[Olfactory bulb volume in patients with posttraumatic olfactory dysfunction].

Objective: To analyze the correlation between olfactory bulb(OB) volume and olfactory function in patients with posttraumatic olfactory dysfunction. Methods: Forty patients with posttraumatic olfactory dysfunction were compared with forty controls in terms of olfactory function T&T testing, OB volume assessed with magnetic resonance imaging (MRI). SPSS 17.0 software was used to analyze the data. Results: T&T olfactory testing revealed that patients with posttraumatic olfactory dysfunction had higher scores than controls(3.47±0.63 vs.1.39±0.19, t=4.317, P<0.05). Both men and women with posttraumatic olfactory dysfunction were affected by the same extent of olfactory loss(3.52±0.66 vs.3.43±0.61, t=0.896, P>0.05). Both men and women as controls were affected by the same extent of olfactory loss(1.41±0.20 vs.1.38±0.17, t=1.073, P>0.05). OB volume of left side in patients with posttraumatic olfactory dysfunction were (36.15±3.16)mm(3,) right side were (39.28±3.76)mm(3,) average OB volume were (37.55±3.42)mm(3;) OB volume of left side in controls were (81.74±5.87)mm(3,) right side were (83.58±6.13)mm(3,) average OB volume were (82.59±5.99)mm(3;) OB volumes were lower in patients with posttraumatic olfactory dysfunction as compared with controls(t value were 4.815, 4.837 and 4.825, all P<0.01). Average olfactory discriminate threshold was negatively correlated with average OB volume in posttraumatic olfactory dysfunction and controls(r value was-0.582, -0.564, both P<0.05). Average olfactory discriminate threshold was positively correlated with impairment degree in patients with posttraumatic olfactory dysfunction(r value was 0.472, P<0.05), average OB volume was negatively correlated with impairment degree in patients with posttraumatic olfactory dysfunction(r value was -0.397, P<0.05) Conclusions: The OB volumes are lower in patients with posttraumatic olfactory dysfunction as compared with controls. The OB volume is correlated with olfactory function. Impairment degree in patients with posttraumatic olfactory dysfunction is accordance with olfactory function lowering degree. Megnetic resonance imaging can be used as a supplementary diagnostic tool for patients with posttraumatic olfactory dysfunction.