Otological IgG4-Related Disease With Inner Ear Involvement: A Case Report and Review of Literature.

Immunoglobulin G4-related disease (IgG4-RD) is a chronic inflammatory disease involving multiple organs. Some studies have reported otological manifestations of IgG4-RD, although most studies describe involvement of the middle ear, and reports on inner ear manifestations are limited. Here, we describe a case of a 30-year-old man with IgG4-RD involving the inner ear. This case demonstrated that IgG4-RD affected the inner ear and caused cochlear ossification. Cochlear implants may be considered for milder cases, and hormone and immunosuppressive therapy may control disease progression.

Neural Response Telemetry Thresholds in Patients with Cochlear Nerve Canal Stenosis.

OBJECTIVE: To explore neural response telemetry (NRT) thresholds in patients with stenotic versus normal cochlear nerve canals. STUDY DESIGN: Case series with chart review. SETTING: Tertiary referral center. SUBJECTS AND METHODS: Thirty pediatric patients with profound sensorineural hearing loss in at least 1 ear and no benefit from amplification underwent computed tomography imaging of the temporal bones. They were divided into 3 groups according to the diameter of the cochlear nerve canal: group A, <1.5 mm; group B, 1.5 to 1.7 mm; group C, 1.8 to 2.1 mm. All patients underwent cochlear implantation with full insertion of all electrodes. NRT was performed both intraoperatively and 6 months postoperatively in all patients; thresholds of electrodes 1, 11, and 22 were compared. RESULTS: Per analysis of variance, intraoperative and 6-month postoperative NRT thresholds were both significantly different among groups A, B, and C at electrodes 1 and 22 but not at electrode 11. On intergroup analysis, group A showed statistically higher thresholds than those of groups B and C; however, no difference was found between groups B and C. CONCLUSION: Cochlear nerve canal stenosis, defined as a canal diameter <1.5 mm, is associated with significantly increased NRT thresholds, which may play a role in postimplant performance.

[The relization of EABR test out of cochlea and the effects of different location of electrode on EABR wave].

OBJECTIVE: To investigate the feasibility of the round window stimulation electrical evoked auditory brainstem response (EABR) test, and optimize the parameters of recording and stimulation electrodes positions. METHOD: Ten healthy Hartley guinea pigs (20 ears) were used for the EABR test. The positive stimulation electrodes were placed into the round window niche, the animals were divided into three group according to the negative electrodes position, group A: the electric field was parallel with the projection of cochlear modiolus on the tympanic membrane, group B: the electric field was perpendicular to modiolus projection toward to the mastoid, group C: the electric field was perpendicular to modiolus projection toward to the zygomatic process. A series of optimized recording and stimulation parameters were uesed to reduce the electrical artifact. RESULT: All the 20 ears were normal in the ABR testing, and EABR waves were stable and well-differentiated in the EABR tests out of cochlea. But EABR waves of group A were more stable and differentiated than those of group B and C. In group A, the threshold of EABR was (0.54 ± 0.11) mA, and latency of wave III was (1.71 ± 0.05) ms when the stimulus intensity was 0.8 mA. In group B, the threshold of EABR was (0.62 ± 0.12) mA, and latency of wave III was (1.77 ± 0.03) ms. In group C, the threshold of EABR was (0.70 ± 0.14) mA, and latency of wave III was (1.86 ± 0.04)ms. The threshold of EABR and latency of wave III were significantly different among the three groups by statistic analysis. CONCLUSION: EABR waves were stable and well-differentiated in the EABR tests out of cochlea. The EABR waves were recorded more stably and differentiated when the stimulating electrode and recording electrode were paralleled with the projection of modiolus on the tympanic membrane.

Cochlear implantation in 21 patients with common cavity malformation.

CONCLUSION: The facial recess approach is preferred in common cavity (CC) malformation with an incomplete basal turn, and the transmastoid single-slit labyrinthotomy approach in classic CC malformation. Patients with CC benefit from cochlear implantation (CI) over time, but the audiological and speech development is poorer than in cases with normal cochleas. OBJECTIVES: To discuss the surgical aspects and performance of CI in 21 patients with CC malformation. METHODS: Twenty-one CC malformations were classified into 2 types: classic CC malformation and CC malformation with an incomplete basal turn. Twenty-one patients without inner ear malformation were set as the control group. Thus, data for 42 patients were analyzed. RESULTS: The facial recess approach was used in 3 patients with CC malformation with an incomplete basal turn, and the transmastoid single-slit labyrinthotomy approach in 18 patients with classic CC malformation. After follow-up for 36 months, the average free-field hearing threshold was higher, and the scores for the CAP, SIR, IT-MAIS, and closed-set/open-set auditory speech perception tests were lower than in the control group (p < 0.05).

[Surgery and electroneurophysiological evaluation for CI case with modiolus ossification].

OBJECTIVE: The purpose of this study is to report surgical skills for CI cases with modiolus ossification and to investigate the relation between post-operational electroneurophysilogical test result and speech recognition result. Further more, we also attempt to confirm indications for CI in this specific population. METHOD: Based on temporal bone HRCT, 7 subjects were identified as modiolus ossification from 101 cases with cochlear ossification. Modiolus ossification is confirmed by CT scan if CT value in modiolus reaches or exceeds 900 HU with the exception of congenital modiolus ossification or modiolus seal off. Electroneurophysiological test was conducted intra- and pos-operationally speech tests were applied for 7 subjects. RESULT: Normal impedance value was observed by intro-operational measurement in 7 subjects. EABR test was conducted and negtive response was observed in only 1 subject, while other 6 subjects were confirmed with atypical EABR waves which were observed in apical and middle turn region. Hearing threshold test (in sound field) was applied, no auditory response was recorded for the subject without EABR waveform, while hearing threshold in average for the other 6 subjects was 75 dB. Results of speech tests (Mandarin) were followed as 0 for the one without EABR wave, while 100% (simple finals test) and 30% (simple initials test) for the other 6 subjects. CONCLUSION: Optimal multichannel CI surgery that inserting and locating electrode array spirally is very frequently interrupted by ossification,which was indentified with atypical EABR wave and relative poor speech recognition results, especially in modiolus ossification case. A post-operative negative EABR response may indicate surgical failure following cochlear implantation.

[Morphologic feature and cochlear implant surgical approach for cochlear modiolus deficiency].

OBJECTIVE: To review the classification of cochlear modiolus deficiency and decision on surgical approach for above case,in order to provide mastery for cochlear implant (CI) indication. METHOD: Basing on temporal bone HRCT pre-operation, CI subjects with modiolus deficiency were defined as following groups: (1) deficiency caused by cochlear dysplasia (Mondini malformation); (2) deficiency caused by dysplasia of cochlear and vestibule (Common cavity malformation); (3) deficiency caused by absence of internal acoustic meatus fundus (IP-III malformation). Three types of surgical approach were utilized: type I, electrode array was introduced through facial recess, enlarged the round window, type II, opened the surface of chchlea, electrode array was introduced through facial recess, fenestration on posterior promontory and then inserted around lateral wall of inner-cochlear cavity. type III, electrode array was introduce through fenestration of lateral semicircular canal and then placed close to the bony wall of common cavity. RESULT: One hundred and sixty-six cochlear modiolus deficiency cases were identified into 3 groups as following: 135 Mondini malformation cases into group a, 18 common cavity malformation cases into group b, and 13 IP-III malformation cases into group c. Surgical approach: type I were used in 136 cases (123 Mondini cases and 13 IP-III cases), while approach type II in 12 cases (12 Mondini cases), and approach type III in 18 cases (18 common cavity cases). Income post-operation of CI: For group a (Mondini malformation), post-activation mean hearing threshold in sound field was 65 dB, speech recognition score is 95% (single finals test) and 25% (signal initials test), while it was 80 dB, 60% and 0 for group b (Conmon cavity malformation), and it was 55 dB, 100% and 45% for group c (IP-III malformation). CONCLUSION: The income of speech recognition score for cochlear modiolus deficiency was relatively poor, group b was worst and group c was best, while group a moderate.

Surgical methods and postoperative results of cochlear implantation in 79 cases of ossified cochlea.

CONCLUSION: A man-made bone tunnel of 1.5 turns around the modiolus can be created in cases of total cochlear ossification. Patients with ossified cochlea types I and II achieved satisfactory hearing results after cochlear implantation (CI). Patients with ossified cochlea type III, in which the modiolus is damaged by the ossification, showed poor hearing results after CI. OBJECTIVES: To introduce a new CI surgical technique for ossified cochlea and to summarize postoperative hearing results. METHODS: A total of 79 patients with ossified cochlea who underwent CI were analyzed. Cases were divided into three types: type I, round window ossification; type II, partial cochlear ossification; and type III, complete cochlear ossification. Four surgical methods were used: method A, applicable to type I; methods B and C, applicable to type II; and method D, applicable to type III. Sound field audiometric and speech tests were performed 6 months postoperatively. RESULTS: All surgeries were successful. The average hearing thresholds for warble tone were 35 dB hearing level (HL) in types I and II and 75 dB HL in type III. The average recognition rates of Mandarin speech were 100% (single finals) and 91% (single initials) in types I and II and 20% (single finals) and 0% (single initials) in type III.

[Diagnosis of cochlear nerve foramen stenosis and atresia of the cochlear implantation].

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.

Electrically-evoked frequency-following response (EFFR) in the auditory brainstem of guinea pigs.

It is still a difficult clinical issue to decide whether a patient is a suitable candidate for a cochlear implant and to plan postoperative rehabilitation, especially for some special cases, such as auditory neuropathy. A partial solution to these problems is to preoperatively evaluate the functional integrity of the auditory neural pathways. For evaluating the strength of phase-locking of auditory neurons, which was not reflected in previous methods using electrically evoked auditory brainstem response (EABR), a new method for recording phase-locking related auditory responses to electrical stimulation, called the electrically evoked frequency-following response (EFFR), was developed and evaluated using guinea pigs. The main objective was to assess feasibility of the method by testing whether the recorded signals reflected auditory neural responses or artifacts. The results showed the following: 1) the recorded signals were evoked by neuron responses rather than by artifact; 2) responses evoked by periodic signals were significantly higher than those evoked by the white noise; 3) the latency of the responses fell in the expected range; 4) the responses decreased significantly after death of the guinea pigs; and 5) the responses decreased significantly when the animal was replaced by an electrical resistance. All of these results suggest the method was valid. Recording obtained using complex tones with a missing fundamental component and using pure tones with various frequencies were consistent with those obtained using acoustic stimulation in previous studies.

[Development of electrically evoked auditory brainstem response modules of REZ-I domestic cochlear implant device].

OBJECTIVE: To develop electrically evoked auditory brainstem response(EABR) modules of REZ-I domestic cochlear implant device, and testify the reliability and validity of the modules. METHODS: Postoperative EABR were recorded in guinea pigs by using the self-designed EABR module. RESULTS: EABR waves were recorded in all 15 ears of 9 guinea pigs with normal hearing. The threshold was (159.00 ± 50.21) current level (CL) and eIII wave latency was (2.36 ± 0.46) ms of 100 µs pulse width stimulation; for 150 µs pulse width stimulation, the threshold was (131.44 ± 49.25) CL and eIII wave latency was (2.59 ± 0.46)ms; for 200 µs pulse width stimulation, the threshold was (119.63 ± 52.56) CL and e III wave latency was (2.62 ± 0.44)ms. CONCLUSION: According the preliminary results of the study, the reliability and stability of the EABR modules of domestic cochlear implant device can meet the demands of EABR recording.

Cochlear implantation surgery in patients with narrow facial recess.

CONCLUSION: The new method of facial recess enlargement through suspending, antedisplacing, and adhering the chorda tympani nerve to the posterior wall of the auditory canal can expose the round window, make electrode insertion easier, and preserve the function of the facial nerve and chorda tympani nerve. OBJECTIVE: To describe and report cochlear implantation surgery in patients with narrow facial recess, including surgical technique and postoperative outcomes. METHODS: Cochlear implantation surgery was performed in our hospital in 39 cases with narrow facial recess by enlarging the facial recess. To enlarge the distance between the facial nerve and chorda tympani nerve, the chorda tympani nerve was suspended. The chorda tympani was anteplaced and adhered to the posterior wall of the auditory canal. RESULTS: Among the 39 cases, the narrowest distance between the facial nerve and the chorda tympani nerve was less than 1.0 mm. All patients successfully underwent cochlear implantation surgery. No injuries of the facial nerve, chorda tympani nerve, or the posterior wall of the auditory canal were reported in any of the patients. There were significant differences in the injuries of the facial nerve, chorda tympani nerve, and posterior wall of the auditory canal in these cases compared with previous approaches to this operation.

[Surgical approach of cochlear implantation in patients with common cavity].

OBJECTIVE: To discuss the surgical approach of cochlear implantation in patients with common cavity. METHOD: Seventeen patients with common cavity underwent cochlear implantations through facial recess approach or transmastoid lateral semicircular canal approach,according to the preoperative imaging and audiological evaluation. RESULT: Common cavity was opened and electrodes were inserted smoothly in all cases. Facial recess approach was used in 3 patients, while transmastoid lateral semicircular canal approach was used in the others. Intraoperative "gush" occurred in 4 cases. None of the cases developed intraoperative or postoperative complications, such as facial paralysis, meningitis and cerebrospinal fluid leakage. All cases had improvements in hearing. Atypical postoperative EABR responses were detected, the average free filed hearing threshold was 65 dB HL, the average speech recognition score of Chinese vowels was 75%, and the average speech recognition score of Chinese consonant was less than 10%. CONCLUSION: (1) Selection of surgical approach for patients with common cavity: if the basal turn of cochlear could be distinguished at the posterior tympanum side of common cavity, the facial recess approach was used; if the cochlear,vestibule and the lateral semicircular canal merged to be a spherical cavity, the transmastoid lateral semicircular canal approach was used. (2) Surgical approach of cochlear implantation affected the postoperative outcomes. (3) Outcomes of cochlear implantation in common cavity patients were much poorer than normal cochlear cases.

[Canal-wall-down mastoidectomy and tympanoplasty surgery preserving chorda tympani nerve integrality].

OBJECTIVE: To report the way for searching the chorda tympani nerve and the significance for preserving the chorda tympani nerve during canal-wall-down mastoidectomy and tympanoplasty surgery. METHOD: Sixty-six cases with chronic suppurative otitis media underwent canal-wall-down mastoidectomy and tympanoplasty surgery. According to the marker of the short crus of incus, the posterior wall of auditory canal was lowered and crista of the chorda tympani nerve was found through tracing the facial nerve contour. The chorda tympani nerve was preserved after clearing the surrounding tissue. RESULT: Among the 66 cases, 24 cases had middle ear cholesteatoma, 42 cases had granulation in middle ear. The cholesteatoma and granulation on the surface of the chorda tympani nerve were cleared thoroughly. No neurotmesis or obvious change of taste occurred after operation. CONCLUSION: Canal-wall-down mastoidectomy and tympanoplasty surgery preserving chorda tympani nerve integrality may preserve the structure and function of the chorda tympani nerve, reduce the risk of ossicle extrusion above the head of stapes and serve as a frame for transplanting fascia.

[Perioperative complications of 1396 patients with cochlear implantation].

OBJECTIVE: To discuss the perioperative complications of 1396 cases (1402 ears) with cochlear implantation (CI), and to supply clinical experience for risk reduction in the perioperative period. METHOD: All patients were profound sensorineural deafness, with 1379 prelingual cases and 17 postlingual cases. (1) Preoperative examinations: audiology,imaging studies, evaluation of physical and intellectual development. (2) Perioperative complications. RESULT: (1) Perioperative complications: transitory postoperative facial palsy in 4 cases; external auditory canal and membrana tympani injury in 14 cases; gusher in 91 cases; cerebral dura mater injury in 2 cases; problems of electrodes in 31 cases including 2 of electrodes inserted into inner auditory canal and 1 into scala vestibuli, 28 of electrodes squire in the cochlea; transient vertigo in 231 cases; scalp hematoma in 39 cases. (2) Systematic postoperative complications: fever ( >38 degrees C) in 21 cases; acute gastritis in 27 cases; bronchitis and pneumonia in 5 cases; laryngotracheitis in 9 cases. (3) Other complications: artificial cochlear exchange due to computer trouble during operation. CONCLUSION: (1) CI is a relatively safe surgical procedure, but risks still persist during perioperative period including postoperative meningitis, facial nerve and chorda tympani nerve injury,and so on. (2) To ensure successful operation, perioperative managements should be standardized.

Cochlear implantation in China: review of 1,237 cases with an emphasis on complications.

OBJECTIVE: The purpose of this study is to retrospectively review the complications of patients who underwent cochlear implantation at 51 hospitals in mainland China over a decade. METHODS: A retrospective analysis of 1,237 patients who underwent cochlear implantation from February 1998 to December 2008. The patients were reviewed for demographic information, type of hearing loss, abnormal findings on temporal CT scans, cochlear implant device, procedure time, and complications that included meningitis, hematoma (intracranial and extracranial), wound infection and implant extrusion, cerebrospinal fluid leak and facial palsy. RESULTS: A total of 1,237 patient records were identified, and pertinent clinical information was reviewed. Of the patients, 59.6% were male, and 98.9% were prelingually deaf. The most common etiologies of hearing loss were: ototoxicity (28.1%), non-syndromic congenital hearing loss (14.8%), and inner ear malformation (18.5%). Inner ear malformations included: enlarged vestibular aqueduct (9.4%), Mondini defect (5.4%), common cavity (2.8%), cochlear ossification (3.9%), round window dysplasia (0.4%), and narrow internal auditory meatus (1.2%). The most common intraoperative complications were: gusher (5%) and electrode kinking (2.3%). The most common postoperative complications were hematoma (1.7%), wound infection and implant extrusion (0.5%), and device failure (0.9%). No CSF leakage or permanent facial palsy occurred. CONCLUSIONS: Cochlear implantation is a safe and reliable otosurgical procedure in China, and the rate of complications is similar to developed countries. Carefully preoperative preparation and standardization of the procedure are important for the development of cochlear implant programs in developing countries.

[Cochlear implantation in patients with secretory otitis media].

OBJECTIVE: To evaluate the indications and surgery time of cochlear implantation in patients with otitis media with effusion (OME). METHODS: Cochlear implantation was performed in 26 patients with bilateral profound sensorineural hearing loss and OME. Non-Surgical Treatment was conducted for OME before the following implantation. According to the standards of the indications and surgery time, surgery was carried out. During the process of surgery operation, related lesions of OME were completely removed and proper drainage was then constructed. After the surgery, the patients were regularly followed up, and the effective of cochlear implantation was evaluated. RESULTS: Unilateral ear of 26 patients was successfully operated. Among them, 5 cases were left ears and the remaining was right ears. All implant devices worked normally after 1 month. Had been followed up from 13 months to 4.3 years, 19 patients with OME were healed and the remaining was turning better. No evidence showed phenomenon of the eardrum perforation and acute attack of OME. CONCLUSIONS: Once the indications of cochlear implantation in patients with OME are guaranteed, the surgery should be conducted as early as possible. The complications of cochlear implantation in patients with OME can be effectively avoided through proper treatment in different stages.

Application of intraoperative round window electrocochleography for screening the patients with auditory neuropathy.

BACKGROUND: Most patients with auditory neuropathy (AN) could receive good even the best effects after cochlear implantation. How to diagnose AN objectively and accurately is very important. In this study, we screened the patients with AN according to the presence or absence of compound action potential (CAP) of intraoperative round window electrocochleography (RW ECochG). METHODS: Intraoperative RW ECochG was performed on 32 patients with profound sensorineural deafness, who had normal cochlea during cochlear implantation surgery under general anesthesia in the standard operating room. The cochlear microphonic (CM) and CAP of RW ECochG was observed and recorded. RESULTS: The presence of CM but the absence of CAP of RW ECochG occurred in 12 among the 32 patients. They were suspected to suffer from AN. The rest patients who had CM and CAP of RW ECochG were thought not to suffer from AN. CONCLUSION: Application of intraoperative RW ECochG during the cochlear implantation surgery may objectively and accurately screen the patients with AN, and can give a meaningful clue for implanted device working.