BackroundOnly few therapeutic options exist for patients with refractory sudden idiopathic sensorineural hearing loss (SISHL). Little is known about the efficacy of second-line therapies. Rheopheresis seems to be an effective therapeutic possibility.MethodsBetween 2012 and 2015, 106 patients with SISHL were enrolled in the study, of whom 52 were refractory to initial treatment. As salvage therapy, these patients were offered either 3 sessions of rheopheresis (33 pts) or intratympanic steroid treatment through MicroWick application (19 pts). Pure tone audiometry was performed at diagnosis, at the 1st month and the 1st year during the follow-up.ResultsPatients in the rheopheretic arm had higher hearing loss than in the MicroWick arm (81% vs. 52%, p = 0.04). In spite of this, there was a significant improvement for patients in the rheopheretic arm (27% of hearing loss reduction, p < 0.001) after the 1st month and this remained unchanged during the 1st year, while no improvement was seen in the MicroWick arm (0% of hearing loss reduction, p = 0.424). We found no predictive factor for steroid-failure in first-line therapy. Older age (p = 0.003), presence of vertigo (p = 0.006) and more profound initial hearing loss (p < 0.001) were identified as negative prognostic markers.ConclusionRheopheresis can be used as a potentially effective and safe salvage therapy for patients with cortico-refractory SISHL.