彩色多普勒和磁共振对健康人颅内动脉影像学的比较研究

目的通过彩色多普勒和磁共振血管成像对健康人颅内动脉的检测,初步确定其操作规范及衡量标准。方法正常人200例,按照检查方法分为彩色多普勒血流显像(ColourDopplerFlowImaging,CDFI)组及磁共振血管成像(MagneticReso-nanceAngiography,MRA)组。CDFI组观察大脑中动脉(MiddleCerebralArtery,MCA)、椎动脉(VertebralArtery,VA)各段的血流动力学改变和相应点的血流束内径。MRA组检测相应血管对应部位的血管内径。结果同一条血管不同位置的血流速率有差异(P<0.05);同名血管相应位置的血流速率左侧略高于右侧,女组高于男组,但无统计学意义(P>0.05)。按年龄分组,相邻组间无显著性差异,相隔组间有显著性差异。CDFI所测血流束内径较MRA所测血管内径值偏高,且P<0.05,差异有显著性。结论a)应用CDFI能显示MCA,VA走行,可检测血管的血流动力学的改变。b)要提高临床脑血管疾病诊断的准确性,必须有规范的临床操作和可靠的检测指标。c)对血管内径的测量MRA更佳。     

Conventional MRA and contrast- enhanced MRA of extracranial vessel segments

Summary The introduction of fast gradient systems allows a reliable visualization of the extracranial carotid vessels by the magnetic resonance angiography (MRA) which meanwhile is implemented into clinical routine. By the mainly applied time-of-flight (TOF) technique, vessels can be imaged without contrast agent (CA). Due to the application of ultra-fast gradient-echo-sequences, the first-pass evaluation of an intravenous bolus-injection of Gadolinium in the carotids from the aortic arch up to the skull base can be performed in less than 30 s. In this study, advantages and disadvantages of both techniques are discussed. For a qualitatively optimal contrast enhanced MRA (CE-MRA) timing parameters like injection delay, flow rate and the adjustment of sequence parameters have to be considered in relation to the fast venous return from the sinus to the jugular veins. First, the optimal time point of the data acquisition have been determined at a model and with a computer simulation in reference to the presence of CA in the arteries. As a result, 90 % of the contrast contribution is defined by 16 % of the symmetrically acquired central k-space lines. A measuring protocol for clinical use was obtained by a gradual variation of spacial resolution, measuring time and CA-injection parameters and was proved in normal volunteers and patients. An exact determination of the bolus-arrival-time by means of a test-bolus injection was acquired. The best qualitative results were achieved by a double-dose injection at 2 ml/s injection rate. The temporal reserves of ultra-fast sequences should be invested in the improvement of the spatial resolution. To date, further investigations related to the problem of optimal CA-application may improve the potentials of CE-MRA procedures.      

Long‐standing ulcerative colitis complicated by right subclavian artery occlusion and upper limbs arteriolitis with digital ischemia

A 48‐year‐old male patient with long‐standing ulcerative colitis since February 2001 which was diagnosed by endoscopy, developed acute digital ischemia affecting both hands with fixed colour changes in the left index finger which was followed shortly by digital ulceration. Magnetic resonance angiography (MRA) of both upper limbs showed evidence of vasculitis affecting digital arterioles on both sided and right subclavian occlusion. The patient received pulse methylprednisolone followed by cyclophosphamide pulse therapy, the latter continuing on a monthly basis for 6 months with appreciable improvement and remission of the vasculitic process; follow‐up MRA showed reperfusion of the previously occluded subcalvian artery. To the authors’ knowledge vasculitis complicating the course of ulcerative colitis is a rare association and is only sporadically reported in the literature. This rare entity should be diagnosed early and aggressively treated; MRA is a very promising diagnostic tool that is suitable for both diagnosis and follow‐up of patients with this rare entity.     

脑血管畸形的CT、MRI及MRA诊断(附16例报告)

目的　探讨CT、MRI及MRA在脑血管畸形中的诊断价值。方法　搜集经血管造影和手术病理证实的脑血管畸形16例,包括动静脉畸形(AVM)12例,海绵状血管瘤4例。所有病例均行CT、MRI平扫及MRA检查,MRA采用3D-TOF法。结果　AVM的CT平扫主要表现为低、等或高混杂密度,部分伴钙化,合并急性出血者呈高密度。MRI扫描T     

Glomus vagale presenting as a supraclavicular mass: Magnetic resonance imaging findings

Glomus vagale are rare vascular tumours of the paraganglion cells of the vagus nerve, and they usually occur in the carotid space. Tumours can be familial, multicentric, malignant but rarely hormonally active. A rare case is reported of glomus vagale presenting as a supraclavicular mass.     

MRI评价肺动静脉瘘

目的　评价MRI、MRA等对肺部血管畸形的临床应用价值。方法　分析了 6例手术或血管造影证实的AVF病例的多种表现 ,其中男 5例 ,女 1例 ,采用 1.0T超导MRI仪 ,体线圈技术。分别行SE、2D TOF、3D TOF及cine MRI多种序列成像 ,共行 3 5次MRI和MRA等检查。结果　 6例AVF中共发现 9个病灶。 2例共 3个病灶在SE序列中可见大小不等流空信号 ,其余为等信号之软组织块影、边缘不规则 ;在梯度回波序列 (2D、3D TOF及cine MRI)中病灶均呈高信号或极高信号影 ,在2D TOF中可见到 5例病灶的供血动脉及 3例引流静脉 ;在 3D TOF中可见到 4例病灶的供血动脉及 2例引流静脉 ;在cine MRI序列中可见到 3例病灶供血动脉及 2例引流静脉 ,且cine MRI可见到 5例病灶内信号强弱变化同心动周期一致。结论　目前 ,MRI多种序列的结合应用 ,可以较准确地诊断AVF ,作为一种无创性诊断方法有一定临床应用价值。     

后循环缺血的MRA表现及临床特点

目的:探讨后循环缺血的MRA表现及临床特点。方法:对39例后循环缺血的患者进行头颅CT/MRI、MRA、颈动脉多普勒超声、心电图、心脏超声检查,分析其血管病变类型及部位,并观察其发病的危险因素和临床表现。结果:本组病例中有38例患者MRA检查均有不同程度的椎基底动脉病变,病变部位最常见在V2段,其次在V4段和椎动脉起始段(V0),同时伴有颈内动脉病变者19例(48.7%);最常见的危险因素依次为高血压、糖尿病和吸烟;最常见的临床表现分别为眩晕、复视、共济失调和肢体乏力。结论:MRA是检测后循环缺血简便有效的方法,能提供可靠的临床信息。     

Posterior cerebral artery dissection on a serial magnetic resonance angiography

Posterior cerebral artery (PCA) dissection in children seldom is reported in the literature. This is the second report of acute PCA dissection with infarct occurring in a young child. A serial magnetic resonance angiography demonstrated a delayed and transient narrowing of the arterial caliber, which was consistent with a focal PCA dissection with delayed vascular recanalization. PCA dissection should be included in the causes of infarct in children and a thorough and serial neurovascular imaging should be considered if no cause of stroke is found.