A patient with bilateral profound SNHL receives a cochlear implant. During programming, the audiologist finds that the patient requires extremely high stimulation levels. Which electrode position within the cochlea leads to this finding?

• A Scala tympani placement at the basal turn
• B Scala vestibuli or translocation of the electrode ✓
• C Tip fold-over (electrode kinking near the helicotrema)
• D Correct perimodiolar placement with platinum electrodes

Explanation

Scala vestibuli placement or electrode translocation (crossing the basilar membrane from scala tympani to vestibuli) results in electrodes being farther from the modiolus and spiral ganglion cells, requiring higher stimulation levels (elevated threshold levels). Scalar translocation is associated with worse outcomes and higher power consumption. HRCT/CBCT post-implant can detect translocation. Perimodiolar designs aim to keep electrodes close to the modiolus to reduce stimulation thresholds.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.