Weiying Dai1, Ajit Shankaranarayanan2, Gottfried Schlaug3, David C. Alsop1
1Radiology, Beth Israel Deaconess Medical Center & Harvard Medical School, Boston, MA, United States; 2Global Applied Science Laboratory, GE Healthcare, Menlo Park, CA, United States; 3Neurology, Beth Israel Deaconess Medical Center & Harvard Medical School, Boston, MA, United States
We report quantitative measurement of signal fluctuation from resting state networks in volumetric arterial spin labeling (ASL) perfusion images of normal volunteers. Network fluctuations are much larger than residual noise. The combined signal fluctuation from all the networks is approximately 10% of the mean perfusion signal, but the signal fluctuation amplitude varies between the different networks. Unlike the residual noise, the resting state network fluctuations cannot be reduced by greater smoothing. Resting network quantification with ASL may be useful to further study the physiology of the fluctuations and may enable improved noise reduction and statistical analysis of ASL studies.