Having been found in 3%-21% patients with congenital sensorineural deafness, cochlear nerve deficiency (CND) is defined by a small or absent cochlear nerve. This book describes the updated information on the embryology, pre- and post- operative auditory, electrophysiology and vestibular aspects of CND. What's more, the cochlear implantation (CI) strategy and CI outcomes as well as comparison with normal patients will be discussed in details with selected cases and high resolution illustrations. It will be a valuable reference for otologists, audiologists and practitioners who would like to understand more about CND and choose optimal clinical strategy of CI surgery for CND.