Expert interviewed: Cao Keli, Director of Cochlear Implant Center, Peking Union Medical College Hospital Specialties: Diagnosis, treatment and micro-neuro-otology surgery mainly for deafness. Clinic hours: Tuesday all day and Thursday afternoon (East Hospital of Peking Union Medical College Hospital) “Two ears are good!” At the Cochlear Implant Center of Peking Union Medical College Hospital, five-year-old boy Zhang Ke (a pseudonym) answered without thinking when asked whether it was better to have two cochlear implants or one. Cao Keli, Department of Otolaryngology, Peking Union Medical College Hospital Two years ago, Zhang Keli received a Cochlear implant from Australia in his left ear, and his speech skills were greatly restored. Six months ago, he received another Cochlear implant in his right ear, and now his hearing has improved even more, and he is able to distinguish sounds well in noisy environments. The director of the Cochlear Implant Center at Peking Union Medical College Hospital stroked the five-year-old boy’s head and said to the reporter with a smile, “Bilateral cochlear implants allow hearing-impaired patients to hear more clearly, locate sounds more accurately and be less affected by noise.” Restoring 360-degree hearing Professor Cao, who is known as the first person to have a cochlear implant in China, told reporters, “All along, patients with severe and profound deafness have been implanted with unilateral cochlear implants to restore their hearing, but there are many unsatisfactory aspects of unilateral implantation.” The biggest problem that patients with monaural cochlear implants encounter in their lives is a lack of accurate sound localization and a relatively high error rate. Because the sound source is fixed, there are various barriers to acquiring hearing through only one ear, and even in a quiet, echo-free environment, the ability of monaural implant patients to distinguish speech is not ideal. If only one ear is functioning properly, it can be challenging to listen to the sounds around you, says Professor Cao. This is because the head blocks sounds from different directions, while cochlear implants in both ears help provide the 360-degree hearing that natural sounds are supposed to provide. Learn to speak faster For our hearing impaired population, the advantages of bilateral implants are even more pronounced because Chinese is a tonal language system, and it has been observed clinically that children with bilateral cochlear implants can learn to speak faster for Chinese language learning. Professor Cao explained that the tone of Chinese language poses a great difficulty for children who are born with severe neurological deafness, while children with bilateral implants are able to perceive low flat tones more sensitively, so they learn faster and with better results. Children with cochlear implants in one ear take at least 3 to 4 months to reach basic listening skills, while binaural implants take only 1.5 months. Currently, Peking Union Medical College Hospital has done 12 cases of binaural cochlear implants. Don’t wait more than two years between cochlear implants. Professor Cao Keli recommends that families who are able to do so should try to have cochlear implants in both ears at the same time. In cases where one ear is implanted first and the other is implanted later, the interval should not exceed two years. Even if the cochlear implant is successful, the results will not be as good as if the cochlear implant was implanted in both ears at the same time because of the central hearing deprivation. Of course, even if the interval exceeds two years, the results are still better than with unilateral implants. Younger children with shorter intervals between bilateral device implants have better development of directional hearing skills, while those with longer intervals between bilateral cochlear implants also have development of directional hearing skills, but take longer to recover. Currently, Auclear is the world leader in bilateral cochlear implants, with over 10,000 patients worldwide having received bilateral Cochlear implants as of 2010. Auclear also holds a leadership position in basic and clinical research in the field of bilateral cochlear implants and will continue to conduct intensive research and development in this area.