移动磁体双室高场强术中磁共振成像系统在经蝶窦垂体腺瘤手术中的初步应用

目的 总结移动磁体双室高场强术中磁共振成像(iMRI)系统在经蝶窦垂体腺瘤手术中的初步经验.方法 共有28例垂体腺瘤患者行经蝶窦入路iMRI辅助下的手术.肿瘤大小1.60～7.27 cm,平均(3.37±0.65)cm.应用1.5T移动磁体双室设计的iMRI,其中14例联合使用神经导航系统,16例联合使用神经内镜.结果 27例经鼻蝶窦手术,1例经口鼻蝶安手术.28例经蝶窦垂体腺瘤手术中,13例iMRI发现肿瘤残留,其中3例巨大垂体腺瘤患者,由于肿瘤侵犯海绵窦包绕颈内动脉,虽经iMRI证实海绵窦内有肿瘤残留,但未勉强进一步切除.其余10例经iMRI证实垂体腺瘤均完全切除.未发生与iMRI相关的并发症或安全事故.结论 移动磁体双室高场强iMRI系统能够在术中获得高质量的影像,为术中实时判断垂体腺瘤切除程度提供了客观依据,提高了垂体腺瘤的全切率.     

高场强术中磁共振成像对脑胶质瘤全切率的影响及其评估

目的 探讨高场强术中磁共振成像(iMRI)对脑胶质瘤手术全切率的影响及其意义.方法 自2009年2月至6月应用高场强iMRI施行脑胶质瘤切除术40例.运用术中影像数据对胶质瘤体积及全切率做回顾性分析.结果 术中第1次行iMRI扫描仅10例胶质瘤完全切除,30例肿瘤仍有残留,23例行进一步切除,其中21例胶质瘤最终全切除.最终肿瘤的伞切率从25%提高到78%,残存肿瘤的体积也明显下降.结论 高场强iMRI的应用显著提高脑胶质瘤手术的全切率.     

术中磁共振成像技术的现状与展望

术中磁共振成像(iMRI)可三维实时颅脑成像,纠正神经导航术中脑移位误差,精确引导手术进程,提高临床疗效和安全性.历经十余年,iMRI硬件设备和软件技术迅猛发展,从MRI诊断事进入神经外科手术室;从固定磁体向可移动磁体;从低场强向高场强;从结构影像导航向功能影像导航.     

低场强术中磁共振成像在经鼻蝶窦垂体大腺瘤显微手术中的应用

目的 探讨低场强术中磁共振成像(iMRI)在经鼻蝶窦垂体大腺瘤显微手术中的应用.方法 在82例垂体大腺瘤的经鼻蝶窦显微手术中,采用0.15T iMRI系统进行术中实时引导.以术后早期高场强MRI为标准对照,定量分析iMRI的成像准确性,并就低场强iMRI对肿瘤切除程度和治疗结果 的影响进行分析.结果 在iMRI的辅助下,82例垂体大腺瘤的全切率从61.0%提高到81.7%.低场强iMRI的成像准确率达86.6%,但对于侵犯鞍旁结构的肿瘤的成像准确率明显低于其他类型垂体大腺瘤的成像准确率(53.3%vs 94.0%,P<0.001).结论 iMRI导航技术的应用,'为经蝶窦垂体大腺瘤手术进程的动态引导及手术结果 的实时判断提供了客观的依据,提高了肿瘤的全切率及手术的精确性与安全性.     

高场强术中磁共振对脑胶质瘤切除程度及手术策略的影响

目的 评价高场强术中磁共振(iMRI)对脑胶质瘤手术切除程度及手术策略的影响.方法 解放军总医院神经外科自2009年10月至2010年6月将高场强iMRI系统应用于胶质瘤切除术患者106例,术前了解术者的切除意图(全切、次全切、大部切除),术前1 d患者常规行MRI扫描,应用影像数据和软件计算术前肿瘤体积,术中常规使用神经导航手术,依据术者的需求采集影像.必要时行iMRI扫描计算术中残余肿瘤体积和肿瘤体积切除百分比,分析使用iMRI对肿瘤切除程度、手术策略的影响.结果 术前计划全切48例,次全切41例,大部切除17例.术中第一次扫描示42例(39.6%)完全切除,64例(60.4%)仍有残留,其中25例由于肿瘤与重要功能区或重要传导束紧邻而未作进一步切除,其余39例(36.8%)改进手术策略,标记出残留肿瘤后进一步手术,25例(23.6%)胶质瘤最终全切除,肿瘤体积切除百分比由(76.5±20.5)%提高到(94.2±8.7)%,差异有统计学意义(U=2.000,P=0.000);最终实际全切67例,次全切25例,大部切除14例,全切率有所提高.106例患者平均肿瘤体积切除百分比由第一次扫描时的(86.3±20.2)%提高到最终扫描时的(93.6±12.4)%,差异有统计学意义(U=4.000,p=0.000).结论 高场强iMRI的应用可显著提高脑胶质瘤的切除程度,改进手术策略.

Abstract：

Objective To evaluate the impact of high-field intraoperative magnetic resonance imaging (iMRI) on extension of resection and surgical strategy modification for glioma surgery. Methods One hundred and six patients, admitted to our hospital from October 2009 to June 2010, were performed glioma resections with the help of high-field iMRI. Questionnaires were filled and collected prospectively to record the surgeons' intention on the extent of resection (EoR) and the intra-operative estimation of EoR before every iMRI scan. The scan imagings were collected based on the request of the surgeon, and the percentage of tumor removal was calculated according to the iMRI data. The impact of iMRI on the tumor EoR and modification of surgical strategy was then evaluated. Results Preoperatively, 48 patients were intended to achieve total tumor removal, 41 sub-total tumor removal, and 17 partial removal. The first intraoperative MRI scan revealed that 42 (39.6%) patients achieved complete resection, while residual tumors were depicted in 64 (60.4%).Further tumor resections were performed in 39 patients (36.8%), but the other 25 patients could not perform further resection for their tumors were closely neighbored to the important functional region or important tracts. Finally, in the whole cohort, the percentage of tumor resection volume was increased from (76.5±20.5)% to (94.2±8.7)%, with significant differences (U=2.000, P=0.000); 67 patients got complete removal, 25 sub-total removal and 14 partial removal; The total removal rate was significantly increased from 45.3% (48/106) to 63.2% (67/106): the average percentage of tumor resection volume in the second time of scan ([93.6±12.41%) was obviously increased as compared with that in the first scan ([86.3±20.21%, U=4.000, P=0.000). Conclusion High-field iMRI may increase the extent of glioma resection, and has significant impact on the intraoperative modification of the surgical strategy.     

低场强术中磁共振BOLD导航在脑功能区胶质瘤术中的应用

目的 探讨低场强术中磁共振(iMRI)融合术前采集血液氧饱和水平检测功能成像(BOLD)功能导航的可行性和应用价值.方法 48例脑皮层功能区的胶质瘤患者随机分组,试验组用术前高场强的BOLD影像与术中iMRI解剖影像融合,对照组将高场强的BOLD与术前高场强MRI解剖影像融合,分别导航手术.两组均采用术中电生理来验证BOLD功能区定位的准确性并随访.结果 试验组BOLD敏感性73.3%,特异性83.3%;对照组BOLD敏感性75.5%,特异性81.2%,差异无统计学意义.试验组肿瘤全切率为85.1%,对照组77.8%,差异有统计学意义(P:0.012);试验组术后功能改善或保持率为80.8%,对照组83.3%,差异无统计学意义.结论 低场强iMRI与术前BOLD功能导航手术可实时提供病灶与功能区可视化解剖信息,有助于提高肿瘤切除率,降低术后致残率.     

术中磁共振影像神经导航手术的临床初步应用

目的:探讨术中核磁共振影像神经导航(intraoperative MR image-based neuronavigation)技术在神经外科手术的意义。方法:应用PoleStarN-20术中磁共振成像(iMRI)神经导航系统施行神经外科手术22例。对其临床资料、iMRI情况,及其对手术进程和手术结果的影响进行分析。结果:22例手术中,经鼻-蝶垂体瘤切除术10例,幕上开颅肿瘤切除术10例,幕下开颅肿瘤切除术2例。iMRI扫描次数从2～5次不等,平均2.6次。共有9例术中扫描发现有肿瘤残留,其中8例(36.4%),需做进一步的切除,最终肿瘤的全切率从60%提高到86.4%。无与iMRI相关的并发症。结论:iMRI神经导航技术的应用,为神经外科手术入路的选择、皮肤切口的设计、手术进程的指导及手术结果的实时判断提供了客观的依据,从而在提高手术的精确性和安全性的同时,提高了颅脑肿瘤的全切率。     

低场强术中磁共振环境下的神经电生理监测

目的 探讨低场强iMRI环境下神经电生理监测(IOM)的操作特点与临床初步体会.方法 分析9例功能区脑肿瘤10M及iMRI的联合应用情况.采集IOM基线,与iMRI环境下的波形比较;记录iMRI影像畸变及电刺激相关不良事件.术后早期复查MRI评估肿瘤切除隋况.结果 9例行IOM均获得稳定波形.1例前置放大器冈磁电效应损坏,未观察到热损伤或电极移动损伤.iMRI 7例局部信号缺失;3例发现肿瘤残余.术后随访MRI 7例全切,2例次全切除,与iMRI判断一致.结论 低场强iMRI环境下,IOM可获得稳定波形.二者联合应用,有助于病变安全切除.     

术中磁共振影像神经导航辅助经鼻-蝶垂体瘤切除术(附42例分析)

目的探讨术中磁共振影像(iMRI)神经导航技术在经鼻-蝶垂体瘤切除手术中的应用。方法在PoleStar N20 iMRI神经导航系统辅助下施行经鼻-蝶垂体瘤切除术42例。对临床资料、iMRI成像情况及其对手术进程和手术结果的影响等进行分析。结果术中扫描2～5次,平均(2.5±0.87)次。术中扫描发现肿瘤残留13例,其中2例因肿瘤包绕颈内动脉未进一步切除,另11例进一步切除后,达到影像学肿瘤全切除6例,次全切除5例。最终肿瘤的全切除率从69.0%提高到83.3%。无与iMRI相关的并发症。结论经鼻-蝶垂体瘤切除术中应用iMRI神经导航技术,为手术进程的指导及手术结果的实时判断提供了客观依据,从而提高了肿瘤的全切除率。     

3.0T 术中磁共振实时影像功能导航联合术中神经电生理监测技术在岛叶胶质瘤手术中的应用

目的评价3.0 T术中磁共振成像(intraoperative magnetic resonance imaging,iMRI)联合弥散张量成像(diffusion tensor imaging,DTI)锥体束示踪导航及术中神经电生理监测(intraoperative neurophysiologicalmonitoring,IONM)技术在各种累及岛叶的胶质瘤切除手术中的应用价值。方法 2010年9月至2011年6月以3.0 T iMRI数字一体化神经外科手术中心为平台,在iMRI功能导航结合IONM下对18例累及岛叶的胶质瘤实施切除手术。其中对10例主侧半球肿瘤采用唤醒麻醉下术中直接皮质电刺激进行语言区定位。对所有18例岛叶胶质瘤,术中均采用DTI导航结合术中连续经皮质刺激运动诱发电位和皮质下电刺激进行锥体束定位。结果通过iMRI实时扫描,18例患者中有13例发现肿瘤残留,其中6例在iMRI实时影像导航下获得了进一步切除,使肿瘤的影像学全切除率从5/18提高至9/18。经Fisher检验,iMRI前、后的肿瘤切除率(包括全切除及次全切除)具有统计学意义(P=0.046)。9例因DTI导航或IONM提示切缘临近功能皮质或深部锥体束,而未强求全切除。10例主侧半球肿瘤患者中,术后近期(1周内)出现一过性语言功能障碍5例,随访至术后1个月,语言功能均恢复到术前水平或以上;18例患者中3例术后近期出现肢体运动功能障碍,随访至术后1个月,其中2例完全恢复。总体术后1个月的神经功能障碍仅1例。无iMRI及IONM相关的并发症发生。结论应用3.0 T iMRI术中实时影像导航联合DTI锥体束示踪成像技术及IONM技术有助于最大程度地安全切除岛叶胶质瘤。     

Intraoperative visualization for resection of gliomas: the role of functional neuronavigation and intraoperative 1.5 T MRI

OBJECTIVE: To investigate how functional neuronavigation and intraoperative high-field magnetic resonance imaging (MRI) influence glioma resection. METHODS: One hundred and thirty-seven patients [World Health Organization (WHO) grade I: 20; II: 19; III: 41; IV: 57] underwent resection for supratentorial gliomas in an operative suite equipped with intraoperative high-field MRI and microscope-based neuronavigation. Besides standard anatomical image data including T1- and T2-weighted sequences, various functional data from magnetoencephalography (n=37), functional MRI (n=65), positron emission tomography (n=8), MR spectroscopy (n=28) and diffusion tensor imaging (n=55) were integrated in the navigational setup. RESULTS: Intraoperative MRI showed primary complete resection in 27% of all patients (I: 50%; II: 53%; III: 2%; IV: 28%). In 41% of all patients (I: 40%; II: 26%; III: 66%; IV: 28%) the resection was extended owing to intraoperative MRI increasing the percentage of complete resections to 40% (I: 70%; II: 58%; III: 17%; IV: 40%). Integrated application of functional navigation resulted in low post-operative morbidity with a transient new neurological deficit in 10.2% (paresis: 8.8% and speech disturbance: 1.4%) decreasing to a permanent deficit in 2.9% (four of 137 patients with a new or increased paresis). CONCLUSIONS: The combination of intraoperative MRI and functional navigation allows safe extended resections in glioma surgery. However, despite extended resections, still in the majority of the grade III and IV gliomas no gross total resection could be achieved owing to the extension of the tumor into eloquent brain areas. Intraoperative MRI data can be used to localize the tumor remnants reliably and compensate for the effects of brain shift.     

Optimizing epilepsy surgery with intraoperative MR imaging

PURPOSE: The surgical treatment of medically intractable temporal lobe epilepsy includes the resection of temporal lobe structures. Although the reported seizure-free outcomes are highly variable, there is growing evidence that the extent of resection of the mesiotemporal lobe directly correlates with seizure control. METHODS: A moveable, high-field intraoperative magnetic resonance (MR) system was used to monitor and optimize the resection of the amygdala and hippocampus in 14 epilepsy patients. Fourteen patients with intractable seizures of temporal lobe origin underwent standard preoperative investigations including MR imaging, EEG telemetry, single-photon emission computed tomography, and neuropsychologic and sodium amytal testing. Anterior temporal lobectomy was performed on 10 patients, whereas four were treated with selective amygdalohippocampectomy. Intraoperative electrocorticography was applied as required. For all procedures, the objective was to resect the amygdala completely, and hippocampus to the posterior margin of the brainstem. RESULTS: Interdissection intraoperative MR imaging taken when optimal resection was thought to have been achieved revealed residual unresected amygdala or hippocampus in seven of 14 patients. An unexpected acute hematoma was found in one patient. At 17 months' follow-up, 13 (93%) of 14 patients are seizure free or have significantly improved seizure control. CONCLUSIONS: The mobile high-field intraoperative MR system provides high-resolution images without restriction on surgical instruments or techniques. The ability to identify and resect residual mesial temporal lobe targets before craniotomy closure is of potentially tremendous value in optimizing seizure control.     

Inflammation high-field magnetic resonance imaging

Multiple sclerosis (MS) is the most common inflammatory demyelinating disorder of the central nervous system (CNS). MS has been subject to high-field magnetic resonance (MR) imaging research to a great extent during the past years, and much data has been collected that might be helpful in the investigation of other inflammatory CNS disorders. This article reviews the value of high-field MR imaging in examining inflammatory MS abnormalities. Furthermore, possibilities and challenges for the future of high-field MR imaging in MS are discussed.     

A MRI-compatible system for whisker stimulation

We describe here a system for whisker stimulation designed for functional studies in high-field magnetic resonance imaging (MRI) environments. This system, which incorporates real-time optical monitoring of the vibration stimulus, can generate well-controlled and reproducible whisker deflections with amplitudes up to 2mm and frequencies up to 75 Hz, suitable for functional magnetic resonance imaging (fMRI) studies of animals. Whiskers on either or both sides of the head can be stimulated selectively during fMRI experiments without removing the subject from the magnet. With a user-friendly graphical interface of a computer, a user can conveniently control both the whisker vibration and gating of the MR imager, and synchronize the stimulation with the fMRI acquisition to ensure precise timing of the stimulus presentation. This whisker stimulation system should facilitate a wide variety of fMRI investigations of the neural systems mediating sensory information from the whiskers.     

Magnetic resonance imaging in partial complex epilepsy

The yield of magnetic resonance (MR) imaging was investigated in 30 patients with partial complex epilepsy, and the results were compared with those of computed tomography (CT). Magnetic resonance imaging and CT disclosed focal cerebral abnormalities in 13 (43%) and eight (26%) patients, respectively. Two additional focal temporal lesions were identified by double-dose CT scanning, increasing the yield of CT to 33%. Magnetic resonance images were abnormal in all patients with focally abnormal CT scans, and in four patients (50%) they defined the extent of the temporolimbic lesions better than did the CT scans. Two of these patients had gliomas. In addition, MR images were focally abnormal in 85% of the patients in whom scalp electroencephalograms showed focal ictal discharges. These data indicate that MR imaging is more informative than CT in partial complex epilepsy.     

Brain surface reformatted imaging (BSRI) in surgical planning for resections around eloquent cortex

Background Resective surgeries around eloquent areas challenge neurosurgeons and neuroimaging professionals due to difficulties to find anatomic references during surgery. Advances in magnetic resonance (MR) may prevent such deficits and provide information for accurate surgical planning. However, most of these techniques are expensive and not feasible in most centers. Using brain surface reformatted imaging (BSRI) of 3-D MR images, we sought to obtain data for surgical planning in patients with lesions around the motor cortex.Methods Thirteen patients with lesions around the eloquent areas and considered for resective surgery were evaluated. Patients had different ages with tumors and malformative lesions. They were scanned in a 1.5-T Siemens magnet with volumetric sequence after injection of Gadolinium. Postprocessing was done in an auxiliary console using MRI station software. We performed reformatting as described by Hattingen et al. [J Neurosurg 102:302–310, 2005] and used fixed skull and vascular structures as anatomical references. Distances to the reference points were measured to allow surgical planning and locate sites for cortical stimulation. Patients were also studied by blood-oxygen-level-dependent functional magnetic resonance imaging to locate the hand area before the surgical procedure. All patients had cortical stimulation during the resective procedure or chronic electrode stimulation before surgery.Results There was concordance between data from functional and structural data. In one case, partial resection was performed due to the high risk of severe deficits. Even in this case, there were clinical improvements and no additional deficits were observed.Conclusion BSRI may be a useful tool for surgical planning around eloquent areas. It can reduce surgical time and morbidity and showed correlation with functional studies. Added to this is the low cost and feasibility in most centers that have standard MR scanners with Multiplanar Reformatting software.     

3 TESLA MR imaging in adults with focal onset epilepsy

Objective

The finding of cerebral epileptogenic lesions in magnetic resonance (MR) has demonstrated to be a relevant prognostic factor for potential surgical candidates. In a series of consecutive adults with focal onset epilepsy, we investigated the yield of 3 T MR imaging for detecting epileptogenic cerebral lesions.

Materials and methods

We prospectively recruited 161 adult patients with a diagnosis of focal epilepsy, all of whom underwent standardized MR imaging study performed with a 3 T magnet.

Results

Lesion-related epilepsy was observed in 48% of patients, and 12% of cryptogenic patients showed subtle or non-specific lesions related to the epileptogenic source. The most common findings were focal cortical dysplasia and vascular lesions, followed by mesial temporal sclerosis, tumors, and scars from previous cerebral injuries. Patients older than 72 years were more likely to have vascular epilepsy.

Conclusions

Diagnostic assessment using a standardized 3 T MR imaging protocol for focal-onset epilepsy detects lesions in nearly half the patients. Our results indicate that elders with focal epilepsy should be searched for vascular lesions.