Histopathological evaluation and long-term results of soft tissue preservation technique in cholesteatoma surgery.

The goal of cholesteatoma surgery is total removal of the cholesteatoma matrix and prevention of recurrence. Preservation of soft tissue in the attic is reported to improve post-operative middle ear aeration, and thus prevents recurrence. However, the histology and nature of the preserved tissue have rarely been reported. The aim of this study is to clarify the histology of the preserved soft tissue in cholesteatoma surgery, and to show its relationship to the clinical course. Surgical specimens were obtained from ten patients with pars flaccida-type cholesteatoma. In these patients, cholesteatoma occupied the attic and the mastoid cavity. The cholesteatoma was removed so as not to expose the bone in the attic. After the removal of the lesions, soft tissue was harvested from the floor of the attic, using cupped forceps. The specimens were fixed with 10 % formalin, and stained with hematoxylin-eosin. The patients were followed-up for 8 years after the surgery. No patients showed post-operative inner ear disturbance or facial nerve palsy. In one patient, residual lesion was found during the revision surgery. The area of residual lesion was not explored during the first operation. Two other patients showed recurrent cholesteatoma in the pars tensa; one of these patients had accompanying otorrhea. The other seven patients showed no residual or recurrent cholesteatoma 8 years after the surgery. The histological examination showed that the harvested tissue was mainly composed of collagen fiber and fibroblasts. Ciliary epithelial cells were found in one patient. In three patients, cysts of mucosal remnants (glandular cysts), were embedded in the connective tissue. Two of these three patients experienced recurrent cholesteatoma, while the other seven patients were without recurrence at follow-up. Preservation of soft tissue behind the cholesteatoma matrix is a safe technique if the surgical field is fully visible. In most cases, the preserved tissue was fibrous connective tissue and lacked the characteristics of mucosa. The glandular cysts in the preserved soft tissue seem to be related to the recurrence of cholesteatoma.

The sensitivity and accuracy of a cone beam CT in detecting the chorda tympani.

The facial recess approach through posterior tympanotomy is the standard approach in cochlear implantation surgery. The size of the facial recess is highly variable, depending on the course of the chorda tympani. Despite their clinical importance, little is known about the sensitivity and accuracy of imaging studies in the detection of the chorda tympani. A total of 13 human temporal bones were included in this study. All of the temporal bones were submitted to a cone beam CT (Accuitomo, Morita, Japan). The multi-planar reconstruction images were rotated around the mastoid portion of the facial nerve to locate the branches of the facial nerve. A branch was diagnosed as the chorda tympani when it entered the tympanic cavity near the notch of Rivinus. The distance between the bifurcation and the tip of the short crus of the incus was measured. In all temporal bones, the canal of the chorda tympani or the posterior canaliculus was detected. In the CT-based evaluation, the average distance from the bifurcation to the incus short crus was 12.6 mm (8.3-15.8 mm). The actual distance after dissection was 12.4 mm (8.2-16.4 mm). The largest difference between the distances evaluated with the two procedures was 1.1 mm. Cone beam CT is very useful in detecting the course of the chorda tympani within the temporal bone. The measured distance is accurate.

A randomized controlled clinical trial of topical insulin-like growth factor-1 therapy for sudden deafness refractory to systemic corticosteroid treatment.

BACKGROUND: To date, no therapeutic option has been established for sudden deafness refractory to systemic corticosteroids. This study aimed to examine the efficacy and safety of topical insulin-like growth factor-1 (IGF-1) therapy in comparison to intratympanic corticosteroid therapy. METHODS: We randomly assigned patients with sudden deafness refractory to systemic corticosteroids to receive either gelatin hydrogels impregnated with IGF-1 in the middle ear (62 patients) or four intratympanic injections with dexamethasone (Dex; 58 patients). The primary outcome was the proportion of patients showing hearing improvement (10 decibels or greater in pure-tone average hearing thresholds) 8 weeks after treatment. The secondary outcomes included the change in pure-tone average hearing thresholds over time and the incidence of adverse events. RESULTS: In the IGF-1 group, 66.7% (95% confidence interval [CI], 52.9-78.6%) of the patients showed hearing improvement compared to 53.6% (95% CI, 39.7-67.0%) of the patients in the Dex group (P = 0.109). The difference in changes in pure-tone average hearing thresholds over time between the two treatments was statistically significant (P = 0.003). No serious adverse events were observed in either treatment group. Tympanic membrane perforation did not persist in any patient in the IGF-1 group, but did persist in 15.5% (95% CI, 7.3-27.4%) of the patients in the Dex group (P = 0.001). CONCLUSIONS: The positive effect of topical IGF-1 application on hearing levels and its favorable safety profile suggest utility for topical IGF-1 therapy in patients with sudden deafness. TRIAL REGISTRATION: UMIN Clinical Trials Registry Number UMIN000004366, October 30th, 2010.

Childhood fever and hearing loss associated with CAPOS syndrome.

CAPOS (cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss) syndrome is a rare genetic disorder caused by the heterozygous mutation, c.2452G > A, in the ATP1A3 gene. CAPOS syndrome involves a characteristic episode in which neuropathy develops after a fever in childhood, and here, we describe the case of a patient with CAPOS syndrome. The patient had repeated episodes of a fever around 74 months of age. Although he could speak at 23 months of age, he presented with hearing difficulty after the fever. Pure-tone audiometry revealed moderate-to-severe bilateral sensorineural hearing loss, and auditory brainstem response (ABR) showed poor response in the both ears. Auditory stead-state response (ASSR) produced relatively consistent results compared to pure-tone audiometry. A mutation in the ATP1A3 gene was detected through genetic testing. In CAPOS syndrome, a genetic mutation leads to desynchronization during neural firing. We believe that this desynchronization in neural firing is responsible for the lack of response in the ABR and the presence of a response in the ASSR. In this patient, we attribute the response detection in ASSR to its greater tolerance for errors in the timing of neural firing compared to ABR.

A minimally invasive approach for cochlear implantation using a microendoscope.

Given the growing need for minimally invasive approaches to cochlear implantation surgery, we chose to examine the safety of a microendoscopic procedure for cochlear implantation. We performed cochlear implantation surgery on four human temporal bones using a microendoscope and evaluated the safety of the procedure. With a microendoscope, the facial recess was opened and electrodes were inserted into the cochlea. The size of the mastoidectomy ranged from 5 × 4 to 7 × 7 mm. For three of the temporal bones, the surgery was conducted without any damage to the surrounding structures. The chorda tympanic nerve was inadvertently sacrificed in one temporal bone, in which we skipped the identification of the incus. The microendoscope allowed cochlear implantation surgery to be performed with a mastoidectomy of minimal size.

Rapid detection of bacterial DNA in mastoid granulation tissue with nested-PCR technique.

OBJECTIVE: To detect bacterial DNA in mastoid granulation tissue from patients with chronic suppurative otitis media (CSOM). MATERIAL AND METHOD: A two-step polymerase chain reaction (nested polymerase chain reaction) technique was employed. A 16s rRNA universal primer common to all bacteria was used as a bracket primer for the first step PCR reaction. Primers specific to P aeruginosa and S. aureus were then used as nested primers for the second step PCR. Products of this process were identified by DNA sequencing. RESULTS: Among 15 clinical specimens collected, five showed positive bands specific to the species P aeruginosa, and 11 showed bands specific to the genus Staphylococcus. DNA sequencing showed 99.7 to 100% accuracy for target organisms in clinical specimens with a positive signal. The average time taken to conduct the PCR procedure was about four hours CONCLUSION: The nested PCR technique described worked well, even when the size of the mastoid granulation tissue was very small.

Systemic cisplatin increases the number of patients showing positive off-frequency masking audiometry.

OBJECTIVE: The study aimed to evaluate the effect of systemic cisplatin administration on off-frequency masking audiometry. METHODS: Among 26 patients receiving systemic cisplatin, 48 ears were included in the analysis. All patients underwent pure-tone audiometry with ipsilateral narrow-band masking noise (off-frequency masking audiometry). In the off-frequency masking audiometry, 70 dBHL band-pass noise (center frequency 1000 Hz, 1/3 octave bandwidth) was administered to the tested ear. The acquired thresholds were compared to those of standard pure-tone audiometry, and threshold elevations greater than 10 dB were regarded as significant. The number of patients showing abnormal threshold elevation was compared between before and after the cisplatin administration. RESULTS: Before cisplatin administration, 91.7, 93.8, 97.9, and 93.8% of ears showed normal off-frequency masking audiometry outcomes at 125, 250, 6000, and 8000 Hz, respectively. After cisplatin administration, a higher number of patients showed abnormal off-frequency masking audiometry outcomes. This change was more prominent with increasing doses of cisplatin. After the cisplatin administration of 100∼200 mg/m2, the prevalence of patients with normal off-frequency masking audiometry outcomes was 77.3, 70.5, 90.9, and 88.6% at 125, 250, 6000, and 8000 Hz, respectively. At 250 Hz, the change was statistically significant (p = 0.01, chi-squared test).

A Case of Actinomycosis in the Rosenmüller's Fossa.

Actinomycosis is an infrequent infectious disease caused by Actinomyces species. Actinomycoses in the nasopharynx are extremely rare, especially in the Rosenmüller's fossa. This report presents a case of actinomycosis in the Rosenmüller's fossa. A 75-year-old woman presented with a 6-month history of bloody sputum. A grayish-white caseous tissue was found in the right Rosenmüller's fossa after retracting the torus tubarius. Magnetic resonance imaging showed a well-defined lesion with low-signal intensity on T1- and T2-weighted images; small low-signal areas were interspersed inside. The lesion was removed under an endoscope. Histopathological examination revealed eosinophilic, club-shaped structures surrounding a hematoxylophilic center, leading to the diagnosis of actinomycosis. The symptoms improved after 3 months of amoxicillin administration but recurred quickly. After 6 months of amoxicillin administration, the bloody sputum disappeared, and local and imaging findings were normal.

[Clinical outcomes cochlear reimplantation].

To clarify the clinical features of cochlear reimplantation and surgical changes in auditory performance, we retrospectively reviewed 10 of 252 cochlear implantation surgeries-6 adults and 4 children-among 129 children and 123 adults done between April 1987 and May 2009. Mean duration from initial implantation to reimplantation was 50.3 months in children and 89 months in adults, most commonly due to hard failure and implant exposure/infection (33%) in children and to hard failure (75%) in adults. The initial device implanted was the Nucleus multichannel implant (CI22M, CI24M, or CI24R). The second implant in 7 was the same or an upgrade of the same manufacturer's device, and in 2 children the HiRes 90K (Hifocus 1j) and in 1 adult the Clarion 1.2. Full initial and reinsertion succeeded in 8 cases but reinsertion proved difficult in 2 due to severe intracochlear granulation and osteoneogenseis. Auditory performance analyzed in 7 cases was mostly equal to or better than before reimplantation, although differences were not statistically significant. Reinsertion is rarely difficult, but electrode choice is important in preparing for difficult reinsertion. Post reinsertion auditory performance is satisfactory with some exceptions.

Effect of hearing aids on body balance function in non-reverberant condition: A posturographic study.

OBJECTIVE: The purpose of this study was to evaluate the effect of hearing aids on body balance function in a strictly controlled auditory environment. METHODS: We recorded the findings of 10 experienced hearing aid users and 10 normal-hearing participants. All the participants were assessed using posturography under eight conditions in an acoustically shielded non-reverberant room: (1) eyes open with sound stimuli, with and without foam rubber, (2) eyes closed with sound stimuli, with and without foam rubber, (3) eyes open without sound stimuli, with and without foam rubber, and (4) eyes closed without sound stimuli, with and without foam rubber. RESULTS: The auditory cue improved the total path area and sway velocity in both the hearing aid users and normal-hearing participants. The analysis of variance showed that the interaction among eye condition, sound condition, and between-group factor was significant in the maximum displacement of the center-of-pressure in the mediolateral axis (F [1, 18] = 6.19, p = 0.02). The maximum displacement of the center-of-pressure in the mediolateral axis improved with the auditory cues in the normal-hearing participants in the eyes closed condition (5.4 cm and 4.7 cm, p < 0.01). In the hearing aid users, this difference was not significant (5.9 cm and 5.7 cm, p = 0.45). The maximum displacement of the center-of-pressure in the anteroposterior axis improved in both the hearing aid users and the normal-hearing participants.

Multicenter Study of Congenital Middle Ear Anomalies. Report on 246 Ears.

OBJECTIVES/HYPOTHESIS: Congenital middle ear anomalies represent a relatively rare condition. This study aimed to describe the characteristics and the surgical outcomes for patients with middle ear anomalies. METHODS: A multicenter study was conducted of consecutive patients with congenital middle ear anomalies who underwent primary surgical treatment between January 2008 and December 2017. Demographics, surgical procedures, and audiometric data were registered into the institutional database. Hearing changes and postoperative air-bone gap (ABG) were evaluated 1 year after surgery. RESULTS: A total of 246 patients (246 ears) (median age: 14 years, range: 4-75 years old) were included in this study. Anomalies were subdivided using the Teunissen and Cremers classification: 53 ears (22%) were categorized as class I, comprising only stapes ankylosis; 35 ears (14%) as class II, having ossicular chain anomalies with stapes ankylosis; 139 ears (57%) as class III, having ossicular chain anomalies with a mobile stapes-footplate; and 19 ears (8%) as class IV, with aplasia of the oval window. Evaluation of hearing outcomes for 198 ears with more than 1 year of follow-up revealed that good postoperative ABG (≤20 dB) was achieved in 82% of class I, 68% of class II, 74% of class III, and 23% of class IV anomalies. The postoperative ABG in class IV was significantly worse than in class I (P < .001) or class III (P < .01). CONCLUSIONS: This study demonstrated that class III anomalies comprised the majority of middle ear anomalies and surgical outcomes for class IV anomalies are unfavorable. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E2323-E2328, 2021.

Topical insulin-like growth factor 1 treatment using gelatin hydrogels for glucocorticoid-resistant sudden sensorineural hearing loss: a prospective clinical trial.

BACKGROUND: Sudden sensorineural hearing loss (SSHL) is a common condition in which patients lose the hearing in one ear within 3 days. Systemic glucocorticoid treatments have been used as standard therapy for SSHL; however, about 20% of patients do not respond. We tested the safety and efficacy of topical insulin-like growth factor 1 (IGF1) application using gelatin hydrogels as a treatment for SSHL. METHODS: Patients with SSHL that showed no recovery to systemic glucocorticoid administration were recruited. We applied gelatin hydrogels, impregnated with recombinant human IGF1, into the middle ear. The primary outcome measure was the proportion of patients showing hearing improvement 12 weeks after the test treatment. The secondary outcome measures were the proportion of patients showing improvement at 24 weeks and the incidence of adverse events. The null hypothesis was that 33% of patients would show hearing improvement, as was reported for a historical control after hyperbaric oxygen therapy. RESULTS: In total, 25 patients received the test treatment at a median of 23 days (range 15-32) after the onset of SSHL, between 2007 and 2009. At 12 weeks after the test treatment, 48% (95% CI 28% to 69%; P = 0.086) of patients showed hearing improvement, and the proportion increased to 56% (95% CI 35% to 76%; P = 0.015) at 24 weeks. No serious adverse events were observed. CONCLUSIONS: Topical IGF1 application using gelatin hydrogels is well tolerated and may be efficacious for hearing recovery in patients with SSHL that is resistant to systemic glucocorticoids.

Central processing of speech sounds and non-speech sounds with similar spectral distribution: An auditory evoked potential study.

OBJECTIVE: The purpose of this study was to measure the auditory evoked potentials for speech and non-speech sounds with similar spectral distributions. METHODS: We developed two types of sounds, comprising naturally spoken vowels (natural speech sounds) and complex synthesized sounds (synthesized sounds). Natural speech sounds consisted of 5 Japanese vowels. Synthesized sounds consisted of a fundamental frequency and its second to fifteenth harmonics equivalent to those of natural speech sounds. The synthesized sound was filtered to have a similar spectral distribution to that of each natural speech sound. These sounds were low-pass filtered at 2000 Hz. The auditory evoked potential elicited by the natural speech sound /o/ and synthesized counterpart for /o/ were measured in 10 right-handed healthy adults with normal hearing. RESULTS: The natural speech sounds were significantly highly recognized as speech compared to the synthesized sounds (74.4% v.s. 13.8%, p < 0.01). The natural speech and synthesized sounds for the vowel /o/ contrasted strongly for speech perception (96.9% vs. 9.4%, p <0.01). However, the vowel /i/ and its counterpart were barely recognized as speech (4.7 v.s. 3.1%, p = 1.00). The N1 peak amplitudes and latencies evoked by the natural speech sound /o/ were not different from those evoked by the synthesized sound (p = 0.58 and p = 0.28, respectively). The P2 amplitudes evoked by the natural speech sound /o/ were not different from those evoked by the synthesized sound (p = 0.51). The P2 latencies evoked by the natural speech sound /o/ were significantly shorter than those evoked by the synthesized sound (p < 0.01). This modulation was not observed in a control study using the vowel /i/ and its counterpart (p = 0.29). CONCLUSION: The early P2 observed may reflect central auditory processing of the 'speechness' of complex sounds.

Efficiency of a transtympanic approach to the round window membrane using a microendoscope.

There has been increasing interest in cochlear drug delivery through the round window membrane (RWM). However, placing drugs on the RWM is difficult because of anatomical barriers. We examined the efficacy of a microendoscope for a transtympanic approach to the RWM. We evaluated the visibility of the RWM using four approaches: transtympanic microendoscopic, transtympanic microscopic, transmastoid microendoscopic, and transmastoid microscopic in ten human temporal bones. For the transtympanic approach, we made a fenestration (2 x 1 mm) in the postero-inferior quadrant of the tympanic membrane. For the transmastoid approach, conventional posterior hypotympanotomy was performed. The transtympanic microendoscopic approach enabled visualization of the RWM in all specimens, whereas the transtympanic microscopic approach only permitted visualization in three specimens. Through the transmastoid approach, the RWM was visible in all specimens using either a microendoscope or a microscope. The transtympanic microendoscopic approach can be utilized for cochlear drug delivery through the RWM.

Detectability of minute temporal bone structures with ultra-high resolution CT.

OBJECTIVE: Computed tomography (CT) is the imaging tool of choice in the diagnosis of temporal bone lesions. With the recent progress in imaging technology, CT with higher spatial resolution (Ultra-high resolution CT) has become available in the clinical setting. The purpose of this study is to evaluate the visibility of small temporal bone structures using ultra-high resolution CT. MATERIAL AND METHODS: The visibility of 27 minute temporal bone structures on ultra-high resolution CT images was evaluated. Non-helical axial scans were performed in 18 normal hearing ears without previous otologic diseases. Visibility was scored by an experienced radiologist and otologist. RESULTS: Minute temporal bone structures including the ossicular chain, the crus of the stapes, the greater superficial petrosal nerve, and the anterior malleolar ligament were clearly visualized on ultra-high resolution CT. The stapedius muscle tendon and the chorda tympani exiting the posterior canaliculus and coursing medial to the malleus could be visualized. CONCLUSION: Ultra-high resolution CT provides good visualization of small temporal bone structures in normal subjects.

Intraoperative Evaluation of Cochlear Implant Electrodes Using Mobile Cone-Beam Computed Tomography.

OBJECTIVE: To evaluate the electrode status during cochlear implantation (CI) using mobile cone-beam CT (mCBCT). STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral hospital. PATIENTS: Fifty-seven patients (7 bilateral surgeries, 64 ears) who underwent CI and who received intraoperative mCBCT imaging. INTERVENTION: CI and CBCT during surgery. MAIN OUTCOME MEASURE: Electrode location and angular insertion depth determined by intraoperative mCBCT images. RESULTS: There were six cases with cochlear malformation where intraoperative mCBCT was useful to confirm electrode location. Of 58 ears with a normal cochlear morphology, perimodiolar, straight, and mid-scalar electrodes were used in 30 (cochleostomy; 14 advance off-stylet technique cases), 27 (26 round window [RW] insertion, 1 extended round window [ERW] insertion), and 1 (RW insertion) ears, respectively. Complete scala-tympani (ST) insertion was achieved in 35 ears (14 cochleostomy, 21 RW or ERW insertion). The complete ST-insertion rate was significantly higher with RW or ERW insertion than that for cochleostomy insertion (p = 0.03), although cochleostomy insertion using the advanced off-stylet technique had a similar rate to RW or ERW insertion. The angular insertion depth values (average ±â€Šstandard deviation) for perimodiolar electrodes (354.4 ±â€Š29.44 degrees) were significantly smaller than those for Flex24 (464.8 ±â€Š43.09 degrees) and Flex28 (518.2 ±â€Š61.91 degrees) electrodes (p < 0.05). CONCLUSIONS: Evaluation of CI electrodes using intraoperative mCBCT was comparable to that with fan-beam CT or c-arm-based CBCT. Considering the low radiation dose of mCBCT and its availability in any operation room, mCBCT is the better modality for evaluating cochlear implant electrode arrays.

Intraoperative cochlear nerve monitoring in vestibular schwannoma surgery--does it really affect hearing outcome?

OBJECTIVE: The objective of this study was to examine the usefulness of intraoperative cochlear nerve monitoring (ICNM) in the preservation of normal and social hearing in vestibular schwannoma (VS) removal. METHODS: A retrospective chart review was conducted. Of 1315 patients operated for VS between June 1988 and December 2005, 150 patients were subjected to hearing preservation surgery. Among these, 99 patients with preoperative normal and social hearing (class A and B in the modified Sanna classification) and with a small tumor <1.5 cm in size were included in the analysis. The difference in hearing preservation rates between patients operated with and without ICNM was statistically examined using Fisher's exact test. An initial analysis was conducted for the total group. Patients were then divided into two subgroups according to the surgical approach (middle cranial fossa and retrosigmoid-retrolabyrinthine). The effectiveness of ICNM in each subgroup was analyzed. RESULTS: The hearing preservation rate was 26.7% in cases operated with ICNM and 20.8% in cases without ICNM. The difference did not reach statistical significance (p = 0.79). In subgroup analyses, the ICNM did not prove to contribute to the significantly higher hearing preservation rate. CONCLUSIONS: ICNM did not increase the ratio of patients with postoperative normal and social hearing in VS surgery.

Cochlear implant function in a patient with Jervell and Lange-Nielsen syndrome after defibrillation by countershock.

Jervell and Lange-Nielsen syndrome (JLNS), a rare autosomal recessive congenital QT prolongation syndrome, is characterized by cardiac arrhythmias, syncopal episodes, and profound deafness. A cochlear implant (CI) for patients with JLNS is expected to result in hearing improvement. Sometimes, defibrillation is required if a patient experiences lethal arrhythmia. In this paper, we report a pediatric patient with JLNS who received defibrillation after CI surgery in his right ear at the age of 2 years. With intensive care, the post-operative course was uneventful, and the patient acquired satisfactory speech and hearing abilities. Five years after the surgery, he underwent defibrillation because of the incidence of syncopal attack. Thereafter, arrhythmic syncope recurred three times, which necessitated defibrillation therapy. To prevent recurrence of cardiac arrhythmia, he underwent ICD (implantable cardioverter-defibrillator) implantation at the age of 11 years. At present, CI works well and provides good hearing, while syncopal attack is prevented by ICD. From the experience of this case, electronic circuit of CI is thought to tolerate emergency countershock if the speech processor is removed.

Body balance function of cochlear implant patients with and without sound conditions.

OBJECTIVE: The relation between well-controlled auditory stimulation through cochlear implant (CI) and the body balance has been sparsely investigated. The purpose of this study was to evaluate the body balance function of CI patients with- and without-sound in anechoic sound-shielded room. METHODS: We recorded 8 experienced CI recipients and 8 young normal-hearing volunteers. All subjects were assessed using posturography under 4 conditions: (1) eyes open with-sound, (2) eyes closed with-sound, (3) eyes open without-sound, and (4) eyes closed without-sound. RESULTS: The total path length and the total area were significantly larger in the eyes closed condition than in the eyes open condition. In normal hearing subjects, the average displacement of center of pressure (COP) in the mediolateral direction under with-sound condition was not different from that under without-sound condition. In CI recipients, the COP significantly displaced to the CI side after the deprivation of visual cues in without-sound condition. This shift was eliminated in with-sound condition (significant interaction among sound condition, eye condition, and between-group factor). CONCLUSION: In CI subjects, sound stimulation improves the abnormal displacement of COP in the mediolateral direction. SIGNIFICANCE: A posturographic study under an anechoic condition proved that sound stimulation improves body balance function in CI subjects.