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.     

Subclinical albuminuria is linked to gray matter atrophy in type 2 diabetes mellitus

Objective

Microalbuminuria (MA), a marker of renal microvascular disease, is associated with brain atrophy and neurovascular changes in older adults with type 2 diabetes mellitus (DM). We evaluated the relationship between urine albumin-to-creatinine ratio (UACR) and regional brain volumes to determine whether subclinical albuminuria may indicate early structural brain changes in type 2 DM.

Materials/Methods

We studied UACR and brain volumes in 85 type 2 DM patients (64.8 ± 8.3 years) and 40 age-matched controls using 3D magnetization prepared rapid acquisition with gradient echo (MP-RAGE) MRI (magnetic resonance imaging) at 3 Tesla. The relationship between UACR and brain volumes was analyzed using the least square models.

Results

In DM patients, UACR ≥ 5 mg/g, UACR ≥ 10 mg/g and clinically significant MA (UACR ≥ 17 mg/g [males] and 25 mg/g [females]) were associated with lower gray matter (GM) volume in the frontal lobe (r²_adj = 0.2–0.4, P = 0.01–0.05) and UACR ≥ 5 mg/g was also related to global GM atrophy (r²_adj = 0.1, P = 0.04), independent of DM duration, glucose levels, HbA_1c and hypertension. For UACR ≥ 5 mg/g, a lower global GM volume was related to worse executive function (P = 0.04) in the DM group. No associations were found for UACR (< 5 mg/g) and controls.

Conclusions

Subclinical albuminuria (UACR ≥ 5 mg/g) is associated with lower GM volume that has clinical impact on cognitive function in older diabetic patients, and these relationships are independent of DM control and hypertension. Therefore, UACR levels may serve as an additional marker of DM-related brain structural changes.     

老年胼胝体压部FLAIR序列异常高信号发生机制的探讨

目的在磁共振液体衰减翻转恢复（FLAIR）序列图像，胼胝体压部出现高信号通常被认为是病理变化。本研究的目的是分析这种病理改变在老年患者中的发生率及其可能的病理机制，并综述该MR表现的鉴别诊断。方法回顾性复习132例疑诊神经系统疾病的患者（男56例，女76例，年龄9～90岁，平均59岁）的FLAIR序列图像。分别观察胼胝体压部、深部脑白质改变、梗死及脑萎缩的情况。结果在132例患者中，33例（平均年龄59岁）患者的FLAIR像上胼胝体压部可见异常高信号改变，这种异常改变与年龄、脑白质的异常、脑萎缩及认知障碍的表现显著相关。结论FLAIR像上胼胝体压部高信号在老年患者中是常见的表现，多见于有认知障碍的老年患者。其病理变化通常被称之为“脑白质疏松症”。了解该异常表现发生的机制及该表现的鉴别诊断可避免不必要的有创诊断和治疗。     

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。