Does Intraoperative Extracochlear Electrocochleography Correlate With Postoperative Audiometric Hearing Thresholds in Cochlear Implant Surgery? A Retrospective Analysis of Cochlear Monitoring.

In recent years, tools for early detection of irreversible trauma to the basilar membrane during hearing preservation cochlear implant (CI) surgery were established in several clinics. A link with the degree of postoperative hearing preservation in patients was investigated, but patient populations were usually small. Therefore, this study's aim was to analyze data from intraoperative extracochlear electrocochleography (ECochG) recordings for a larger group.During hearing preservation CI surgery, extracochlear recordings were made before, during, and after CI electrode insertion using a cotton wick electrode placed at the promontory. Before and after insertion, amplitudes and stimulus response thresholds were recorded at 250, 500, and 1000 Hz. During insertion, response amplitudes were recorded at one frequency and one stimulus level. Data from 121 patient ears were analyzed.The key benefit of extracochlear recordings is that they can be performed before, during, and after CI electrode insertion. However, extracochlear ECochG threshold changes before and after CI insertion were relatively small and did not independently correlate well with hearing preservation, although at 250 Hz they added some significant information. Some tendencies-although no significant relationships-were detected between amplitude behavior and hearing preservation. Rising amplitudes seem favorable and falling amplitudes disadvantageous, but constant amplitudes do not appear to allow stringent predictions.Extracochlear ECochG measurements seem to only partially realize expected benefits. The questions now are: do gains justify the effort, and do other procedures or possible combinations lead to greater benefits for patients?

Intratympanic application of triamcinolone in sudden hearing loss-radiologic anatomy in cone beam CT and its' correlation to clinical outcome.

PURPOSE: To evaluate temporal bone cone-beam CT in patients with idiopathic sudden sensorineural hearing loss (ISSNHL) being treated with primary and secondary intratympanic (IT) triamcinolone and to possibly correlate these results to the clinical outcome. METHODS: Retrospective analysis of patients treated with IT triamcinolone for ISSNHL at our department in 2018. Pre- and post-therapeutic audiologic examinations included four-tone average (FTA) at 0.5, 1, 2 and 3 kHz. Using a clinical questionnaire, pre-therapeutic CBCT scans were re-evaluated looking at items, which might interfere with adequate drug diffusion into the inner ear (e.g. bony overhangs or secondary membranes at the round or oval window). RESULTS: Thirty-one patients were included. Twenty-four (77%; group A) had experienced ineffective systemic steroid therapy before and seven (23%; group B) received primary IT injections. Four group A-patients (21%) and two group B-patients (33%) showed a post-therapeutic FTA improvement of more than 15 dB HL. Bony overhangs at the round window niche (RWN) were present in seven cases (26%), a secondary membrane at the RWN in four (15%) and soft tissue in eight (30%) cases, respectively. CONCLUSION: Most patients present radiological findings in CBCT imaging, which might interfere with drug diffusion through the RW membrane. Interestingly, soft or bony tissue obstructing the RWN or the OWN was found in 50% of patients, who showed improvement of hearing. We conclude that radiologic 'tiny' findings are either clinically irrelevant or improvement in hearing is independent from intratympanic drug delivery.

Monitoring of the Inner Ear Function During and After Cochlear Implant Insertion Using Electrocochleography.

To preserve residual hearing during cochlear implant (CI) surgery, it is desirable to use intraoperative monitoring of inner ear function (cochlear monitoring), especially during electrode insertion. A promising method is electrocochleography (ECochG). Within this project, the relations between ongoing responses (ORs), recorded extra- and intracochlearly (EC and IC), and preservation of residual hearing were investigated. Before, during, and after insertion of hearing preservation electrodes, intraoperative ECochG recordings were performed EC using a cotton wick electrode and after insertion also IC using the CI electrode (MED-EL) and a research software tool. The stimulation was delivered acoustically using low frequency tone bursts. The recordings were conducted in 10 adult CI recipients. The amplitudes of IC ORs were detected to be larger than EC ORs. Intraoperative EC thresholds correlated highly to preoperative audiometric thresholds at 1000 Hz, IC thresholds highly at 250 Hz and 500 Hz. The correlations of both intraoperative ECochG recordings to postoperative pure tone thresholds were low. When measured postoperatively at the same appointments, IC OR thresholds correlated highly to audiometric pure tone thresholds. For all patients, it was possible to record ORs during or directly after electrode insertion. Consequently, we conclude that we did not observe any cases with severe IC trauma. Delayed hearing loss could not be predicted with our method. Nevertheless, intraoperative ECochG recordings are a promising tool to gain further insight into mechanisms impacting residual hearing. Postoperatively recorded IC OR thresholds seem to be a reliable tool for frequency specific hearing threshold estimation.

Cochlear implantation in children with meningitis related deafness: The influence of electrode impedance and implant charge on auditory performance - A case control study.

OBJECTIVES: Bacterial meningitis can cause a labyrinthitis. Consequences often are intracochlear soft tissue neoformation (cochlear obliteration) or intracochlear osteoneogenesis (cochlear ossification) and deafness. Cochlear implantation becomes challenging and hearing rehabilitation is complicated. This retrospective case-control-study aimed to find correlations between morphologic, electric and functional parameters. METHODS: The study group included children, who lost hearing due to a bacterial meningitis (n = 35 cases). Using preoperative computed tomography and intraoperative findings we grouped into 'unaltered cochleae', 'obliterated cochleae' and 'ossified cochleae'. Control group children suffered from deafness (n = 16) of other aetiology and presented with radiologically unchanged cochleae. Postoperative routine controls documented impedances, stimulation charge and hearing tests a various time points, which all were analysed. RESULTS: Control group patients showed a mean impedance of 6.3 kΩ and the mean charge applied was 19 nC. The study group averaged at 7.9 kΩ and 24.6 nC respectively. Patients with ossified cochleae had increased values of 8.6 kΩ and 29.7 nC. The control group reached a monosyllabic word understanding of 74% and the study group of 58%. Patients with ossified cochleae reached 36%. CONCLUSIONS: Impedances and stimulation charge influence each other. Increased charge is necessary for higher cochlear implant output. Despite higher charges, patients with obliterated and patients with ossified cochleae significantly perform worse in hearing rehabilitation. Reduced audiological outcome in study group patients without morphologic cochlear changes furthermore hints at additional factors besides cochlear tissue neogenesis like postinflammational changes at the neural pathway.

The Summating Potential Is a Reliable Marker of Electrode Position in Electrocochleography: Cochlear Implant as a Theragnostic Probe.

OBJECTIVE: For the increasing number of cochlear implantations in subjects with residual hearing, hearing preservation, and thus the prevention of implantation trauma, is crucial. A method for monitoring the intracochlear position of a cochlear implant (CI) and early indication of imminent cochlear trauma would help to assist the surgeon to achieve this goal. The aim of this study was to evaluate the reliability of the different electric components recorded by an intracochlear electrocochleography (ECochG) as markers for the cochleotopic position of a CI. The measurements were made directly from the CI, combining intrasurgical diagnostics with the therapeutical use of the CI, thus, turning the CI into a "theragnostic probe." DESIGN: Intracochlear ECochGs were measured in 10 Dunkin Hartley guinea pigs of either sex, with normal auditory brainstem response thresholds. All subjects were fully implanted (4 to 5 mm) with a custom six contact CI. The ECochG was recorded simultaneously from all six contacts with monopolar configuration (retroauricular reference electrode). The gross ECochG signal was filtered off-line to separate three of its main components: compound action potential, cochlear microphonic, and summating potential (SP). Additionally, five cochleae were harvested and histologically processed to access the spatial position of the CI contacts. Both ECochG data and histological reconstructions of the electrode position were fitted with the Greenwood function to verify the reliability of the deduced cochleotopic position of the CI. RESULTS: SPs could be used as suitable markers for the frequency position of the recording electrode with an accuracy of ±1/4 octave in the functioning cochlea, verified by histology. Cochlear microphonics showed a dependency on electrode position but were less reliable as positional markers. Compound action potentials were not suitable for CI position information but were sensitive to "cochlear health" (e.g., insertion trauma). CONCLUSIONS: SPs directly recorded from the contacts of a CI during surgery can be used to access the intracochlear frequency position of the CI. Using SP monitoring, implantation may be stopped before penetrating functioning cochlear regions. If the technique was similarly effective in humans, it could prevent implantation trauma and increase hearing preservation during CI surgery. Diagnostic hardware and software for recording biological signals with a CI without filter limitations might be a valuable add-on to the portfolios of CI manufacturers.

Radiologic detectability of the cochlear implant electrode fixation clip using cone beam computed tomography.

INTRODUCTION: With the aim of preventing migration of cochlear implantation electrodes in the postoperative course, an electrode fixation clip has been developed. It is characterized by two clips of double U-geometry. The bone fixation clip will be clamped on the bony incus bridge, and the electrode fixation clip is clamped to the electrode lead. Although made of titanium, the detectability in radiologic imaging appears limited. MATERIALS AND METHODS: Six patients, who received a cochlear implant between August 2014 and March 2015, were retrospectively analyzed for the detectability of the Med-El Electrode Fixation Clip in postoperative cone beam CT scans. For these patients, we randomly extracted appropriate control group patients without implanted clips (matched pairs). One instructed neuro-radiologist blindly evaluated postoperative radiographs on a visual, descriptive basis of both groups with the main outcome measure of clip detectability. RESULTS: In total, images of 12 patients were evaluated. In five of the six (83%) study group patients, the clip was detected radiologically correct. One patient (17%) was appointed as false negative. All patients (100%) without a clip were correctly identified. DISCUSSION: The electrode fixation clip can be identified, despite its small size, using cone beam CT. Sensitivity and specificity are high. This aspect assumes importance especially in postoperative monitoring, e.g. in cases of revision surgery. Thus, this study contributes to the overall safety in cochlear implant surgery.

Tolerability of sialendoscopy under local anesthesia.

OBJECTIVES: We sought to investigate patients' tolerance of sialendoscopy of the parotid and submandibular glands with local anesthesia. METHODS: In a retrospective case series of 84 adult patients who underwent sialendoscopy with local anesthesia at an academic tertiary referral hospital, we analyzed patients' demographic data, American Society of Anesthesiologists (ASA) status score, perioperative cardiovascular parameters, and results on a 2-question survey. RESULTS: Of the 84 patients, 44 were female and 40 were male (mean age, 48.6 years). The patients had a mean ASA status score of 1.57. On average, 2.16 mL of local anesthetic was used. The mean systolic blood pressure was 137 mm Hg, and the mean diastolic blood pressure was 80 mm Hg. The duration of the procedure showed a significant correlation with the maximum systolic blood pressure (r = 0.35; p = 0.001), the mean systolic blood pressure (r = 0.25; p = 0.02), the maximum diastolic blood pressure (r = 0.37; p = 0.001), and the mean diastolic blood pressure (r = 0.31; p = 0.005). The mean heart rate was 77 beats per minute. The majority of patients considered the procedure to be tolerable. In this series, the indications for conducting sialendoscopy under general anesthesia were procedures of greater invasiveness and complex situations with multiple sialolithiases, difficult anatomic preconditions, or a very long expected operation time. CONCLUSIONS: Sialendoscopy performed with local anesthesia is well tolerated, provided that the patient has a good general health status and the operative procedure is not expected to be complex or long-lasting.

Impact of partial mastoid obliteration on caloric vestibular function in canal wall down mastoidectomy.

OBJECTIVE: To evaluate the influence of our technique of partial mastoid obliteration with autologous bone pâté covered by cartilage plates on vestibular stimulation. METHODS: Twenty-six patients who were treated for recurrent chronic otitis media by revision canal wall down tympanomastoidectomy and subsequent partial obliteration were invited for follow-up; 18 patients agreed to a complete follow-up including vestibular testing. Patients received questionnaires for evaluating preoperative and postoperative symptoms associated with vertigo. Examination comprised otomicroscopy, pure-tone audiometry, and caloric testing. RESULTS: Mean follow-up was 6 years. Before surgery, 54% of the patients reported vertigo on caloric stimuli such as wind, water, or suction cleaning of the tympanomastoid cavity. In all patients, these symptoms were suspended after partial mastoid obliteration. The postoperative obliterated cavity volume averaged 3.1 ml. All cavities after surgery appeared completely epithelialized and dry. The postoperative caloric vestibular tests revealed an average nystagmus count of 46 beats per minute compared with 72 beats before surgery. Thus, the partial mastoid cavity obliteration led to a mean nystagmus reduction of 36% in our study group. CONCLUSION: Our technique of partially obliterating tympanomastoid cavities with autologous bone pâté being covered by cartilage plates results in small cavities with complete epithelialization of all surfaces. Furthermore, obliteration of mastoid cavities confers protection to the labyrinthine organ, thereby reducing postoperative vertigo on caloric stimulation.

Cervical hemorrhage due to spontaneous rupture of the superior thyroid artery: Case report and review of the literature.

BACKGROUND: Beneath the different reasons for cervical masses, a spontaneous hemorrhage presents a rare and life-threatening condition. METHODS AND RESULTS: We present the rare case of a 62-year-old man who was presented with a dramatically enlarging cervical mass causing respiratory distress because of upper airway compression. An endotracheal intubation was lifesaving and avoided tracheotomy. A CT scan revealed a hematoma in the region of the left external carotid artery. An emergency angiography embolized a ruptured branch of the superior thyroid artery and surgery evacuated the hematoma. We discuss the rarity of the condition, reasons for a spontaneous rupture of the artery, and the diagnostic and treatment strategy. In addition, we review the literature on spontaneous thyroid artery hemorrhages, which, up to now, have been described only for the inferior thyroid artery. CONCLUSION: We conclude that the optimal management for cases of cervical hematoma is intubation, diagnosis, and angiography before surgery.

Cartilage plate tympanoplasty.

OBJECTIVES: The purpose of this work was to report our modified cartilage plate tympanoplasty technique ("tulip leaves") and to analyze its clinical outcome in primary and recurrent cases of chronic otitis media with and without cholesteatoma. STUDY DESIGN: Clinical retrospective study. METHODS: Patients being operated on with this technique at the University Department of Otorhinolaryngology, Dresden, Germany, between 1993 and 2001 were invited for survey, otomicroscopy, and pure-tone audiometry in 2003. Patients' charts were used to draw necessary conclusions. RESULTS: A total of 39 patients who were treated with this technique after canal wall down tympanomastoidectomy and cavity obliteration were included in this long-term analysis after a median follow-up of 6 years. Seventeen patients (44%) experienced chronic otitis media with cholesteatoma, whereas 22 (56%) of them had a diagnosis of chronic otitis media without cholesteatoma. At the time of examination, all patients displayed a closed tympanic membrane. However, retractions were observed in 19 patients (48%). One patient required (3%) revision surgery for recurrent cholesteatoma due to prosthesis extrusion during the study period. CONCLUSION: On the basis of this study, we recommend the tuliplike arrangement of thin but large auricular cartilage slices for the reconstruction of tympanic membrane defects in high-risk ears. This combination proved its high stability and long-lasting vitality in our long-term study. These characteristics are crucial for permanent disease removal and for reducing the risk of recurrent pathologic abnormality.

Carbon dioxide laser endoscopic diverticulotomy for Zenker's diverticulum: results and complications in a consecutive series of 40 patients.

BACKGROUND: Numerous studies regarding CO2 laser endoscopic diverticulotomy for the treatment of Zenker's diverticulum exist. They show differences in complications, hospitalization time and postoperative treatment. OBJECTIVES: We report our experiences and work out recommendations for postoperative care. METHODS: All charts of patients who were treated for Zenker's diverticulum at the University Department of Otolaryngology, Cologne, Germany, between 1983 and 2003, were reviewed retrospectively. RESULTS: The median age was 58 years. Postoperatively, patients were fed nonorally and received postoperative antibiotic treatment. One patient developed mediastinitis and 3 patients a rise in body temperature. A control radiography disclosed pharyngeal leakages in 3 patients. Overall morbidity averaged 10%. CONCLUSION: To avoid severe complications we recommend postoperative antibiotic treatment and parenteral feeding. In comparison to the stapler-assisted technique the use of the CO2 laser allows a good view at the diverticular wall throughout the procedure. The transcervical technique should be reserved for cases of anatomic abnormalities or for complicated revision surgeries.

Safety and efficacy of botulinum toxin therapy in otorhinolaryngology: experience from 1,000 treatments.

OBJECTIVES: The objective of this study was to analyze the safety and efficacy of botulinum toxin (BTX) therapy in a series of 1,000 treatments on 261 consecutive patients at the University Department of Otorhinolaryngology-Head and Neck Surgery, Cologne, Germany. STUDY DESIGN/METHODS: A prospective computer database was analyzed, and all patient charts were reviewed retrospectively. In doing so, the main focus was put on patient characteristics, treatment methods, efficacy, unwanted side effects, and reinjection rate. RESULTS: A total of 16 different indications were treated with BTX belonging to the categories of focal dystonias, focal hyperhidrotic syndromes, and cosmetic dermatology. The overall morbidity was 1.3%, exclusively consisting of minor side effects. These were all reversible and mostly caused by paralysis of adjacent musculature. We did not observe any severe complications. Three (1.2%) patients developed a secondary nonresponse to BTX type A (BTX-A). Their treatment was continued with BTX type B. In 2.8% of treatments, patients thought the clinical effect was weak and returned for reinjection within 4 weeks after the first treatment. CONCLUSION: The experience from the largest patient series known confirms that BTX-A injections are the therapy of choice for many forms of focal hyperhidrotic syndromes, focal dystonia, and hyperfunctional lines. It is an effective and safe treatment with only minor side effects. For optimal individual results, a thorough documentation of each treatment is necessary. Dosages should be as low as possible to reduce the probability of a patient developing a secondary nonresponse.

Estradiol, tamoxifen and ICI 182,780 alter alpha3 and beta1 integrin expression and laminin-1 adhesion in oral squamous cell carcinoma cell cultures.

Adhesion molecules such as integrins and extracellular matrix proteins like laminins have been identified to play an important role in cell proliferation, migration and invasion by regulating cell-extracellular matrix interaction in various cancers including oral squamous cell carcinoma (OSCC). In this study, the effect of estradiol (E2), and the E2 antagonists tamoxifen (TAM) and ICI 182,780 (ICI) on the expression of integrins and adhesion to laminin-1 in different OSCC in vitro models was analyzed. TAM and ICI inhibited growth in all OSCC cell lines. Dependent on estrogen receptor (ER) status E2 displayed a significant influence on growth after long-term administration. ICI reduced laminin-1 adhesion in all cell lines. beta1 Integrin transcription is reduced with TAM and E2 and alpha3 cell surface expression with TAM. This study shows that OSCC is estrogen and SERM sensitive and that these compounds can modulate cell-matrix interaction in part by modulating integrin expression and translation. The investigation also confirms that growth is significantly influenced by these adjuvant therapeutics. These data suggest that a greater understanding of basic biology and mechanisms of the ER and its ligands in oral squamous cells is needed to elucidate the use of specific pharmacological agents as therapeutics of anti-tumorigenic pathways.

The influence of tamoxifen on growth behavior and cell-cell adhesion in OSCC in vitro.

The aim of this study was to evaluate the influence of tamoxifen on the growth and aggregation behavior, focusing on the expression pattern of E-cadherin and beta-catenin, in oral squamous cell carcinoma (OSCC) in vitro. Oral squamous cancer cell lines (UM-SCC-14A, UM-SCC-14B and UM-SCC-14C) were treated with various concentrations of tamoxifen. Growth and aggregation behavior as well as the protein expression and its changes were analysed. All cell lines are estrogen receptor (ER) positive. Tamoxifen induced a significant growth inhibition and induced the ability to form cell aggregates. This phenomena was not accompanied by a change in E-cadherin or beta-catenin expression or due to transcriptional changes. beta-catenin showed isolated membrane staining and nuclear distribution in all cell lines. A defective Ecadherin/beta-catenin complex was seen in UM-SCC-14C with no restoration through tamoxifen treatment. The cell-cell formation is increased in all cell lines without any alterations in the functional and quantitative status of E-cadherin or beta-catenin, indicating that novel cell-cell adhesion complexes not involving the classical E-cadherin/beta-catenin influence cell growth and intercellular adhesion in OSCC.