缺血性脑血管病的诊断价值

目的：探讨反转角快速自旋回波的三维脑动脉血管壁成像(T1 W-SPACE)技术对缺血性脑血管疾病诊断的可行性,并与磁共振定位扫描血管成像(TOF-MRA)比较,以全面认识和评估该方法。方法收集患有脑卒中但病情稳定的50例患者,包括既往有短暂性脑缺血(TIA)或有脑卒中病史,先行 TOF-MRA 及常规 MRI 序列检查,然后进行 T1 W-SPACE 检查。结果50例患者中,MRI 常规序列阳性43例,TOF-MRA 发现血管狭窄病变76支,T1 W-SPACE 发现血管狭窄病变73支,两者差异无统计学意义(χ2=0.625,P >0.05);常规 TOF-MRA 无法观察血管壁,T1 W-SPACE 发现动脉血管壁增厚、斑块的病变血管数48支。结论与TOF-MRA 比较,T1 WI-SPACE 不仅可以观察血管腔是否存在狭窄,还可以观察血管壁及斑块,并可以从病理角度对斑块进行分型,对脑中风的早期预防和治疗有重要临床意义。     

缺血性脑血管病患者多层螺旋CT血管造影情况分析

目的根据螺旋CT血管造影（CTA）情况,探讨缺血性脑血管病患者颅内外血管粥样硬化斑块的性质、成分和动脉管腔狭窄程度与缺血性脑血管病的关系。方法选择缺血性脑血管病患者45例,经头颈部螺旋CT血管造影（CTA）,分析脑动脉管腔狭窄程度及动脉粥样斑块的性质、成分。结果45例患者中,CTA检出各种斑块（钙化斑、软斑、混合斑）33例（73．3％）,22例（48．8％）有动脉狭窄,血管闭塞5例。颅外动脉狭窄最常见的部位是颈内动脉起始部,颅内动脉狭窄最常见的部位是大脑中动脉M1段。结论缺血性脑血管病患者的颅内外动脉斑块发生率均较高,动脉粥样硬化致血管狭窄前循环发生率高于后循环,Ⅲ、Ⅳ级狭窄动脉相应供血区域大多出现缺血病灶,头颈动脉多层CTA可以准确评价颅内外动脉的病变情况,对脑卒中的二级预防具有重要指导意义。     

缺血性脑血管病全脑血管造影效果分析

目的 观察缺血性脑血管病患者脑血管造影显示的血管狭窄或闭塞的比率及分布;探讨缺血性脑血管病与侧支循环代偿的关系,为动脉狭窄的诊断和干预提供依据.方法 回顾性分析138例经CT或MRI筛选的缺血性脑血管病患者的DSA资料.分析血管狭窄部位、受累血管数目、血管狭窄形态及侧支循环代偿.结果 血管造影检测出颅内外血管病变患者102例（73.91%）,共累计血管病变有268处.前循环受累158处,后循环受累93处,锁骨下动脉（SUB）受累17处.102例狭窄或闭塞患者中,脑梗死组与TIA组动脉病变分布差异无统计学意义（P〉0.05）.血管狭窄或闭塞与前循环症状相关65例,占65.66%;与后循环症状相关28例,占71.79%.47例严重狭窄或闭塞患者中有39例出现明显代偿,其中仅前交通开放9例,仅后交通开放13例,前后交通同时开放17例,合并其他代偿途径4例.结论 动脉血管病变在缺血性脑血管病中起重要作用.血管狭窄或闭塞与临床症状有密切联系.侧支循环代偿在动脉狭窄或闭塞患者中起着重要作用,其对决定是否进行干预治疗有重要意义.     

Dynamic contrast-enhanced T2*-weighted MRI in patients with cerebrovascular disease

Our purpose was to investigate the potential of dynamic susceptibility contrast-enhanced MRI in assessing regional haemodynamics in patients with cerebrovascular disease. T2^*-weighted FLASH sequences were performed on a control group of 10 healthy subjects, 13 patients with unilateral stenosis or occlusion of the internal carotid artery and 6 patients with acute onset of neurological symptoms, the observed signal intensities being converted into concentration-time curves. A gamma-variate function was fitted to the measured concentration-time curves to eliminate effects of tracer recirculation. In each patient the two cerebral hemispheres were compared and the difference between the mean transit times and the percental change of the regional cerebral blood volume, calculated for each side. Patients with haemodynamically significant unilateral carotid obstruction can be divided into two subgroups: those with good and those with poor collateral supply. Patients with good collateral supply had a slight but not statistically significant increase in mean transit time and cerebral blood volume on the diseased side, whereas those with poor collaterals had a significant increase compared with the control group. In patients with acute onset of neurological symptoms perfusion maps clearly demonstrated the disturbed perfusion at a time when T2-weighted images were still normal. Perfusion imaging is a reliable and noninvasive method of assessing changes in cerebral perfusion in patients with unilateral carotid stenosis. This MR technique permits monitoring of haemodynamic changes during therapy and thus may become an alternative to SPECT and PET scanning. In patients with acute occlusion of a cerebral artery, perfusion imaging reveals the entire perfusion deficit before conventional MRI and thus allows early intervention. Received: 10 April 1996 Accepted: 14 June 1996     

颈部血管彩超对缺血性脑血管病患者颈部动脉血管病变的诊断价值

目的探讨颈部血管彩超对缺血性脑血管病患者颈部动脉血管病变的诊断价值。方法 51例经头部CT或MRI及临床确诊的缺血性脑血管病患者,均进行了多层螺旋CT血管成像（CTA）和颈部血管超声（CVUS）检查,以CTA为对照,评价颈部血管彩超的诊断价值。结果 CTA和CVUS发现颈动脉狭窄及闭塞分别为20例、17例,椎动脉狭窄或发育异常分别为29例、15例。结论对于颈动脉狭窄的评价,颈部血管彩超和CTA具有很好的一致性,但颈部血管彩超对椎动脉病变的评价不足,联合使用CVUS和CTA可以更全面地评价缺血性脑血管病患者的颈部动脉病变。     

多巴胺阶段性输注在缺血性脑血管病患者介入治疗中的应用

目的 观察多巴胺阶段性输注对缺血性脑血管病介入治疗患者的影响.方法 选择拟在全身麻醉下行血管内介入治疗的缺血性脑血管病患者100例,性别不限,年龄35～80岁,体重40～100 kg,体质指数(BMI) 18～25 kg/m2,美国麻醉医师协会(ASA)分级Ⅰ～Ⅲ级.随机分为两组,A组(n=50)患者于麻醉诱导开始时静脉持续输注多巴胺8μg· kg-1·min-1,B组(n=50)患者同一时刻泵注等量生理盐水作空白对照;两组患者分别于支架植入成功时停止泵注多巴胺或生理盐水,控制血压于基础水平低值,以防止脑血管再通后缺血-再灌注损伤.两组患者均接受相同药物作麻醉诱导、麻醉维持,接受相同补液速度,尽量减少引起围术期循环波动的混杂因素.观察并记录患者入手术室时、麻醉过程及苏醒期心率、平均动脉压变化及苏醒时间、血管活性药物使用情况.结果 A组患者血压较B组平稳,额外使用多巴胺次数较少;A组患者麻醉苏醒期呼吸恢复时间、呼之睁眼时间较B组时间短,差异均有统计学意义(P＜0.05).结论 缺血性脑血管病患者支架植入前接受多巴胺输注,可更好地维持循环指标于目标水平,保证良好脑灌注,并可缩短患者苏醒所需时间.     

CT and MRI findings with pathological correlation of an intracerebral malignant fibrous histiocytoma (MFH): a case report

The CT and MRI findings in a case of an intracranial malignant fibrous histiocytoma are reported. Pathological correlation was demonstrated and tumour vascularization was best seen at angiography. Despite its low incidence in brain. MFH is of special interest because of its ubiquitous location and poor prognosis.Correspondence to: C. Berchtenbreiter     

MRI in patients with inflammatory bowel disease

Inflammatory bowel disease (IBD) affects ≈1.4 million people in North America and, because of its typical early age of onset and episodic disease course, IBD patients often undergo numerous imaging studies over the course of their lifetimes. Computed tomography (CT) has become the standard imaging modality for assessment of IBD patients because of its widespread availability, rapid image acquisition, and ability to evaluate intraluminal and extraluminal disease. However, repetitive CT imaging has been associated with a significant ionizing radiation risk to patients, making MRI an appealing alternative IBD imaging modality. Pelvic MRI is currently the imaging gold standard for detecting perianal disease, while recent studies indicate that MRI bowel-directed techniques (enteroclysis, enterography, colonography) can accurately evaluate bowel inflammation in IBD. With recent technical innovations leading to faster and higher resolution body MRI, the role of MRI in IBD evaluation is likely to continue to expand. Future applications include surveillance imaging, detection of mural fibrosis, and early assessment of therapy response.     

Wilson's disease: MRI with clinical correlation

We tried to establish possible correlations between clinical data and MRI in a group of patients with Wilson's disease. Eleven patients (6 male, 5 female), aged between 11 and 50 years old, with a duration of illness from 5 months to 32 years, were submitted to MRI on a 1.5 T System. Three patients were asymptomatic, two had mild neurological disturbances, two were moderately affected and the remaining four had a severe form of the disease. All were receiving D-penicillamine at the time of the study. In the most symptomatic patients there were abnormalities in five or more sites on MRI. The putamen was affected in all symptomatic patients, including five with dystonia. A striking feature was the peripheral location of high signal putaminal lesions on T2-weighted images. In five cases, lesions in the corpus striatum or substancia nigra explained the patient's Parkinsonian features. MRI is an efficient method for studying involvement of the central nervous system in Wilson's disease, and allows some interesting anatomoclinical correlations.     

MRI of intracerebral haematoma at low field (0.15T) using T2 dependent partial saturation sequences

Summary Results of MRI at 0.15T in twelve successive patients with intracerebral haematoma are reviewed. Using T₂ weighted spin echo (SE) and partial saturation (PS without a refocussing 180° pulse) sequences, low intensity areas were seen in eleven of the twelve cases. These included central regions (three cases), a peripheral rim (seven cases) and more diffuse patterns involving the brainstem and cerebral hemispheres (two cases). One case initially displayed a peripheral rim and later a central low intensity region. Central low intensity regions were seen in acute, subacute, and chronic cases. Follow up in five cases displayed an increase in signal within the haematoma in three cases and a decrease in signal intensity in two cases. Low signal intensity areas can be seen within and around intracerebral haematomas imaged with T₂ weighted sequences at low field strength.     

MRI in acute subarachnoid haemorrhage; findings with a standardised stroke protocol

There is doubt as to whether acute haemorrhage is visible on MRI. We carried out MRI within 6 h of symptom onset on five patients with minor (low Hunt and Hess grades 1 or 2) subarachnoid haemorrhage (SAH) diagnosed by CT to search for any specific pattern. We used our standard stroke MRI protocol, including multiecho proton density (PD)- and T2-weighted images, echoplanar (EPI) diffusion- (DWI) and perfusion- (PWI) weighted imaging, and MRA. In all cases SAH was clearly visible on PD-weighted images with a short TE. In four patients it caused a low-signal rim on the T2*-weighted source images of PWI, and DWI revealed high signal in SAH. In the fifth patient SAH was perimesencephalic; susceptibility effects from the skull base made it impossible to detect SAH on EPI DWI and T2*-weighted images. Perfusion maps were normal in all cases. MRA and conventional angiography revealed an aneurysm in only one patient. Stroke MRI within 6 h of SAH thus shows a characteristic pattern.     

Hypoparathyroidism and intracerebral calcification in patients with beta-thalassemia major

Background

Hypoparathyroidism is one of the most important endocrine complications of thalassemia major. This study was conducted to evaluate the prevalence of intracerebral calcifications in patients with thalassemia with and without hypoparathyroidism.

Methods

47 beta-thalassemia patients with hypoparathyroidism underwent a brain CT scan to investigate the presence and extent of intracerebral calcification. 30 age- and sex-matched beta-thalassemic patients with normal parathyroid function who had undergone brain CT for headache, or some other minor neurologic problems were also enrolled in the study serving as controls. The amount of intracerebral calcification, hematologic parameters, and some clinical findings were compared between both groups.

Results

Intracerebral calcification was present in 54.2% of beta-thalassemia patients with hypoparathyroidism. The most frequent sites of calcification were basal ganglia, and frontoparietal areas of the brain. Thalami, internal capsule, cerebellum and posterior fossa were other less frequently calcified regions of the brain. In contrast, there was no evidence of intracerebral calcifications in the 30 thalassemic patients with normal parathyroid function.There was not a statistically significant difference between serum ferritin concentrations in thalassemia patient with hypoparathyroidism and those with normal parathyroid function (2781 vs. 2178, P > 0.05).

Conclusion

Intracranial calcification is a common finding in thalassemia patients with hypoparathyroidism, it can be extensive and involves most regions of the brain.