Ventilation and drug delivery to the paranasal sinuses: studies in a nasal cast using pulsating airflow.
BACKGROUND
Although there is a high incidence of nasal disorders including chronic sinusitis, there is limited success in the topical drug delivery to the nose and the paranasal sinuses. This is caused by the nose being an efficient filter for inhaled aerosol particles and the paranasal sinuses being virtually non ventilated


METHODS
The objective of this study was to visualize the efficiency of sinus ventilation in a nasal cast using dynamic 81mKr-gas imaging in combination with pulsating airflows. Furthermore, the efficiency of the deposition of radiolabelled aerosol was assessed.


RESULTS
Pulsation increased ventilation efficiency of the sinuses more than fivefold and aerosol deposition efficiency more than twentyfold, compared to delivery without pulsation. Furthermore pulsation increased aerosol deposition in the nasal airways by a factor of three. Using pulsating airflow Kr-gas ventilation and aerosol deposition efficiencies increased with increasing sinus volume. Pulsating airflow resulted in a deposition of up to 8% of the nebulized drug within the sinuses compared to 0.2% without pulsation.


CONCLUSIONS
The study demonstrates the high efficiency of a pulsating airflow in paranasal sinus ventilation and aerosolized drug delivery. This proves that topical drug delivery to the paranasal sinuses in relevant quantities is possible.
Clinical Cooperation Group, Inflammatory Lung Diseases', Helmholtz Center Munich--German Research Center for Environmental Health, Gauting, Germany moeller@helmholtz-muenchen.de
Winfried
W
Möller
Uwe
U
Schuschnig
Gabriele
G
Meyer
Heribert
H
Mentzel
Manfred
M
Keller
D000281:Administration, Intranasal; D000336:Aerosols / Q000008:administration & dosage* / Q000493:pharmacokinetics; D016503:Drug Delivery Systems; D015902:Gamma Cameras; D005740:Gases; D006801:Humans; D007726:Krypton; D010256:Paranasal Sinuses / Q000000981:diagnostic imaging / Q000378:metabolism*; D012123:Pulmonary Ventilation / Q000502:physiology; D011673:Pulsatile Flow; D011877:Radionuclide Imaging; D012852:Sinusitis / Q000188:drug therapy
D000336:Aerosols; D005740:Gases; D007726:Krypton