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Risk of decline and chance of improvement in olfaction among patients with post-traumatic olfactory loss

Published online by Cambridge University Press:  22 October 2015

C-L Kuo
Department of Otolaryngology – Head and Neck Surgery, Taipei Veterans General Hospital, Taipei, Taiwan, Republic of China Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan, Republic of China Department of Otolaryngology, National Yang-Ming University School of Medicine, Taipei, Taiwan, Republic of China Department of Otolaryngology, Taoyuan Armed Forces General Hospital, Taiwan, Republic of China Department of Otolaryngology, Hsinchu Armed Force Hospital, Taiwan, Republic of China
C-H Shu*
Department of Otolaryngology – Head and Neck Surgery, Taipei Veterans General Hospital, Taipei, Taiwan, Republic of China Department of Otolaryngology, National Yang-Ming University School of Medicine, Taipei, Taiwan, Republic of China
Address for correspondence: Dr Chih-Hung Shu, Department of Otorhinolaryngology – Head and Neck Surgery, Taipei Veterans General Hospital, No. 201, Section 2, Shih-Pai Road, Taipei 112, Taiwan, Republic of China Fax: +886 2 2875 5715 E-mail:



To evaluate the chance of improvement and risk of decline in olfaction among patients with post-traumatic olfactory loss.


This study comprised 80 patients. Changes in olfaction were determined using a visual analogue scale and the ‘Sniffin’ Sticks' test. Logistic regression was used to identify predictors for olfactory changes.


Olfactory changes were observed in 9–35 per cent of patients. The rates of improvement and decline according to visual analogue scale scores were 35 per cent and 10 per cent respectively, whereas those in the Sniffin’ Sticks test were 9 per cent and 11 per cent respectively. There was a predictive link between non-anosmia and decline in Sniffin’ Sticks test scores (odds ratio = 16.61, p = 0.003). A positive correlation was observed between the scores in the first and last examinations (rho = 0.532, p < 0.001).


Patients should be informed that they may experience an improvement or decline in olfaction following post-traumatic olfactory dysfunction. This study provides evidence to support comprehensive counselling regarding prognosis as an integral part of management strategies.

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Copyright © JLO (1984) Limited 2015 

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Presented orally at the 118th American Academy of Otolaryngology – Head and Neck Surgery Annual Meeting and OTO EXPOSM, 21–24 September 2014, Orlando, Florida, USA.


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