Hope for hearing: Cochlear implants Cochlear implants are electronic hearing devices An implant does not restore normal hearing and is very different from a hearing aid About 210,000 children and adults around the world have received these implants (CNN) -- Six years ago Hope Koch's life began to change dramatically. A pianist since the age of 5, she knew something was wrong when listening to music became difficult. That's when the 70-year-old wife and mother of three clearly remembers her hearing loss began. That's the first thing that got all jumbled. I couldn't understand it anymore and then I couldn't understand my children, my adult children and then the grandchildren came along and I missed out what they were saying. At first she didn't tell anyone, not even her husband Frank. She pretended nothing was wrong. But soon she could no longer understand movies, and needed closed captioning. She lost her confidence and began to shy away from people because she couldn't understand them. Eventually she stopped answering the phone. "I felt like I was putting them to a lot of trouble to have to repeat and repeat," Koch said. All of the things that you enjoyed doing, you shied away from. Koch saw an audiologist and was fitted for hearing aids. They helped, for a while. But the hearing loss continued. At the end of last year, her audiologist presented her with one final option. Since the hearing aids couldn't help her any more, he suggested she consider a cochlear implant. Cochlear implants are electronic hearing devices for people with profound deafness or severe hearing loss who get no benefit from a hearing aid. There is an external part that is worn behind the ear with a microphone that picks up sounds from the environment, a speech processor and a transmitter that gets signals from the processor and turns them into electric impulses. It is attached to a receiver and electrode system which is surgically implanted into the inner ear. It's typically done as an outpatient procedure. An implant does not restore normal hearing and is very different from a hearing aid. Hearing aids amplify sound so that damaged ears can hear them. Implants bypass the damage and directly stimulate the auditory nerve which then sends the signals to the brain. Koch had the surgery at the University of Maryland Medical Center in Baltimore in September. It was easy, comfortable, the recovery was good. I mean I'm very pleased with it. I had no negative effects from the surgery, no pain. CNN was there when her implant was activated for the very first time. A range of emotions crossed her face -- then came tears. "I thought maybe I'll be disappointed today, maybe it won't work for me," Koch said. I was straining to hear something, anything and when I could hear something in this ear that has been without any sound for years, it was overwhelming that way, and then to hear my voice, I'm listening to it talking and it's just so, it's just wonderful. Koch's husband Frank has high expectations for this implant. That we can go back to the normal way we use to be and spend the rest of our years that way. Our expectations, 12 weeks from now or 12 months from now is she's going to be totally normal and that's what we're hoping and that's where she's going to go. Koch is sure of it. The quality of life is gonna be so good now, it'll be good again. Dr. Ronna Hertzano, assistant professor at UMMC, did Koch's surgery. She says over the last few years, more and more seniors are choosing cochlear implants to combat their hearing loss. In fact the oldest person she performed the surgery on was in his late 80s. She even knows of cases involving folks in their 90s. It's unknown how many elderly patients get a cochlear implant, but according to NIH, about 210,000 children and adults around the world have received these implants. According to the FDA, in the United States roughly 42,600 adults and 28,400 children have received them. "It seems that more senior individuals are aware that there are alternatives to hearing aids, and once the hearing aids are not sufficient, they can improve their hearing and almost regain most of their hearing ability at least when it comes to speech, with a cochlear implant," Hertzano told CNN. We used to do older individuals just maybe once or twice a year, and now I would say that we do older individuals maybe every month. At UMCC, surgeons perform about 50 procedures a year. Hertzano, an expert on the devices, has done about 100 implant surgeries. She says anyone who has hearing aids, but cannot understand at least 50% of sentences spoken in normal conversation is a good candidate. Once implanted, she says, many implantees can understand up to 90% of sentences. When Hertzano met Koch she could only understand 20% of sentences in a conversation and was using visual cues. Hertzano says age is not a factor in the surgery, but the candidate must be healthy enough to undergo surgery with general anesthesia. And they can't have dementia, which could make it difficult to adapt to learning to understand speech with a cochlear implant. According to The American Academy of Otolaryngology-Head and Neck Surgery, it's rare that a patient does not benefit from a cochlear implant. But the procedure can be pricey. The total cost, they say, can be as much as $100,000 for the evaluation, surgery, the device itself and the rehabilitation. However, most insurance companies and Medicare will cover that cost according to AAO-HNS. For Koch, it was all worth it. She says she's hearing much better again, but at the same time acknowledges she still has a way to go. It's been a learning experience. This is going to take at least a year or longer. It gets down to your brain retraining itself. This year, the holiday season was extra special -- she heard her family's voices for the first time in years. It's wonderful to hear them speak. It was fantastic, the best Thanksgiving/Christmas that I've had in a number of years. My sons, they have low voices, but I can hear them now. I'm understanding everything better. It's just a world of difference.