Auditory Brainstem Implants-Hearing Restoration in Congenitally Deaf Children.

BACKGROUND: Children who are born deaf can learn to hear and to speak with the aid of a cochlear implant (CI). If the implantation of a CI is not possible for anatomical reasons, an auditory brainstem implant (ABI) is the only surgical option for auditory rehabilitation. It is estimated that about 5 to 45 children could potentially benefit from this treatment in Germany each year. In this article, we present and discuss the current state of the scientific evidence. METHODS: The PubMed and Embase databases were searched for relevant publications from 2010 onward. 15 articles reporting at least 10 cases with at least one year of auditory follow-up were included in the analysis. The results, including CAP ("categories of auditory performance") scores on a scale of 0 to 7, are presented and compared with the authors' own findings in a series of 38 patients. RESULTS: All of the publications show that children who do not suffer from impairments of other kinds hear significantly better with an ABI than those with additional handicaps. Early implantation is advantageous, under the age of three years if possible. The results vary widely across publications and from patient to patient. The mean CAP score in all publications is 3.57 (standard deviation [SD], 1.04). 38.24% of the patients (SD 18.68) achieved the ability to understand spoken language (CAP ≥= 5), more specifically, the ability to communicate in everyday life without lip reading, in person and some even succeed in conversing over the telephone. CONCLUSION: ABI is a safe and effective treatment for sensorineural deafness in congenitally deaf children who cannot be treated with a cochlear implant. In particular, children without any other impairments have a good chance of developing the ability to understand spoken language, especially if the implantation is performed early.

[CLIPPERS syndrome - a disorder with many faces- a case report]. / CLIPPERS-Syndrom: Eine Erkrankung mit vielen Gesichtern ­ ein Fallbericht.

The CLIPPERS syndrome is a chronic, inflammatory disorder of the central nervous system of unknown etiology, which was first described in 2010 by Pittock and colleagues. It is characterized by typical magnetic resonance imaging (MRI) changes with lesions mainly in the brainstem, a perivascular, lymphohistiocytic inflammatory process and significant improvement under glucocorticoid therapy. Here we describe the case of a 40-year-old male who presented initially with typical clinical and radiological signs of CLIPPERS syndrome and who achieved complete remission under immunosuppressive therapy. Two years later, he presented with severe headaches. The MRI showed a reappearance of the lesion in the cerebellum, but now with a confluent character. The first brain biopsy showed lymphoproliferation. A second brain biopsy could finally confirm the suspected diagnosis of a primary CNS lymphoma.

Three-dimensional imaging of the human internal acoustic canal and arachnoid cistern: a synchrotron study with clinical implications.

A thorough knowledge of the gross and micro-anatomy of the human internal acoustic canal (IAC) is essential in vestibular schwannoma removal, cochlear implantation (CI) surgery, vestibular nerve section, and decompression procedures. Here, we analyzed the acoustic-facial cistern of the human IAC, including nerves and anastomoses using synchrotron phase contrast imaging (SR-PCI). A total of 26 fresh human temporal bones underwent SR-PCI. Data were processed using volume-rendering software to create three-dimensional (3D) reconstructions allowing soft tissue analyses, orthogonal sectioning, and cropping. A scalar opacity mapping tool was used to enhance tissue surface borders, and anatomical structures were color-labeled for improved 3D comprehension of the soft tissues. SR-PCI reproduced, for the first time, the variable 3D anatomy of the human IAC, including cranial nerve complexes, anastomoses, and arachnoid membrane invagination (acoustic-facial cistern; an extension of the cerebellopontine cistern) in unprocessed, un-decalcified specimens. An unrecognized system of arachnoid pillars and trabeculae was found to extend between the arachnoid and cranial nerves. We confirmed earlier findings that intra-meatal vestibular schwannoma may grow unseparated from adjacent nerves without duplication of the arachnoid layers. The arachnoid pillars may support and stabilize cranial nerves in the IAC and could also play a role in local fluid hydrodynamics.

Postoperative Cochlear Obliteration after Retrosigmoid Approach in Patients with Vestibular Schwannoma.

Objective Vestibular schwannomas (VSNs) account for the vast majority of lesions located in the cerebellopontine angle (CPA). The goals of VSN surgery are possible total tumor removal, intact facial nerve function, and preservation of cochlear nerve function. In cases of pre- or postoperative deafness, restoration of hearing with auditory brainstem implant (ABI) or cochlear implant (CI) is a promising treatment option with normally better results in CI than in ABI. The aim of this retrospective study is to evaluate cochlear ossification or obliteration secondary to a retrosigmoid approach, which is important for later CI, especially in single-sided deafness. Materials and Methods We retrospectively reviewed data from our suboccipital retrosigmoid operation database for the period from January 2008 to February 2015. A total of 65 patients with VSN could be analyzed retrospectively. The patient's data (age, gender, side of operation, tumor entities, and the duration of follow-up) were evaluated. The most recent T2-weigted MRI exams were taken into account for the evaluation of cochlea. To compare left and right sides, the coronal reformatted images were reconstructed in a symmetrical way. Results Twenty-two out of 65 (33%) patients had cochlear obliteration in our survey. The cochlear obliteration was more common in females (44 vs. 20% in males). The median follow-up was 28 months. The size and the intrameatal extension of tumors could not be considered as factors influencing the cochlear obliteration rate. According to our survey, 33% of suboccipital approaches manifested cochlear obliteration to some extent. It was more common in females. The intrameatal extension of tumors played statistically no role in the occurrence of postoperative cochlear obliteration. Whether the prohibition of cochlear ossification can be best achieved by retrosigmoid approaches, compared to other approaches to the CPA, or not could be a subject of future studies.

German validation of Quality of Life after Brain Injury (QOLIBRI) assessment and associated factors.

The consequences of traumatic brain injury (TBI) for health-related quality of life (HRQoL) are still poorly understood, and no TBI-specific instrument has hitherto been available. This paper describes in detail the psychometrics and validity of the German version of an internationally developed, self-rated HRQoL tool after TBI-the QOLIBRI (Quality of Life after Brain Injury). Factors associated with HRQoL, such as the impact of cognitive status and awareness, are specifically reported. One-hundred seventy-two participants after TBI were recruited from the records of acute clinics, most of whom having a Glasgow Coma Scale (GCS) 24-hour worst score and a Glasgow Outcome Scale (GOSE) score. Participants had severe (24%), moderate (11%) and mild (56%) injuries as assessed on the GCS, 3 months to 15 years post-injury. The QOLIBRI uses 37 items to measure "satisfaction" in the areas of "Cognition", "Self", "Daily Life and Autonomy", and "Social Relationships", and "feeling bothered" by "Emotions"and "Physical Problems". The scales meet standard psychometric criteria (α = .84 to .96; intra-class correlation-ICC = .72 to .91). ICCs (0.68 to 0.90) and αs (.83 to .96) were also good in a subgroup of participants with lower cognitive performance. The six-subscale structure of the international sample was reproduced for the German version using confirmatory factor analyses and Rasch analysis. Scale validity was supported by systematic relationships observed between the QOLIBRI and the GOSE, Patient Competency Rating Scale for Neurorehabilitation (PCRS-NR), Hospital Anxiety and Depression Scale (HADS), Profile of Mood States (POMS), Short Form 36 (SF-36), and Satisfaction with Life Scale (SWLS). The German QOLIBRI contains novel information not provided by other currently available measures and has good psychometric criteria. It is potentially useful for clinicians and researchers, in post-acute and rehabilitation studies, on a group and individual level.

New outcomes with auditory brainstem implants in NF2 patients.

OBJECTIVE: To determine factors related to high levels of speech recognition in patients with the auditory brainstem implant (ABI). STUDY DESIGN: Retrospective case review. SETTING: International multicenter data from hospitals and tertiary referral facilities. PATIENTS: Patients with neurofibromatosis type 2 (NF2) and bilateral vestibular schwannomas. INTERVENTION: ABIs were placed after the removal of vestibular schwannomas. MAIN OUTCOME MEASURES: Demographic and surgical data were collected from 26 patients with ABIs who achieved scores of better than 30% correct identification of sentences presented in quiet listening conditions and without lipreading cues. RESULTS: Scores better than 30% speech recognition of standard sentence test materials (HINT or equivalent) in quiet listening conditions were obtained in 26 of the 84 NF2 patients (31%). ABI speech recognition was correlated with surgical position, length of deafness, the number of distinct pitch electrodes, perceptual levels, and ABI stimulation rate, but not correlated with tumor size, tumor stage, the number of electrodes used, or electrophysiological recordings. This paper presents the consensus opinion from a meeting of surgeons to compare outcomes across ABI surgical centers. CONCLUSIONS: The consensus opinion was that brainstem trauma is a primary factor in the variability of outcomes in NF2 patients. The significant co-factors in outcomes implied that ABI surgery should be accomplished with great care to minimize physical and venous trauma to the brainstem. It is clear that high levels of speech recognition, including high levels of open-set speech recognition, are possible with the ABI even in patients with NF2 and large tumors.

Auditory brainstem implantation improves speech recognition in neurofibromatosis type II patients.

This prospective study aimed to determine speech understanding in neurofibromatosis type II (NF2) patients following implantation of a MED-EL COMBI 40+ auditory brainstem implant (ABI). Patients (n = 32) were enrolled postsurgically. Nonauditory side effects were evaluated at fitting and audiological performance was determined using the Sound Effects Recognition Test (SERT), Monosyllable-Trochee-Polysyllable (MTP) test and open-set sentence tests. Subjective benefits were determined by questionnaire. ABI activation was documented in 27 patients, 2 patients were too ill for testing and 3 patients were without any auditory perception. SERT and MTP outcomes under auditory-only conditions improved significantly between first fitting and 12-month follow-up. Open-set sentence recognition improved from 5% at first fitting to 37% after 12 months. The number of active electrodes had no significant effect on performance. All questionnaire respondents were 'satisfied' to 'very satisfied' with their ABI. An ABI is an effective treatment option in NF2 patients with the potential to provide open-set speech recognition and subjective benefits. To our knowledge, the data presented herein is exceptional in terms of the open-set speech perception achieved in NF2 patients.

Pulsatile tinnitus: imaging and differential diagnosis.

BACKGROUND: Pulsatile tinnitus, unlike idiopathic tinnitus, usually has a specific, identifiable cause. Nonetheless, uncertainty often arises in clinical practice about the findings to be sought and the strategy for work-up. METHODS: Selective literature review and evaluation of our own series of patients. RESULTS: Pulsatile tinnitus can have many causes. No prospective studies on this subject are available to date. Pulsatile tinnitus requires both a functional organ of hearing and a genuine, physical source of sound, which can, under certain conditions, even be objectified by an examiner. Pulsatile tinnitus can be classified by its site of generation as arterial, arteriovenous, or venous. Typical arterial causes are arteriosclerosis, dissection, and fibromuscular dysplasia. Common causes at the arteriovenous junction include arteriovenous fistulae and highly vascularized skull base tumors. Common venous causes are intracranial hypertension and, as predisposing factors, anomalies and normal variants of the basal veins and sinuses. In our own series of patients, pulsatile tinnitus was most often due to highly vascularized tumors of the temporal bone (16%), followed by venous normal variants and anomalies (14%) and vascular stenoses (9%). Dural arteriovenous fistulae, inflammatory hyperemia, and intracranial hypertension were tied for fourth place (8% each). CONCLUSION: The clinical findings and imaging studies must always be evaluated together. Thorough history-taking and clinical examination are the basis for the efficient use of imaging studies to reveal the cause of pulsatile tinnitus.

Imaging of cerebrospinal fluid leaks.

The present article provides an overview of epidemiology, clinical signs and symptoms, imaging techniques and specific imaging findings in cerebrospinal fluid leaks. Imaging protocols are supplemented with practical hints for invasive techniques. Emphasis is on the full scope of imaging findings in traumatic and nontraumatic cranial and spinal leaks.

Bilateral electric stimulation from auditory brainstem implants in a patient with neurofibromatosis type 2.

BACKGROUND: Recent developments in the field of electronic hearing prostheses have allowed for the introduction of auditory brainstem implants in patients with neurofibromatosis type 2. CASE REPORT: Bilateral electric stimulation from 2 sequentially placed auditory brainstem implants was applied in a 27-year-old man with neurofibromatosis type 2. CONCLUSIONS: Results of the present case support further application of bilateral electric stimulation from auditory brainstem implants for patients with neurofibromatosis type 2.

The High Rate CIS Auditory Brainstem Implant for Restoration of Hearing in NF-2 Patients.

AIM: Hearing preservation is one of the major goals of acoustic neuroma surgery. In NF-2 patients, bilateral hearing loss is frequently caused by the disease or results from its treatment. Several implant devices for electrical stimulation of the cochlear nucleus have been developed to restore serviceable hearing in these patients. We report our experience and results using a high rate continuous interleaved sampling (CIS) auditory brainstem implant (ABI). METHODS: Between June 1997 and May 2004, 24 NF-2 patients were managed by our group. In 20 patients an ABI was implanted successfully. The cochlear nucleus was located using anatomical landmarks and E-ABR recordings after resection of the neuroma via a retrosigmoid approach in the semi-sitting position. The 12-channel stimulating electrode array was inserted and fixed in the lateral recess. There were no surgical complications related to implantation apart from pseudomeningo that were managed by lumbar drainage. RESULTS: In one patient the electrode array became dislocated and this necessitated revision surgery which was successful. One patient failed to gain benefit from the implant. Overall, 70% of electrodes were found to be serviceable for auditory stimulation, 5.3% of electrodes were primarily nonauditory, and in 7.8% side effects during stimulation were observed. Lip reading was improved by more than 100% as a result of the additional auditory input. For many patients, comprehension of open speech was restored to a useful level. Almost all patients were able to perceive environmental sounds and tinnitus was masked. CONCLUSIONS: Restoration of hearing using ABIs in NF-2 patients is a safe and promising procedure for those who would otherwise be totally deaf. The high rate CIS speech processing strategy has proven to be very useful and effective in direct cochlear nucleus stimulation.

Accuracy and stability of temperature probes for intracranial application.

Intracranial temperature measurement may play a pivotal role for prognosis and treatment of neurological and neurosurgical patients. For reliable clinical application, accurate temperature readings are therefore necessary. We present an independent in vitro study investigating the accuracy and stability of three temperature probes. Eight Neurovent-P Temp (RN), eight Licox temperature sensors (LT) and eight Neurotrend sensors (NT) were placed into a water bath. The temperature was increased in 3 degrees C increments from 30 to 42 degrees C before (accuracy test day 0) and after (accuracy test day 5) a long-term stability test run at 37 +/- 0.2 degrees C. The accuracy tests revealed deviations of <0.25, <0.2 and >0.4 degrees C for the RN, NT and LT probes, respectively, when compared to the reference measurement by a precision Pt100 temperature measuring instrument. All sensor types showed stable readings over the course of 120 h. The high variability of LT probes was due to a malfunctioning Licox monitor. Excluding these values reduced deviation below 0.21 degrees C the standard deviation at each temperature step was below +/-0.08 (RN, NT) and +/-0.12 (LT), laying within the range provided by the manufacturer (RN, NT: +/-0.1; LT: +/-0.2). In general, RN, NT and LT temperature measurement is reliable, but malfunctioning parts may lead to false interpretation of temperature readings. Therefore, validation of temperature probes to a reference temperature prior to clinical use is recommended.

Transluminal balloon angioplasty improves brain tissue oxygenation and metabolism in severe vasospasm after aneurysmal subarachnoid hemorrhage: case report.

OBJECTIVE AND IMPORTANCE: The effect of transluminal balloon angioplasty on cerebral biochemical monitoring during treatment of severe cerebral vasospasm after subarachnoid hemorrhage (SAH) was investigated. CLINICAL PRESENTATION: In a 36-year-old man, an anterior communicating artery aneurysm caused an SAH (Hunt and Hess Grade IV, Fisher Grade III). After clipping, intraparenchymal monitoring (intracranial pressure, brain tissue oxygen tension [P(ti)O(2)], and microdialysis sampling of extracellular glucose, lactate, pyruvate, and glutamate) was initiated. Flow velocities obtained by transcranial Doppler sonography increased in the internal carotid artery (ICA)/middle cerebral artery bilaterally. INTERVENTION: After a decrease of P(ti)O(2) to less than 2 mm Hg and an increase of the lactate-to-pyruvate ratio to 44 in the territorial region of the left ICA, angiography demonstrated a 70 to 80% stenosis of the left ICA, which was dilated by a temporary occlusion balloon. This maneuver normalized the ICA diameter, P(ti)O(2) increased immediately from 1.5 to 40 mm Hg, the lactate-to-pyruvate ratio decreased from 44 to 30, and extracellular glucose increased from 0.4 to 0.9 mmol/L. No major changes in glutamate or intracranial pressure were seen. In the clinical follow-up, the patient showed a good recovery 6 months after SAH. CONCLUSION: Transluminal balloon angioplasty led to a continuous and effective resolution of cerebral vasospasm observed by sustained, improved cerebral biochemical parameters. Both P(ti)O(2) and lactate-to-pyruvate ratio might provide an early diagnosis of severe cerebral vasospasm after SAH and continuous surveillance of threatened tissue regions after transluminal balloon angioplasty.

An auditory brainstem implant system.

Neurofibromastosis type II (NF2) is a condition that may result in bilateral acoustic neuromas. The tumors and their removal may cause profound bilateral deafness. Because the auditory nerve is compromised, people with NF2 are unable to receive a cochlear implant to restore a sensation of hearing. Electrical stimulation of the auditory pathway can provide hearing in such people. This is possible by means of an auditory brainstem implant (ABI). This article focuses on the MED-EL high-rate multichannel ABI system. The system consists of the implanted and external components. Appropriate placement of the ABI is dependent on electrical auditory brainstem response testing performed intra-operatively. Data on a group of European patients implanted with the MED-EL ABI are presented. Results are promising and include some open-set speech ability.

The fronto-orbital osteotomy as plastic-reconstructive approach to the anterior and middle skull base.

Introduction: A combined extra-intracranial access for the operative exploration of tumours of the anterior and middle skull base is indicated when the tumour extends intracranially and simultaneously into the nasal cavity, the paranasal sinuses or the orbit. Methods: Two standardized modifications of the fronto-orbital osteotomy, the fronto-orbito-nasal and the fronto-orbito-zygomatic osteotomy, allow safe removal of skull base tumours in these locations. In extensive skull base tumours, a modified bilateral fronto-orbital-zygomatic osteotomy can be used. Results: Between February 1993 and July 2000 skull base tumours in 111 patients were resected using the presented methods. The most frequent tumour type was meningioma in 29 cases. Complications were encountered in 13 cases (11.7%). Conclusion: The advantages over other approaches are good extra- and intracranial overview and minimal cerebral trauma. Additional transfacial incisions are not usually necessary. Exact repositioning of the fronto-orbital segments leads to optimal aesthetic results. Copyright 2001 European Association for Cranio-Maxillofacial Surgery.