Regional ventilation and distribution of emphysema - a quantitative comparison.
The distribution of ventilation and emphysema throughout the lung was compared in 20 emphysematous patients who were candidates for lung volume reduction surgery. Ventilation distribution among 1.6-cm-high stripe regions was obtained in supine position by planar gamma camera scintigraphy after inhalation of technegas. Results from nine healthy subjects provided normal stripe count rates. Patient count rates were expressed as the difference from predicted normal stripe count rate (DeltaSVI). Thus, DeltaSVI is a relative index of abnormal ventilation. Emphysema was assessed quantitatively by a density mask method on corresponding slices of high resolution computed tomography (HRCT). The results show that in the majority of patients, there is a highly significant relationship between the degree of stripe hypoventilation and the amount of distribution of emphysema, but in some patients no such relationship is found. We speculate that the distribution of airway obstruction not necessarily follows the distribution of emphysema, which could explain the lack of concordance between ventilation and emphysema distribution in some patients. We conclude that ventilation scintigraphy contains complementary information to lung HRCT.
Johansson
Ake
A
The Sahlgrenska Academy at Göteborg University, Sahlgrenska University Hospital, Göteborg, Sweden. ake.johansson@vgregion.se
Vikgren
Jenny
J
Moonen
Michaela
M
Tylén
Ulf
U
Bake
Björn
B
D000328:Adult; D000336:Aerosols / Q000493:pharmacokinetics; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011656:Pulmonary Emphysema / Q000000981:diagnostic imaging* / Q000378:metabolism; D012123:Pulmonary Ventilation; D011859:Radiography; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D013670:Sodium Pertechnetate Tc 99m / Q000493:pharmacokinetics; D013223:Statistics as Topic; D013382:Subtraction Technique; D014018:Tissue Distribution
D000336:Aerosols; D019275:Radiopharmaceuticals; C056708:Technegas; D013670:Sodium Pertechnetate Tc 99m