Entrenamiento olfatorio: revisión de literatura / Olfactory training: review of literature

RESUMEN La disfunción olfatoria es una patología frecuente que trae consigo una disminución importante en la calidad de vida de los pacientes y que incluso conlleva una mortalidad aumentada respecto a la población general. Sin embargo, es una condición subdiagnosticada, ya sea por desconocimiento de los profesionales o por falta de un método diagnóstico adecuado. A la fecha no existe un tratamiento efectivo para estos pacientes y generalmente se les deja sin tratar. Una alternativa para este gran problema es el entrenamiento olfatorio, tratamiento propuesto recientemente con resultados promisorios.

ABSTRACT Olfactory dysfunction is a frequent pathology associated with an important decrease in the quality of life of patients and an increased mortality respect to the general population. However, it is an underdiagnosed condition, either due to lack of knowledge of the professionals or due to the lack of an adequate diagnostic method. To date there is no effective treatment for these patients and they are usually left untreated. An alternative to this problem is olfactory training, a treatment recently proposed with promising results.

Effectiveness of olfactory rehabilitation according to a structured protocol with potential of regaining pre-operative levels in laryngectomy patients using nasal airflow-inducing manoeuvre.

This pilot study aims to evaluate the effectiveness of the Nasal Airflow-Inducing Manoeuvre (NAIM) when employing a structured protocol as well as investigate if early rehabilitation has the potential to return olfaction to pre-operative levels in patients undergoing laryngectomy following laryngeal cancer. Prospective study of cases conducted during 1 year, 2009­2010, at the Department of Ear-, Nose and Throat at Sahlgrenska University Hospital, Gothenburg, Sweden. Ten patients with laryngeal cancer and about to undergo laryngectomy were identified, of which four were included in the study. The remaining six patients were unfit to participate (n = 4) or declined participation (n = 2). Testing was conducted pre- and post-operatively and at each NAIM training session. Patients received three initial NAIM sessions followed by reinforcement training at 3, 6 and 12 months. Measures included Scandinavian Odour-Identification Test (SOIT), a semi-structured interview and questionnaires including European Organisation for Research and Treatment of Cancer, QLQ-C30 and QLQ-H&N35. All patients were normosmic smellers according to SOIT at the study end-point. One patient reported higher SOIT scores at 12 months follow-up compared to pre-operatively. Remaining patients had scores close to that reported pre-operatively. Using subjective measures, olfaction improved in all patients with one patient's final score surpassing pre-operative scores. By implementing a structured protocol consisting of three training sessions early following laryngectomy with additional reinforcement sessions at 3, 6 and 12 months, NAIM is effective in terms of improving smelling ability. There also appears to be potential for restoring olfaction to a patient's pre-operative level as reflected by both olfactory testing and PRO instruments. However, larger studies are needed to further explore the findings highlighted by this study.

[Olfactory rehabilitation after total laryngectomy]. / Rehabilitación olfativa tras la laringectomía total.

OBJECTIVES: To analyze the olfactory function in patients after total laryngectomy and evaluate the outcomes of the use of the induced nasal airflow manoeuvre. MATERIAL AND METHODS: A prospective clinical intervention study was carried out with 41 patients who had undergone total laryngectomy, of which 39 were male and 2 female. After verifying that there were no anatomical disorders, the patients were given an olfaction test that classified them into two groups, those with olfactory perception and those without. All underwent rehabilitation using the induced nasal airflow technique and, subsequently, the olfaction test was repeated to enable a comparison with the first results obtained. A semi-structured interview was held to evaluate the senses of taste and smell of the participants, also taking into account their own opinion. RESULTS: Out of the 41 patients included in the study, 9 had olfactory perception before rehabilitation, according to the first olfaction test. The use of the nasal airflow maneuver meant the recovery or improvement of the olfactory capacity in 90.24% of the patients. CONCLUSIONS: The induced nasal airflow technique enables an important recovery of olfaction and improvement of taste after total laryngectomy. This technique is easy to learn and to repeat. It does not require expensive materials. The recovery of olfaction and taste implies an improvement in quality of life for the patient, so this technique should be included in all protocols of comprehensive rehabilitation after total laryngectomy.