title: Assessment of olfactory nerve by SPECT-MRI image with nasal thallium-201 administration in patients with olfactory impairments in comparison to healthy volunteers.
abstract: OBJECTIVE
  The aim of this study was to assess whether migration of thallium-201 ((201)Tl) to the olfactory bulb were reduced in patients with olfactory impairments in comparison to healthy volunteers after nasal administration of (201)Tl.
  
  
  METHODS
  10 healthy volunteers and 21 patients enrolled in the study (19 males and 12 females; 26-71 years old). The causes of olfactory dysfunction in the patients were head trauma (n = 7), upper respiratory tract infection (n = 7), and chronic rhinosinusitis (n = 7). (201)TlCl was administered unilaterally to the olfactory cleft, and SPECT-CT was conducted 24 h later. Separate MRI images were merged with the SPECT images. (201)Tl olfactory migration was also correlated with the volume of the olfactory bulb determined from MRI images, as well as with odor recognition thresholds measured by using T&T olfactometry.
  
  
  RESULTS
  Nasal (201)Tl migration to the olfactory bulb was significantly lower in the olfactory-impaired patients than in healthy volunteers. The migration of (201)Tl to the olfactory bulb was significantly correlated with odor recognition thresholds obtained with T&T olfactometry and correlated with the volume of the olfactory bulb determined from MRI images when all subjects were included.
  
  
  CONCLUSIONS
  Assessment of the (201)Tl migration to the olfactory bulb was the new method for the evaluation of the olfactory nerve connectivity in patients with impaired olfaction.
authors.affiliation: Department of Otorhinolaryngology, Kanazawa Medical University, Ishikawa, Japan. shigah@kanazawa-med.ac.jp
authors.forename: Hideaki
authors.initials: H
authors.lastname: Shiga
authors.forename: Junichi
authors.initials: J
authors.lastname: Taki
authors.forename: Kohshin
authors.initials: K
authors.lastname: Washiyama
authors.forename: Junpei
authors.initials: J
authors.lastname: Yamamoto
authors.forename: Sakae
authors.initials: S
authors.lastname: Kinase
authors.forename: Koichi
authors.initials: K
authors.lastname: Okuda
authors.forename: Seigo
authors.initials: S
authors.lastname: Kinuya
authors.forename: Naoto
authors.initials: N
authors.lastname: Watanabe
authors.forename: Hisao
authors.initials: H
authors.lastname: Tonami
authors.forename: Kichiro
authors.initials: K
authors.lastname: Koshida
authors.forename: Ryohei
authors.initials: R
authors.lastname: Amano
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Furukawa
authors.forename: Takaki
authors.initials: T
authors.lastname: Miwa
mesh_terms: D000281:Administration, Intranasal; D000328:Adult; D000368:Aged; D001692:Biological Transport; D016022:Case-Control Studies; D006259:Craniocerebral Trauma / Q000150:complications; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D000857:Olfaction Disorders / Q000000981:diagnostic imaging* / Q000209:etiology / Q000378:metabolism* / Q000503:physiopathology; D009830:Olfactory Bulb / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D009832:Olfactory Nerve / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D012141:Respiratory Tract Infections / Q000150:complications; D012684:Sensory Thresholds; D012852:Sinusitis / Q000150:complications; D013794:Thallium Radioisotopes / Q000008:administration & dosage / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D013794:Thallium Radioisotopes