Correlation Between Clinical Features Of Ménière’s Disease And Hippocampal Volume

Objective:To retrospectively analyze the relationship between disease stage,vestibular function,endolymphatic hydrops(EH)and hippocampal volume in patients with Meniere’s disease(MD),and to explore the correlation between vestibular function and hippocampal volume in MD.Methods:Detailed clinical data of 99 patients with unilateral MD admitted to vertigo disease department of Shandong Provincial ENT Hospital from February 2021 to April 2022 were collected.All patients met the diagnostic criteria for MD published by the Bárány Society in 2015.The mean hearing threshold at 500 Hz,1000 Hz and 2000 Hz was used for staging.Stage 1 and 2 were defined as the early-stage groups,and stage 3 and 4 were defined as the late-stage groups.There were 50 cases in the early-stage group,49 cases in the late-stage group,and 50 cases in the normal control group.MD patients completed pure tone audiometry(PTA),caloric test,video-head impulse test(v-HIT),ocular vestibular evoked myogenic potential(oVEMP),cervical vestibular evoked myogenic potential(cVEMP),the sensory organization test(SOT),the functional level scale(FLS),and the hospital anxiety and depression scale(HADS).MD patients were graded for EH by magnetic resonance imaging(MRI)with intravenous injection of gadolinium contrast agent.All study participants perfected three-dimensional(three-dimensional,3D)cranial MRI and acquired hippocampal imaging data.The hippocampus was mapped using 3D Slicer software.SPSS 26.0 software was applied to statistically process the data.Results:1.In the control,early and late groups,there were no group differences in age and gender,which were not statistically significant(P=0.185;χ2=1.075,P=0.584).2.In the early and late groups,there were no differences in affected ear side(χ2=1.953,P=0.162)and duration of disease(z=-1.655,P=0.098);no differences in FLS(z=-1.206,P=0.228)and HADS(z=-1.420,P=0.156;z=-1.523,P=0.128).There were no differences in cVEMP(χ2=0.876,P=0.349)and oVEMP(χ2=3.692,P=0.055);PTA(t=-16.655,P<0.001),caloric test(z=-3.643,P<0.001),v-HIT(z=-2.763,P=0.006;χ2=8.731,P=0.003),SOT vestibular equilibium score(ES)(z=-2.510,P=0.012)and SOT composite ES(t=4.000,P<0.001)were statistically different between groups;cochlear EH grading(z=-4.015,P<0.001)and vestibular EH grading(z=-3.857,P<0.001)were statistically different between groups.3.MD staging and hippocampal volume:there was no difference in hippocampal volume between the control group and the early group(P=0.073 for left hippocampal volume;P=0.310 for right hippocampal volume;P=0.167 for mean hippocampal volume on the left and right sides).There was a statistically significant difference in hippocampal volume between the control group and the late group,and the hippocampal volume in the late group was smaller than that in the control group(P<0.001;P<0.001;P<0.001).Hippocampal volumes were statistically significant between the early and late groups and were smaller in the late group than in the early group(P<0.001;P=0.001;P<0.001).Hippocampal volumes on both the affected and healthy ear sides were statistically different between the early and late groups(t=4.669,P<0.001;t=3.428,P=0.001)and were smaller in the late group than in the early group.4.Factors influencing MD staging:mean hippocampal volume(P<0.001,OR=0.045,95%CI=0.008-0.240,AUC=0.765)and SOT composite score(P=0.024,OR=0.902,95%CI=0.825-0.986,AUC=0.708)had a significant effect on MD staging.5.Factors influencing mean hippocampal volume:in the early group,duration of disease and caloric test may affect mean hippocampal volume(P=0.023;P<0.001).In the late group,age,sex,and vestibular EH may affect mean hippocampal volume(P=0.007;P=0.002;P=0.018).Conclusion:Hearing and vestibular function are more impaired,EH is more severe,and hippocampal volume atrophy is more pronounced in the late group.As MD patients progress,vestibular function decreases,EH worsens,the hippocampus becomes atrophied,spatial orientation navigation function decreases,and the risk of imbalance and falls increases.Clinicians should provide early interventions for Vestibular compensation and balance in MD patients to reduce the occurrence of falls and improve the quality of life.