Can we smell without an olfactory bulb?
BACKGROUND
Lack of an olfactory bulb (OB) is typically associated with anosmia.


METHODS
We present a patient with subnormal olfactory function in whom the OB could not be detected with magnetic resonance imaging (MRI).


RESULTS
Olfactory function was evaluated on two occasions. Orthonasal olfactory function was assessed with the "Sniffin' Sticks" test providing a score equivalent to hyposmia. Retronasal olfactory function was studied with "smell powders" indicating a decreased, but not absence of, olfactory function. Importantly, chemosensory event-related potentials were clearly present in response to olfactory and trigeminal stimuli.


CONCLUSIONS
This indicates that olfactory function may be present in some subjects even when an OB can not be detected with MRI.
Rombaux
Philippe
P
Department of Otorhinolaryngology, Cliniques Universitaires Saint Luc, Brussels, Belgium. philippe.rombaux@orlo.ucl.ac.be
Mouraux
André
A
Bertrand
Bernard
B
Duprez
Thierry
T
Hummel
Thomas
T
D000328:Adult; D001921:Brain / Q000473:pathology; D005071:Evoked Potentials; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D009812:Odorants; D000857:Olfaction Disorders / Q000503:physiopathology*; D009830:Olfactory Bulb / Q000033:anatomy & histology / Q000473:pathology / Q000502:physiology*; D009833:Olfactory Pathways; D012684:Sensory Thresholds; D012903:Smell / Q000502:physiology*; D013268:Stimulation, Chemical; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods