Nataf F, Ghossoub M, Missir O, Merienne L, Roux F X, Meder J F, Trystram D, Schlienger M, Merland J J, Chodkiewicz J P
Department of Neurosurgery, Centre Hospitalier Sainte-Anne, Paris, France.
Stereotact Funct Neurosurg. 1997;69(1-4 Pt 2):143-6. doi: 10.1159/000099866.
Radiosurgery of cerebral arteriovenous malformations (cAVM) can induce parenchymal changes seen on MRI. The purpose of this study was to classify these changes and to correlate them to clinical outcome and obliteration of the cAVM. 142 patients with cAVM underwent radiosurgery with a linear accelerator between 1994 and 1995. 60 clinical records, MR images, and postradiation angiograms were reviewed. Signal abnormalities and contrast enhancements were correlated with clinical deterioration and size decrease of the AVM. The Spearman nonparametric test was used for statistical correlation. MR findings allowed to differentiate between four grades: grade 1 = no parenchymal changes; grade 2 = hypersignal on T2-weighted sequences, grade 3 = grade 2 + contrast enhancement on T1-weighted sequences; grade 4 = grade 3 + central hyposignal (necrosis-like) + peripheral hyposignal surrounding the AVM on T1-weighted sequences. Grade 4 was significantly related (p < 0.001) to clinical deterioration (deficit, seizures, increased intracranial pressure). All grade 4 patients, and only them, had clinical symptoms. Most of these symptoms regressed with corticoid treatment. Grade 4 was also related to the proportion of obliteration of the cAVM at 1 year after radiotherapy: mean proportion of obliteration was 12.5% for grade 2, 25% for grade 3 and 82.2% for grade 4 (p < 0.01). The size of T2-weighted MR images was related to clinical symptom appearance (p < 0.001). Finally, contrast enhancement was not predictive of the occurrence of the clinical symptoms. This proposed classification allows one to differentiate between the various MR images, and seems to predict clinical complications and response to radiotherapy of the cAVM.
脑动静脉畸形（cAVM）的放射外科治疗可引起MRI上可见的实质改变。本研究的目的是对这些改变进行分类，并将它们与临床结果及cAVM的闭塞情况相关联。1994年至1995年间，142例cAVM患者接受了直线加速器放射外科治疗。回顾了60例患者的临床记录、MR图像和放射治疗后的血管造影。信号异常和强化与临床恶化及AVM大小减小相关。采用Spearman非参数检验进行统计学相关性分析。MR表现可分为四级：1级 = 无实质改变；2级 = T2加权序列上高信号；3级 = 2级 + T1加权序列上强化；4级 = 3级 + T1加权序列上中央低信号（类坏死）+ AVM周围外周低信号。4级与临床恶化（神经功能缺损、癫痫、颅内压升高）显著相关（p < 0.001）。所有4级患者，且只有他们有临床症状。这些症状大多经皮质类固醇治疗后消退。4级也与放疗后1年cAVM的闭塞比例相关：2级的平均闭塞比例为12.5%，3级为25%，4级为82.2%（p < 0.01）。T2加权MR图像的大小与临床症状出现相关（p < 0.001）。最后，强化不能预测临床症状的发生。这种提出的分类方法可区分各种MR图像，似乎能预测cAVM的临床并发症及对放疗的反应。
