Abstract: Background: Many types of sinus
illness produce olfactory impairment. The initial relay for sensory information
to the central nervous system is the olfactory bulb, which may be malleable and
impacted by deprivation. Olfactory dysfunction may be assessed objectively
using magnetic resonance imaging. To compare the olfactory bulb capacity in
chronic nasal obstruction owing to septal deviation and CRSwNP patients by
side, duration, severity, and subjective sensation of smell.
Method: A cross-sectional
research of 43 patients at Al-Yarmouk Teaching Hospital was divided into three
groups: (A) control, (B) septal deviation, and (C) CRSwNP. All groups were
referred for olfactory bulb magnetic resonance imaging. Using T2-weighted 3D
sequence, bulb volume, nasal obstruction in the two diseases, subjective scent,
and other characteristics were compared across groups.
Results: Patients aged ≥ 40
years, those with polyposis (20.28 mm3), those with septal deviation
(25.82 mm3), and those with subjective anosmia/hyposmia had
significantly lower mean olfactory bulb volume compared to controls (23.47 VS
44.92.0 mm3, P= 0.001). Both illness groups showed no significant
volume difference in blockage duration > 5 years. Significant weak negative
relationships were found between obstruction duration, NOSE score, and volume.
Conclusion: Nasal obstruction
reduces olfactory bulb capacity and is impacted by severity, length, pathology,
and subjective anosmia/hyposmia. Polyposis causes higher volume decrease than
septal deviation, which reduces more on the deviation side. After 5 years,
olfactory bulb volume decreases approximately equally independent of blockage
degree and disease.