Abstract:
:Calibration of the spatial sensitivity functions of coil arrays is a crucial element in parallel magnetic resonance imaging (PMRI). The most common approach has been to measure coil sensitivities directly using one or more low-resolution images acquired before or after accelerated data acquisition. However, since it is difficult to ensure that the patient and coil array will be in exactly the same positions during both calibration scans and accelerated imaging, this approach can introduce sensitivity miscalibration errors into PMRI reconstructions. This work shows that it is possible to extract sensitivity calibration images directly from a fully sampled central region of a variable-density k-space acquisition. These images have all the features of traditional PMRI sensitivity calibrations and therefore may be used for any PMRI reconstruction technique without modification. Because these calibration data are acquired simultaneously with the data to be reconstructed, errors due to sensitivity miscalibration are eliminated. In vivo implementations of self-calibrating parallel imaging using a flexible coil array are demonstrated in abdominal imaging and in real-time cardiac imaging studies.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
McKenzie CA,Yeh EN,Ohliger MA,Price MD,Sodickson DKdoi
10.1002/mrm.10087subject
Has Abstractpub_date
2002-03-01 00:00:00pages
529-38issue
3eissn
0740-3194issn
1522-2594pii
10.1002/mrm.10087journal_volume
47pub_type
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