Temporal Clustering Analysis for Detection of Irregular Transient fMRI Activation

描述(申请人提供)：该项目的总体目标是进一步开发和评估一种新的、非侵入性的成像和分析方法，用于使用功能磁共振成像(FMRI)检测和定位大脑活动的瞬时、重复但不规则的变化。这种名为2dTCA的方法基于对一系列fMRI图像的时间聚类分析(TCA)，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。在这项拟议的工作中，2dTCA图像分析算法和fMRI成像协议将首先在已知刺激时间的人类受试者对照研究中进行评估和验证。然后，将在两组局灶性癫痫患者中同时进行脑电(EEG)记录，(1)在头皮EEG上有单侧发作性放电的患者，(2)在头皮EEG上有双侧发作性放电的患者。这些数据将被用来确定fMRI和2dTCA单独检测和定位的血氧反应、fMRI和同步EEG识别的血氧反应和头皮EEG活动之间的关系。此外，脑电模式的定量分析将用于识别可能正在启动的脑电信号的特征，并与2dTCA检测到的氧合反应相对应。拟议研究的最终成果将是：(1)一种新的、更具临床实用价值的技术，用于检测和定位随机的、瞬时的BOLD信号，将扩展分析方法用于检查癫痫发作间期(癫痫发作之间)的活动，以及其他非自愿激活模式，如抽动症中的抽搐和精神分裂症患者的幻觉；(2)更全面地了解2dTCA检测到的癫痫发作间歇活动及其与头皮脑电的关系。本研究为2dTCA和fMRI用于癫痫发作灶定位的全面临床验证奠定了基础。如果成功，对于那些负担不起与MRI兼容的EEG系统和使用这些系统所需的技术专业知识的大多数临床站点，以及那些在头皮EEG上缺乏足够活动而禁止使用同步EEG方法的患者，将能够利用fMRI的空间定位能力。

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.