title: A new method for respiratory gating during microcomputed tomography of lung in mice.
abstract: This study investigated the use of regulated cyclic breath-holds to improve microcomputed tomography (microCT) imaging of small (diameter, less than 1 mm) mouse lung tumors in vivo. Two novel techniques that use a modified small-animal ventilator were examined and compared with a previously used respiratory gating microCT technique and a free-breathing microCT technique. Two mice were scanned with each of these 4 microCT techniques (voxel size, 92 microm). The appearance of small lung tumors (maximal diameter, 0.5 to 1.0 mm) and the characteristics of line profiles of the lung-diaphragm boundary were used to compare the images obtained from the 4 acquisition techniques. The use of cyclic breath-holds, synchronized with the CT exposures, led to marked improvement in the visualization of the mouse lung structure and lesion conspicuity. A secondary experiment was performed to assess the stress placed on mice by the acquisition techniques.
authors.affiliation: Department of IMaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA. ejohnson@di.mdacc.tmc.edu
authors.forename: Evan M
authors.initials: EM
authors.lastname: Johnson
authors.forename: Roger E
authors.initials: RE
authors.lastname: Price
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Kurie
authors.forename: Belinda S
authors.initials: BS
authors.lastname: Rivera
authors.forename: Dianna D
authors.initials: DD
authors.lastname: Cody
mesh_terms: D000818:Animals; D001831:Body Temperature; D004562:Electrocardiography / Q000662:veterinary; D005260:Female; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D051379:Mice; D008822:Mice, Transgenic; D008904:Miniaturization; D012119:Respiration; D012143:Respiratory Physiological Phenomena; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*