Cochlear Implant Surgery Through Round Window Approach Is Always Possible.

OBJECTIVES: The benefit of round window (RW) approach for cochlear implant (CI) has been well studied. Because the RW represents a natural door to scala tympani, it facilitates precise electrode insertion. Atraumatic electrode insertion can also be performed without drilling the cochlear lateral wall. However, the RW approach has several limitations. The purpose of this study is to describe successful CI surgeries utilizing the RW approach except for severe cases of temporal bone anomaly. The authors' successful surgical solution for cases involving difficult RW access is also described. MATERIALS AND METHODS: We retrospectively analyzed 377 consecutive surgeries of cochlear implantation performed between June 2010 and December 2018 by a single experienced surgeon. Standard and alternative procedures were used according to anatomical variations. Standard procedures included modified techniques of mastoidectomy in the RW approach, opening of facial recess, exposure of RW membrane, and electrode insertion. Difficult cases involving severe rotated cochlea or hypoplastic mastoid were successfully treated with RW insertion using alternative procedures such as external auditory canal (EAC) wall mobilization and endomeatal approach. RESULTS: We performed CI surgery through a reproducible RW technique in two cases involving endomeatal approach and three cases of EAC mobilization. Other cases were treated using the standard procedure. CONCLUSION: Cochlear implant surgery through RW is reliable, safe, and effective. The RW technique is reproducible via several surgical procedures in most CI cases. Identification and safe exposure of RW membrane is a prerequisite for successful electrode insertion in cochlear implant surgery.

Optimizing maps for electric acoustic stimulation users.

OBJECTIVES: To optimize patient's maps in Electric Acoustic Stimulation (EAS) users based on the degree of post-operative aided hearing thresholds. METHODS: Twenty-one adult EAS patients participated in this study. Patients were subdivided into three groups, based on their unaided hearing threshold: (1) electric complementary (EC, n = 6) patients with ≤30 dB HL at 125-500 Hz with severe to profound hearing loss at higher frequencies who only use electric stimulation, (2) EAS (n = 8) patients with 30-70 dB HL from 125 to 250 Hz and profound hearing loss in high frequencies who use combined EAS, and (3) Marginal-EAS (M-EAS, n = 7) patients with 70-95 dB HL at frequencies ≤250 Hz who use combined EAS. Sentence perception in noise, melodic contour identification, and subjective preference were measured using Full Overlap, Narrow Overlap, Gap, and Meet maps. RESULT: Of the 21 patients that participated, 12 subjects were classified as complete hearing preservation and 9 subjects were classified as partial hearing preservation. The highest performing maps in sentence-in-noise perception and melodic contour identification were Gap, Meet, and Full Overlap for the EC, EAS, and the M-EAS groups, respectively. These results are consistently across different test materials and align with subject preference as well. CONCLUSION: These results suggest that clinical fitting in EAS listening should be individually tailored. EAS performance can be enhanced by optimizing maps between acoustic and electric stimulation based on the degree of aided hearing thresholds.

Bimodal benefit depends on the performance difference between a cochlear implant and a hearing aid.

Objectives The present study characterizes the relationship between bimodal benefit and hearing aid (HA) performance, cochlear implant (CI) performance, and the difference in the performances of the two devices. Methods Fourteen adult bimodal listeners participated in the study. Consonant, vowel, and sentence recognition were measured in quiet and noise (at a +5 and +10 dB signal-to-noise ratio (SNR)) with an HA alone, a CI alone, and with the combined use of an HA and CI in each listener. Speech and noise were presented directly in front of the listener. Results The correlation analyses showed that bimodal benefit was significantly associated with the difference in performances of a CI and an HA in all testing materials, with HA-alone performance in vowel recognition, and with CI-alone performance in sentence recognition. However, regression analyses showed that the independent contribution of the difference in performance across ears to bimodal benefit was significant, irrespective of the testing material or the SNR: the smaller the difference, the greater the benefit. Further, the independent contributions of HA-only performance and CI-alone performance were not significant factors in predicting the existence of bimodal benefit across testing materials and SNRs when the effect of the difference between CI and HA performance was removed from the model. Conclusion The results suggest that bimodal benefit is limited by how effectively the modalities integrate, rather than HA-only or CI-alone performance, and that this integration is facilitated when the performances of the modalities are similar.

Binaural benefit with and without a bilateral spectral mismatch in acoustic simulations of cochlear implant processing.

OBJECTIVES: This study investigated whether a spectral mismatch across ears influences the benefit of redundancy, squelch, and head shadow differently in speech perception using acoustic simulation of bilateral cochlear implant (CI) processing. DESIGN: Ten normal-hearing subjects participated in the study, and acoustic simulations of CIs were used to test these subjects. Sentence recognition, presented unilaterally and bilaterally, was measured at +5 dB and +10 dB signal-to-noise ratios (SNRs) with bilaterally matched and mismatched conditions. Unilateral and bilateral CIs were simulated using 8-channel sine wave vocoders. Binaural spectral mismatch was introduced by changing the relative simulated insertion depths across ears. Subjects were tested while listening with headphones; head-related transfer functions were applied before the vocoder processing to preserve natural interaural level and time differences. RESULTS: For both SNRs, greater and more consistent binaural benefit of squelch and redundancy occurred for the matched condition whereas binaural interference of squelch and redundancy occurred for the mismatched condition. However, significant binaural benefit of head shadow existed irrespective of spectral mismatches and SNRs. CONCLUSIONS: The results suggest that bilateral spectral mismatch may have a negative impact on the binaural benefit of squelch and redundancy for bilateral CI users. The results also suggest that clinical mapping should be carefully administrated for bilateral CI users to minimize the difference in spectral patterns between the two CIs.

Clinical selection criteria for a second cochlear implant for bimodal listeners.

OBJECTIVE: To compare the speech perception benefit, provided by a contralateral hearing aid (HA) or a second cochlear implant (CI). STUDY DESIGN: Repeated measures. PATIENTS: A total of 25 adult subjects participated in the study, including 12 bilateral (10 female and 2 male patients) and 13 bimodal (6 female and 7 male subjects) users. All bilateral users were sequentially implanted. The bimodal users were separated into a poor group (n = 5, aided pure-tone average (PTA) of 55 dB HL or greater at audiometric frequencies of 1 kHz or lesser) and a good group (n = 8, aided PTA < 55 dB HL). MAIN OUTCOME MEASURES: Consonant, vowel, and sentence recognition was measured in quiet and noise at +5 dB and +10 dB signal-to-noise ratios (SNRs). Speech recognition performance was evaluated under three listening conditions: CI alone, HA alone, and CI+HA for bimodal users; first CI alone, second CI alone, and first CI + second CI for bilateral users when speech and noise were presented from the front. RESULTS: There was no significant difference in the binaural benefit between the good bimodal and bilateral groups in vowel and sentence recognition. However, the binaural benefit is significantly better in the bilateral group than in the poor bimodal group for all 3 speech measures. CONCLUSION: These results suggest that the aided pure-tone average at audiometric frequencies of 1 kHz or lesser may serve as one of the clinical criteria for the recommendation of whether bimodal patients should consider a second cochlear implant to maximize their binaural listening ability.

Intralabyrinthine schwannoma involving the cochlea, vestibule, and internal auditory canal: 'canalolabyrinthine schwannoma'.

Intralabyrinthine schwannomas (ILSs) are very rare and most of them involve cochlea-vestibule, internal auditory canal (IAC)-cochlea, or IAC-vestibule areas. However, there is no study reporting on schwannomas involving simultaneously the vestibule, cochlea, and IAC. We report a case of schwannoma involving simultaneously the vestibule, cochlea, and IAC, with the discussion of its possible origin and propose one more new classification, the 'canalolabyrinthine schwannoma', among the ILSs.

Cochlear implantation and connexin expression in the child with keratitis-ichthyosis-deafness syndrome.

We report one child with keratitis-ichthyosis-deafness (KID) syndrome. The child showed sparse, short scalp and body hairs, ichthyotic skin, bilateral sensorineural hearing loss, and visual loss. These are associated with a nucleotide substitution, 148G>A, which results in amino acid change in codon 50 of gap junctional protein connexin (Cx) 26. Immunohistochemistry of skins showed up-regulation of Cx26 and down-regulation of Cx43. He has benefited from cochlear implantation for hearing even though low visual function and skin problems with high risk of infections. This is the very rare report about Cx expression in skins and cochlear implantation in KID syndrome.

Management for the children with otitis media with effusion in the tertiary hospital.

OBJECTIVES: Recently, new evidence-based recommendations have been introduced for diagnosing and managing otitis media with effusion (OME) in children. However, there are some difficulties to follow the general guidelines in the tertiary hospitals. The purpose is to evaluate the efficiency of antibiotics or antihistamines for treatment of children with OME in the tertiary hospital with a randomized prospective clinical study. METHODS: Eighty-four children with OME who had been diagnosed in the tertiary hospital were randomized to receive 5 different medications for 2 weeks. We prescribed antibiotics (amoxicillin-clavulanate syrup) in Group I (n=16), antibiotics/steroids (prednisolone) in Group II (n=18), antibiotics/antihistamines (ebastine) in Group III (n=15), antibiotics/steroids/antihistamines in Group IV (n=17), and mucolytics (ivy leaf extract) in Group V (n=17) for control. We followed-up children every 2 weeks and evaluated the state of OME at 3 months. RESULTS: Thirty six (42.9%) of 84 children were resolved within average 6.9 weeks after the treatments. Thirty-six (42.9%) were treated with ventilation tube insertion and 12 patients (14.3%) were observed. There was no difference in the resolution rates of OME among the five different protocols (P>0.05). There was no difference in the resolution rates among groups who used steroids, antihistamines, steroids and antihistamines, or other medications to manage 42 children with allergies (P>0.05). CONCLUSION: In the tertiary hospital, the cure rate of children with OME was not as high as well-known, and antibiotics or anti-allergic medications were not more effective than control. We may, therefore, need any other guidelines which are different from the previous evidence-based recommendations, including early operation in the tertiary hospitals.

Cystic lymphangioma: trauma may be a significant cause?

Cystic lymphangioma is a rare congenital anomaly of the lymphatic system. Its embryopathogenesis is still controversial. Most lesions present in infancy or early childhood with a swelling found in the head and neck region. We report the case of a woman who presented with a cystic swelling in the left supraclavicular region that appeared after left side thyroidectomy. Surgical excision achieved complete removal. Histology showed the lesion to be a cystic lymphangioma. It can be hypothesized that an embryogenetic origin of the adult lymphangioma is associated with some precipitating trauma such as surgery.

Conductive deafness with normal eardrum: absence of the long process of the incus.

CONCLUSIONS: The most likely cause of lesions with an absence of the long process of the incus was congenital origin because many cases were associated with the stapedial anomaly. However, the possibility of a potential inflammation of this lesion could not be completely excluded, especially in cases with only an absence of the long process of the incus. OBJECTIVE: To clarify whether the absence of the long process of the incus is caused by congenital anomaly or a potential inflammation. SUBJECTS AND METHODS: A total of 21 patients (5 bilateral cases, 16 unilateral cases) with absence of the long process of the incus were reviewed. Operative and histopathological findings of the removed incus were analyzed. RESULTS: The 21 cases with absence of the long process of the incus were classified into 6 types. Thirteen cases showed the absence of the long process associated with the stapedial anomaly, which were all unilateral. Eight cases showed no association with the stapedial anomaly, among which five cases were bilateral. Three of eight cases not associated with the stapedial anomaly showed evidence of resorption in the incus body such as fibrosis and Haversian canal widening.

Bilateral versus unilateral sudden sensorineural hearing loss.

OBJECTIVES: To analyze the clinical characteristics and treatment results between bilateral (bi-) and unilateral (uni-) sudden sensorineural hearing loss (SSNHL). STUDY DESIGN AND SETTING: A retrospective study. METHODS: Three hundred twenty-four patients with SSNHL were classified into two groups; simultaneous bi-SSNHL (n = 16) and uni-SSNHL (n = 308). We compared clinical characteristics, medical history, hearing level, and treatment results between the 2 groups. RESULTS: The incidence of bi-SSNHL was 4.9 percent of overall patients with SSNHL. Bi-SSNHL occurs more commonly in patients of older age, with preexisting diabetes mellitus, and lipid panel abnormalities compared with uni-SSNHL. Ten patients (62.5%) in the bi-SSNHL group showed hearing recovery in 1 or both ears compared with 56.5 percent of patients with uni-SSNHL. Only 12 (37.5%) of all 32 ears recovered in bi-SSNHL, which was significantly lower than in uni-SSNHL. CONCLUSION: Bi-SSNHL has a very low incidence and lower recovery rate than uni-SSNHL. Recognition of similarities and differences between bilateral and unilateral SSNHL can help in counseling and managing the patients.

Systematic facial nerve monitoring in middle ear and mastoid surgeries: "surgical dehiscence" and "electrical dehiscence".

OBJECTIVES: To evaluate and systemize intraoperative facial nerve monitoring (IOFNM) in middle ear and mastoid surgeries. STUDY DESIGN AND SETTING: A prospective study. METHODS: IOFNM was performed in 100 patients undergoing middle ear and mastoid surgeries. We checked "surgical dehiscence" under microscopes, and also estimated the minimal threshold of electric current needed to change the electromyography of facial muscles using Nerve Integrity Monitor (NIM)-2 (Xomed, Minneapolis, MN, USA). RESULTS: Forty-three percent of cases showed "surgical dehiscence" and responded to electric stimulation of 0.7 mA or less. "Electrical dehiscence" (

Audio-vestibular disturbance in patients with Behçet's disease.

OBJECTIVE: The present study prospectively investigated the frequencies and characteristics of audio-vestibular disturbance and the results of audiologic and vestibular function tests in patients with Behçet's disease. STUDY DESIGN: A prospective study. METHODS: Seventeen patients with Behçet's disease (mean age 41.2 [30-56] years, 5 males and 12 females), as well as age- and sex-matched healthy controls, were included in this study. All subjects satisfied the diagnostic criteria of the International Study Group for Behçet's Disease. Information on the subjects was obtained through questionnaires. Tests, including those for hearing impairment, tinnitus, ear fullness, and dizziness, pure-tone audiometry, and vestibular function, were performed. RESULTS: Auditory symptoms were reported by 7 (41.2%) and dizziness by 14 (82.4%) of the subjects. Sensorineural hearing loss was present in four (23.5%) subjects. One was treated with a cochlear implantation because of bilateral sudden deafness. Spontaneous nystagmus was detected in two (11.8%) subjects. Abnormal findings were noted in 1 (5.9%) in saccadic movement, 5 (29.4%) in the bithermal caloric tests, and 10 (58.9%) in the rotation chair tests. In total, audiologic or vestibular disturbance were noted in 16 (94.1%) of the subjects. However, audio-vestibular abnormalities were not noted in the healthy controls. CONCLUSION: Audio-vestibular disturbance is not rare in Behçet's disease patients compared with healthy controls. We believe that audio-vestibular assessment and management may be helpful for the diagnosis and treatment of patients with Behçet's disease.

'Bow and lean test' to determine the affected ear of horizontal canal benign paroxysmal positional vertigo.

OBJECTIVE: One of the problems in the management of horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV) is the difficulty in determining the affected ear using Ewald's second law. The purpose of this study is to develop the new "bow and lean test (BLT)" to easily determine the affected ear of HSC-BPPV and evaluate its efficiency. METHODS: We compared the efficiency between the classic method and BLT in 26 patients with HSC-BPPV. The classic method is based on Ewald's second law comparing the intensity of nystagmus or symptoms in the head roll test. BLT is based on the direction of both "bowing nystagmus" and "leaning nystagmus" at the head's bowing and leaning state in a sitting position. The affected ear is the same direction of bowing nystagmus in canalolithiasis and the same direction of leaning nystagmus in cupulolithiasis. RESULTS: In 26 patents (15 canalolithiasis, 11 cupulolithiasis), 3 (11.5%) patients did not show a prominent affected ear in the classic method, and 7 (26.9%) patients showed the different affected ear between the two methods. All 10 patients were successfully treated with just one trial of barbecue rotation based on the affected ear in BLT. Three patients did not show any bowing or leaning nystagmus. The side with canal paresis in all four patients, who showed significant canal paresis in bithermal caloric tests, was equal to the affected ear based on BLT. CONCLUSIONS: The "bow and lean test" (also called "Choung's test") is a new method that can easily determine the affected ear of HC-BPPV.

Intratympanic dexamethasone injection for refractory sudden sensorineural hearing loss.

OBJECTIVE: This case-control study aimed to analyze the effect of intratympanic dexamethasone injection (ITDI) as a treatment option for patients with sudden sensorineural hearing loss (SSNHL) who were refractory to classic oral steroid treatment. METHODS: Sixty-six patients with SSNHL, who were refractory to a course of oral steroid therapy, were included in this study. We prospectively treated consecutive 33 patients (34 ears) with ITDI from August 2002 to January 2004. We then retrospectively collected data from age- and sex-matched previous patients who did not take any more treatments after the initial regimen between March 2000 and July 2002. ITDI was performed in the supine position on four separate occasions over the course of 2 weeks. Hearing was assessed immediately before every injection and at 1 week after therapy. Hearing improvement was defined as more than 10 dB in pure-tone average (PTA). RESULTS: Hearing improvement was observed in 13 (39.4%) of 33 patients who underwent ITDI and in two (6.1%) of 33 patients in the control group. Five of 13 represented hearing improvement over than 20 dB in PTA, and 11 of 20 patients, who showed no improvement in PTA by ITDI, showed improvement over 10 dB in some frequencies. There were no definite prognostic factors between the patients who responded to ITDI and those who did not. CONCLUSION: ITDI may be a simple and effective therapy for patients with refractory SSNHL.