Over 615,000 people in the United States alone are affected by Meniere’s disease, a problem of the inner ear that can lead to vertigo (dizziness) and hearing loss, and many more experience sudden hearing loss caused by sensorineural hearing loss (SNHL), cochlear hydrops, autoimmune inner ear disease, and vestibular schwannoma tumors. Unfortunately, the underlying pathology of these various afflictions is poorly understood, and little can be done to help these patients beyond amplifying sound through the use of hearing aids.

However, John Oghalai, MD, professor and chair of otolaryngology-head and neck surgery and the Leon J. Tiber and David S. Alpert Chair in Medicine at the Keck School of Medicine, was recently awarded an R01 grant for his research project on “OCT Imaging of the Human Inner Ear,” which he hopes will bring researchers and clinicians one step closer to a better understanding of how the cochlea works – a snail-shaped, fluid-filled organ in the inner ear. Because this is frequently where hearing loss originates, a better understanding of how the cochlea works could be essential to empowering scientists to figure out how to prevent hearing loss from worsening and how to restore hearing for as many patients as possible. Currently, CT and MRI scans can give clinicians a picture of the gross structures of the inner ear, but they provide little information on the more delicate tissues that make up these structures, and invasive procedures like surgery can carry with them a variety of risks. Optical coherence tomography (OCT), on the other hand, is a noninvasive imaging technique that uses low power laser light to capture high-resolution, 3D images, making it an ideal option for further research.

A journey of passion and innovation

Oghalai grew up in Madison, Wisconsin and became interested in circuits and computer programming at a young age. He was an early adopter of the Apple II computer, which came out in 1977, and when he enrolled at the University of Wisconsin-Madison for a combined undergraduate-medical school program, he studied electrical engineering while simultaneously fulfilling his pre-med requirements. As an undergraduate, Oghalai had his first introduction to otolaryngology when he was assigned to a lab focused on hearing research. He discovered that, in many ways, the ear is like a big circuit, and while he initially imagined that he would focus on neurology in medical school, studying how the brain processes sound, he later realized that if he went into otolaryngology, he could focus more specifically on the auditory system while also having the opportunity to do surgery. He emphasizes that majoring in electrical engineering as an undergraduate helped to prepare him for the intense quantitative requirements of scientific research that would become so essential to his career. In addition, because he had been admitted to a special combined undergraduate-medical school program and therefore did not have to worry about applying to medical school after college (or about having the extremely high GPA that would require), he was able to select a “riskier” major that ultimately allowed him to bring a more expansive and multidisciplinary perspective to the medical profession.

One of Oghalai’s most consequential – and fortuitous – experiences over the past several decades of his career was meeting Brian Applegate, PhD, while he was an assistant professor at the Baylor College of Medicine. Applegate, who at the time was an assistant professor of biomedical engineering at Texas A&M University, was using lasers to image the eye, and together, Oghalai and Applegate would collaborate on using OCT to instead look at the deeper structures of the ear. Similar to ultrasound technology, OCT gave Oghalai and Applegate a noninvasive means by which to look at the tissues in the inner ear, but OCT produced much higher-resolution images than ultrasound.

Over the past decade or so, they have used OCT for their research to image the inner ear in animals like mice, guinea pigs, gerbils, and chickens. Previous research techniques required making a hole in the bone for a direct view, but this experimental approach often caused hearing loss. However, with OCT technology, they were able to image the tissues and cells within the inner ear right through the dense bone that surrounds it, making it a safe option with no risk to hearing or balance. This has laid the groundwork for Oghalai’s innovative research proposal to use OCT to image the human inner ear by fitting a device onto an operating microscope so that it can be easily used during surgery, taking a complete volume stack of images in less than one minute such that the time a patient is under anesthesia is not unduly extended.

Advancing hearing research and clinical practice at USC

In 2017, after seven years as a professor at the Stanford University School of Medicine, Oghalai moved to USC to become chair of the Caruso Department of Otolaryngology at the Keck School of Medicine. As Oghalai describes it: “I saw moving from Stanford to USC as a tremendous opportunity. The auditory research group was incredible, and there was a significant endowment designated to grow the research to cure hearing loss. The clinical faculty were also excellent, and there were a lot of opportunities to grow satellite clinics throughout the greater Los Angeles area. Finally, the training programs are very strong, including the otolaryngology residency and the medical school.” Oghalai’s primary research and clinical goal is to get his team’s OCT device out into clinics as soon as possible so that it can be used by clinicians as a diagnostic tool, and as department chair, he recognizes the importance of promoting the development of the department’s faculty and trainees so that they can build their professional careers in accordance with their own goals.

As Oghalai says, “We help people and society the most when our faculty innovates, and I love figuring out ways to give smart people the opportunity to do impactful work independently. Furthermore, USC is highly supportive of faculty creating and growing research, educational, and clinical programs the way that they think is best.” This, of course, includes Oghalai’s own groundbreaking research on OCT imaging of the human inner ear.