Title
Transfer function analysis of respiratory and cardiac pulsations in human brain observed on dynamic magnetic resonance images.
Abstract
Magnetic resonance (MR) imaging provides a noninvasive, in vivo imaging technique for studying respiratory and cardiac pulsations in human brains, because these pulsations can be recorded as flow-related enhancement on dynamic MR images. By applying independent component analysis to dynamic MR images, respiratory and cardiac pulsations were observed. Using the signal-time curves of these pulsations as reference functions, the magnitude and phase of the transfer function were calculated on a pixel-by-pixel basis. The calculated magnitude and phase represented the amplitude change and temporal delay at each pixel as compared with the reference functions. In the transfer function analysis, near constant phases were found at the respiratory and cardiac frequency bands, indicating the existence of phase delay relative to the reference functions. In analyzing the dynamic MR images using the transfer function analysis, we found the following: (1) a good delineation of temporal delay of these pulsations can be achieved; (2) respiratory pulsation exists in the ventricular and cortical cerebrospinal fluid; (3) cardiac pulsation exists in the ventricular cerebrospinal fluid and intracranial vessels; and (4) a 180-degree phase delay or inverted amplitude is observed on phase images.
Year
DOI
Venue
2013
10.1155/2013/157040
COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE
Keywords
Field
DocType
pulsatile flow,respiratory mechanics,computational biology
Pulsatile flow,Computer science,Group delay and phase delay,Transfer function,Independent component analysis,Nuclear magnetic resonance,Amplitude,Respiratory physiology,Preclinical imaging,Magnetic resonance imaging
Journal
Volume
ISSN
Citations 
2013
1748-670X
0
PageRank 
References 
Authors
0.34
3
7
Name
Order
Citations
PageRank
Yi-hsuan Kao152.49
Wan-Yuo Guo2194.66
Adrain Jy-Kang Liou300.34
Ting-Yi Chen440.77
Chau-Chiun Huang500.34
Chih-Che Chou6527.61
Jiing-Feng Lirng7152.13