THURSDAY, June 19 (HealthDay News) -- The olfactory bulb in the
brain -- the brain's "smell center" -- may change in size as a
person's sense of smell changes, a German study reports.
In this study, researchers at the University of Dresden Medical
School studied 20 people with loss of sense of smell. At the start
of the study, the patients underwent an assessment that included
MRI of the brain and nasal endoscopy, an examination of the inside
of the nose using a flexible instrument called an endoscope. Their
ability to detect odors, discriminate between odors and identify
particular odors was also tested. The full assessment was repeated
13 to 19 months later.
At the first assessment, seven of the 20 patients had no sense
of smell (anosmia) and 13 had a reduced sense of smell (hyposmia).
At the second assessment, six had anosmia and 14 had hyposmia, the
study found.
In patients who initially had hyposmia, the volume of the
olfactory bulb increased as the patients' sense of smell increased.
But there was no correlation between the volume of the olfactory
bulb and the ability to distinguish between or identify specific
odors.
The study was published in the June issue of the journal
Archives of Otolaryngology -- Head & Neck Surgery.
"The correlation between olfactory bulb volume and olfactory
function may potentially be used in combination with other factors
influencing olfaction such as remaining olfactory function, age and
duration of olfactory loss as a means to provide patients with
individual information on the prognosis of their disease," the
study authors wrote.
"Hypothetically, a multifactorial approach could be applied to
eventually come up with a formula that would allow a more precise
prognosis of olfactory function. Especially since therapeutic
options in patients with olfactory loss are limited, at present,
this type of information is of high clinical significance."
More information
The U.S. National Institute on Deafness and Other Communication
Disorders has more about
smell disorders.
