Western Research Centres

CARL is one smart dummy. He works long hours. He won’t fidget or flinch – no matter how inexpertly you prod him. He’s always available to lend an ear – albeit a silicone one. And experts around the world are confident he is head and shoulders above any audiology patient simulator on the market. Developed by Western Engineering graduates in consultation with the National Centre for Audiology, CARL has quickly become an invaluable tool for students and professionals in training, research and product demonstrations. He is also a homegrown success story in R&D and entrepreneurship, with 45 CARLs now with audiology schools, regulators and licencing boards in Europe and North America since the company’s official launch in January. “There are other mannequins in the world, but they’re not designed to do what this one does,” said Rob Koch, Eng’16, MESc (Biomedical Engineering)’18, founder and president of AHead Simulations, based at the Western Research Park. After three years of development, several peer-reviewed publications, and three presentations at international scholarly conferences, research has proved the simulator makes a difference. “Students who used CARL in their training performed better in clinical scenarios than those who didn’t,” Koch said. CARL is an acronym for Canadian Audiology Simulator for Research and Learning. (“The s is silent,” Koch quips.) Its 3D-printed head and custom-moulded ears and ear canals were developed from patients’ CT scans and made of a material with the plasticity and texture of real ears. Because the mannequin is “physiologically and acoustically realistic,” students and clinicians can easily and safely develop their skills in the increasingly complex profession, said Susan Scollie, Director of the National Centre for Audiology and a professor of at Western’s School of Communication Sciences and Disorders. They can see inside the ear, conduct measurements, make proper hearing-aid fittings and tube placements and generate accurate readings about how well the aids are working, she said. The school has six Adult CARLs and a Baby CARL to help students get a head start in helping patients hear. Some CARLs come equipped with specialized software linked to a camera tucked into the mannequin’s hinged head. Calibrated with millimetre-thin sensitivity, Camera CARL offers instant feedback as practitioners navigate in and around the ear. This CARL will even exclaim ‘Ow!’ if the student has done a procedure incorrectly. Pre-CARL lab learning took place, in part, through computer simulations or using other students as practice patients, Scollie explained. But that had limitations: Students had to co-ordinate schedules; safety issues made it impossible to ‘do things wrong on purpose’ as a learning technique; and some hearing aids are dangerous if tested on people without hearing issues. “I found myself saying to students, ‘On a real ear, you would do this …,’” Scollie said. “Now we can pretend that CARL has any degree of hearing loss and he’s fine with that.” The mannequin also allows students to practise when convenient, brush up on their technique and knowledge of anatomy, and even make mistakes – inadvertently and on purpose – without harming the patient. “They can take all the time they want. They can make all the mistakes they want. They can come in any time they want,” Scollie said. “Putting all those things together, having a simulation you can use for learning is safer, more practical and more effective.” CARL started life as Koch’s undergraduate Engineering project in 2016, under the supervision of Electrical and Computer Engineering professor Hanif Ladak. The proof-of-concept prototype was a foam head with an ear on one side. It was awarded the top Electrical Engineering Project of 2016. Further developed as Koch’s master’s project in Biomechanical Engineering, and with guidance from a technology-commercialization course in Engineering, each successive model had new and more refined features. Two validation studies later – and with the addition of computer programming and biomedical engineering expertise from company vice-presidents John Iyaniwura, MESc’17, and Justin Laing, MESc’18 – CARL hit the market.

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Headquartered at Discovery Park, AHead has done more than make inroads into training; it has also changed how some audiologists are tested. Some licencing boards, for example, do competency testing by asking an audiologist applicant to demonstrate skills on the examiner; others require candidates to bring in a friend as test patient. In one case, it took just one botched practice for an audiology training institution in the United States to decide to order a CARL. (During one fitting exercise, a student perforated the practice patient’s eardrum and inserted hearing-aid impression material into the middle ear.) Basic CARLs cost about $2,000, while Camera CARL costs $4,000. There are also accessories, including a carrying case and extra ears. Each refinement and clinical application has come with new potential uses. Recently, CARL was a trade-show model demonstrating a company’s product for safe removal of earwax. The tech’s evolution brings important new understanding of how to help people hear. Baby CARL, for example, is not just smaller but reflects the different anatomy and greater pliability of an infant’s ear. Adult CARL has three different ear sizes and is now offered in a range of skin tones. AHead has had funding support from the TechAlliance and Ontario Centres of Excellence seed funding. Additionally, Koch credits the fledgling company’s success, in part, to its connection with Western Research Parks, proximity to the School of Communications Sciences and Disorders and partnership with the National Centre for Audiology.