Isolated enhancement of the superior semi-circular canal on inner ear MRI: acute vestibular syndrome or superior semi-circular canal dehiscence?

PURPOSE: Recently, it has been reported that patients with acute vestibular syndrome (AVS) could present a marked enhancement of the semi-circular canals, involving mostly the superior semi-circular canals on delayed inner ear MRI.

METHODS

We reported one patient having AVS and another one having superior semi-circular canal dehiscence syndrome (SCDS) who underwent delayed inner ear MRI performed 4 h after contrast media administration.

RESULTS

On delayed inner ear MRI, a marked enhancement of the superior semi-circular canal was observed in both patients. Although the clinical presentation is clearly not the same, the co-existence between these two disorders is possible. For this reason, in patients with AVS, the presence of a marked enhancement of the superior semi-circular canal should rule out the presence of a co-existing SCDS on temporal bone CT, particularly if the patient reported cochlear symptoms such as pulsatile tinnitus and/or autophony.

CONCLUSION

To our knowledge, this is the first report showing this finding on delayed inner ear MRI in a patient with SCDS. In AVS patients, this radiological anomaly could be particularly disturbing and should rule out the presence of a co-existing SCDS.