The Usefulness of the Ivy Sign on Fluid-Attenuated Intensity Recovery Images in Improved Brain Hemodynamic Changes after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis in Adult Patients with Moyamoya Disease

Objective

MR perfusion and single photon emission computerized tomography (SPECT) are well known imaging studies to evaluate hemodynamic change between prior to and following superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis in moyamoya disease. But their side effects and invasiveness make discomfort to patients. We evaluated the ivy sign on MR fluid attenuated inversion recovery (FLAIR) images in adult patients with moyamoya disease and compared it with result of SPECT and MR perfusion images.

Methods

We enrolled twelve patients (thirteen cases) who were diagnosed with moyamoya disease and underwent STA-MCA anastomosis at our medical institution during a period ranging from September of 2010 to December of 2012. The presence of the ivy sign on MR FLAIR images was classified as Negative (0), Minimal (1), and Positive (2). Regions were classified into four territories: the anterior cerebral artery (ACA), the anterior MCA, the posterior MCA and the posterior cerebral artery.

Results

Ivy signs on preoperative and postoperative MR FLAIR were improved (8 and 4 in the ACA regions, 13 and 4 in the anterior MCA regions and 19 and 9 in the posterior MCA regions). Like this result, the cerebrovascular reserve (CVR) on SPECT was significantly increased in the sum of CVR in same regions after STA-MCA anastomosis.

Conclusion

After STA-MCA anastomosis, ivy signs were decreased in the cerebral hemisphere. As compared with conventional diagnostic modalities such as SPECT and MR perfusion images, the ivy sign on MR FLAIR is considered as a useful indicator in detecting brain hemodynamic changes between preoperatively and postoperatively in adult moyamoya patients.     

Arterial spin labeling hyperperfusion in Rasmussen's encephalitis: Is it due to focal brain inflammation or a postictal phenomenon?

Background and purpose

The study evaluated the utility of arterial spin labeling (ASL) perfusion imaging in Rasmussen's encephalitis (RE).

前庭神经炎患者内耳3D-FLAIR MRI特点与前庭功能相关性分析北大核心CSCD

目的初步研究前庭神经炎(VN)患者内耳三维快速液体衰减反转恢复磁共振成像(3D-FLAIR MRI)特点,探讨VN可能的发病部位,同时与前庭功能结合进行相关性分析。方法收集山东大学山东省耳鼻喉医院眩晕疾病科2019年12月至2020年10月收治的36例VN患者的临床资料,其中男18例,女18例;年龄25~71岁,平均44.1岁;均为单侧发病,患侧为左耳17例,右耳19例。根据内耳3D-FLAIR MRI结果分为强化组及非强化组(健侧作为正常对照组),比较2组患者前庭功能检查结果,应用SPSS 19.0软件进行统计学处理,分析患者前庭功能与内耳3D-FLAIR特点的关系。结果36例中发现3D-FLAIR异常强化31例(86.1%),其中前庭神经及前庭终器同时强化14例,单纯前庭上神经强化8例,单纯前庭终器强化7例,单纯耳蜗强化2例。观察前庭神经异常强化显示:前庭上神经强化21例,前庭上、下神经强化1例。5例内耳3D-FLAIR未见异常。根据前庭功能结果分析显示全前庭神经受累19例(52.8%),单纯前庭上神经受累16例(44.4%),单纯前庭下神经受累1例(2.8%)。内耳3D-FLAIR强化组31例患者半规管轻瘫值60.81±3.49,非强化组5例患者半规管轻瘫值34.12±7.37,差异有统计学意义(t=-2.898,P<0.01)。结论内耳3D-FLAIR MRI可以为临床提供可视的影像证据,考虑VN的病变部位不仅在前庭神经,还包括前庭终器。内耳3D FLAIR异常强化的患者其前庭功能损伤更显著。     

脑梗死FLAIR与介入治疗疗效的相关性研究

目的通过观察脑梗死患者核磁共振成像(MRI)液体衰减反转回复序列(FLAIR)的多态性,探讨其与介入治疗疗效的相关性,为临床介入治疗探索一种新的适应证。方法对应用FLAIR技术检查的100例脑梗死患者,观察介入治疗后的疗效。结果FLAIR显示高信号而常规快速自旋回波T2加权像(T2WI)未显示或部分显示病灶的病例疗效好;FLAIR与T2WI均显示高信号亦有疗效;FLAIR显示混杂信号,T2WI显示高信号疗效差;FLAIR显示低信号,而T2WI显示高信号无疗效。结论FLAIR技术可早期显示梗塞病灶,有利于早期动脉溶栓治疗。     

磁共振FLAIR技术在脑挫裂伤诊断中的应用价值

目的探讨MRI快速液体抑制反转恢复脉冲序列(FLAIR)在脑挫裂伤诊断中的应用价值。方法回顾性分析36例脑挫裂伤患者的MR表现,比较FLAIR、T2WI/TSE及T1WI/SE三种脉冲序列诊断脑挫裂伤病变范围和蛛网膜下腔出血的结果。结果在36例脑挫裂伤患者中,16例FLAIR对病灶周围水肿范围以及病灶对邻近结构压迫的诊断较T2WI准确,12例FLAIR较T2WI显示出更多位于皮质功能区和灰白质交界区的较小病灶。29例经腰穿和CT检查证实合并有蛛网膜下腔出血的患者中,FLAIR序列均明确诊断,而T1WI仅有11例(37.9%)能作出明确诊断。结论FLAIR对诊断脑挫裂伤的病变范围和位于重要功能区的较小病灶以及是否合并有蛛网膜下腔出血具有重要的临床价值。     

磁共振FSE及FastFLAIR序列对脑内小缺血病灶的诊断价值

目的：探讨FSE序列及快速FLAIR序列对脑内小缺血病灶的诊断价值。方法：随机抽取同时行FSE和FLAIR序列检查的腔隙性脑缺血病变60例，由两名有经验的MR医师采用双盲法分别对FSE及FastFLAIR序列图像进行分析，并对疾病作出分级诊断。结果：病变于FSE序列呈略高信号，边界欠滑，于FLAIR序列表现为较高信号，边界较清楚：部分在FSE序列表现为可疑病灶或未能显示的病灶，在FLAIR序列能较清楚显示。经过统计学分析，可以认为控制医生这一分层因素影响后，应用FLAIR序列诊断脑梗塞的效能高于应用FSE序列进行诊断。结论：FastYLAIR序列在显示脑内缺血性病灶方面较FSE序列有更高的敏感性，应作为颅脑MRI检查的常规序列。