Comparison of gadolinium-enhanced MRI of the inner ear with definite Meniere's disease in the detection of endolymphatic hydrops between intratympanic and intravenous injection.

Objective: We aimed to compare the success rate of the inner-ear visualization and actual endolymphatic hydrops (EH) detection rate of gadolinium-enhanced MRI in ears with definite Meniere's disease (dMD) with intratympanic versus intravenous injection.

Methods: 122 ears with dMD were included and divided into the intratympanic (IT) administration and intravenous (IV) groups. 38 ears in the IT group were evaluated by 3D-real IR and 3D-FLAIR sequence scans 24 h after injection of 8-fold diluted gadolinium. 84 ears in IV group were evaluated by i3D-real IR sequence scans 4 h after intravenous gadolinium administration. The success rate and the detection rate of EH were evaluated and analysed.

Results: The i3D-real IR sequence in the IV group had a higher success rate (100%) than did the 3D-real IR (76.32%) and 3D-FLAIR (84.21%) sequences in the IT group. The actual EH detection rate in the IV group (98.81%) was significantly higher than that for the 3D-real IR (76.32%), 3D-FLAIR (78.95%) or 3D-real IR + 3D-FLAIR (84.21%) sequences in the IT group. The presence of EH could not accurately be assessed in 15.79% of ears in the IT group due to weak perilymph enhancement. After exclusion of these ears, the IT and IV groups showed similar EH detection rates.

Conclusion: The insufficient success rate of IT method reduced its actual EH detection rate. Using i3D-real IR, the IV method offers the higher success and actual EH detection rates, which provides a reference to the individualized choice of gadolinium-enhanced MRI.