As one of the therapies for otorhinolaryngological diseases, aerosol therapy for diseases of the larynx as well as those of the nose and paranasal sinuses is frequently prescribed. In a statistical evaluation of aerosol therapy during a survey of medical practitioners in Osaka and Nara prefectures, the reported incidence was high and the rate ranged about 30%. Many researchers reported effects from aerosol therapy for diseases of the nose and paranasal sinuses, but there were few reports of laryngeal aerosol therapy. In this symposium, we will initially study the actual use of laryngeal aerosol therapy. The first speaker will be Dr. Kouno. He will show the statistical incidence and manner in which doctors are using laryngeal aerosol therapy. Next, four researchers will describe and clinical studies regarding laryngeal aerosol therapy. Dr. Wakuda will describe the accumulation of the aerosol particles in the respiratory tract according to differences in types of equipment and differences in the way of inhalation. Dr. Nonaka will describe basic problems in the accumulation of the aerosol particles in the respiratory tract according to differences in humidity, temperature and acceleration of particles. Dr. Hyo will describe effective aerosol therapy for all sorts of diseases of the larynx and the confirmation of the experimental and clinical efficacy due to the addition of the pressure during inhalation. Dr. Iwata will describe some clinical problems such as the difference between the oral and nasal methods and the effects of aerosol therapy for allergic diseases involving the larynx. We hope to develop additional subjects after obtaining such useful information about laryngeal aerosol therapy.
Studies in aerosol therapy for the larynx have suggested that at vocalization, much amount of aerosol drug is able to be deposited because path of vocal cords becomes narrow. The mechanism for this particle deposition was investigated using both a model cast and a living organ of human larynx to check partial deposition efficiency for each part of larynx. Total aerosol deposition was found to be characterized by higher efficiency of particle impaction and circulated air flow formed as the narrow path of the vocal cords. The effectiveness of SPSU-12 nebulizer with a mouth adapter was examined in relation to the clinical testings for acute and chronic laryngitis by means of evaluating the disease types and the drug availability of pathogen.