MRI in diagnosis Meniere’s disease: what is the evidence?
Reviewed by Victor Osei-Lah

The utility of magnetic resonance imaging (MRI) in the diagnosis of Meniere’s disease (MD) has attracted a lot of interest recently. It is well accepted that the saccule is the most common vestibular organ affected by endolymphatic hydrops (EH) and research has focused on in-vivo visualisation of EH in the saccule and cochlear on MRI. While this is an exciting area of research, there have been conflicting findings in the literature. The authors conducted a systematic review of current evidence using the PRISMA criteria. From 52 individual articles, 13 case control studies comprising 833 individuals were included in the analyses. The authors focused on the physical basis of MRI sequences for the hydrops protocol, the pitfalls and quality of the criteria used in the individual studies. In the majority of publications, demonstrating EH on MRI relied on either inversion recovery (IR) sequences or heavily-weighted T2 gradient echo sequences. The majority of publications used the former. Six studies involved 3D-FLAIR, two each of 3D-CISS and T2w and one each of CISS, T2w-FIESTA and T1w/T2w. Apart from the variability in the protocol of the contrast diffusion method (gadolinium-based contrast agent - GBCA), there was a huge variability in how EH was graded by different researchers. For instance, grading EH into three categories: none, mild and significant, both in the cochlea and the vestibule; and saccule to utricle ratio inversion (SURI). The authors noted that the most common sequence to visualise EH was 3D-FLAIR combined with intravenous GBCA. However, the inversion time, which is critical to discriminate perilymph from endolymph, was not described in most of the 3D-FLAIR studies. Another conclusion was that EH can be reliably visualised in the saccule using the SURI method. To confuse the role of MRI in MD, the authors point out that studies have demonstrated EH in patients with vestibular migraine, acute low frequency sensorineural hearing loss (without vertigo), tinnitus regardless of hearing loss, and autoimmune inner ear disease. The review sheds light on the complexities of MRI in the diagnosis of MD but it is clear more research is needed.

Systematic review of magnetic resonance imaging for diagnosis of Meniere disease.
Jose A. Lopez-Escamez JA, Attyé A.
JOURNAL OF VESTIBULAR RESEARCH
2019;29:121-9.