Determination of respiratory phase during acquisition of airway cine MR images.
Subjects were imaged on a 1.5-T Signa MRI system using the head-neck vascular coil. An axial fast gradient echo cine, at the base of the second cervical vertebra, was obtained. A total of 128 images were acquired with a rapid image acquisition (one per second) over several respiratory cycles. The analog signal from the MR scanner (RF unblank) was utilized to determine the duration of the cine MR sequence. The phase of respiration was determined by analyzing the nasal air flow connected via pressure tubing to a pressure transducer outside the MR scanner room. We were thus able to determine the phase of respiration during acquisition of individual airway cine MR images. There was a wide range of airway volume measurements over the respiratory cycle with the lowest volume at end expiration and the highest at peak inspiration.
Kalra
Maninder
M
Division of Pulmonary Medicine, Cincinnati Children's Hospital, 3333 Burnet Avenue, Cincinnati, OH 45229, USA. maninder.kalra@cchmc.org
Donnelly
Lane F
LF
McConnell
Keith
K
O'Brien
Kendall
K
Sandhu
Jaskaran
J
Johnson
James
J
Amin
Raouf S
RS
D000293:Adolescent; D002648:Child; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008991:Monitoring, Physiologic; D012137:Respiratory System / Q000503:physiopathology*; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology*