Significance of intravenous olfaction test using thiamine propyldisulfide (Alinamin) in olfactometry

The significance of intravenous olfaction test in olfactometry was studied by injection of thiamine propyldisulfide (Alinamin) intravenously. An original solution of Alinamin is a thiol-type derivative of vitamin B1, and releases a mercaptan smell (garlic smell) in expired air when it arrives at the olfactory epithelium via the nasopharynx. In the intravenous olfaction test (Alinamin test), the latent time which is a period between the initiation of injection and recognition of garlic smell, and duration time which is a period between the recognition and disappearance of smell are measured. Our results indicated that latent time is influenced by olfactory acuity and duration time depends on olfactory adaptation phenomenon. Central olfactory disorders were highly suspected in hyposmia patients with duration time of less than 15 sec, and nonresponders in Alinamin test always showed poor prognosis in the recovery of olfactory acuity. It was considered that the Alinamin test is useful not only for estimating the degree of olfactory disorders, but also for differential diagnosis of impaired lesions and olfactory prognosis.