Keywords: Magnetic Resonance Imaging , Inner Ear , Cochlear , Meniere's Disease , Hearing Loss , Ringing in the ears , Tinnitus , Healthy Volunteers
IRB Number: 00029204
Specialty: Radiology, Radiology
Sub Specialties: Head and Neck Imaging,
The focus of this research is to develop MRI techniques that will allow visualization of the cochlear infrastructure, including the evaluation and analysis of the cochlear fluid spaces, for the purpose of developing an objective test for the diagnosis of endolymphatic hydrops in human subjects. The University of Utah is at a distinct advantage to develop such techniques. In the past the development of a novel surface radiofrequency (RF) coil, a dedicated temporal bone coil consisting of a bilateral two channel surface coil, improved the cochlear images obtained over that of a head coil and another bilateral four channel coil designed for carotid MRA studies. We are also developing and testing a newer RF coil designed specifically for the inner ear. Additionally, our 3T MRI scanner has been modified to allow simultaneous application of a head/neck insert gradient with the standard whole-body gradients. We have demonstrated that application of a dual gradient system can achieve double or triple resolution with no change in imaging parameters. It can also achieve moderate increase in resolution with increased signal to noise ratio (SNR) and reduced image blurring. Finally, we have implemented several novel pulse sequences designed to obtain very high resolution images of the inner ear without the banding artifacts of steady-state sequences. These sequences include options to test for fluid motions that are synchronous with the cardiac cycle. We propose to test these unique RF coils, pulse sequences, and the dual-gradient system in the study of inner ear pathologies, specifically endolymphatic hydrops, sudden sensorineural hearing loss, and cholesteotoma. For imaging a Primary Children’s hospital, we will not use these coils, pulse sequneces or dual-gradient systems. Instead, we will evaluate optimal timing of cochleovestibular enhancement from administration of gadolinium.
The purpose of this research study is to improve MRI techniques that allow for the visualization of pathologies of the inner and middle ear. Although there are currently imaging techniques available to us to see the inner and middle ear structures, our hope is to develop a technique that will allow us to see the very small, fine structures of the inner and middle ear with detail that has never been seen before. Our hope for doing this is that we will one day be able to use combinations of these novel techniques to aid in the diagnosis of disorders of the inner ear, such as Meniere’s disease, sudden sensorineural hearing loss, and tumors of the inner and middle ear. Meniere’s disease is a significant and at times debilitating disease of the inner ear. Patients with this disease have episodes of extreme dizziness, ringing in the ears, and hearing loss. During these episodes patients are often unable to continue their daily activities, including work and care of their families. Progressive hearing loss can occur with successive episodes, resulting at times in complete loss of hearing in the affected ear. Currently there are no objective tests to aid in the diagnosis of Meniere’s disease. Sudden hearing loss can result from other causes that relate to the structure of the inner ear, auditory nerves that carry the signals to the brain, and conditions, such as congenital cytomegalovirus (CMV). Cytomegalovirus (CMV) is the most common congenital viral infection and an important cause of sensorineural hearing loss (SNHL) with an estimated 40,000 newborns infected annually. It is estimated to account for at least one-third of SNHL in young children. It is estimated that it causes more hearing loss in children than did Haemophilus influenzae meningitis in the pre- H. influenzae type b (Hib) vaccine. Tumors can occur in the middle ear. These are generally benign but can damage the delicate bones connecting the ear drum to the cochlea. It is our goal to develop improved MRI techniques which will allow us to visualize the structures of the inner and middle ear so that we will one day be able to better diagnose and treat patients with these debilitating diseases.
Principal Investigator: Dennis Parker
Department: Radiology Research
Phone: (801) 587-8638