Difficulties of olfactometric evaluation in patients accusing smell disorders after head trauma

Head trauma is considered to be the third cause of olfactory function disorders. Olfactometric assessment in patients accusing anosmia following head injury produced by car accident or aggression is important, because most of them are involved in law trials in order to obtain financial compensations from the author. It is compulsory to use both subjective and objective olfactory evaluation methods combined with a detailed anamnesis, a complete ENT examination and a good cranio-facial imaging (computed tomography or MRI) in order to exclude malingerers and to obtain an accurate diagnosis.

“Sfanta Maria” ENT Department from Bucharest is the only center in Romania where the olfactory function in completely investigated. We use chemosensory (Snap and Sniff Test and n-Butanol Dynamic Olfactometry) and electrophysiological tests (electric olfactory evoked potentials of the olfactory bulb).

Unfortunately, we confront with a series of difficulties in what concerns the smell function evaluation: 1) there is scarce information in the literature regarding the olfactory electric evoked potentials; 2) the electric olfactory evoked potentials register only the electrical activity in the olfactory bulb; 3) in case of olfactory impairment medically confirmed, we cannot establish a cause-effect relationship between the disturbance and the event; 4) the most accurate electrophysiological assessment method currently available in Europe is the time-frequency analysis of chemosensory event-related potentials, but we do not dispose of the necessary equipment yet; 5) sometimes patients do not give us the informed consent for a complete olfactory evaluation.