*3.3. Success of Reimplantation*

Reimplantation resolved the problem driving the intervention in 94% of patients. Four patients did not benefit from reimplantation (Table 3). The main hypothesis explaining these results were suspicion of auditory neuropathy spectrum disorder, scala vestibuli insertion of the electrode array, suboptimal speech rehabilitation, and initial diagnostic error. Patient 2 presented with ossification of the basal portion of the scala tympani. The reinsertion of the electrode array in the scala tympani was not possible despite several attempts of cochleostomies. The new electrode array was thus inserted in the scala vestibuli (complete insertion), but presumably had led to the decrease in auditory performances (−26%). For two other patients, partial reinsertion into the scala tympani occurred (the etiology was post-meningitis in one case, and unknown for the other case). Aside from these patients, complete reinsertion in the scala tympani was achievable in 96% of the cohort. For patient 3, the speech rehabilitation program was not followed because of the presence of severe tinnitus after reimplantation. The tinnitus was associated with anxiety and depression-like symptoms.

**Table 3.** Description of patients receiving no benefit from the cochlear reimplantation. NSHL: non-sensory hearing loss; SHL: syndromic hearing loss.


<sup>1</sup> Epilepsy and dysarthria; <sup>2</sup> Usher syndrome (type 1); <sup>3</sup> Pain around the processor.
