Temporal Clustering Analysis for Detection of Irregular Transient fMRI Activation

描述（由申请人提供）：本项目的总体目标是进一步开发和评估一种新型的非侵入性成像和分析方法，用于使用功能性磁共振成像（fMRI）检测和定位大脑活动的短暂、重复但不规则的变化。该方法，2dTCA，是基于一系列的功能磁共振成像图像的时间聚类分析（TCA），并将主要开发用于检测和定位局灶性癫痫发作间期的大脑活动。在拟议的工作中，2dTCA图像分析算法和fMRI成像协议将首先在人类受试者的对照研究中进行评估和验证，其中刺激的时间是已知的。然后，将在两组局灶性癫痫患者中同时进行脑电图（EEG）记录，（1）头皮EEG上有单侧发作放电的患者，和（2）头皮EEG上有双侧发作放电的患者。这些数据将用于确定由fMRI和2dTCA单独检测和定位的血氧反应、由fMRI和同步EEG识别的血氧反应以及头皮处的EEG活动之间的关系。此外，EEG模式的定量分析将用于识别可能启动并对应于2dTCA检测到的氧合反应的EEG信号特征。这项研究的最终结果将是（1）一种新颖的、临床上更实用的技术，用于检测和定位随机的、瞬态的BOLD信号，这将扩展用于检查发作间期的分析方法。癫痫中的（发作之间）活动，以及其他非自愿激活模型，如图雷特综合征中的抽搐和精神分裂症患者的幻觉，（2）对2dTCA检测癫痫发作间期活动及其与头皮EEG的关系有了更全面的认识。本研究为2dTCA和fMRI在癫痫发作病灶识别中的应用提供了全面的临床验证基础。如果成功的话，利用功能磁共振成像的空间定位能力的能力将可用于那些大多数临床站点，无法负担MRI兼容的EEG系统和使用它们所需的技术专长，以及对于那些缺乏足够的头皮EEG活动的患者，禁止使用同步EEG方法。

DESCRIPTION (provided by applicant): The overall goal of this project is to further develop and evaluate a novel, non-invasive imaging and analysis method for the detection and localization of transient, repeated, but irregular changes in brain activity using functional Magnetic Resonance Imaging (fMRI). The method, 2dTCA, is based on the Temporal Clustering Analysis (TCA) of series of fMRI images and will be developed primarily to detect and localize interictal brain activity in focal epilepsy. In the proposed work, the 2dTCA image analysis algorithms and fMRI imaging protocol will first be evaluated and validated in control studies in human subjects where the timing of the stimulus is known. The validated protocol will then be performed with simultaneous electroencephalogram (EEG) recordings in two cohorts of focal epilepsy patients, (1) those with unilateral ictal discharges on scalp EEG, and (2) those with bilateral ictal discharges on scalp EEG. These data will be used to determine the relationship between the blood oxygenation responses detected and localized by fMRI and 2dTCA alone, the blood oxygenation responses identified by fMRI and simultaneous EEG, and the EEG activity at the scalp. In addition, quantitative analyses of the EEG patterns will be used to identify features of the EEG signals that may be initiating and correspond to the 2dTCA detected oxygenation response. The ultimate outcomes of the proposed study will be (1) a novel and much more clinically practical technique for detection and localization of random, transient BOLD signals that would expand analysis methods for examining interictal (between seizure) activity in epilepsy, as well as other involuntary activation models such as tics in Tourette Syndrome and hallucinations in patients with schizophrenia, and (2) a more complete understanding of the epileptic interictal activity detected by 2dTCA and its relationship to scalp EEG. This study is the foundation of a comprehensive clinical validation in the use of 2dTCA and fMRI in the identification of the seizure focus in epilepsy. If successful, the ability to utilize the spatial localization capabilities of fMRI will be available to those majority of clinical sites that cannot afford MRI-compatible EEG systems and the technical expertise required to use them, and for those patients whose lack of sufficient activity on scalp EEG prohibits the use of the simultaneous EEG methods.