弥散张量纤维束成像在脑肿瘤手术的应用

目的明确弥散张量纤维束成像(diffusiontensortractography,DTT)技术在脑肿瘤术前计划制定及术后评价中的作用。方法对16例经病理学证实的脑肿瘤患者在术前进行DTT,利用DTT软件包重建重要脑白质纤维束(包括锥体束、胼胝体和视放射),观察其与脑肿瘤的位置关系,据此制定合理的手术计划。术后再利用DTT评价手术对上述脑白质纤维束的影响。结果脑白质纤维束与脑肿瘤的位置关系可分为单纯移位、移位伴破坏和单纯破坏3种类型。12例累及锥体束,其中单纯移位1例(术后移位减轻)、移位伴破坏9例(术后移位减轻)和单纯破坏2例(术后无改善)。7例累及胼胝体,其中移位伴破坏3例(术后移位减轻)和单纯破坏4例(术后均无改善)。3例累及视放射,均为单纯移位(术后移位减轻)。结论DTT可在术前显示重要的脑白质纤维束与脑肿瘤的位置关系,有助于脑肿瘤患者术前计划的制定和手术效果的评价。

A Study of Diffusion Tensor Tractography in Patients with Brain Tumors

Objective To demonstrate the location of clinically eloquent white matter tracts with respect to cerebral tumors using diffusion tensor tractography (DTT) and to determine the role of this technique in neurosurgical planning and postoperative assessment. Methods Sixteen patients with pathologically proved brain tumors underwent diffusion tensor imaging prior to tumor excision. By using tractography software package, the vital white matter tracts (include pyramidal tract, corpus callosum and optic radiation) were reconstructed and the exact locations of the lesion with respect to clinically eloquent white matter tracts were observed in every patient. Then reasonable surgical plan was determined. After operation, the diffusion tensor imaging was performed again and associated white matter tracts were evaluated to investigate the effect of these structures by surgery. Results The relationships between tumors and white matter tracts could be divided into three types: simple displacement, displacement with disruption and simple disruption. Pyramidal tract was involved in 12 cases, 1 case was simple displacement, 9 cases were displacement with disruption and other 2 cases were simple disruption without any improvement. Corpus callosum was involved in 7 cases, three of them were displacement with disruption which reducing displacement after operation and other 4 cases were simple disruption without any improvement. Optic radiation was involved in 3 cases, all were simple displacement with reducing of displacement after operation. Conclusion Visualization of the exact location of vital white matter tracts with respect to cerebral tumors can be shown before operation by DTT.