The JOEP Study: Justification of Olfactory Evaluation in Posttraumatic brain injury.

Abstract

ABSTRACT INTRODUCTION: ENT-related findings are often observed in patients with skull base fractures, a sign of traumatic brain injury. However, olfactory evaluation is often overlooked, despite proven correlation between olfactory dysfunction and traumatic brain injury. Prevalence of olfactory dysfunction in post-traumatic brain injury population varies between 12.8 and 67%, compared to 5-15% in general population. METHOD: We conducted a retrospective case series study in a single Dutch tertiary referral center. Medical records of patients diagnosed with skull base fracture were reviewed. Data was collected and analysed through Chi-squared analysis regarding patient demographics, trauma characteristics and radiographic findings, olfactory function and other ENT-related outcomes. RESULTS: Of 44 included patients aged between 18 and 75, 50% was female. 19 patients(43.2%) experienced subjective olfactory dysfunction. Olfactory outcome in 4 patients(9.1%) was missing. 30 patients(68.2%) experienced subjective hearing loss at admission, persisting in 18 patients(40.9%) at end of follow up. Vertigo and tinnitus symptoms were present in respectively 10 patients(22.7%) and 18 patients(40.9%). In 6 cases, ossicle luxation was seen. No significant distribution of outcomes on severity of trauma or olfactory function was found. CONCLUSION: Given that subjective olfactory dysfunction has been experienced in 43% of patients and that olfactory dysfunction is associated with social insecurity and hazardous events, it is essential to evaluate olfactory function in post-traumatic brain injury population. RECOMMENDATION: During hospital admission, olfactory loss should be actively assessed, with an objective olfactory test conducted after six weeks. Furthermore, prospective longitudinal studies are needed to fully investigate prevalence, treatment and recovery of olfactory dysfunction after TBI