Surgical procedures for a minimal invasive approach of cochlear implantation aiming for immediate initial mapping.

<p><i>(</i><b><i>A</i></b><i>)</i> After draping and sterilization, a 2.5 to 3 cm skin incision was made in the post-auricular region at a distance of about 2 cm away from the posterior wall of external ear canal. <i>(</i><b><i>B</i></b><i>)</i> To avoid possible tissue injuries, four custom-made hooks instead of self-retain instrument (e.g. mastoid retractor) were used to expose the cortex of mastoid bone. <i>(</i><b><i>C</i></b><i>)</i> A thin piece of cortex bone (about 10×10×3 mm in size) harvested before the mastoidectomy was used as a shielding coverage for the protection of the wire inside mastoid cavity.