A study on olfaction of the laryngectomized patients by the artificial airway tube method (author's transl)

Abstract

The authors noticed the recovery of the nasal air current in the laryngectomized patients by connecting a tube between the tracheal stoma and the naris, so named this technique an artificial airway tube method. In this manner, the olfactory acuities of 60 laryngectomized patients, ranged from 9 days to 18 5/6 years postoperatively, were evaluated by measuring the detection threshold for the smell of various odors such as beta-phenyl ethyl alcohol, cyclotene and iso-valeric acid. At the same time we also measured respectively the onset and duration time for the sense of smell of Alinamin (Thiamine propyl disulfide) administered intravenously. Aside from the methods above mentioned, it is also known that swallowing of air leads a little olfactory sensation by nasal rout in some laryngectomized individuals. Thus utilizing airswallowing, olfactory testings by these 3 odors were undergone to guess their olfaction in daily life. Results obtained are summarized as follows; 1. The mean detection threshold for each of these 3 substances in the laryngectomized patients was nearly equal to that obtained in normal persons. While in the intravenous olfaction tests, more inferior data were seen in the laryngectomized patients than that of normal controls. Namely, not only the time needed for the onset of the sense of smell was twice longer, but also its duration shortened obviously as compared with their normal values.2. The best score was revealed in the subjects within one year after surgery in comparison with the others. 3. No significant differences of the olfactory acuities were observed between the groups, one with esophageal speech and the other with artificial voice apparatus. 4. When the laryngectomized patients put on the artificial airway tube, microclimate in the nasal cavity might be similar to that of normal one. 5. Olfactory sensation by swallowing procedure appeared in 40% of the laryngectomized patients in this series. But, the mean detection thresholds of individual odors were greatly higher than those obtained by the artificial airway tube method. For olfactory sensation, the longer the postoperative period, the more increased the incidence of its appearance.This study showed that the olfaction did not change in these patients. The assumption istherefore made that neurological changes in the terminal endings in this special sense organ do not occur after total laryngectomy.