Evaluation of chemosensory function in patients with upper respiratory tract post-viral olfactory dysfunction / 中华耳鼻咽喉头颈外科杂志

Objective: To observe the changes of olfactory function, intranasal trigeminal nerve function and taste function in patients with upper respiratory tract post-viral olfactory dysfunction (PVOD), and to explore the correlation of chemosensory function. Methods: The clinical data of 42 patients with PVOD who visited to the Olfactory and Taste Center of Otorhinolaryngology Head and Neck Surgery Department of Beijing Anzhen Hospital from January to December of 2019 were analyzed retrospectively, including 20 males and 22 females, aging (48.86±11.47) years (x¯). Twenty subjects in normal control group were selected according to the sex ratio of PVOD patients. Sniffin' Sticks olfactory tests were performed on the subjects, including threshold test (T), discrimination test (D) and identification test (I), and the sum of the above three test scores was the TDI value. At the same time, olfactory event-related potentials (oERPs), trigeminal event-related potentials (tERPs) and taste function test were performed. According to the taste function test, the patients were divided into normal gustation (NG) group and gustatory dysfunction (GD) group. The results of olfaction, taste and intranasal trigeminal nerve function tests were compared among different groups, and the correlation analysis was carried out. SPSS statistical software was used for statistical analysis. Results: GD was present in 14 (33.3%) of 42 PVOD patients with a course of PVOD of 5 (3, 6) months (M (Q1, Q3)). The gustatory function of patients with PVOD was related to gender (r=0.565, P<0.001), smoking status (r=-0.512, P=0.001), duration (r=-0.357, P=0.020) and olfactory function (all P<0.05). The olfactory function of GD group was worse than that of NG group, and the differences of TDI value and T value between the two groups were statistically significant (10.25±4.58 vs 13.35±3.61, 1.54±0.66 vs 2.10±0.88, t value was 2.40 and 2.10 respectively, both P<0.05). The amplitudes of oERPs and tERPs were significantly lower in GD group than those in NG group (all P<0.05). Conclusion: In patients with PVOD, the subjective and objective olfactory function, intranasal trigeminal nerve function and taste function were decreased, and there was a correlation, suggesting that there was a synergistic effect between the chemosensory functions of PVOD patients.

Preliminary study of DTI on cerebral white matter micro-structure of patients with idiopathic olfactory loss / 临床耳鼻咽喉头颈外科杂志

OBJECTIVES@#To investigate the cerebral white matter micro-structure in patients with idiopathic olfactory loss using diffusion tensor imaging (DTI).@*METHODS@#Sixteen patients with idiopathic olfactory loss and sixteen normal subjects matched by age and sex were recruited in this study. Sniffin'Stick olfactory test was performed to evaluate the olfactory function of all subjects. We acquired diffusion tensor images with an echo planar imaging (EPI) sequence from all subject on a 3T scanner. The fractional anisotropy (FA) images were performed using DTI-studio, and bilateral Piriform cortex, Orbitofrontal cortex, Hippocampus and Insula cortex adjacent white matter and Capsula interna were delineated as the region of interesting (ROI), the FA for each ROI was calculated. Independent sample t test analysis was used to compare the FA value of all ROIs between the controls and patients. In addition, correlation analysis between FA value and MMSE score in patients were conducted.@*RESULTS@#Compared with the controls, patients showed significantly decreased FA value in the adjacent white matter of bilateral Piriform cortex, Orbitofrontal cortex, Hippocampus and Insula cortex (0.05).@*CONCLUSIONS@#The patients with idiopathic olfactory loss show the damage of white matter micro-structure in the olfactory center, which could be important for the pathogenesis study and early intervention of idiopathic olfactory loss.