颅内动静脉瘘的CT和MRI诊断价值

目的:探讨CT和MRI对颅内动静脉瘘的诊断价值。方法:回顾性分析18例颅内动静脉瘘的CT和MRI表现。18例均经DSA检查明确诊断。其中12例行CT检查;16例行MRI检查,同期6例行MRA检查。结果:颅内动静脉瘘的CT和MRI的特征性表现为脑沟、脑裂、基底池内血管影增粗、增多,呈散在分布,受累及的静脉窦增粗,且病变区没有畸形血管团。海绵窦硬脑膜动静脉瘘在T2WI上表现为局部流空信号增宽,MRA原始图像显示局部有较丰富的异常纤细血流信号。结论:认识颅内动静脉瘘的CT和MRI表现,有助于早期诊断及治疗。MRI对显示软脑膜血管扩张优于CT。选择性脑血管造影是确诊本病的可靠手段。     

椎基底动脉延长纡曲症的MRI评价

目的探讨椎基底动脉延长纡曲症（VBD）的MRI表现及其临床意义。资料与方法回顾分析21例VBD患者的影像资料。21例均接受MR头颅平扫，13例行头颅磁共振血管造影（MRA），4例有强化，12例接受螺旋CT平扫。利用MRI对基底动脉的各项指标进行评价、分析。结果2l例MRI表现为基底动脉明显扩张，直径为5-10mm，其中13例向右扭曲延长；8例向左扭曲延长。14例有第Ⅶ、Ⅷ、Ⅺ、Ⅴ对颅神经受累症状。8例在MRI平扫中见后循环梗死灶。结论MRI及MRA联合应用可以清楚显示基底动脉的解剖及其与后颅凹结构的关系，显示附壁血栓和夹层动脉瘤。可作为VBD诊断的首选影像学方法。     

常规MRI联合MRA对椎基底动脉迂曲扩张症的诊断价值

目的探讨椎基底动脉迂曲扩张症（VBD）的MRI、MRA表现及其临床应用价值。方法回顾分析19例VBD的影像资料,分析MRA显示的异常血管形态及MRI显示的脑组织信号、颅神经走行改变,总结其临床特点和影像特征。结果19例患者MRA表现为椎基底动脉迂曲、扩张,直径为5～20mm,长度约为31～35mm;其中10例向右侧偏曲,9例向左侧偏曲;5例并大脑后动脉狭窄;9例血管与颅神经关系密切,7例MRI平扫见后循环梗死灶。结论VBD的临床表现多样,常规MRI联合MRA可清楚显示血管解剖及其与后颅窝脑组织关系,有助于VBD的确诊及全面综合评估。     

长巨脑动脉的MR综合成像

目的探讨长巨脑动脉MR多种成像方法的综合诊断价值。资料与方法对8例长巨脑动脉患者的MRI表现，磁共振血管成像（MRA）及多平面重组（MPR）、曲面重组（CPR）显示的异常血管分布、形态、信号强度进行分析。结果MRI能够明确显示椎一基底动脉的异常血管结构，以及相邻脑组织或颅神经的受压改变；MRA可直观显示迂曲延长、增粗的异常血管全貌；MPR则可以综合上述两种成像方法，同时显示异常血管的全貌以及相邻脑组织或颅神经的受压改变；CPR可将异常血管在同一平面展示，对显示迂曲血管最敏感。8例均发生在椎一基底动脉系统，其中2例累及基底动脉全段和左侧椎动脉，2例并发脑干梗死。结论MRI和MRA、MPR及CPR相结合，有助于该病的全面综合评价。     

Klippel-Trenaunay综合征的MRI诊断

目的分析Klippel—Trenaunay综合征（KTS）的MRI影像表现，评价其在KTS诊断中的作用。方法对经临床和影像检查符合KTS诊断标准的31例KTS患者患肢进行MR常规扫描、MR血管成像（MRA）、静脉血管成像（MRV）和X线顺行静脉造影（XRV）检查，并观察肢体及静脉病变情况。结果12例MRI发现肢体软组织内血管瘤。软组织肥大27例。浅静脉曲张21例。静脉畸形27例。20例同时行MRV与下肢XRV的患者显示浅静脉曲张和特征性坐骨神经均分别为17和11例。下肢XRV检查显示静脉属支增多10例；MRV显示静脉属支增多15例和静脉行径异常4例。MRV显示深静脉异常8例，下肢XRV显示深静脉异常7例。结论MRI是诊断KTS有效和可靠的影像检查方法。     

MR血管成像诊断脊髓动静脉畸形的价值

目的 探讨磁共振血管成像(包括快速3D增强MRA技术和常规MRA)在脊髓动静脉畸形的诊断价值.方法 回顾分析10例脊髓动静脉畸形MRA资料,均由选择性脊髓血管造影确诊,全部病例均使用3D增强MRA技术(CE-MRA),头颈部另外还使用常规MRA(3D-TOF MRA).结果 髓内动静脉畸形3例,AVM血管巢的MRA表现为血管粗细不一,扭曲成团,并显示1条或多条供血动脉及增粗的引流静脉.髓外硬膜内动静脉畸形5例,其中3例为AVM,MRA显示有血管巢、供血动脉及引流静脉;2例为AVF,MRA可以显示供血动脉及引流静脉,并可推断瘘口的位置.硬脊膜动静脉瘘2例,MRA只表现为髓周血管扩张.结论 MRA不仅可以对脊髓动静脉畸形作定性诊断,而且还可以显示病灶的内部结构,已成为无创性诊断脊髓血管畸形的理想方法.     

3.0TMRI常规序列及MRA对可逆性脑血管收缩综合征的诊断价值

目的：探讨 MRI 各序列与 MRA 对可逆性脑血管收缩综合征(RCVS)的诊断价值。方法回顾性分析明确诊断的5例RCVS 患者的临床资料和 MRI 及 MRA 显示的异常血管分布、形态、脑实质病变信号特点。结果5例 MRA 结果均显示颅内外大动脉呈非动脉硬化性、非炎症性、多发节段性狭窄与扩张,典型者呈“串珠样”改变,有4例并发颅脑病变,其中1例合并后部可逆性脑病综合征(PRES),局部皮层蛛网膜下腔出血1例,分水岭区脑梗死3例。5例治疗后3个月复查 MRI 及 MRA 完全恢复正常。结论MRI 及 MRA 能清楚显示脑血管形态,观察脑实质的继发性病变,对临床治疗和预后的评估具有重要的指导意义。     

子宫妊娠残留物的MRI影像表现及临床分析

目的 探讨子宫妊娠残留物（RPOC）的MRI影像特征及其临床价值。方法 回顾性分析经本院临床证实的36例RPOC的MRI影像表现及临床资料。结果 MRI平扫T₂WI、T₁WI均以混杂信号为主；动态对比增强磁共振成像（DCE-MRI）示30例RPOC呈持续型强化，18例强化向RPOC中心延伸，13例呈迂曲条状血管或类血管样强化，12例呈实性肿块样强化，5例呈斑点、条状强化，20例邻近子宫血管增粗、增多，并1例动静脉瘘，6例无强化；RPOC位于或部分位于宫角12例，剖宫产瘢痕处17例，其他部位7例；34例RPOC局部子宫壁变薄，10例RPOC粘连，16例RPOC植入，7例RPOC穿透，3例无植入；RPOC扩散不受限或稍受限；临床诊断7例RPOC穿透并1例植入膀胱后壁、1例植入子宫左侧阔韧带，17例RPOC植入，8例RPOC粘连，4例无植入。结论 RPOC的MRI表现具有一定特点，DCE-MRI有助于其定位及范围评估，可为临床治疗提供有力的评估依据。     

磁共振血管成像在脑血管疾病中的诊断价值

目的：探讨磁共振血管成像（MRA）技术在脑血管疾病中的诊断价值。方法：对23例脑血管疾病患者进行影像分析。结果：经MRA证实脑梗塞10例；动静脉畸形（AVM）2例，动脉瘤5例；脑肿瘤3例；椎动脉供血不足2例；烟雾病1例。结论：在不同血管疾病中适当地选择应用MRA不同成像技术，可以提高对各种脑血管疾病评价的准确性和诊断价值。     

烟雾病的MRI和MRA征象

目的:分析27例烟雾病(moyamoya disease,MMD)的MRI和MRA征象,以进一步提高对烟雾病的诊断水平。方法:回顾性分析27例经颅脑MRI及MRA检查并符合日本烟雾病研究委员会1997年制定的烟雾病诊断标准的MMD患者的影像资料,总结其MRI和MRA的特征性表现。结果:MRI可清晰显示MMD患者的脑梗死、脑出血、脑软化、脑萎缩等脑实质损害表现,亦可见脑基底部异常扩张迂曲的低信号血管网;5例于T1WI和FLAIR见柔脑膜征;3D-TOF MRA直接显示了颈内动脉末端和/(或)大脑前中动脉近端闭塞或狭窄、烟雾状血管团及脑侧支循环;CE-MRA显示侧支血管更清晰;MRI显示的脑损害表现与MRA显示的血管狭窄或闭塞情况不完全一致,与脑侧支循环血管形成关系密切。结论:MMD的MRA征象具有特征性,MRI表现的烟雾状流空血管影及柔脑膜征亦具特征性,但显示不如MRA直观;MRI脑损害征象与MRA的侧支循环表现具有密切关系;MRI和MRA可对MMD明确诊断。     

Phase-contrast MR angiography of intracranial dural arteriovenous fistulae

MRI and phase-contrast MR angiography (PC MRA) were obtained in 13 patients with angiographically confirmed intracranial dural arteriovenous fistulae (DAVF). Three- and two-dimensional PC MRA was obtained with low (6–20 cm/s) and high (> 40 cm/s) velocity encoding along the three main body axes. MRI showed focal or diffuse signal abnormalities in the brain parenchyma in six patients, dilated cortical veins in seven, venous pouches in four with type IV DAVF and enlargement of the superior ophthalmic vein in three patients with DAVF of the cavernous sinus. However, it showed none of the fistula sites and did not allow reliable identification of feeding arteries. 3D PC MRA enabled identification of the fistula and enlarged feeding arteries in six cases each. Stenosis or occlusion of the dural sinuses was detected in six of eight cases on 3D PC MRA with low velocity encoding. In six patients with type II DAVF phase reconstruction of 2D PC MRA demonstrated flow reversal in the dural sinuses or superior ophthalmic vein. Received: 14 May 1998 Accepted: 15 December 1998     

MR imaging findings of intracranial dural arteriovenous fistulas: relations with venous drainage patterns

BACKGROUND AND PURPOSE: Venous drainage patterns are a major determinant of clinical outcome in intracranial dural arteriovenous fistula (DAVF) patients. In this study, we sought to identify MR imaging finding differences between DAVF types classified on the basis of venous drainage patterns. METHODS: Twenty-seven patients diagnosed as having DAVFs by conventional angiography were included. Medical records (n = 27), and MR imaging (n = 27) and MR angiography (MRA; n = 11) findings were retrospectively reviewed. MR imaging findings included flow void cluster, engorged ophthalmic vein/proptosis, white matter hyperintensity, intracranial hemorrhage, dilated leptomeningeal or medullary vessels, venous pouch, and leptomeningeal or medullary vascular enhancements. MRA findings included identifiable fistula, venous flow-related enhancement, and prominent extracranial vessels. Patients' presentations and MR imaging findings were compared among angiographic type I, II, and III cases (according to Borden's classification), and MRA findings were compared between cases with and without retrograde leptomeningeal venous drainage (RLVD). RESULTS: Patient presentations were aggressive in one (13%) of the type I cases, 5 (50%) of the type II cases, and 8 (100%) of the type III cases (P = .002). Aggressive presentations included hemorrhage, focal neurologic deficits, seizures, intracranial hypertension, and an altered mental status. MR images showed significantly higher frequencies of dilated leptomeningeal or medullary vessels in a higher type [0 in type I, 5 (42%) in type II, and 7 (100%) in type III], and of leptomeningeal or medullary vascular enhancements [0 in type I, 4 (33%) in type II, and 7 (100%) in type III]. By using MRA, fistulas were identified only in cases with RLVD (5 [83%]). Venous flow-related enhancement was present in 10 cases (91%). A sole false-negative case on MRA, as compared with conventional angiography, resulted from nonvisualization of the slow venous flow (8%). No false-positive fistula was found at the other intracranial sites in all cases. Overall, MRA assessment for DAVF was adequate for both fistula and venous flow-related enhancement in 10 cases (91%) and inadequate in a remaining case because of the fistular location out of field. CONCLUSION: MR imaging demonstration of leptomeningeal or medullary vascular dilation and enhancements may be associated with features that are considered predictors of a poor outcome and indicates a need for urgent therapy in intracranial dural AVF patients. MRA is a complementary tool for the identification of dural AVF with venous flow-related enhancement.     

MRI和MRA对烟雾病的诊断价值

目的：评价ＭＲＩ和ＭＲ血管成像（ＭＲＡ）在烟雾病中的诊断价值。材料与方法：回顾性分析２３例烟雾病患者的ＭＲＩ和ＭＲＡ资料，ＭＲＡ采用三维时间飞跃法。结果：２３例患者ＭＲＡ图像均有不同程度的颈内动脉分叉处的血管狭窄／闭塞，１８例基底节区异常网状的血管和１４例软脑膜侧支循环血管显示清晰。ＭＲＩ上显示了所有患者的脑实质改变和１５例颈内动脉分叉处的血管狭窄／闭塞改变，所有患者根据其ＭＲ上脑血管的改变均可做出正确的诊断。结论：ＭＲＡ结合ＭＲＩ能对烟雾病患者做出正确的诊断和较准确的分期，同时可用于烟雾病患者的随访检查和术后复查。     

小儿缺血性脑血管病的MRI及MRA诊断

目的 评价磁共振成像（MRI）及磁共振血管成像（MRA）对小儿缺血性脑血管病的诊断价值。方法 回顾性分析了42例小儿缺血性脑血管病患，年龄1.2-14岁，平均7.5岁，全部病例均以急性起病的运动，语言障碍为主要症状来诊，采用轴位T1，T2加权像，部分病例加做冠状位或矢状位成像，其中31例进行了时间飞跃（TOF）法MR血管成像。结果 本组共发现脑缺血8例，脑梗塞34例（其中腔隙梗塞22例，大面积梗塞12例），单支颅内动脉狭窄6例。多支动脉狭窄4例；单支动脉闭塞3例。多支动脉闭塞2例；MOYAMOYA病9例（其中3例可见脑底异常血管网）。4例图像上有运动伪影，但能达到诊断要求，全部病例中，MRI表现典型，能单独确诊36例，占85.7%，MRI与MRA相结合能确诊40例，达95.2%，其余2例仅用MRI及MRA不能明确诊断，需结合临床资料及经随访证实。结论 MRI结合MRA是小儿缺血性脑血管病的理想检查方法，可准确显示脑动脉的狭窄，闭塞性病变及其继发的脑缺血，梗塞病灶，对定性诊断具有重要价值。     

Gd-DTPA增强MR扫描对脑发育性静脉异常的诊断价值

目的 对比分析ＭＲＩ平扫、增强扫描及ＭＲＡ对脑发育性静脉异常（ｄｅｖｅｌｏｐｍｅｎｔａｌ ｖｅｎｏｕｓ ａｎｏｍａｌｙ,ＤＶＡ）的显示价值,以期提高ＭＲＩ对脑ＤＶＡ的检出率及诊断正确率。材料与方法 回顾分析１２例脑ＤＶＡ的ＭＲＩ平扫、增强扫描及其中４例的ＭＲＡ表现,分别评价其对ＤＶＡ的引流静脉、髓静脉的显示价值。结果 １２例１４个ＤＶＡ。ＭＲ平扫８个ＤＶＡ可见引流静脉显影,５个ＤＶＡ扩张髓静脉区有     

胎儿腹部异常的MRI诊断及评价

目的分析胎儿几种腹部异常的MRI表现,说明MRI在胎儿异常诊断中的重要补充作用。资料与方法对14例(12例经剖腹产或手术病理证实,2例随访观察)的胎儿腹部畸形的MRI表现进行研究。结果14例中5例为脐部畸形,其中3例为脐膨出,2例小型,囊内为大网膜及小肠成分;另1例为巨型,囊内容物为肝脏及肠腔;2例为腹裂,突出物为肠腔结构。2例为肠系膜囊肿,胎儿腹腔内见囊样占位灶,1例直径约5cm,另1例巨大,直径约10cm。1例为先天性肛门闭锁,MRI表现为全肠腔明显扩张。1例先天性巨结肠,以直肠扩张为主的肠腔扩张。1例为先天性十二指肠闭锁,MRI表现为胃泡明显扩张,胃泡右侧、肝脏下缘见囊样信号灶,呈双泡征表现。1例为环状胰腺、异位胰腺,MRI表现为十二指肠扩张,呈不全性梗阻改变。1例为肝脏囊肿,MRI表现为肝右叶前段包膜下囊性病灶,大小约3.1cm×2.7cm×2.4cm。1例为双肾轻度积水,MRI见双侧肾盂稍饱满,肾盏略增宽。1例为左侧膈疝,MRI见左侧胸腔内正常肺组织消失,呈混杂肠腔信号。结论MRI作为产科胎儿超声检查的一种重要补充方法,对病变多方位的显示具有较高价值,对临床诊断及治疗有重要意义。     

烟雾病的MRI和MRA诊断

分析和讨论烟雾病的ＭＲＩ和ＭＲＡ表现及其诊断意义。材料和方法：对９例烟雾病患者进行了ＭＲＩ和ＭＲＡ检查,其中２例进行了ＤＳＡ检查。结果：９例ＭＲＩ上,８例显示脑实质改变包括脑梗死５例,脑萎缩２例,脑室扩大１例。８例中４例显示异常血管流空现象。另１例脑内未见异常．ＭＲＡ均良好地显示了病变血管狭窄和闭塞现象,表现为多支、双侧受累,在大脑中动脉为主,与ＤＳＡ所见相仿。结论：ＭＲＩ结合ＭＲＡ可作为烟雾病诊     

非孔源性视网膜脱离MRI诊断价值及原因探讨

目的:分析MRI在非孔源性视网膜脱离的应用价值,并探讨其致病原因.方法:收集因未发现裂孔而行MRI检查的非孔源性视网膜脱离患者24例,其中男性14例,女性10例,年龄21～85岁,平均51.5岁.全部病例经手术病理、临床综合诊断和随访证实.24例患者均采用头线圈行MRI检查,其中21例MRI增强;然后分析MRI影像及其致病原因.结果:非孔源性视网膜脱离表现为眼球内异常信号灶,V形13例(54%),弧形8例(34%),条状2例(8%),片状1例(4%),近端均连向视盘.非孔源性视网膜脱离,I_1WI表现为中等或稍高信号,T_2WI多呈相对低信号,也可呈等或高信号;增强后无强化表现.致病原因包括脉络膜黑色素瘤11例,外伤所致玻璃体出血3例,瘢痕或机化3例,脉络膜血管瘤2例,转移1例,脉络膜脱离1例,Coat病1例,异物术后1例,先天小眼球1例.结论:MRI不仅显示非孔源性视网膜脱离的特征性表现,而且对可能的致病原因作出正确诊断.     

MR angiography of dural arteriovenous fistulas: diagnosis and follow-up after treatment using a time-resolved 3D contrast-enhanced technique

BACKGROUND AND PURPOSE: Digital subtraction angiography (DSA) is the method of reference for imaging of dural arteriovenous fistula (DAVF). The goal of this study was to analyze the value of different MR images including 3D contrast-enhanced MR angiography (MRA) with a high temporal resolution in diagnostic and follow-up imaging of DAVFs. MATERIALS AND METHODS: A total of 18 MR/MRA examinations from 14 patients with untreated (n=9) and/or treated (n=9) DAVFs were evaluated. Two observers assessed all MR and MRA investigations for signs indicating the presence of a DAVF, for fistula characteristics such as fistula grading, location of fistulous point, and fistula obliteration after treatment. All results were compared with DSA findings. RESULTS: On time-resolved 3D contrast-enhanced (TR 3D) MRA, the side and presence of all patent fistulas (n=13) were correctly indicated, and no false-positive findings were observed in occluded DAVFs (n=5). Grading of fistulas with this imaging technique was correct in 77% and 85% of patent fistulas for both readers, respectively. On T2-weighted images, signs indicative of a DAVF were encountered only in fistulas with cortical venous reflux (56%), whereas on 3D time-of-flight (TOF) MRA, most fistulas (88%) were correctly detected. In complete fistula occlusion, false-positive findings were encountered on both T2-weighted images and on TOF MRA images. CONCLUSION: In this study, TR 3D MRA proved reliable in detecting DAVFs and suitable for follow-up imaging. The technique allowed--within limitations--to grade DAVFs. Although 3D TOF MRA can depict signs of DAVFs, its value for follow-up imaging is limited.     

Dural arteriovenous fistulas: evaluation with MR imaging

The preangiographic diagnosis of cerebral dural arteriovenous fistula (DAVF) can be difficult. The magnetic resonance (MR) images of 12 patients with angiographically proved DAVF were evaluated to characterize the appearance of these lesions and to identify those patients at increased risk for complications. Patients with DAVF demonstrating venous occlusive disease are at higher risk for complications from the arterialized collateral venous system. This venous occlusive disease is demonstrated best at arteriography. The MR imaging appearance of dilated cortical veins without a parenchymal nidus is suggestive of a DAVF with veno-occlusive disease. Eight of the 12 patients in our series demonstrated this finding at angiography. Complications, including infarction and hemorrhage, were identified at MR imaging in eight patients with MR imaging evidence of veno-occlusive disease. At angiography 42% of these complications were not apparent. In one patient with a DAVF draining into an unobstructed right sigmoid sinus, results of MR study were normal. Although patients with DAVF without veno-occlusive disease may have normal findings at MR imaging, DAVF associated with veno-occlusive disease and dilated pial venous drainage can be documented on MR images. This subset of DAVF patients, many of whom were identified only at MR imaging, is at higher risk for complications due to veno-occlusive disease. These patients are believed to require more urgent therapy. MR imaging is useful in the pretherapeutic planning for patients with DAVF.