Hydrops imaging: Influence of Inversion Time on endolymphatic hydrops evaluation
Publié le dimanche 21 mai 2017 - Lien permanent
In this new study, we aimed to compare two MRI sequences for hydrops evaluation, only different in Inversion Time (TI), in patients with cochlea-vestibular symptoms, and by controlling the study with healthy volunteers. We would mention that the effect of raising the TI would increase the global fluid signal, for example in the cerebrospinal spaces as well. Yet, this is not sufficient to explain the local variation of the inner ear fluids given that we report 2 volunteers and 2 patients without endolymph to perilymph ratio variation between the two sequences.
We further demonstrate the lack of robustness of
the semi-quantitative method of grading, highly dependent for sequence
parameters, by contrast with saccular hydrops evaluation.
Illustrations of main findings are available here.
Out of the scope of this article, I put your attention on the influence of the Echo Time (TE). By contrast with the TI, the endolymph/perilymph ratio remains stable when varying the TE but interestingly, IR sequences with high TE values allow to better distinguish contrast media accumulation, promising for semicircular canals' evaluation, as illustrated on the picture (thanks to David Chechin, Philips research engineer, for the collaboration).
Publié le dimanche 21 mai 2017, 10:06 - Lien permanent