In vitro Inhibition of Clinical Isolates of Otitis Media Pathogens by the Probiotic Streptococcus salivarius BLIS K12.

Otitis media is a common childhood infection, frequently requiring antibiotics. With high rates of antibiotic prescribing and increasing antibiotic resistance, new strategies in otitis media prevention and treatment are needed. The aim of this study was to assess the in vitro inhibitory activity Streptococcus salivarius BLIS K12 against otitis media pathogens. Efficacy of the bacteriocin activity of S. salivarius BLIS K12 against the otitis media isolates was assessed using the deferred antagonism test. Overall, 48% of pathogenic isolates exhibited some growth inhibition by S. salivarius BLIS K12. S. salivarius BLIS K12 can inhibit the in vitro growth of the most common pathogens.

Pharmacological Issues in Hearing Rehabilitation.

Surgery aimed at hearing rehabilitation risks damaging residual inner ear function, especially cochlear implant surgery. Pharmacological intervention to reduce this risk has shown great promise in animal models. The challenge is to deliver medication to the appropriate part of the inner ear in appropriate concentrations for long enough to be effective. Barriers to achieving these goals include: the blood/labyrinth barrier, limiting systemic drug delivery to the inner ear, slow rates of diffusion from the base of the cochlea to the apex, limiting intratympanic delivery from the middle ear to the cochlear apex, delayed intracochlear fibrosis, requiring extended medication delivery postoperatively. Intracochlear drug delivery via a drug-eluting cochlear implantation (CI) electrode may solve many of these pharmacologic issues. It is likely that more than one medication will be necessary to maximize inner ear protection and this may include steroids and appropriate growth factors. Such protection may also be helpful for otologic surgical procedures other than CI that have lower risks to hearing.

Patterns of Extended High-frequency Hearing Loss Following Stapes Surgery.

OBJECTIVE: Thresholds in the extended high-frequency (EHF) range (> 8 kHz) often worsen after otherwise successful stapedectomy. The aims of this study were to document the prevalence of hearing loss from 0.25 to 16 kHz after stapedectomy and the relative rates of transient and permanent EHF hearing loss. STUDY DESIGN: Prospective, observational, longitudinal. SETTING: Tertiary referral center. PATIENTS: Thirty-nine patients who underwent 44 primary or revision stapes surgeries. INTERVENTION: Hearing thresholds were measured at 0.25 to 16 kHz preoperatively, and at approximately 1 week, 1, 3, 6, and 12 months postoperatively. MAIN OUTCOME MEASURES: Average threshold changes in bands of frequencies (0.25-1, 2-8, 9-11.2, 12.5-16 kHz) and the percentage of patients with a change in the highest frequency at which a hearing threshold could be measured were evaluated at each assessment. RESULTS: A mean hearing loss was documented in the EHF range at all postoperative assessments. There was a decrease in the highest frequency at which a hearing threshold was measureable in 77% of patients at the first postoperative assessment, and despite some improvement over time, in 50% of patients 12 months postoperatively. CONCLUSION: There is a significant incidence of EHF loss after stapedectomy. Although partial recovery often occurs, more than half of patients retain an EHF hearing loss 12 months postoperatively. As hearing loss in the EHF range is more common than loss at 4 kHz, EHF measurements may be a more sensitive model to compare surgical factors and evaluate pharmacologic interventions.

Stapedectomy in Teunissen-Cremers Syndrome: Intraoperative Findings and Hearing Outcomes.

OBJECTIVE: To describe the intraoperative findings and outcomes of stapedectomy surgery in Teunissen-Cremers syndrome. PATIENTS: A family of three patients with bilateral conductive hearing loss because of Teunissen-Cremers syndrome. INTERVENTION: Six exploratory tympanotomies and stapedectomies, including one revision operation. MAIN OUTCOME MEASURES: Intraoperative findings and postoperative hearing results. RESULTS: There was an increased distance between the incus and the vestibule, a thicker long process of the incus, and slight variation in the relative position of the ossicles in all patients. Surgery resulted in closure of the air-bone gap to less than 10 dB in all five operated ears. CONCLUSION: We describe anatomic abnormalities of the ossicular chain in Teunissen-Cremers syndrome. Prosthesis availability should include prostheses that can adapt to these potential anatomic abnormalities. Stapedectomy resulted in good long-term hearing outcomes in this series.

An audit of paediatric referrals to the Southern Cochlear Implant Programme (2009-2014).

AIM: To determine the effect of the Universal Newborn Hearing Screening and Early Intervention Programme on the age of referral and implantation of prelingually deaf children in the Southern Cochlear Implant Programme. METHOD: A retrospective review of data collected prospectively from March 2003 to August 2014. RESULTS: 123 children were referred to the programme with prelingual deafness in the time period. There was a significant decrease in the age of referral (median 6.23 months vs. 21.50 months) and age at implantation (12.66 months vs. 24.0 months) in those that underwent newborn hearing screening. Reasons for delay in referral and implantation were identified. CONCLUSION: The introduction of universal newborn hearing screening has significantly reduced the age at referral and implantation of prelingually deaf children. However, the screening programme must continue to undergo monitoring and regular audit. Efforts must also be made to reduce the time to referral, including reducing non-attendance rates, education for parents and service providers, and earlier referral of those with comorbidities so as to reduce the time to implantation.

Mastoid pneumocoele with skull base and cervical spine pneumatisation.

Very uncommonly, Eustachian tube dysfunction can lead to symptomatic chronic elevation of middle ear pressure with aeration of bone and adjacent structures in the skull base and upper cervical spine, and an increased risk of fracture. We present a case demonstrating the natural history of this condition over 11 years before treatment and 10 months after treatment.

Patterns of hearing loss following retrosigmoid excision of unilateral vestibular schwannoma.

Objectives To determine the pattern of auditory responses, time-course of hearing deterioration, and possible site of lesion following retrosigmoid excision of unilateral vestibular schwannomas. Design Prospective, nonrandomized, observational pilot study. Setting Tertiary referral medical center. Main outcome measures Preoperative and postoperative pure-tone and speech audiometry, auditory brainstem response testing, and distortion product otoacoustic emissions were performed in 20 patients. Testing was conducted every 24 hours for the duration of hospitalization. Transtympanic electrocochleography was performed if delayed deterioration of auditory responses was documented. Results Of the 20 patients, 7 had no discernible cochlear nerve at the end of the procedure. Of the 13 patients with an intact nerve, 6 retained hearing, 3 with evidence of reduced neural function. Of the 7 who lost hearing despite an intact nerve, 5 lost at least cochlear and possibly also neural function, and 1 had reduced neural function but retained cochlear function. There were two examples of delayed deterioration of cochlear nerve responses. Conclusions Hearing loss following retrosigmoid removal of vestibular schwannomas most often involves loss of at least cochlear function, possibly in addition to neural damage. In a smaller number of cases anacusis or hearing deterioration can be attributed to purely neural trauma.

Intratympanic versus intravenous delivery of dexamethasone and dexamethasone sodium phosphate to cochlear perilymph.

OBJECTIVE: To measure dexamethasone concentrations in the plasma and perilymph of the human ear after intravenous (IV) and intratympanic (IT) administration and to compare these with previous studies with methylprednisolone. METHODS: Patients were administered dexamethasone by the IT or IV routes approximately 0.5 to 2 hours before cochlear implantation. The IT dose of 1.6 to 7.2 mg (0.4-1.8 ml of a 4 mg/ml solution) of dexamethasone sodium phosphate was administered by injection into the middle ear cavity through the external auditory canal via a 27-gauge needle passed through a small anterosuperior myringotomy. The IV dose of dexamethasone sodium phosphate was 0.17 mg/kg given as a single injection for 30 seconds. A sample of perilymph (approximately 20 µl) was collected using a needle passed through the round window, and blood was sampled simultaneously. Concentrations of free dexamethasone and dexamethasone sodium phosphate were measured using a validated liquid chromatography-tandem mass spectrometry method. RESULTS: In the 22 patients studied, 22 perilymph samples and 19 plasma samples were available and suitable for measurement. The median perilymph concentration of dexamethasone after IV injection of 0.17 mg/kg was 0.016 mg/L (n = 9; range, 0.008-0.17), and 1.4 mg/L (n = 13; range, 0.1-16.3) after IT administration of approximately 4 mg. Perilymph concentrations were approximately 88-fold higher after IT compared with IV administration (p = 0.0004) or approximately 260 fold after correction for dosage. The median plasma concentration of dexamethasone after IV injection was 0.12 mg/L (n = 7; range, 0.07-0.14) and 0.003 mg/L (n = 12; range, <0.0005-0.005) after IT injection. Plasma concentrations were approximately 40-fold lower (p = 0.0005) or approximately 13-fold lower after dose correction. Concentrations of dexamethasone sodium phosphate were more variable and were even higher in perilymph and lower in plasma. CONCLUSION: Administration of dexamethasone IT results in much higher perilymph concentrations and much lower plasma concentrations compared with IV administration.

Determination of dexamethasone and dexamethasone sodium phosphate in human plasma and cochlear perilymph by liquid chromatography/tandem mass spectrometry.

A rapid, simple and sensitive liquid chromatography/tandem mass spectrometry (LC-MS/MS) assay was developed for the determination of dexamethasone (Dex) and dexamethasone sodium phosphate (Dex SP) in plasma and human cochlear perilymph. After proteins were precipitated with a mixture of acetonitrile and methanol, Dex, Dex SP and flumethasone, the internal standard, were resolved on a C18 column using gradient elution of 5 mM ammonium acetate and methanol. The three compounds were detected using electrospray ionisation in the positive mode. Standard curves were linear over the concentration range 0.5-500 µg/L (r>0.99), bias was <±10%, intra- and inter-day coefficients of variation (imprecision) were <10%, and the limit of quantification was 0.5 µg/L for both Dex and Dex SP. The assay has been used successfully in a clinical pharmacokinetics study of Dex and Dex SP in cochlear perilymph and plasma.

Cochlear Implantation in children with CHARGE syndrome.

UNLABELLED: CHARGE syndrome is a rare congenital condition that manifests with anomalies of coloboma, heart defects, choanal atresia, mental retardation, genitourinary and ear anomalies that can affect almost any part of the auditory pathway. In those patients with a significant sensorineural hearing loss, cochlear implantation has become a potential therapeutic option. METHODS: Chart review of three cases from the Southern Cochlear Implant Programme. OUTCOMES: All patients met clinical diagnostic criteria of CHARGE syndrome, and had abnormal inner ear anatomy with profound sensorineural hearing loss. One child had previously undergone cochlear implantation which was unsuccessful due to increasing non-auditory stimulation. All patients had successful cochlear implantation with full insertion of a Nucleus Freedom Implant with contour Advance. All patients showed improvement in their audiological function; one child has high functioning verbal communication, one child uses both sign and verbal communication with improved speech quality and ability to speech read, and one child responds reliably to sound, understands short phrases and attempts to vocalize, but this is limited by tracheostomy. CONCLUSION: Cochlear implantation faces numerous challenges in children with CHARGE syndrome, but with appropriate patient selection can result in successful audiologic and quality of life outcomes.

Unsuccessful cochlear implantation in two patients with superficial siderosis of the central nervous system.

OBJECTIVE: To highlight the potential adverse outcomes with cochlear implantation (CI) in patients with superficial siderosis. PATIENTS: Two patients with superficial siderosis of the central nervous system with secondary sensorineural hearing loss. INTERVENTION: Cochlear implantation. MAIN OUTCOME MEASURE: Postimplantation speech discrimination scores. RESULTS: In both cases, initial results after implantation were promising. However, in 1 case, their ability to use the CI rapidly declined after 1 week because of major difficulties adapting to electrical stimulation. For the other case, hearing rapidly declined over a 6-month period. CONCLUSION: The 2 patients reported did not benefit from CI in superficial siderosis that is in contrast to several previously published cases. Adequate counseling of patients with superficial siderosis is important when considering cochlear implantation as results are variable.

Intratympanic versus intravenous delivery of methylprednisolone to cochlear perilymph.

OBJECTIVE: To compare methylprednisolone concentrations in the perilymph of the human ear and in plasma after intratympanic (IT) or intravenous (IV) administration. METHODS: Methylprednisolone concentrations in the perilymph of patients during cochlear implantation were compared after 3 dosing strategies of methylprednisolone solution for injection (40 mg/ml): 1) IT administration of up to 40 mg was injected into the middle ear through the external auditory canal via a 27-gauge needle passed through a small anterosuperior myringotomy; 2) IV administration of 1 mg/kg was given as a single injection over 30 seconds; 3) IV administration of 10 mg/kg was infused over 30 minutes. Perilymph (single sample, approximately 20 microL) was sampled using a needle passed through the round window membrane, from 0.5 to 3 hours after dosing. In most patients, simultaneous blood sampling was performed. Methylprednisolone concentrations were measured by high-performance liquid chromatography with a limit of quantification of 0.001 mg/L. RESULTS: In 39 patients studied, 33 perilymph samples were suitable for measurement, along with 26 plasma samples. Median perilymph concentrations were 6.7 mg/L (n = 18; range, 0.2-89.4 mg/L) after IT administration, 0.053 mg/L (n = 8; range, 0-0.47 mg/L) after IV injection of 1 mg/kg, and 0.2 mg/L (n = 7; range, 0.067-3.1 mg/L) after IV infusion of 10 mg/kg. The median perilymph concentrations were 126-fold higher after the IT administration than after 1 mg/kg IV (p = 0.0003) and 33-fold higher than after 10 mg/kg IV infusion (p = 0.0045). Plasma concentrations after IT administration were 16-fold lower than after IV administration of 1 mg/kg (p = 0.0006), and 136-fold lower than after IV infusion of 10 mg/kg (p = 0.0006). CONCLUSION: IT administration of methylprednisolone in humans results in much higher perilymph concentrations and much lower systemic concentrations than IV administration.

Giant cell reparative granuloma of the temporal bone treated with calcitonin.

OBJECTIVE: A case report of a giant cell reparative granuloma involving the temporal bone successfully treated with calcitonin. STUDY DESIGN: Case report. SETTING: Teaching hospital, tertiary referral center. PATIENT, INTERVENTION, AND RESULTS: A 62-year-old man was referred to the otolaryngology department with an extensive temporal bone lesion confirmed by biopsy to be a giant cell reparative granuloma. As an alternative to surgery, calcitonin therapy was commenced. After 12 months of treatment, clinical and audiological parameters had returned to normal, and radiological appearances had shown significant bony remodeling. These parameters remain stable 24 months after cessation of treatment. CONCLUSION: Calcitonin is a safe and economical medical treatment, which should be considered for destructive giant cell granulomas of the temporal bone.

Facial nerve function and hearing preservation after retrosigmoid excision of vestibular schwannoma: Christchurch Hospital experience with 97 patients.

BACKGROUND: Between January 1988 and December 2002, 97 patients underwent surgery for excision of vestibular schwannoma via the retrosigmoid approach at Christchurch Hospital. METHODS: A retrospective review was undertaken of the clinical notes with emphasis on facial nerve function and hearing preservation postoperatively. RESULTS: Of patients with small and medium-sized tumours, 81% had good facial nerve function at 1 year (House-Brackmann grade 1 and grade 2), 16% had moderate function (grade 3 and grade 4) and 3% had poor function (grade 5). Of patients with large tumours, 22% had good facial function (grade 1 and grade 2), 37% had moderate function (grade 3 and grade 4) and 41% had poor function (grade 5 and grade 6). Useful postoperative hearing was preserved in 21% of the 47 patients with tumours <3 cm and useful preoperative hearing. In the last 5 years the authors have been operating in conjunction with an ear, nose and throat surgeon (PAB) trained in base-of-skull surgery. Over this period, useful hearing was preserved in 32% of patients with small and medium-sized tumours and useful preoperative hearing. CONCLUSIONS: Tumour size was an important predictor of the postoperative facial and cochlear nerve function. The multidisciplinary approach to these tumours offers better results. These results compare well with other published series.