Structural Correlates of Taste and Smell Loss in Encephalitis Disseminata

Felix Alexander Schmidt^1,2, Onder Goktas^1*, Lutz Harms², Georg Bohner³, Katharina Erb³, Bettina Dahlslett¹, Franca Fleiner¹

1 Department of Otolaryngology - Head and Neck Surgery, University of Berlin, Charité Campus Mitte, Smell and Taste Consultation Service, Berlin, Germany, 2 Department of Neurology, Consultation Service for multiple sclerosis, University of Berlin, Charité Campus Mitte, Berlin, Germany, 3 Department of Radiology, University of Berlin, Charité Campus Mitte, Berlin, Germany

Abstract 

Background

Olfactory dysfunction in MS patients is reported in the literature. MRI of the olfactory bulb (OB) is discussed as a promising new testing method for measuring olfactory function (OF).
Aim of this study was to explore reasons for and optimize the detection of olfactory dysfunction in MS patients with MRI.

Materials and Methods

OB and olfactory brain volume was assessed within 34 MS patients by manual segmentation. Olfactory function was tested using the Threshold-Discrimination-Identification-​Test(TDI), gustatory function was tested using Taste Strips (TST).

Results

41% of the MS patients displayed olfactory dysfunction (8% of the control group), 16% displayed gustatory dysfunction (5% of the control group). There was a correlation between the OB volume and the number and volume of MS lesions in the olfactory brain. Olfactory brain volume correlated with the volume of lesions in the olfactory brain and the EDSS score. The TST score correlated with the number and volume of lesions in the olfactory brain.

Conclusion

The correlation between a higher number and volume of MS lesions with a decreased OB and olfactory brain volume could help to explain olfactory dysfunction.