CT and MRI in detection of diseases causing hearing loss in adult

Objective:To study the common causes of hearing loss in adults using HRCT and MRI,and to compare the competence of these two imaging techniques in revealing diseases.Methods:HRCT and MRI findings of 7254 adult patients with hearing loss were retrospectively analyzed.The percentage of each disease causing hearing loss and the positive rates of HRCT and MRI were computed.Comparisons of the efficacy in revealing diseases with CT,MRI,and different sequences and sections were undertaken.Results:The total positive rate with HRCT and MRI was 71.66%(5198/7254),and the positive rate with HRCT or MRI alone,or both HRCT and MRI was 75.66%,37.98% and 74.09% respectively.The most common cause was otomastoiditis(79.28%),and the other causes included malformation(8.47%),trauma(3.38%),acoustic neuroma(2.35%),otosclerosis(2.31%),vascular compression of vestibulocochlear nerves(2.17%),tumors and simulating lesions(1.31%) and ossified labyrinthitis(0.73%).MR hydrography of inner ear detected absence of vestibulocochlear nerves better than axial and coronary T2WI(P =0.008 and P=0.006 respectively),and also revealed vascular compression of vestibulocochlear nerves better than axial and coronary T2WI(P=0.002 and P=0.000 respectively).Moreover,MR hydrography of inner ear displayed ossified labyrinthitis better than HRCT(P=0.012) or enhanced T1WI(P=0.002).Conclusion:Otomastoiditis,the most common cause of hearing loss in adults,can be displayed best on HRCT.Nevertheless,the retrocochlear deafness ear can be well shown on MRI,especially on MR hydrography of inner ear technique.Standardization of imaging sequence and methods can increase the identification rates for concerned diseases.