PURPOSE: To demonstrate that high-resolution computed tomography (CT) can be used to quantify loss of pulmonary compliance in irradiated mice. METHODS AND MATERIALS: Computed tomography images of three nonirradiated (controls) and three irradiated mice were obtained 200 days after a single dose of 16-Gy Co (60) thoracic irradiation. While intubated, each animal was imaged at static breath-hold pressures of 2, 10, and 18 cm H2O. A deformable image registration algorithm was used to calculate changes in air volume between adjacent-pressure CT image pairs (e.g., 2 and 10 cm H2O), and functional images of pulmonary compliance were generated. The mass-specific compliance was calculated as the change in volume divided by the pressure difference between the 2 image sets and the mass of lung tissue. RESULTS: For the irradiated mice, the lung parenchyma mean CT values ranged from -314 (+/- 11) Hounsfield units (HU) to -378 (+/- 11) HU. For the control mice, the mean CT values ranged from -549 (+/- 11) HU to -633 (+/- 11) HU. Irradiated mice had a 60% (45, 74%; 95% confidence interval) lower mass-specific compliance than did the controls (0.039 [+/- 0.0038] vs. 0.106 [+/- 0.0038] mL air per cm H2O per g lung) from the 2-cm to 10-cm H2O CT image pair. The difference in compliance between groups was less pronounced at the higher distending pressures. CONCLUSION: High-resolution CT was used to quantify a reduction in mass-specific compliance following whole lung irradiation in mice. This small animal radiation injury model and assay may be useful in the study of lung injury.
PURPOSE: To demonstrate that high-resolution computed tomography (CT) can be used to quantify loss of pulmonary compliance in irradiated mice. METHODS AND MATERIALS: Computed tomography images of three nonirradiated (controls) and three irradiated mice were obtained 200 days after a single dose of 16-Gy Co (60) thoracic irradiation. While intubated, each animal was imaged at static breath-hold pressures of 2, 10, and 18 cm H2O. A deformable image registration algorithm was used to calculate changes in air volume between adjacent-pressure CT image pairs (e.g., 2 and 10 cm H2O), and functional images of pulmonary compliance were generated. The mass-specific compliance was calculated as the change in volume divided by the pressure difference between the 2 image sets and the mass of lung tissue. RESULTS: For the irradiated mice, the lung parenchyma mean CT values ranged from -314 (+/- 11) Hounsfield units (HU) to -378 (+/- 11) HU. For the control mice, the mean CT values ranged from -549 (+/- 11) HU to -633 (+/- 11) HU. Irradiated mice had a 60% (45, 74%; 95% confidence interval) lower mass-specific compliance than did the controls (0.039 [+/- 0.0038] vs. 0.106 [+/- 0.0038] mL air per cm H2O per g lung) from the 2-cm to 10-cm H2O CT image pair. The difference in compliance between groups was less pronounced at the higher distending pressures. CONCLUSION: High-resolution CT was used to quantify a reduction in mass-specific compliance following whole lung irradiation in mice. This small animal radiation injury model and assay may be useful in the study of lung injury.
Authors: Markus Velten; Rodney D Britt; Kathryn M Heyob; Stephen E Welty; Britta Eiberger; Trent E Tipple; Lynette K Rogers Journal: Am J Physiol Regul Integr Comp Physiol Date: 2012-06-20 Impact factor: 3.619
Authors: Xiaodong Zhang; Kuai-le Zhao; Thomas M Guerrero; Sean E McGuire; Brian Yaremko; Ritsuko Komaki; James D Cox; Zhouguang Hui; Yupeng Li; Wayne D Newhauser; Radhe Mohan; Zhongxing Liao Journal: Int J Radiat Oncol Biol Phys Date: 2008-09-01 Impact factor: 7.038