$1 Million Grant - A Timely Boost
for Screening the Hearing of Infants.
Courtesy of the
Hearing Foundation of Canada
A grant from Alberta Health and Wellness to the Canadian Network for Universal Newborn Hearing Screening at the University of Calgary Faculty of Medicine (UNHS) is called an important first step toward recognizing the importance of catching hearing loss early in life.
Canada’s infant hearing loss screening resources have been a long-time source of frustration for the country’s health professionals. But a recent $1-million grant from Alberta Health and Wellness, to the Canadian Network for Universal Newborn Hearing Screening at the University of Calgary Faculty of Medicine (UNHS) may be the first step toward changing all that. The grant finally gives long overdue attention to the necessity of recognizing hearing loss very early in life and to UNHS, which began its efforts in the late seventies.
Created by Dr. Joseph Dort, associate professor of surgery at the university, the goal of the UNHS is to establish a nation-wide testing program that will detect hearing loss in newborn babies. "We are hoping to begin testing babies in the fall," Dr. Dort said. The pilot project will run over three years. "Our goal is to implement [the testing] on a wider scale and collect data to determine how cost effective and beneficial the project is."
Dr. Dort will be working in collaboration with co-investigators, Dr. David Brown and Dr. Reg Sauve, to establish the procedure at various Alberta health centres. Data collected will be used to create a model that could be applied nationally.
Although many European countries and 24 American states have newborn screening programs, this Alberta-wide initiative is a first in Canada. The researchers will be developing and implementing the UNHS program in collaboration with regional health authorities across the province. This community-based program is designed to provide multiple contact points and broaden the access that families have to these services. It is also intended to reduce costs and save time in identifying children with hearing loss.
Currently, infant hearing screening is a hit-and-miss proposition. While some hearing impaired babies are luck enough to be born in a hospital where hearing tests are performed just after birth, putting them on the road toward hearing and developing normal language skills, too many others are not. Selective screening is often the reason. Of the 35 independent programs currently offered in Canada, most target only newborns considered to be at high risk. These include premature babies, those born after difficult pregnancies, babies weighing less than five pounds, or those with a family history of deafness. Yet, it has been proven that half the babies born with hearing loss are still not being identified.
That is why hearing-health professionals have been lobbying for systematic, universal screening. Another such advocate is Dr. Andree Durieux-Smith, professor of audiology and vice dean for research at the University of Ottawa. She noted the progress being made in other parts of the world while suggesting it’s time Canada followed suit. "In the United Sates, they have what’s called the Joint Committee on Infant Hearing, which is multidisciplinary," said Dr. Durieux-Smith. "It includes pediatricians, otolaryngologists, audiologists, speech and language pathologists, educators and so forth. It would be nice to have a similar kind of structure here," she said.
"Children are paying a price," added the doctor. "We know hearing loss is a hidden handicap, and if you don’t actively screen for it, you will only identify it when the child is not developing speech and language much later. That’s why we’re now moving towards universal hearing screening."
Indeed, it is widely agreed by experts that early detection hearing loss promotes the development of speech and language, which is the foundation for future academic, vocational and psychosocial health.
Scientific evidence suggests there’s a use-it-or-lose-it impact, with the first six months of a baby’s life being crucial. The brain is developing so rapidly during this time that if the auditory system is not stimulated, the neural tracks and neural clusters will not develop.
"We know through animal studies that there are changes in the central nervous system when there isn’t adequate sensory input," explained Dr. Durieux-Smith. "So, it’s absolutely critical to identify these children early and provide them with auditory input."
Keith Christopher, executive director of the Canadian Speech and Hearing Association, based in Ottawa: "If you can detect a hearing loss early, you can accommodate, so that these children will end up functioning virtually normally. If you miss it, then its much more difficult to back track and pick up what they have lost."
Christopher points out that up until the early 1980s, Canada used to be in the lead where early hearing loss screening was concerned. "But now we have dubious distinction of being at the bottom the pile," he lamented.
At that time, a Health Canada task force produced an information kit that was distributed across Canada to family physicians and pediatricians to alert them to the symptoms of hearing loss in children. "Essentially we haven’t moved since," says Dr. Durieux-Smith. "Somehow, universal screening is no longer on the agenda of the federal or provincial governments. "There has to be a co-operative effort between the provincial and federal groups."
If and when the governments and health professionals do begin working together, the technology will already be in place, according to Dr. Krista Riko, audiologist and director of the otologic function unit at Mount Sinai Hospital in Toronto. "We have two electro-physiologic techniques that can be used to test babies of any age, from newborn on up," explained Dr. Riko. Oto-acoustic emissions is the one that has been used for screening more than anything in the recent past.
The machine sends a sound down the ear canal into the inner ear into the hair cells, and if they’re healthy, they bounce back and echo; that echo can then be measured.
The other technique that is used more diagnostically is called auditory brain stem response (ABR.). This is a technique where EEG can be measured by pasting electrodes on the baby’s head. "EEG does in fact change if you hear a particular kind of sound," Dr. Riko notes. A computer is used to analyze the changes in the baby’s brainwaves and "those changes are enormous," Dr. Riko explains. "If there is a response to the sound, the computer will extract that response out of the background noise. So if the baby hears, we see a very characteristic change in the shape of the [brain] pattern."
"So, the technology is there," Dr. Riko concludes. "Now, what we need is the infrastructure to go out there and do it."
Dr. Dort and Dr. Brown are confident that the pilot project will be a first step toward universal testing across Canada. "I think what’s going to happen is our ability to start this will give other people in other provinces even more ammunition," Dr. Dort said.
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