Rohde V, Rohde I, Thiex R, Küker W, Ince A, Gilsbach J M
Department of Neurosurgery, Aachen University of Technology (RWTH), Pauwelsstrasse 30, 52074 Aachen, Germany.
Surg Neurol. 2001 Oct;56(4):266-74; discussion 274-5. doi: 10.1016/s0090-3019(01)00594-8.
Intraoperative magnetic resonance imaging (MRI) for guided biopsy or microsurgical resection of intracranial lesions is gaining broader acceptance. It is not known whether intraoperative MRI has the potential to detect hemorrhagic complications of these surgical procedures, because scientific research has so far focussed on the signal characteristics of less acute clots. It is the objective of this experimental study to investigate whether MRI can visualise intracerebral blood within minutes after its occurrence.
In 26 pigs, a frontal hematoma was produced by injecting autologous blood. Twenty pigs underwent MRI 30 minutes after injection, and 6 pigs within the first 10 minutes. MRI scans were performed on a 1.5T system. T1-weighted spin echo (SE), T2-weighted turbo spin echo (TSE), T2-weighted fluid attenuated inversion recovery (FLAIR), and T2-weighted gradient echo (GE) images were acquired. Depending on the differences of the signal intensities of the hematoma and the surrounding brain, the detectability of the hematoma was rated as good, fair, or poor.
None of the induced hematomas were rated to be clearly visible on T1-weighted sequences. Six of the 26 hematomas (23%) were easily detectable on FLAIR sequences, 18 hematomas (69%) on T2-weighted TSE sequences, and 23 hematomas (88%) on the T2-weighted GE sequences.
Extravasated blood can be identified with a high reliability within minutes after its occurrence on MRI provided that T2-weighted GE sequences are used for imaging. In conclusion, intraoperative MRI is not only of value for guidance of neurosurgical procedures, but also for immediate detection of hemorrhagic complications.
术中磁共振成像（MRI）用于颅内病变的引导活检或显微手术切除正得到更广泛的认可。目前尚不清楚术中MRI是否有潜力检测这些手术的出血并发症，因为迄今为止的科学研究主要集中在不太急性的血凝块的信号特征上。本实验研究的目的是调查MRI能否在脑内出血发生后几分钟内显示出血液。
对26头猪通过注射自体血制造额叶血肿。20头猪在注射后30分钟接受MRI检查，6头猪在最初10分钟内接受检查。在1.5T系统上进行MRI扫描。采集T1加权自旋回波（SE）、T2加权快速自旋回波（TSE）、T2加权液体衰减反转恢复（FLAIR）和T2加权梯度回波（GE）图像。根据血肿与周围脑组织信号强度的差异，将血肿的可检测性评为良好、中等或较差。
在T1加权序列上，所有诱发的血肿均未被评为清晰可见。26个血肿中有6个（23%）在FLAIR序列上易于检测，18个血肿（69%）在T2加权TSE序列上易于检测，23个血肿（88%）在T2加权GE序列上易于检测。
如果使用T2加权GE序列进行成像，外渗血液在其发生后几分钟内即可在MRI上以高可靠性被识别。总之，术中MRI不仅对神经外科手术的引导有价值，而且对出血并发症的即时检测也有价值。
