Regional deposition of inhaled hygroscopic aerosols: in vivo spect
compared with mathematical deposition modeling.
Finlay, W. H., K. W. Stapleton, H. K. Chan, P. Zuberbuhler, I. Gonda.
Dept. of Mechanical Engineering, University of Alberta, Edmonton,
Alberta, Canada, T6G 2G8, Department of Pharmacy, University of
Sydney, Sydney, NSW 2006, Australia, Cystic Fibrosis and Pediatric
Clinic, Univ. of Alberta Hospital, Edmonton, Alberta, Canada T6G 2G3,
Aradigm Corporation, 26219 Eden Landing Road, Hayward, CA 94545
APStracts 3:0132A, 1996.
The regional deposition patterns of inhaled hygroscopic aerosols
obtained in vivo in the studies of Phipps et al. (Am. Rev. Respir.
Dis. 139:1516, 1989 and Eur. Resp. J. 7:1474, 1994) and Chan et al.
(Eur. Resp. J. 7:1483, 1994) using single photon emission
computerized tomography (SPECT) are compared to the regional
deposition predicted by the hygroscopic lung deposition model of
Finlay & Stapleton (J. Aerosol Sci. 26:655, 1995). Three pairs of
saline aerosols are considered: isotonic with small (2.6 [mu]m MMAD,
GSD 1.4) vs. large (5.5 [mu]m MMAD, GSD 1.7) droplets; hypotonic
(0.3% NaCl) vs. hypertonic (4.5% NaCl) with 3.7-3.8 [mu]m MMAD (GSD
1.4), and hypotonic vs. hypertonic (3.7-3.8 [mu]m MMAD, GSD 1.5-1.8)
with reduced number of droplets per cm3. For each of the three pairs
of aerosols, no significant difference (p>0.05) is found between
the in vivo and computational results for either the mean value or
the variance of the difference, d, in peripheral to central
deposition. Thus, it appears that theoretical calculations can be
used to predict the pattern of lung deposition of hygroscopic
aerosols in populations of normal subjects.
Received 7 December 1995; accepted in final form 7 February 1996.
APS Manuscript Number A1266-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 20 March 96