Management and outcome of vagus nerve stimulator implantation: experience of an otolaryngeal/neuropediatric cooperation.

OBJECTIVE: Vagus nerve stimulator (VNS) implantation is an established therapy for pharmacoresistant epilepsy that is not amenable to curative epilepsy surgery. Historically, VNS implantation has been performed by neurosurgeons, but otolaryngologist involvement is increasingly common. In this retrospective study, we aimed to evaluate the efficacy and safety of VNS implantation in children and adolescents from the otolaryngologists' perspective. METHODS: This study included children and adolescents who had undergone VNS implantation at the study center between 2014 and 2018. Patient files were analyzed with regards to the durations of device implantation and hospitalization, postoperative complications, and clinical outcome, including seizure frequency, clinical global impression of improvement (CGI-I) score, and quality of life (QoL). RESULTS: A total of 73 children underwent VNS surgery. The median age at implantation was 9.3 ± 4.6 years, and median epilepsy duration before VNS surgery was 6 ± 4 years. Lennox-Gastaut syndrome was the most common syndrome diagnosis (62.3%), and structural abnormalities (49.3%) the most frequent etiology. Operation times ranged from 30 to 200 min, and median postoperative hospitalization length was 2 ± 0.9 days. No complications occurred, except for four revisions and two explantations due to local infections (2.7%). Among our patients, 76.7% were responders (≥ 50% reduction in seizure frequency), 72.1% showed improved CGI-I scores, and 18.6-60.5% exhibited considerable improvements in the QoL categories energy, emotional health, and cognitive functions. CONCLUSION: Our results indicate that VNS implantation is a highly effective and safe treatment option for children and adolescents with AED-refractory epilepsies who are not candidates for curative epilepsy surgery.

Towards a consensus on a hearing preservation classification system.

CONCLUSION: The comprehensive Hearing Preservation classification system presented in this paper is suitable for use for all cochlear implant users with measurable pre-operative residual hearing. If adopted as a universal reporting standard, as it was designed to be, it should prove highly beneficial by enabling future studies to quickly and easily compare the results of previous studies and meta-analyze their data. OBJECTIVES: To develop a comprehensive Hearing Preservation classification system suitable for use for all cochlear implant users with measurable pre-operative residual hearing. METHODS: The HEARRING group discussed and reviewed a number of different propositions of a HP classification systems and reviewed critical appraisals to develop a qualitative system in accordance with the prerequisites. RESULTS: The Hearing Preservation Classification System proposed herein fulfills the following necessary criteria: 1) classification is independent from users' initial hearing, 2) it is appropriate for all cochlear implant users with measurable pre-operative residual hearing, 3) it covers the whole range of pure tone average from 0 to 120 dB; 4) it is easy to use and easy to understand.

Music perception in electric acoustic stimulation users as assessed by the Mu.S.I.C. test.

AIMS: This study compared the music perception abilities of 13 electric acoustic stimulation (EAS) users with two control groups: unilateral cochlear implant (CI) users and normal-hearing (NH) listeners. METHODS: Groups were matched according to age and musical experience before hearing loss (HL) and tested using the Musical Sounds in Cochlear Implants (Mu.S.I.C.) test. RESULTS: No difference was found on rhythm perception, chord discrimination, dissonance rating, and emotion rating subtest performance between groups. Mean frequency discrimination scores were significantly better in EAS participants than in CI participants and not significantly worse than in NH participants. However, the EAS and CI groups scored similarly (significantly worse than NH participants) on both instrument detection and identification. Results for EAS participants were not significantly worse when the hearing aid component was removed. Frequency of listening to music before HL was negatively correlated with EAS participants' frequency discrimination scores, though singing and playing an instrument appeared to have no effect. EAS participants who indicated many reasons for listening to music and who listen to many genres after implantation scored higher on instrument detection and instrument identification. Better results on these two subtests were correlated with EAS participants' better postoperative auditory thresholds at 250 and 500 Hz. CONCLUSIONS: Though EAS participants performed better on music perception testing (though not timbre-based tasks) than CI participants, their scores did not reach the level of NH participants. This indicates that acoustic hearing in the low frequencies is helpful for music perception, though not the only important factor.

[Navigation-assisted sonography for soft tissues in the head and neck region]. / Navigationsunterstützte Weichteilsonographie für den Kopf-Hals-Bereich.

BACKGROUND: In soft tissue surgery of the head and neck region tissue shifts limit the usefulness of conventional CT/MRI-based navigation procedures. Furthermore, changes caused by invasive measures cannot be visualized. METHODS: A novel navigation device for sonography of soft tissues was developed. This consists of a navigated ultrasound scanner, a navigated surgical instrument, and a personal computer with custom-made software. Its use makes an additional visualization by means of CT or MRI dispensable. RESULTS: The system deviation (three-dimensional error) of this newly developed prototype was less than 1 mm. The practical application in a model setup showed good handling properties of the system. Orientation and approach of the surgical instrument to the sonographically visualized target structure were rapid and accurate. CONCLUSION: This new navigation system does not require additional CT or MRI images. The navigated ultrasound probe shows tissue changes in real time. This navigation system is especially suitable for invasive procedures in soft tissues.

Navigation-supported and sonographically-controlled fine-needle puncture in soft tissues of the neck.

In surgery, sonography has been a well-accepted means of orientation for years. The immediate vicinity of many vital structures in the head and neck region calls for a very exact visualization of the surgical instrument in the 2-D ultrasonic picture. We report on the development of a new method for navigation-supported and sonographically-controlled fine-needle puncture in soft tissues of the neck. Our system comprises a navigated ultrasound probe, a navigated fine-puncture needle and a coordinate sensor. A personal computer with specially-developed software assists calibration and surgical application. The applicability test for the system is described. In vitro, a model lymph node of 9 mm in diameter had been hit. It is shown that the target structure can be aimed at very precisely by the navigated puncture needle. An accuracy of 97% and a specificity of 99% could be demonstrated. The development of a very precise and easy-to-handle method for navigation-supported fine-needle puncture in the neck region is presented. The outstanding advantage of this method is that no rigid reference gadget fixed to the patient's body is necessary. That makes this method very suitable for surgery in the neck region. Contrary to other sonographically-supported navigation methods in the head and neck region, preoperative imaging (CT or MRT) is dispensable.

Pre-treatment haemoglobin level predicts response and survival after TPF induction polychemotherapy in advanced head and neck cancer patients.

OBJECTIVE: To investigate the prognostic value of the pre-treatment haemoglobin level in patients with advanced squamous cell head and neck cancer treated with induction polychemotherapy. DESIGN: Seventy-two patients with advanced squamous cell head and neck cancer received primary combination chemotherapy consisting of docetaxel 75 mg/m(2) on day 1, cisplatin 100 mg/m(2) on day 1, and 5-fluorouracil (5-FU) 1000 mg/m(2)/day on days 1-4 (total dose 4000 mg/m(2)), repeated on days 1, 22 and 43 followed by chemoradiation. The data collected included pre-treatment haemoglobin, response to treatment, disease-free and overall survival. RESULTS: The pre-treatment haemoglobin level was found to be a significant predictor of response to induction chemotherapy (P = 0.01) and an independent predictor of overall survival [hazard ratio (HR) 0.77, 95% confidence interval (CI) 0.58-1.03, P = 0.0001] and disease free survival (HR 2.09, 95% CI 1.41-3.09, P = 0.0001). Furthermore N-stage was found to be a significant prognostic factor of overall survival (HR 9.24, 95% CI 6.90-21.34, P = 0.005). The Eastern Cooperative Oncology Group performance status scale was also found to be significant for disease free survival (HR 7.66, 95% CI 2.61-22.46, P = 0.003). CONCLUSION: In patients with advanced squamous cell head and neck cancer, the haemoglobin level prior to induction chemotherapy is significantly related to outcome including response and survival.

Evaluating cochlear implant trauma to the scala vestibuli.

OBJECTIVES: Placement of cochlear implant electrodes into the scala vestibuli may be intentional, e.g. in case of blocked scala tympani or unintentional as a result of trauma to the basilar membrane or erroneous location of the cochieostomy. The aim of this study was to evaluate the morphological consequences and cochlear trauma after implantation of different cochlear implant electrode arrays in the scala vestibuli. DESIGN: Human temporal bone study with histological and radiological evaluation. SETTING: Twelve human cadaver temporal bones were implanted with different cochlear implant electrodes. Implanted bones were processed using a special method to section undecalcified bone. MAIN OUTCOME MEASURES: Cochlear trauma and intracochlear positions. RESULTS: All implanted electrodes were implanted into the scala vestibuli using a special approach that allows direct scala vestibuli insertions. Fractures of the osseous spiral lamina were evaluated in some bones in the basal cochlear regions. In most electrodes, delicate structures of the organ of Corti were left intact, however, Reissner's membrane was destroyed in all specimens and the electrode lay upon the tectorial membrane. In some bones the organ of Corti was destroyed. CONCLUSIONS: Scala vestibuli insertions did not cause severe trauma to osseous or neural structures, thus preserving the basis for electrostimulation of the cochlea. However, destruction of Reissner's membrane and impact on the Organ of Corti can be assumed to destroy residual hearing.

Carcinomas unresponsive to either cisplatinum or anti-EGFR therapy can be growth inhibited by combination therapy of both agents.

BACKGROUND: Previously we demonstrated that the antitumor efficacy of monoclonal antibodies against the EGFR (epidermal growth factor receptor) of human tumor xenografts mainly depends on the EGFR content of tumors rather than on the tumors' entity. In this study we wanted to elucidate whether the described cumulative effect of cisplatin and Anti-EGFR therapy also depends on the EGFR expression. MATERIALS AND METHODS: Xenotransplanted carcinomas with different EGFR levels were treated with monoclonal antibodies against the EGFR (EMD 72000 and EMD 55900), cisplatinum and a combination of both. RESULTS: Each monoclonal antibody alone led to an EGFR-dependent significant tumor growth reduction. Cisplatinum alone had no growth inhibitory effects on tumors with high content in contrast to those with low EGFR content. The combination of antibodies with cisplatinum resulted in an EGFR-independent tumor growth inhibition which was stronger than observed in the case of monotherapy. DISCUSSION: The obtained results may address upcoming phase I/II trials to use Anti-EGFR/Cisplatinum therapy regardless of the EGFR content of tumors.

Intraoperative electromyography for identification of the trapezius muscle innervation: clinical proof of a new anatomical concept.

OBJECTIVE/HYPOTHESIS: There is still considerable controversy among surgeons on trapezius muscle innervation. In addition, the rate of unexpected postoperative trapezius pareses is unacceptably high. Recent anatomical findings might answer most of the questions. The objective of the present study was to clinically prove the recent anatomical findings, especially the concept of the innervation of the descending part of the trapezius muscle. STUDY DESIGN: Intraoperative electromyography of the spinal accessory nerve and its branches in the posterior triangle of the neck. SETTING: Intraoperative electromyography was performed during 17 modified radical neck dissections on 14 patients of both sexes ranging in age from 44 to 68 years (mean age, 56 y). Potentials were registered through pairs of needle electrodes placed in each of the three parts of the trapezius muscle. Intraoperatively, the spinal accessory nerve and its fine cranial branch passing toward the descending part of the muscle were identified and stimulated in the posterior triangle of the neck.RESULTS Stimulation of the fine cranial branch of the spinal accessory nerve led to a clearly visible and recordable contraction in the descending part of the trapezius muscle in all patients. Stimulation of the main trunk of the spinal accessory nerve in the posterior triangle of the neck distal to the above-mentioned branching led to a clearly visible and recordable contraction in the transverse and ascending parts of the muscle. CONCLUSIONS: The results strongly support recent anatomical findings showing that, functionally, the most important descending part of the trapezius muscle is innervated by a fine single branch arising from the spinal accessory nerve in the posterior triangle of the neck. This may help to prevent more patients undergoing modified radical neck dissections from shoulder-arm syndrome.

CT and MR imaging of acquired abnormalities of the inner ear and cerebellopontine angle.

INTRODUCTION: Several entities of acquired lesions may affect the inner ear and cerebellopontine angle. The imaging of these lesions depends on the clinical history, and should be adapted to the lesion searched for and suspected by the otolaryngologist. In this paper, the modality of CT and MR imaging which is suited to delineate the acquired lesions of this region will be presented. MATERIALS AND METHODS: CT and/or MR imaging of the inner ear and cerebellopontine angle was performed in all cases in which an acquired lesion of this region was suspected by the otolaryngologist. CT was performed in the axial and coronal plane with the use of a high-resolution bone-window-level-setting. MRI was performed in the axial plane using high-resolution 3D T2-weighted fast spin echo sequences and 3D T1-weighted gradient echo sequences before and after the i.v. application of gadopentate dimeglumine. The obtained images were evaluated for the depiction of the acquired lesions. RESULTS: CT best depicted osseous lesions such as traumatic affections or lesions leading to ossification of the inner ear. Tumorous lesions were delineated in those cases in which they yielded to bony changes. Inflammatory or tumorous lesions not yielding to bony changes or intralabyrintine calicifications were not depicted. MRI delineated very well all lesions leading to soft tissue changes, and moderately depicted traumatic changes yielding to less severe fractures affecting the investigated region. CONCLUSION: CT and MR imaging are suited differently to delineate the acquired lesions of the inner ear and cerebellopontine angle. CT is excellently suited to depict osseous lesions, while MRI is excellently suited to delineate lesions affecting the soft tissue structures. These two imaging modalities should be used depending on the clinical question, and are supposed to be complementary methods.

Clinical application of magnetic resonance imaging in 30 cochlear implant patients.

OBJECTIVE: The goal of this investigation was to provide evidence that magnetic resonance imaging (MRI) can be performed safely and effectively on cochlear implant patients who require diagnosis of additional diseases. STUDY DESIGN: A retrospective study was performed over 5 years. In a total of 300 patients with cochlear implants at the authors' center, MRI was performed whenever it was medically indicated. SETTING: All patients underwent scanning in a Philips Gyroscan T10-NT MRI machine, using commercially available Powertrac 3000 software. PATIENTS: All patients with cochlear implants for whom MRI was indicated (n = 30) were included in this study. They had a wide variety of conditions necessitating MRI, including cervical discus prolapse, hypophyseal adenoma, epipharynx carcinoma, knee degeneration, parotid tumor, and preoperative evaluation for reimplantation and bilateral implantation. RESULTS: No adverse effects from the MRI were reported by any of the patients. The cochlear implants all retained their function. All images were of diagnostic value. Because of the MRI, the patients did not need to undergo additional, more invasive and expensive diagnostic procedures. Examples of MRI images from 5 patients are shown. CONCLUSIONS: MRI on cochlear implant patients, using the Med El Combi 40 and Nucleus mini 22 series at 1 Tesla, can be a safe procedure. Removal of any magnet is not necessary.

Perimodiolar electrodes in cochlear implant surgery.

Perimodiolar-positioned cochlear implant electrodes have been developed in order to bring the electrode contacts as close as possible to the spiral ganglion cells, which are the target of electrostimulation. This results in lower electrical thresholds, higher dynamic ranges and less channel interaction when compared with normal implant electrodes which are usually located peripherally within the scala tympani. In this study we evaluated 4 different types of perimodiolar electrode: the Clarion Preformed electrode, the Clarion Preformed electrode with positioner, the Nucleus Contour electrode and the Med-El Perimodiolar Combi 40 electrode. These devices require different approaches to achieve a perimodiolar electrode position. The electrodes were inserted in fresh human temporal bones. After processing these bones with the electrodes in situ by employing a sawing, grinding and polishing technique, the inner ear structures as well as the electrode positions could be evaluated in detail. All electrode types studied had a more or less perimodiolar position; however, each type produced a certain amount of trauma to cochlear structures which is discussed in relation to mechanical properties. Further human temporal bone studies with improved perimodiolar cochlear implant electrodes are necessary in order to find an optimized type of electrode.

Hearing performance in noise of cochlear implant patients versus severely-profoundly hearing-impaired patients with hearing aids.

It is possible for most post-lingually deaf patients to attain significant open speech recognition following cochlear implantation. In contrast, many severely-profoundly sensorineural hearing-impaired patients receive no benefit from their hearing aids, especially in situations with background noise. The aim of the study was to evaluate the speech recognition ability in quiet and in noise of post-lingually deaf adults implanted with Combi 40/40+ cochlear implants versus severely-profoundly sensorineural hearing-impaired patients fitted with hearing aids. For this purpose, we tested two groups of patients: one that had received cochlear implants (n=22) and a group of subjects with severe-profound sensorineural hearing impairment, fitted with hearing aids (n = 15). All of the patients were tested using the Hochmaier, Schultz, and Moser Discrimination Test in quiet and noise. The results of the study demonstrate that most of our cochlear implant patients received a substantial benefit from their implant, achieving scores of 70 to 100 per cent (mean, 90 per cent) for the numbers test and 10 to 72 per cent (mean, 43 per cent) for the monosyllable test 1 year after implantation. Even in situations with background noise, scores of 1 to 99 per cent (mean, 45.65 per cent) for a signal to noise ratio (SNR) of +15 dB 1 year following the implantation improved to 7 to 95 per cent (mean, 50.7 per cent) at 2 years and 8 to 99 per cent (mean, 60 per cent) at 3 years after implantation. These results are significantly (p<0.04) superior to the hearing aid patients' scores of 1 to 64.2 per cent (mean, 26.7 per cent) for a SNR of 15 dB. The results of the present study may have clinical implications in regard to selection of candidates for cochlear implantation.

Comparison of speech recognition with different speech coding strategies (SPEAK, CIS, and ACE) and their relationship to telemetric measures of compound action potentials in the nucleus CI 24M cochlear implant system.

Speech understanding and subjective preference for three different speech coding strategies (spectral peak coding [SPEAK], continuous interleaved sampling [CIS], and advanced combination encoders [ACE]) were investigated in 11 post-lingually deaf adult subjects, using the Nucleus CI 24M cochlear implant system. Subjects were randomly assigned to two groups in a balanced crossover study design. The first group was initially fitted with SPEAK and the second group with CIS. The remaining strategies were tested sequentially over 8 to 10 weeks with systematic variations of number of channels and rate of stimulation. Following a further interval of 3 months, during which subjects were allowed to listen with their preferred strategy, they were tested again with all three strategies. Compound action potentials (CAPs) were recorded using neural response telemetry. Input/output functions in relation to increasing stimulus levels and inter-stimulus intervals between masker and probe were established to assess the physiological status of the cochlear nerve. Objective results and subjective rating showed significant differences in favour of the ACE strategy. Ten of the 11 subjects preferred the ACE strategy at the end of the study. The estimate of the refractory period based on the inter-stimulus interval correlated significantly with the overall performance with all three strategies, but CAP measures could not be related to individual preference of strategy or differences in performance between strategies. Based on these results, the ACE strategy can be recommended as an initial choice specifically for the Nucleus CI 24M cochlear implant system. Nevertheless, access to the other strategies may help to increase performance in individual patients.

The sternocleidomastoid flap--its indications and limitations.

HYPOTHESIS: The sternocleidomastoid (SCM) flap seems to be a practicable but underestimated flap for reconstructive and plastic surgery of the head and neck. OBJECTIVES: To determine in which situations the SCM flap may represent a reliable alternative to other flaps used in head and neck surgery. STUDY DESIGN: Meta-analysis of the complete literature on the SCM flap. SETTING: All literature found dealing with the SCM flap was reviewed, with special emphasis placed on the indications and success rates reported. The data presented are compared with our own morphologic findings and their putative clinical implications. RESULTS: Four types of SCM flap have been described: the muscle flap, the myocutaneous flap, the myoperiosteal flap, and the myosseus or osteomuscular flap. The SCM flap was either superiorly or inferiorly based. The SCM muscle flap was used in a total of 72 patients with only 1 major complication and 7 minor complications. The complication rate, therefore, is 11%. The applications of the muscle flap involved prevention of Frey's syndrome, closure of orocutaneous fistulae and soft tissue deficiencies, closure of pharyngocutaneous and cervical esophageal fistulae, and reconstruction of the tongue. Furthermore, Conley reported on the use of the SCM muscle flap in a group of 30 patients to reanimate the face, reconstruct oral cavity defects, protect the carotid and innominate artery, and even to aid shoulder elevation after poliomyelitis. The SCM myocutaneous flap seems to be the most common application, with a total of 138 patients. All in all, a total of 29 complications (21%) was reported, with partial skin necrosis by far the most frequent. Total failure of the flap has been described in 10 patients (7%). The SCM myocutaneous flap was used for closure of defects of the mouth as well as oro-, pharyngo-, and tracheocutaneous fistulae, facial reconstruction, reconstruction of mastoid defects, and reconstruction of the laryngotracheal complex in children. The SCM myosseus or osteomuscular flap was reported in 23 patients. Flap necrosis is reported in 1 case (4%). The SCM osteomuscular flap was used to reconstruct defects of the lower jaw in all patients. The SCM myoperiosteal flap was used in a total of 49 patients. The complication rate reported is 6% (3 cases). The myoperiosteal flap was used for reconstruction of the laryngotracheal complex in adults and for esophagopharyngeal reconstruction and fistula repair. CONCLUSIONS: The data presented in previous literature is well correlated with our own morphologic findings. In comparison of the different techniques applied with the assumptions drawn on the basis of our own anatomic findings, it becomes evident that the SCM flap is only a useful tool in limited indications and under certain precautions.

Short-term effect of auditory feedback on fundamental frequency after cochlear implantation.

The present study evaluates the short-term effect of cochlear implantation on the fundamental frequency (FO) of 13 deaf patients. All patients were provided with the Combi 40+ cochlear implant. Voice recording was made pre- and 3 months post-implantation. The FO was analysed using X-Tools software. The results showed that 38 per cent of our subjects had a statistically significant decrease of their mean F0 (p=0.001) at 3 months following implantation. It was also observed that the patients tended to have a lower F0 postoperatively approaching the normal range of F0. A large variability in F0 was noticed among the deaf subjects but no correlation with the duration of deafness was seen. There was also no correlation between speech recognition and speech production.

[Rehabilitation of hearing-impaired patients with cochlear implants: a review]. / Rehabilitation Hörgeschädigter mit Cochlear-Implantaten--eine Ubersicht.

The aim of this paper is to provide an overview of the cochlear implant. The history of this entity is traced from the early development of implants, involving the stimulation of the hearing nerve, up to the currently available standard multichannel implants. The physiological background is also elucidated. A cochlear implant consists of an implantable portion which lies within the ear, and of parts that are worn externally on the body. Differences between the first implants and those now in use are as follows: transcutaneous information and energy transmission, the position of the electrode in the ear, and the configuration of the electrode. Differences between the currently available implants mainly concern the number of electrodes, speech coding strategies and the mode of electrode stimulation. Almost all of the most recent implants are equipped with electrodes that are implanted in the tympanic scale of the cochlea.