The Research Of Inner Ears Disease By Intratympanic Gadolinium Injection Using Three-dimensional Fluid Attenuated (3D-FLAIR) MRI

Objective: Evoke Pure-Tone Audiometry, Electrocochleography, Vestibular Evoked Myogenic Potential(VEMP) and Glycerin test, we investigated the incidence, the diagnostic value and prognostic of endolymphatic hydrops imaging of inner ear diseases such as Meniere’s disease(particularly bilateral Meniere’s disease), idiopathic sudden deafness, delayed endolymphatic hydrops and other inner ear diseases by intratympanic injection of gadolinium based on contrasting agents for the inner ear, using three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging(3 D-FLAIR MRI).Methods: By 3 D-FLAIR MRI after intratympanic injection of gadolinium.From February 2010 to December 2013, at the Otolaryngology Head and Neck Surgery Department at the First Affiliated Hospital of Fujian Medical University, to evaluate inner ear diseases, we collected patients with Meniere’s disease, sudden deafness, delayed endolymphatic hydrops and other types of inner ear disease. Gadolinium hydrate diluted eightfold with saline was used and injected intratympanically using a 23-gauge needle through the tympanic membrane in ears of each patient, After 24 hours, 3D fluid-attenuated inversion recovery MRI was performed using a 3.0-Tesla unit. Imaging methods for EH evaluation by using the Syngo suite, routine hydrography images were processed with three-dimensional, multiplanar reconstruction and maximum intensity projection. Then we introduced a new method with which to diagnose endolymphatic hydrops, using a system to score the MRI appearance of the perilymphatic space. In our clinical studies, we used different grading methods to evaluate EH in those inner-ear diseases just described. Then we summarized, analyzed, and compared the examination results with clinical symptoms, pure tone audiometry, electrocochleogram, vestibular evoked myogenic potential(VEMP) and(or) glycerin test.Results: MRI showed gadolinium was distributed to the perilympha through the round window and made the perilymphatic space enhanced and allowed a distinguishment between the endolymphatic and perilymphatic clearance.Endolymphatic Hydrops(EH) was found out by the enlargement of low signal space and reduction of high signal space. We reported a convenient and effective method with which to diagnose EH, using a system to score the MRI appearance of the perilymphatic space. Basing it on the scores from the different labyrinth components we developed the diagnostic function. Another diagnostic method that was used comprised of the receiver operating characteristic curve analysis of the total MRI scores. The contrast results between the different inner ear diseases had relevance to the related clinical data. After intratympanic injection of gadolinium a 3D-FLAIR MRI helped us to clearly see EH directly and it also showed a higher sensitivity, due to this we are able to use it in investigating the causes and histopathological changes of Meniere’s disease as a tool. Until now, the etiology mechanisms of sudden deafness is unknown. Some authors considered EH is associated with sudden deafness. By utilizing this type of tool, we may know more about sudden deafness to some extent, and realize how drugs distribute within the labyrinth, allowing for effectively utilizing intratympanic injections of drugs as a treatment strategy for sudden deafness. After an intratympanic injection of gadolinium the 3D-FLAIR MRI provided the objective standard for the diagnosis of the disease, also for a treatment plan, evaluating the prognosis of patients. In addition to follow-up, patients without complications such as infection, perforation of tympanic membrane. A further large sample is still needed to assess the risk of this examine.Conclusion: The MRI scoring system we reported has a high level of diagnostic accuracy for EH, and makes it convenient to investigate probable pathogenesis, treatment and prognosis. Imaging by intratympanic gadolinium injection of the inner ear had higher positive rates in patients with interelated diseases compared with pure tone audiometry, electrocochleogram, vestibular evoked myogenic potential(VEMP) and(or) glycerin test. The use of 3D-FLAIR MRI after intratympanic injection of gadolinium–diethylenetriamine pentaacetic acid has a higher value in diagnosis of EH. Although it is an invasive operation with less adverse reactions, it is significant for clinical diagnosis, treatment and prognosis.