PURPOSE: A sliding thin slab, minimum intensity projection (STS-MinIP) is considered to be useful for detecting diseases that decrease lung attenuation. For evaluating these diseases, it would be useful to ascertain the lower limits of normal lung attenuation, allowing a division between normal and subnormal attenuation. However, normal lung attenuation may vary depending on respiratory status, anatomical position, and patient background factors. Our aim was to determine whether the lower limits of lung attenuation, without airways, in asymptomatic subjects using STS-MinIP varies under different conditions. MATERIALS AND METHODS: The study subjects were 43 volunteers without pulmonary symptoms. STS-MinIP was performed at full inspiration and full expiration at three levels of the lung. The lower limits of lung attenuation were compared among the three lung levels and between full inspiration and full expiration, the sexes, age groups, smokers and nonsmokers, and the right and left lungs. RESULTS: The lower limits of lung attenuation had significantly different Hounsfield unit values among lung levels, between the sexes at full inspiration, and between age groups at full expiration. CONCLUSION: This study shows that the lower limits of lung attenuation are influenced by lung fields, sex, and, on expiration, age.
PURPOSE: A sliding thin slab, minimum intensity projection (STS-MinIP) is considered to be useful for detecting diseases that decrease lung attenuation. For evaluating these diseases, it would be useful to ascertain the lower limits of normal lung attenuation, allowing a division between normal and subnormal attenuation. However, normal lung attenuation may vary depending on respiratory status, anatomical position, and patient background factors. Our aim was to determine whether the lower limits of lung attenuation, without airways, in asymptomatic subjects using STS-MinIP varies under different conditions. MATERIALS AND METHODS: The study subjects were 43 volunteers without pulmonary symptoms. STS-MinIP was performed at full inspiration and full expiration at three levels of the lung. The lower limits of lung attenuation were compared among the three lung levels and between full inspiration and full expiration, the sexes, age groups, smokers and nonsmokers, and the right and left lungs. RESULTS: The lower limits of lung attenuation had significantly different Hounsfield unit values among lung levels, between the sexes at full inspiration, and between age groups at full expiration. CONCLUSION: This study shows that the lower limits of lung attenuation are influenced by lung fields, sex, and, on expiration, age.
Authors: P J Mergo; W F Williams; R Gonzalez-Rothi; R Gibson; P R Ros; E V Staab; T Helmberger Journal: AJR Am J Roentgenol Date: 1998-05 Impact factor: 3.959
Authors: R K Rienmüller; J Behr; W A Kalender; M Schätzl; I Altmann; M Merin; T Beinert Journal: J Comput Assist Tomogr Date: 1991 Sep-Oct Impact factor: 1.826