Nerve In Internal Auditory Canal Research Articles

Intratemporal facial nerve neurofibroma: a case report and review of literature

Facial nerve neurofibromas (FNN) are a rare benign tumor of facial nerve can arise from anywhere along the course of the facial nerve from the cerebellopontine angle (CPA) to the extracranial branches within the parotid. They are most commonly located in the parotid gland, and FNN in temporal bone are rarely reported. Intratemporal facial neurofibroma arise from facial nerve in internal auditory canal or in Fallopian canal. It usually manifests as progressive facial palsy, but also can present as sudden or repetitive facial palsy mimicking Bell’s palsy. We reported a case of intratemporal facial neurofibroma arising mainly from mastoid segment in 17-year-old female who presented with progressive facial palsy for 3 years. We briefly reviewed previous cases of intratemporal facial neurofibroma reported in the literature to provide a comprehensive understanding of this rare entity.

The Preoperative Diagnostic Value of MRI and Otoneural Tests in Acoustic Neuroma.

ObjectivesTo determine the preoperative diagnostic accuracy of MRI and otoneural tests (ONT) for acoustic neuroma (AN) in a cohort of unselected patients with pontocerebellar angle tumors. To find a convenient way to screening out the potential asymptomatic AN patient earlier.DesignThis diagnostic accuracy study was performed in a central hospital and included a consecutive sample of unilateral incipient pontocerebellar angle tumor patients referred for MRI and ONT before surgery. Different AN features of MRI and ONT were collected and concluded into preoperative diagnostic variables or variable combinations. Those of MRI and ONT are analyzed and compared with biopsy results by multivariable receiver operating characteristic (ROC) analysis. The early-stage group, the course of which is 1 year or less, was separately computed and compared.ResultsEighty-three subjects were collected from June 2013 to June 2019; 62 were confirmed AN postoperatively by biopsy, whereas others are not AN. The area under the curve (AUC) of MRI was 0.611, whereas the AUC of ONT was 0.708. In the early-stage group, the AUC of MRI was 0.539, and the AUC of ONT was 0.744.ConclusionsONT was able to identify more subjects affected by unilateral incipient AN than MRI preoperatively. Given that ONT is a functional test for internal auditory canal nerves, it is an optimal screening test for AN patients because it provides more information than MRI for the further clinical plan. It is particularly noteworthy for identifying asymptomatic AN patients and for early stage. Therefore, it may help more patients from unnessesary surgery. Furthermore, an MRI follow-up is suggested if the patient was found alert in ONT.

Comparative Study between 3D Balanced Fast Field Echo Sequence and 3D Driven Equilibrium Sequence in the Assessment of the Inner Ear Structure and Internal Auditory Canal Nerves

AbstractBackground: MR cisternography using three dimensional (3D) heavily T2-weighted imaging techniques is considered the main imaging modality for identification and assessment of inner ear structures anatomy and pathology as well as for identification of the posterior fossa cranial nerves, and there are two techniques that are usually used which are fast spin-echo including Driven equilibrium (DRIVE) and fast gradient-echo techniques including Balanced fast field echo (bFFE).Aim of Study: To compare the image quality of 3D DRIVE and 3D bFFE sequences in the assessment of the inner ear structures and internal auditory canal cranial nerves.Material and Methods: 15 patients underwent MR imaging of the temporal bone using both 3D bFFE and 3D DRIVE sequences with a comparison between the two sequences as regards the clarity of cranial nerves and inner ear structures.Results: The 3D bFFE sequence was statistically signifi-cantly better than 3D DRIVE for demonstration of the cochlear, and vestibular nerves, and it was slightly better for visualizing the facial nerve as well as the cochlear inner structure. The 3D DRIVE showed a statically insignificant supremacy over 3D bFFE for visualization of the three semicircular canals and vestibule.Conclusion: The 3D bFFE shows slightly better imaging quality over 3D DRIVE with the advantage of less imaging time.

Determination of the relationship between internal auditory canal nerves and tinnitus based on the findings of brain magnetic resonance imaging

Abstract This experimental study aimed to investigate a relationship between tinnitus and thicknesses of internal auditory canal and nerves in it. It was performed on brain magnetic resonance images of patients who consulted the ear, nose, and throat clinic with tinnitus complaint. Statistical hypothesis tests and classification experiments were performed on these data to find out structural differences in internal auditory channel components in patients with tinnitus after obtaining cross-sectional areas of nerves as thicknesses. Both the hypothesis tests and classification results showed that the thicknesses of nerves in tinnitus cases were different from those in normal cases. In particular, the hypothesis tests for the superior vestibular nerve and internal auditory channel showed the highest significance, indicating the relationship with tinnitus. The classification results indicated the possibility of classification for tinnitus identification, establishing a computer-assisted diagnostic system to help physicians.

長期間にわたり聴力経過を観察可能であったＰａｇｅｔ病症例

We reported a case of Paget's disease presenting fluctuating hearing loss together with repeated dizziness and vertigo attacks. Pure tone audiometry in this patient was performed successively during follow-up periods. She visited our hospital 13 years ago with slight low tone sensorineural hearing loss in her left ear. Sensorineural hearing loss in her right ear and sensorineural and conductive hearing loss in left side deterio-rated. Results of her latest examinations were as follows. Glycerol test was positive and inverted reflex was recorded in her right ear. CT showed severe calcification in skull bone and stenos of bilateral internal auditory canal. Endolymphatic hydrops, compres-sion of VIII nerve in internal auditory canal, damage of cochlear hair cell and changes in middle ear conductive system were possible etiology of hearing loss and vertigo. Oral bisphosphonate is used to prevent deterioration of these symptoms. Evaluation of auditory and vestibular function should be continued.