Combining task-evoked and spontaneous activity to improve pre-operative brain mapping with fMRI.

Author: Fox MD1, Qian T2, Madsen JR3, Wang D4, Li M4, Ge M5, Zuo HC6, Groppe DM7, Mehta AD8, Hong B9, Liu H10.
Affiliation: 1Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. 2Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China. 3Department of Neurosurgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA. 4Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. 5Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability, Department of Biomedical Engineering, Hebei University of Technology, Tianjin, China. 6Second Affiliated Hospital of Tsinghua University, Beijing, China. 7Department of Neurosurgery, Hofstra North Shore LIJ School of Medicine, 300 Community Dr., Manhasset, NY 11030, USA; Feinstein Institute for Medical Research, 350 Community Dr., Manhasset, NY 11030, USA; Department of Psychology, University of Toronto, 100 St. George St., Toronto, ON M5S 3G3, Canada. 8Department of Neurosurgery, Hofstra North Shore LIJ School of Medicine, 300 Community Dr., Manhasset, NY 11030, USA; Feinstein Institute for Medical Research, 350 Community Dr., Manhasset, NY 11030, USA. 9Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China. Electronic address: Hongbo@tsinghua.edu.cn. 10Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. Electronic address: Hesheng@nmr.mgh.harvard.edu.
Conference/Journal: Neuroimage.
Date published: 2015 Sep 25
Other: Pages: S1053-8119(15)00845-9 , Special Notes: doi: 10.1016/j.neuroimage.2015.09.030 , Word Count: 237



Noninvasive localization of brain function is used to understand and treat neurological disease, exemplified by pre-operative fMRI mapping prior to neurosurgical intervention. The principal approach for generating these maps relies on brain responses evoked by a task and, despite known limitations, has dominated clinical practice for over 20years. Recently, pre-operative fMRI mapping based on correlations in spontaneous brain activity has been demonstrated, however this approach has its own limitations and has not seen widespread clinical use. Here we show that spontaneous and task-based mapping can be performed together using the same pre-operative fMRI data, provide complimentary information relevant for functional localization, and can be combined to improve identification of eloquent motor cortex. Accuracy, sensitivity, and specificity of our approach are quantified through comparison with electrical cortical stimulation mapping in eight patients with intractable epilepsy. Broad applicability and reproducibility of our approach are demonstrated through prospective replication in an independent dataset of six patients from a different center. In both cohorts and every individual patient, we see a significant improvement in signal to noise and mapping accuracy independent of threshold, quantified using receiver operating characteristic curves. Collectively, our results suggest that modifying the processing of fMRI data to incorporate both task-based and spontaneous activity significantly improves functional localization in pre-operative patients. Because this method requires no additional scan time or modification to conventional pre-operative data acquisition protocols it could have widespread utility.
Copyright © 2015. Published by Elsevier Inc.
PMID: 26408860