title: Detection of olfactory dysfunction using olfactory event related potentials in young patients with multiple sclerosis.
abstract: BACKGROUND
  Several studies reported olfactory dysfunction in patients with multiple sclerosis. The estimate of the incidence of olfactory deficits in multiple sclerosis is uncertain; this may arise from different testing methods that may be influenced by patients' response bias and clinical, demographic and cognitive features.
  
  
  OBJECTIVE
  To evaluate objectively the olfactory function using Olfactory Event Related Potentials.
  
  
  METHODS
  We tested the olfactory function of 30 patients with relapsing remitting multiple sclerosis (mean age of 36.03±6.96 years) and of 30 age, sex and smoking-habit matched healthy controls by using olfactory potentials. A selective and controlled stimulation of the olfactory system to elicit the olfactory event related potentials was achieved by a computer-controlled olfactometer linked directly with electroencephalograph. Relationships between olfactory potential results and patients' clinical characteristics, such as gender, disability status score, disease-modifying therapy, and disease duration, were evaluated.
  
  
  RESULTS
  Seven of 30 patients did not show olfactory event related potentials. Sixteen of remaining 23 patients had a mean value of amplitude significantly lower than control group (p<0.01). The presence/absence of olfactory event related potentials was associated with dichotomous expanded disability status scale (p = 0.0433), as well as inversely correlated with the disease duration (r = -0.3641, p = 0.0479).
  
  
  CONCLUSIONS
  Unbiased olfactory dysfunction of different severity found in multiple sclerosis patients suggests an organic impairment which could be related to neuroinflammatory and/or neurodegenerative processes of olfactory networks, supporting the recent findings on neurophysiopathology of disease.
authors.affiliation: IRCCS Centro Neurolesi "Bonino-Pulejo", Messina, Italy.
authors.forename: Fabrizia
authors.initials: F
authors.lastname: Caminiti
authors.affiliation: IRCCS Centro Neurolesi "Bonino-Pulejo", Messina, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: De Salvo
authors.affiliation: IRCCS Centro Neurolesi "Bonino-Pulejo", Messina, Italy.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: De Cola
authors.affiliation: IRCCS Centro Neurolesi "Bonino-Pulejo", Messina, Italy.
authors.forename: Margherita
authors.initials: M
authors.lastname: Russo
authors.affiliation: IRCCS Centro Neurolesi "Bonino-Pulejo", Messina, Italy.
authors.forename: Placido
authors.initials: P
authors.lastname: Bramanti
authors.affiliation: IRCCS Centro Neurolesi "Bonino-Pulejo", Messina, Italy; Department of Biomedical Sciences and Morphological and Functional Imaging, University of Messina, Messina, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Marino
authors.affiliation: IRCCS Centro Neurolesi "Bonino-Pulejo", Messina, Italy.
authors.forename: Rosella
authors.initials: R
authors.lastname: Ciurleo
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000503:physiopathology*; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000150:complications / Q000503:physiopathology*; D000857:Olfaction Disorders / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D012903:Smell / Q000502:physiology