Cochlear nerve deficiency（CND） is a rare inner ear malformation characterized by a hypoplastic or absent cochlear nerve, resulting in variable hearing loss or total deafness, depending on the quantity of nerve fibers present. About 18% of congenital hearing loss are associated with CND. It is a disease of uncertain cause. The outcome of auditory implant in CND patients varies widely. This article will discuss the related issues of CND.
Humans ; Cochlear Nerve/abnormalities* ; Cochlear Implants ; Child ; Cochlear Implantation/methods* ; Deafness ; Hearing Loss

Objective:To explore the value of high resolution computed tomography（HRCT） combined with Magnetic Resonance Imaging（MRI） in the diagnosis of inner ear malformation. Methods:HRCT and MRI data of 82 patients with inner ear malformations were analyzed retrospectively. HRCT MPR and CPR reconstruction of the inner ear structure, facial nerve canal and oblique sagittal MRI reconstruction of the internal auditory canal were performed. The inner ear malformations were classified, the conditions of facial nerve canal and cochlear nerve were evaluated. The association between inner ear malformation and cochlear nerve dysplasia were analyzed by Chi-square test with continuity correction. Results:Among the 82 patients with inner ear malformations,there were 49 cases of bilateral symmetry, 11 cases of bilateral asymmetry and 22 cases of unilateral inner ear malformations. Respectively, the most prevalent types were IP-Ⅱ（42.96%）, dilatation of atrium aqueduct（18.31%） and malformations of atrium and semicircular canal 19.72%. Out of 50 cases of cochlear malformations,only 3 were isolated cochlear malformations, and the rest were accompanied by other malformations of varying degrees. In the 67 ears examined by MRI, 26（38.81%） had cochlear nerve deficiency（CND）, and the incidence of CND varied with different types of inner ear malformations. Out of 142 ears, 28（19.72%） had abnormalities of the facial nerve canal. Conclusion:HRCT combined with MRI can accurately distinguish the types of inner ear malformation and effectively evaluate the facial nerve canal and cochlear nerve, and further provides the important finger and Guide value for the clinician to formulate the reasonable treatment and the operation plan.
Humans ; Ear, Inner/diagnostic imaging* ; Magnetic Resonance Imaging/methods* ; Retrospective Studies ; Female ; Male ; Tomography, X-Ray Computed/methods* ; Child ; Adolescent ; Adult ; Child, Preschool ; Cochlear Nerve/diagnostic imaging* ; Facial Nerve/abnormalities* ; Cochlea/abnormalities* ; Infant ; Young Adult

OBJECTIVE: To investigate diagnostic value and clinical application of MRI in the children with sensorineural hearing loss (SNHL) before cochlear implantation. METHOD: MRI images of 80 children with the diagnosis of SHNL were retrospectively analyzed in combination with the latest classification of inner ear malformation. RESULT: There were 152 ears of inner ear malformation of 80 cases (160 ears), including 38 ears of cochlear malformation, 33 ears of vestibular malformation, 41 ears of semicircular canal malformation, 37 ears of vestibular aqueduct enlargement, 40 ears of internal auditory canal malformation, and 46 ears of cochlear nerve malformation. CONCLUSION MRI can provide detailed and reliable anatomical information for children with SNHL before cochlear implantation, and help to make the classification diagnosis. Therefore MRI is of great clinical significance for operation plan guidance and prognosis assessment.
Child ; Cochlear Implantation ; Cochlear Nerve ; pathology ; Hearing Loss, Sensorineural ; diagnosis ; pathology ; Humans ; Magnetic Resonance Imaging ; Retrospective Studies ; Semicircular Canals ; pathology ; Temporal Bone ; pathology ; Tomography, X-Ray Computed ; Vestibular Aqueduct ; abnormalities ; pathology

OBJECTIVE: To summarize methods on diagnosis of congenital cochlear nerve canal (CNC) stenosis or atresia and to report results of post-operation such as auditory electrophysiological test and speech test. METHOD: Based on temporal bone HRCT and internal acoustic canal MRI, 27 bilateral congenital CNC stenosis/bony atresia cases were distinguished from 3 700 CI cases. Unilateral cochlear implantations were conducted above 27 cases. Post-operation tests such as auditory nerve response telemetry, EABR test, hearing threshold in sound field and speech recognition test were applied in the cases above. RESULT: Incidence of CNC stenosis/bony atresia was observed at 0.73% (27 in 3700 CI cases). Impedance values were in the normal range accounting for 27 cases. Intro operative auditory nerve response telemetry were conducted accounting for 21 cases while 6 cases which were implanted with Combi40 + were not available for this test. Atypical ART response wave was observed for 14 cases, while no response for 7 cases. EABR test was completed in 27 cases within post-operation during 3 months and atypical EABR was identified in all cases. Hearing threshold in sound field was confirmed at 75 dB which was the average value of 500 Hz,1000 Hz,and 2000 Hz in all 27 cases. Speech recognition test result reached to both 65% (21 cases, simple finals test) and fewer than 10% (21 cases, simple initials test). CONCLUSION By temporal bone HRCT pre-operation, CNC stenosis/bony atresia can be diagnosed. According to both relatively poor auditory and speech test results, further research and discussion are requisite to identify CI indication among the cases above.
Child ; Child, Preschool ; Cochlear Implantation ; Cochlear Nerve ; abnormalities ; Constriction, Pathologic ; Female ; Humans ; Infant ; Male ; Treatment Outcome

OBJECTIVE: By watching the effects of cochlear implants in the children with cochlear nerve defects, to evaluate the relationship and efficiency of HRCT AND MRI in diagnostic for cochlear nerve defects. METHOD: The imaging dates and the post-operative effects of the 10 cochlear nerve defect patients were retrospectively analyzed. RESULT: Three patients with bilateral IAC stenosis by HRCT and cochlear nerve defects by MRI but no other abnormal. Seven other patients showed normal IAC by HRCT including 1 showed type IP- I plus vestibular semi circular canal dysplasia. These 7 patients MRI showed 3 bilateral cochlear nerve absent and 4 bilateral cochlear nerve dysplasia. Ten cases of children after 12-32 month follow-up, 3 patients began speaking simple language, whose MAIS scale, CAP and SIR scores improved. One case just began speaking but pronunciation vague. Four cases had reactions to sounds, and can say monosyllabic words. Two cases without effects (1 CI abolished). Compared with other patients with normal cochlear nerve, the effects of the 10 cases were disappointed. CONCLUSION The effects of cochlear implant for the patients with cochlear nerve defects were poor. The preoperative MRI as sessment including oblique sagittal view for cochlear nerve is necessary. The preoperative communication with the parents telling ineffective result possibility is important.
Child, Preschool ; Cochlear Implantation ; Cochlear Implants ; Cochlear Nerve ; abnormalities ; Female ; Humans ; Infant ; Male ; Retrospective Studies

OBJECTIVE: To investigate the changes and determine the difference of electrode impedance and neural response telemetry ( NRT) value with cochlear implants in children with malformed inner ear and normal inner ear. METHOD: Eighty-eight children with multi-channel cochlear implants participated in this study. Children were divided into malformed inner ear group and normal inner ear group. To test the electrode impedance values and NRT value. RESULT: The changes of electrode impedance showed the similar changing pattern in two groups. There was not different in electrode impedance values between the two groups (P > 0.05). The changes of electrode neural response telemetry values showed the similar changing pattern in two groups. There was significantly different in electrode impedance values between the two groups (P < 0.05). The NRT were going up higher from electrode 22 to electrode 1. CONCLUSION The values vary are different programming sessions and electrodes during the first 3 months of cochlear implant use. To acquire better hearing frequent programming sessions are necessary.
Adolescent ; Case-Control Studies ; Child ; Child, Preschool ; Cochlear Implantation ; Cochlear Implants ; Cochlear Nerve ; Ear, Inner ; abnormalities ; physiopathology ; surgery ; Electric Impedance ; Electrodes ; Female ; Humans ; Infant ; Male

OBJECTIVE: To evaluate the feasibility of cochlear implantation by functional magnetic resonance imaging (fMRI) in a patient with cochleovestibular nerve hypoplasia. METHOD: Audiometry, radiological examination and fMRI of the auditory cortex were performed to a 15-year-old boy with bilateral hearing loss before cochlear implantation. RESULT: Results of pure tone audiometry and auditory brainstem responses showed profound sensorineural hearing loss (SNHL). Transiently evoked otoacoustic emission was absent on both sides. High resolution computed tomography revealed the inner ear malformation (incomplete partition I) on both side. Oblique sagittal reconstruction in magnetic resonance imaging (MRI) showed the malformation of cochleovestibular nerve, fMRI demonstrated the activation of the right primary auditory cortex during 1-kHz monaural stimulation on the left side. No cortical activation appeared during the monaural right acoustic stimulation using the same sound pressure level. The child had subjective auditory response 1 month after cochlear implantation on his left side. CONCLUSION fMRI would be an effective measure in the assessments for the cochlear implantation candidates, combining with audiometry and radiological examination, especially when MRI shows cochleovestibular nerve malformation in these patients.
Adolescent ; Child ; Cochlear Implantation ; methods ; Cochlear Implants ; Evoked Potentials, Auditory, Brain Stem ; Hearing Loss, Sensorineural ; physiopathology ; Humans ; Magnetic Resonance Imaging ; Male ; Vestibulocochlear Nerve ; abnormalities ; physiopathology

PURPOSE: To report a case of bilateral congenital optic disc coloboma associated with the right seventh and eighth cranial nerve palsy. CASE SUMMARY: A female neonate with right facial palsy (seventh cranial nerve palsy) and right earlobe hypoplasia was referred for examination for retinopathy of prematurity (ROP). Bilateral optic disc coloboma and peripapillary choroidal defect was detected on the fundus examination and the anterior segment examination revealed no specific findings. On the otolaryngologic examination, laryngomalacia and floppy epiglottis were observed and left otitis media and mastoiditis were noted on the temporal bone computed tomography (CT). On the auditory brain stem response (ABR), right electro-potential was not detected and right cochlear nerve palsy (eighth cranial nerve palsy) was diagnosed. Further chromosomal analysis and brain magnetic resonance imaging (MRI) revealed no abnormal findings. However, on echocardiography, an atrial septal defect was detected and on upper gastrointestinal series, gastroesophageal reflux disease (GERD) was diagnosed. CONCLUSIONS: Congenital optic disc coloboma is frequently accompanied by other congenital deformities or abnormalities, and therefore, systemic examinations and tests to detect associated findings are required.
Brain ; Choroid ; Cochlear Nerve ; Coloboma ; Congenital Abnormalities ; Cranial Nerve Diseases ; Cranial Nerves ; Echocardiography ; Epiglottis ; Evoked Potentials, Auditory, Brain Stem ; Facial Paralysis ; Female ; Gastroesophageal Reflux ; Heart Septal Defects, Atrial ; Humans ; Infant, Newborn ; Laryngomalacia ; Magnetic Resonance Imaging ; Mastoid ; Mastoiditis ; Otitis Media ; Paralysis ; Retinopathy of Prematurity ; Temporal Bone ; Vestibulocochlear Nerve

OBJECTIVE: To observe normal and abnormal findings of foramina within internal auditory canal (IAC) fundus with Virtual Endoscopy of multisection helical Computed Tomography. METHOD: CT scanning of temporal bone was undergone in 25 volunteers (50 ears) in the normal group, in 8 cases (13 ears) with foramina hypoplasia within IAC fundus which were shown on CT and MRI images. CT virtual endoscopy (CTVE) findings were observed in the normal and abnormal groups. The lower threshold value was 900-1200 HU, the upper value was 3,071 HU in CTVE definitions. RESULT: The shape and position of foramina within IAC fundus were shown on the CTVE image, 50 foramina within IAC fundus were shown in all normal cases. In abnormal group, 9 ears were shown as IAC fundus disorder and foramina absent, only 1 foramina was shown in 1 ear, 2 foramen in 4 ears, 3 foramen in 2 ears, 4 foramen in 2 ears; Abnormal shape of cochlear nerve foramina was seen in 4 ears. Other malformations were also shown, including IAC malformations in 3 ears and inner ear malformations in 8 ears. CONCLUSION CTVE is useful to show the shape and position of normal foramina and pathological changes in the patients with foramina hypoplasia within IAC fundus.
Adolescent ; Adult ; Case-Control Studies ; Child ; Child, Preschool ; Cochlear Nerve ; abnormalities ; diagnostic imaging ; Ear Canal ; abnormalities ; diagnostic imaging ; Ear, Inner ; abnormalities ; diagnostic imaging ; Female ; Hearing Loss, Sensorineural ; congenital ; diagnostic imaging ; Humans ; Male ; Middle Aged ; Tomography, Spiral Computed ; methods ; Young Adult