Zde - 2. lékařská fakulta - Univerzita Karlova

P-34. MORPHOMETRIC ANALYSIS AND DTI OF THE AUDITORY CORTEX IN MAN – CHANGESWITH AGINGProfant O. 1,3 , Škoch A. 2 , Tintěra J. 2 , Balogová Z. 1,3 , Ibrahim I. 2 , Syka J. 11 Department of Auditory Neuroscience, Institute of Experimental Medicine, Academy of Sciences ofthe Czech Republic, Prague, Czech Republic; 2 MR Unit, Institute of Clinical and ExperimentalMedicine, Prague, Czech Republic; 3 Dept. of Otorhinolaryngology and Head and Neck Surgery, 1stFaculty of Medicine of Charles University, University Hospital Motol, Prague, Czech Republic;Supervisor: Prof. MUDr. Josef Syka, DrSc.Introduction: One of the most dominant cognitive declines in the ageing population representshearing loss (presbycusis). The dominant reason for presbycusis is hypo functional inner ear with lossof outer hair cells. However, recent findings showing a deterioration in the processing of temporalfeatures of sound as well as a decline in the speech understanding point toward central componentsof presbycusis.Aims: In our study we focused on the possible changes in the auditory cortex that accompanypresbycusis.Materials and Methods: Parameters of hearing function were assessed in a group of healthy youngcontrols (YC), a group of elderly with normal presbyacusis (EC) and a group of elderly with expressedpresbyacusis (EP) and then their auditory system was examined using Siemens Trio 3T magneticresonance. For Diffusion tensor imaging (DTI), tractography of auditory pathway from the inferiorcolliculus (IC) to HG with subsequent analysis was performed. Morphometric analysis was performedwas performed using EPI sequence. Morphometric analysis (Gray matter volume (GrayVol), area ofgyral surface (SurfArea) and average thickness of gray matter (ThickAvg)) for specific ROIs (Heschl´sgyrus – HG and planum temporale –PT, visual cortex) were computedResults: Significant decrease of ThickAvg in groups EC, EP with respect to YC was found for HG andPT. The analysis showed significantly higher SurfArea on the left side with respect to the right side inHG and PT in all groups. The decrease of the GrayVol for groups EC, EP with respect to YC andhigher GrayVol on the left side was in accordance with the ThickAvg and SurfArea results. Visualcortex showed only a non-significant trend in a decrease of the thickness in both EC and EP. Theresults from DTI indicated a tendency for increasing L1 in EC and EP with respect to YC in auditorypathway, observable to a greater extent on the right side. No differences between EC and EP wereobserved in any of the morphological or diffusion parameters.Conclusions: The results demonstrate typical left-right asymmetry of the primary auditory cortex andplanum temporale and indicate the degree of the age-related atrophy of these structures that does notdepend on the level of hearing dysfunction and is not present to such extent in the primary visualcortex.Support: Supported by grants 00023001 IKEM and GACR P304/10/187266