Iona Ross BME 281 October 18, 2011

 More than 600 million people worldwide (10%) suffer from hearing impairments  250 million people worldwide have moderate to severe hearing impairments  # of people with hearing loss in the U.S has doubled in the past 30 years  By 2015, it is predicted that an estimated 700 million people worldwide will suffer from hearing impairments

 3 parts to the ear:  External (pinna) – collects and directs sound through ear canal to ear drum membrane  Middle (2 major parts)  Ear drum – detects sounds – sends them to ossicles  Ossicles – amplify sounds – send them to inner ear  Inner (cochlea)  Transmits sounds along auditory nerve to brain via electrical stimulation

 Conductive  Sound does not reach inner ear  Sensori-neural  Problems with transmission of signals from cochlea to brain  Abetted by Bionic Ear

 19 th century  Count Volta and Duchenne of Boulogna  Stimulated hearing - electical stimulation  1957  Djomo and Eyries  Implanted a single electrode attached to induction coil into head of a patient – result: patient heard  1960s – 70s – multiple electrode output best  1978  Dr. Graeme Clark inserted first Bionic Ear into Rod Saunders – worked! Dr. Graeme Clark

 Nucleus® 22 Cochlear Implant System  22 channels for current  Template  Made with help from Univ. of Australia, fed government, and Nucleus – partnership  Nucleus® 24 Cochlear Implant System  24 channels for current – more precise hearing  NRT technology

 2 internal components  Array of electrodes  Transmitter-receiver  3 external components  Microphone  Speech processor  Transmitting coil  NRT technology

1) Microphone Detects and sends sound to speech processor 2) Speech Processor Sound to electrical code Sent to transmitting coil via cable 3) Transmitting Coil Radio waves - through skin to implant 1) Microphone Detects and sends sound to speech processor 2) Speech Processor Sound to electrical code Sent to transmitting coil via cable 3) Transmitting Coil Radio waves - through skin to implant

4) Implant package Decodes entire signal Sends required amount of current - electrodes in cochlea 5) Electrodes in cochlea Nerve endings stimulated Message sent to brain 4) Implant package Decodes entire signal Sends required amount of current - electrodes in cochlea 5) Electrodes in cochlea Nerve endings stimulated Message sent to brain

TODAYFUTURE 1) Helps mainly those that have lost hearing b/c age 2) Inconvenient device 3) Unclear signals to brain at times 4) Costly procedure 1) Young children with little or no hearing early on 2) Entirely internal device (microphone first) 3) Improve clarity 4) Decrease cost via maybe requiring less audiologist appts?

 Australian Academy of Science. “Cochlear Implants – wiring for sound”  Traynor, Bob. “The Incidence of Hearing Loss Around the World” 6 April /2011/incidence-of-hearing-loss-around-the-world/  ThePowerhouseMuseum\.I USED SEVERAL ARTICLES AND PICTURES FROM THIS GENERAL SITE. m/hsc/cochlear/the_cochlear.htm  “Cochlear Implantation and Quality of Life in Deafness”. Damen, G. W. J. A.,Mylanus E.A.M, Snik A.F.M. Handbook of Disease Burdens and Quality of Life Measures.. G. W. J. A.,Mylanus E.A.M, Snik A.F.M.