New Imaging Tool Measures Inner Ear Fluid To Assess Hearing Loss

Optical coherence tomography (OCT), a instrumentality routinely utilized to diagnose and scheme curen for oculus diseases, has now been modified to cod images of nan soul ear. A proof-of-concept study led by researchers astatine nan Keck School of Medicine of USC recovered that OCT imaging tin measurement fluid levels successful nan soul ear, which correlate pinch a patient's grade of proceeding loss. The findings were conscionable published successful Science Translational Medicine.

These findings are breathtaking because proceeding nonaccomplishment tin hap very suddenly, and we often don't cognize why. OCT offers a measurement to research nan underlying origin and perchance guideline treatment."

John Oghalai, MD, elder author, professor and chair successful nan Caruso Department of Otolaryngology – Head and Neck Surgery and nan Leon J. Tiber and David S. Alpert Chair successful Medicine astatine nan Keck School of Medicine

A abrupt nonaccomplishment of hearing, sometimes accompanied by vertigo, happens successful Ménière's disease, cochlear hydrops and different receptor conditions. One hallmark of these diseases is an imbalance of fluids successful nan soul ear, but measuring fluid equilibrium is simply a challenge. The champion disposable technology, magnetic resonance imaging (MRI), lacks nan solution needed to reliably diagnose aliases guideline treatment.

OCT offers a quicker, much meticulous and little costly measurement to spot soul receptor fluids, hairsbreadth cells and different structures applicable to diagnosing and treating proceeding loss. With backing from USC and nan National Institutes of Health, Oghalai, Brian Applegate, PhD, professor of otolaryngology – caput and cervix surgery, and ophthalmology astatine nan aesculapian schoolhouse and of biomedical engineering and electrical and machine engineering astatine USC Viterbi School of Engineering, and their squad tested nan caller instrumentality successful 19 patients undergoing receptor room for various conditions. They recovered that OCT could reliably observe fluid imbalance successful nan soul ear, which was correlated pinch nan severity of a patient's proceeding loss. Although nan instrumentality is presently constricted to usage during surgery, nan researchers are moving to accommodate it for exertion successful nan clinic.

The latest findings build connected nan team's earlier work, wherever they utilized OCT to cod images of nan cochlea successful awake animals for nan first time. With improvements, nan instrumentality could thief clinicians much quickly find nan origin of proceeding loss, find really to dainty it, and moreover support efforts to create caller therapies to reconstruct hearing, Oghalai said.

Measuring fluid balance

OCT uses ray waves to scan insubstantial and create 3D images, akin to nan measurement ultrasound produces images utilizing sound waves.

The Keck School of Medicine squad utilized nan instrumentality to scan nan soul ears of 19 patients undergoing receptor surgery. Six patients had normal soul receptor function, 4 had Ménière's disease, and 9 had vestibular schwannoma (a benign tumor connected a nervus that connects nan soul receptor to nan brain). During surgery, a heavy outer bony known arsenic nan mastoid was temporarily removed, allowing researchers to usage OCT to cod images of nan fluid compartments successful nan soul ear.

OCT images showed that patients pinch Ménière's illness or vestibular schwannoma had higher levels of a fluid called endolymph, compared to those pinch normal soul receptor function. Increased endolymph levels were linked to greater proceeding loss, indicating that measuring these fluid levels could thief foretell nan severity of symptoms.

"We've known for a agelong clip that endolymph is related to proceeding loss, but until now, measuring it successful a surviving diligent has been a awesome challenge," Oghalai said.

A faster measurement to help

OCT tin assistance surgeons, including by helping to debar harm to delicate receptor structures and distinguishing encephalon tumors from patient tissue. To this end, nan researchers are moving to create a smaller, much affordable type of nan instrumentality that they scheme to administer and trial pinch surgeons.

But OCT tin use galore much group if it tin beryllium utilized to cod images of nan soul receptor while patients are awake successful nan clinic. To execute this goal, Oghalai, Applegate and their squad person received national backing and a Nemirovsky Engineering and Medicine Opportunity (NEMO) Prize from USC. They are now moving to amended nan package and image-processing techniques to get clear images from patients without removing nan mastoid bone.

OCT could connection awesome benefits complete MRI because it is little expensive, faster and tin beryllium done back-to-back to trial curen effectiveness. For example, a supplier could cod an image, springiness medicine curen for a fluid imbalance, past return different image 30 minutes later.

"Patient symptoms-sensations of proceeding loss, unit successful nan ear, aliases vertigo-can beryllium affected by galore unrelated factors specified arsenic mood, stress, nasal congestion and allergies. However, soul receptor fluid levels reliably measure what is going connected wrong nan soul ear," Oghalai said. "We person tons of curen options available, but it often takes galore weeks to fig retired what useful for a fixed patient. This could beryllium a faster measurement to help."

If OCT tin beryllium utilized extracurricular nan operating room, it tin besides support nan improvement of caller treatments for proceeding loss. Several cistron therapies, which purpose to regenerate mislaid hairsbreadth cells successful nan soul ear, are presently successful objective trials. OCT whitethorn supply a accelerated and precise measurement to trial nan effectiveness of specified therapies by collecting images of hairsbreadth cells arsenic they grow.

"OCT helped researchers create treatments for retinal diseases, including macular degeneration, truthful we're hoping it tin person a akin effect for proceeding loss," Oghalai said.

About this research

In summation to Oghalai and Applegate, nan study's different authors are Wihan Kim, Dorothy W. Pan, Bong Jik Kim, Zihan Yang, Marcela Moran Mojica, Joni K. Doherty and Seiji B. Shibata from nan Caruso Department of Otolaryngology - Head and Neck Surgery, Keck School of Medicine of USC, University of Southern California.

This activity was supported by nan National Institute connected Deafness and Other Communication Disorders of nan National Institutes of Health [R01DC022232, R25DC019700]; nan National Institute of Biomedical Imaging and Bioengineering of nan National Institutes of Health [R01EB027113]; and University of Southern California Nemirovsky Engineering and Medicine Opportunity (NEMO) Prize.