Imaging lung function in mice using SPECT/CT and per-voxel analysis

• Published in: PloS one Vol. 7; no. 8; p. e42187
• Main Authors: Jobse, Brian N, Rhem, Rod G, McCurry, Cory A J R, Wang, Iris Q, Labiris, N Renée
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 03.08.2012; Public Library of Science (PLoS)
• Subjects: Age; Airway management; Animal models; Animals; Asthma; Biology; CAT scans; Chronic Disease; Chronic obstructive pulmonary disease; Computed tomography; Disease; Drug dosages; Emission analysis; Female; Image acquisition; Lung - diagnostic imaging; Lung - physiopathology; Lung diseases; Lung Diseases - diagnostic imaging; Lung Diseases - physiopathology; Medical imaging; Medical imaging equipment; Medical research; Medicine; Mice; Mice, Inbred BALB C; Multimodal Imaging - instrumentation; Multimodal Imaging - methods; NMR; Nuclear magnetic resonance; Nuclear medicine; Perfusion; Photon emission; Positron-Emission Tomography; Pulmonary Ventilation; Respiratory diseases; Respiratory function; Rodents; Single photon emission computed tomography; Tomography, X-Ray Computed; Ventilation; Volumetric analysis; Canada; Ontario Canada; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0042187

Chronic lung disease is a major worldwide health concern but better tools are required to understand the underlying pathologies. Ventilation/perfusion (V/Q) single photon emission computed tomography (SPECT) with per-voxel analysis allows for non-invasive measurement of regional lung function. A clinically adapted V/Q methodology was used in healthy mice to investigate V/Q relationships. Twelve week-old mice were imaged to describe normal lung function while 36 week-old mice were imaged to determine how age affects V/Q. Mice were ventilated with Technegas™ and injected with (99m)Tc-macroaggregated albumin to trace ventilation and perfusion, respectively. For both processes, SPECT and CT images were acquired, co-registered, and quantitatively analyzed. On a per-voxel basis, ventilation and perfusion were moderately correlated (R = 0.58±0.03) in 12 week old animals and a mean log(V/Q) ratio of -0.07±0.01 and standard deviation of 0.36±0.02 were found, defining the extent of V/Q matching. In contrast, 36 week old animals had significantly increased levels of V/Q mismatching throughout the periphery of the lung. Measures of V/Q were consistent across healthy animals and differences were observed with age demonstrating the capability of this technique in quantifying lung function. Per-voxel analysis and the ability to non-invasively assess lung function will aid in the investigation of chronic lung disease models and drug efficacy studies.