Mild traumatic brain injury: evaluation of olfactory dysfunction and clinical-neurological characteristics

Brain Inj. 2018;32(5):550-556. doi: 10.1080/02699052.2018.1432074. Epub 2018 Feb 15.


Objective: To evaluate olfactory function and clinical-neurological characteristics in a group of patients with mild head trauma.

Methods: A total of 352 patients with MTBI underwent olfactory function evaluation. The site of head trauma, loss of consciousness <20 min, memory loss, subjective presence or absence of olfaction and other clinical, neurological and radiological aspects were evaluated and compared with the olfactory dysfunction.

Results: A total of 33.5% patients enrolled in the study had an olfactory dysfunction. Eighty-seven percent of the patients had a diagnosis of anosmia whereas 13% had a diagnosis of hyposmia. Statistical analysis did not show a correlation between radiologically detected head lesions and different types of olfactory dysfunction (p > 0.05). Besides, no difference between head lesion site and different olfactory dysfunction was reported (p = 0.5). Regarding olfactory sub-tests a low detection threshold was present in these patients.

Conclusion: The possibility of olfactory dysfunction should be considered in any case of MTBI appears differently than expected, a minor head injury causes anosmia much more frequently than hyposmia.

Keywords: Glasgow coma scale; Head trauma; Sniffin’ Sticks; olfactory dysfunction.

MeSH terms

  • Adolescent
  • Adult
  • Brain Injuries, Traumatic / complications*
  • Brain Injuries, Traumatic / diagnostic imaging
  • Child
  • Child, Preschool
  • Consciousness Disorders / etiology
  • Female
  • Glasgow Coma Scale
  • Humans
  • Infant
  • Infant, Newborn
  • Magnetic Resonance Imaging
  • Male
  • Memory Disorders / diagnosis
  • Memory Disorders / etiology
  • Neurologic Examination
  • Olfaction Disorders / diagnosis*
  • Olfaction Disorders / etiology*
  • Retrospective Studies
  • Tomography Scanners, X-Ray Computed
  • Young Adult