PRE-SURGICAL APPLICATIONS OF FUNCTIONAL MRI IN EPILEPSY

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。脑外科手术对许多患有医学上难治性癫痫的人来说是一种有效的治疗方法。功能性脑绘图技术有可能通过识别具有认知疾病特别风险的患者，识别不应在手术中切除的重要脑组织，以及帮助识别应切除的异常、致癫痫的脑组织，来改善这种治疗的结果。然而，关于这些应用程序仍然存在许多未解决的问题。对于语言或记忆系统的定位，目前还没有被普遍接受的方案，这两个认知领域在癫痫手术中风险最大。目前尚不清楚，如果有的话，哪种定位方案能够可靠地识别颞叶前部或海马体前部的重要组织，而大多数癫痫切除手术都是在这些组织中进行的。目前还没有研究提供证据证明功能性脑绘图有助于减少认知能力下降或改善癫痫控制。本提案是为了继续一个正在进行的项目，为这些目的开发标准化和可靠的功能磁共振成像（fMRI）方法。第一个目标是最大限度地减少癫痫手术导致的语言和记忆衰退，这取决于手术前对这些处理系统关键部分的精确定位。第二个长期目标是尽量减少对颈动脉内阿巴比妥注射侵入性技术（Wada检测）在手术前认知定位和癫痫病灶识别方面的依赖。为了实现这些目标，我们将(1)评估两种fMRI语言制图方案和一种记忆制图方案，以预测前颞叶切除术（最常见的癫痫手术形式）后的语言和言语记忆衰退；(2)评估这些fMRI方案在颞叶癫痫患者中识别癫痫发作起源侧位的能力；(3)比较fMRI与Wada检验的预测能力。这些研究将首次对癫痫手术前脑功能测绘的临床有效性和实用性进行大规模和严格的评估。他们的成功完成将为使用这些技术来改善癫痫手术的结果奠定坚实的基础。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Brain surgery is an effective treatment for many individuals who suffer from medically intractable epilepsy. Functional brain mapping techniques have the potential to improve the outcome of this treatment by identifying patients at particular risk of cognitive morbidity, by identifying vital brain tissue that should not be removed at surgery, and by helping to identify abnormal, epileptogenic brain tissue that should be removed. There remain, however, many unresolved issues regarding these applications. There are as yet no generally-accepted protocols for localization of language or memory systems, the two cognitive domains at greatest risk from epilepsy surgery. It is not clear which mapping protocols, if any, reliably identify vital tissue in the anterior temporal lobe or anterior hippocampus, where the majority of epilepsy resections are performed. No studies have yet provided evidence that functional brain mapping helps to minimize cognitive decline or improve seizure control. This proposal is for continuation of an ongoing project to develop standardized and reliable functional magnetic resonance imaging (fMRI) methods for these purposes. The first goal is to minimize language and memory decline from epilepsy surgery, which depends on precise presurgical localization of the critical components of these processing systems. The second, longer-term goal is to minimize reliance on the invasive technique of intracarotid amobarbital injection (Wada testing) for presurgical cognitive mapping and seizure focus identification. To achieve these goals, we will (1) assess two fMRI language mapping protocols and one memory mapping protocol for predicting language and verbal memory decline after anterior temporal lobectomy, the most common form of epilepsy surgery; (2) assess the ability of these fMRI protocols to identify the side of seizure origin in patients with temporal lobe epilepsy; and (3) compare the predictive power of fMRI with that of the Wada test. These studies will constitute the first large-scale and rigorous assessments of the clinical validity and utility of presurgical functional brain mapping in epilepsy. Their successful completion will lay a firm foundation for use of these techniques to improve the outcome of epilepsy surgery.