Rehabilitation of the Olfactory Sense after Laryngectomy: Long-term Use of the Larynx Bypass

Abstract

Patients who undergo laryngectomy typically lose their sense of smell. One device that has been used to rehabilitate olfactory function in these patients is the larynx bypass. We conducted a long-term study of the larynx bypass in 16 laryngectomized patients. After undergoing objective and subjective baseline evaluations, patients were asked to use the device at home for at least 30 minutes each day for 3 months. They were also asked to record in a diary subjective ratings of their sense of smell and the practicability of using the device every day. At study's end, patients experienced a statistically significant improvement (p < 0.001) in olfactory function on objective measurement (Sniffin’ Sticks testing). Subjective improvement was seen after 1 week (p < 0.001) and maintained throughout the study. Practicability scores improved statistically (p = 0.003), but the device remained difficult to use. The long-term use of the larynx bypass has not been studied previously, and we hope that our findings will serve as a basis for further investigation.

Evaluation of the efficacy of the ‘nasal airflow‐inducing manoeuvre’ for smell rehabilitation in laryngectomees by means of the Sniffin′ Sticks test

“…Here, 72% were anosmic, 28% were hyposmic and none of the 25 subjects reached normosmic results 22 . Goktas used only the 16‐item identification test; here, only 3 of 16 items were correctly identified on average 11 …”

“…The appearance of olfactory dysfunction after laryngectomy is well documented in different studies: 11,12,14,22 the percentage of impaired olfaction range from 58% to 75%. Most of these studies were carried out with not widely used testing methods evaluating only a threshold 12 or an identification score with limited items, 14 making a distinct classification for olfactory performance difficult.…”

“…Whereas many causes for olfactory dysfunction have little treatment options, in the case of laryngectomy, there have been techniques developed to successfully restore the nasal airflow and thus the sense of smell. The laryngeal bypass, which uses a tube between the tracheostoma and the patient’s mouth to be able to breathe through the nose again, showed a reliable improvement in the sense of smell 11 . But the intricate handling makes this device not suitable for everyday life.…”

Olfaction following total laryngectomy

“…Larynx bypass [14,[52][53][54] Rhinomanometry To objectively measure nasal airflow, pressure, and resistance in the nostrils One nostril is closed with a pressure-measuring probe whilst the other nostril remains patent and is used for rhinomanometric measuring. In TL patients, the stoma must be closed using the hand.…”

The scent-diffusing ventilator for rehabilitation of olfactory function after laryngectomy

“…1,2 However, both the one-time and the long-term use of the LB is difficult. When using the LB, it is only possible to circulate air in the nose if the patient actively cooperates.…”