Evaluation of auditory pathway excitability using a pre-operative trans-tympanic electrically evoked auditory brainstem response under local anesthesia in cochlear implant candidates

OBJECTIVE

Subjective promontory stimulation is used to evaluate cochlear implant (CI) candidacy, but the test reliability is low. Electrically evoked auditory brainstem response (EABR) can verify the function of the auditory system objectively. This study's procedure uses a trans-tympanic rounded bent-tip electrode to perform pre-operative EABR under local anaesthesia (LA-TT-EABR) using MED-EL Software and Hardware. This study aimed to determine usability and effectiveness for CI candidates.

DESIGN

We hypothesised that LA-TT-EABR waveforms of good quality would be related to successful hearing outcomes. We assumed that the duration of hearing loss/deafness was a confounding factor to study outcomes.

STUDY SAMPLE

19 borderline CI candidates.

RESULTS

Positive LA-TT-EABR results were confirmed in 14 patients. LA-TT-EABR's mean latency was 2.05 ± 0.31 ms (eII/eIII) and 4.24 ± 0.39 ms (eIV/eV). Latencies weren't statistically different from intra-operative EABR elicited by basal CI contacts. All positive LA-TT-EABR patients benefitted from CI and speech performance improved one year after implantation. One patient with negative LA-TT-EABR was cochlear-implanted and had no hearing sensation.

CONCLUSIONS

LA-TT-EABR is a tool in the frame of pre-operative objective testing the auditory pathway. It seems useful for clinical testing CI candidacy. Based on this study's outcomes, LA-TT-EABR should be recommended for uncertain CI candidates.

Surgical management of choroid plexus papilloma of the cerebellopontine and cerebellomedullary angle: classification and strategy

Choroid plexus papillomas (CPPs) are primary neuroectodermal neoplasms that usually arise in the fourth ventricle in adults. In this study, we present 12 patients with CPP arising from the cerebellopontine angle (CPP-CPA) and/or of the cerebellomedullary angle (CPP-CMA) that were treated in our department. Patients who underwent surgery for the treatment for CPP-CPA/CMA from January 2004 to March 2020 were identified by a computer search of their files from the Department of Neurosurgery, Tübingen. CPPs were classified according to their location into type 1 (tumor portion only in the CPA,), type 2 (tumor portions only in the CMA), and type 3 (tumor portions both in the CPA and CMA). Patients were evaluated for initial symptoms, previous therapies in other hospitals, extent of tumor resection, recurrence rate, and complications by reviewing patient documents. Of approximately 1500 CPA lesions, which were surgically treated in our department in the last 16 years, 12 patients (mean age 42 ± 19 years) were found to have CPP-CPA/CMA. Five were male, and seven were female patients. Gross total resection was achieved in nine cases, and a subtotal resection was attained in three cases. Tumor recurrence in the same location after the first surgery in our hospital was observed in 2 patients after 15 and 40 months of follow-up, and in another patient, distant metastases (C3/4 and L3 levels) were observed. Surgical removal of CPP is the treatment of choice, but additional therapeutic options may be necessary in case of remnant tumor portions, recurrence, or malignant transformation.

[Hearing rehabilitation with the Vibrant Soundbridge in patients with congenital middle ear malformation]

BACKGROUND

Congenital aural atresia, which is usually unilateral, causes hearing loss and aesthetic impairment. Besides tympanoplasty with/without canalplasty and bone conduction devices, active middle ear implants are also available for functional rehabilitation.

OBJECTIVE

This article aims to present a contemporary review on the treatment possibilities for middle ear malformations, with a focus on audiological rehabilitation with the Vibrant Soundbridge.

MATERIALS AND METHODS

A selective literature search for treatment possibilities was performed in PubMed up to October 2020, and personal clinical experiences are reported.

RESULTS

The Vibrant Soundbridge, which is approved for children ≥ 5 years, is suitable for treatment of middle ear malformations with a Jahrsdoerfer score ≥ 5. Although implantation of a Vibrant Soundbridge is surgically more demanding than implantation of a bone conduction device, the method is safe, delivers good auditory results (superior to bone conduction devices in terms of speech understanding and spatial hearing), does not involve intensive postsurgical care, and rarely requires revision surgery. The Vibrant Soundbridge can be coupled to (remnants of) the ossicular chain or the round window.

CONCLUSION

The Vibrant Soundbridge is an appropriate treatment method in patients with middle ear malformations who have suitable anatomical preconditions.

In vivo assessment of tumor heterogeneity in WHO 2016 glioma grades using diffusion kurtosis imaging: Diagnostic performance and improvement of feasibility in routine clinical practice

PURPOSE

To assess the diagnostic performance of normalized and non-normalized diffusion kurtosis imaging (DKI) metrics extracted from different tumor volume data for grading glioma according to the integrated approach of the revised 2016 WHO classification.

MATERIALS AND METHODS

Sixty patients with histopathologically confirmed glioma, who provided written informed consent, were retrospectively assessed between 01/2013 and 08/2016 from a prospective trial approved by the local institutional review board. Mean kurtosis (MK) and mean diffusivity (MD) metrics from DKI were assessed by two blinded physicians from four different volumes of interest (VOI): whole solid tumor including (VOI_tu-ed) and excluding perifocal edema (VOI_tu), infiltrative zone (VOI_ed), and single slice of solid tumor core (VOI_slice). Intra-class correlation coefficient (ICC) was calculated to assess inter-rater agreement. One-way ANOVA was used to compare MK between 2016 CNS WHO tumor grades. Friedman's test compared MK and MD of each VOI. Spearman's correlation coefficient was used to correlate MK with 2016 CNS WHO tumor grades. ROC analysis was performed on MK for significant results.

RESULTS

The MK assessment showed excellent inter-rater agreement for each VOI (ICC, 0.906-0.955). MK was significantly lower in IDH_mutant astrocytoma (0.40±0.07), than in 1p/19q-confirmed oligodendroglioma (0.54±0.10, P=0.001) or IDH_wild-type glioblastoma (0.68±0.13, P<0.001). MK and 2016 WHO tumor grades were strongly and positively correlated (VOI_tu-ed, r=0.684; VOI_tu, r=0.734; VOI_ed, r=0.625; VOI_slice, r=0.698; P<0.001).

CONCLUSIONS

Non-normalized MK values obtained from VOI_tu and VOI_slice showed the best reproducibility and highest diagnostic performance for stratifying glioma according to the integrated approach of the recent 2016 WHO classification.

[Impact of Microsurgical Exstirpation of Vestibular Schwannomas on the Sense of Taste]

Patients with single sided vestibular schwannoma may report about a taste dysfunction apart from the well known cardinal symptoms. Very few data are published so far on that topic. The aim of this study was to investigate the influence of microsurgery for vestibular schwannomas on taste perception prospectively using a well validated taste test. 25 patients could be included in the study. No ageusia was claimed by the patients. In average a decrease of the taste score postoperatively could be detected on the tumor as well as on the non treated side. The differences were not statistically significant. But a subgroup of ¼ of the subjects revealed a new onset of side difference in the taste score that was not present before surgery. In all those cases the treated side showed a clinically significant reduced taste score of 6,2 in average. Within this subgroup the temporal access was overpresented in contrast to the whole group. This may indicate an influence of the choosen approach and that for the position of the tumor to the change of the taste score. The observations should be verified on a greater collective.

[Reporting initiatives. An update on treatment in radiology]

The written radiological report is the most important means of communication between the radiologist and the referring medical doctor. There is no universal definition of a radiological report concerning its structure and content. The majority of clinicians and radiologists prefer structured reporting rather than free text reports of findings. Structured reporting does not increase the quality of a radiological report but has many advantages in research, teaching and quality management. Using standard RadLex terms facilitates translation and ontological assignment of a report. The Reporting Initiative of the Radiological Society of North America (RSNA) offers free and freely available extensively validated best practices radiology report templates in the new management of radiology report templates (MRRT) format according to the guidelines of the Integrating the Healthcare Enterprise (IHE).

[Prospective assessment of quality of life after auricular reconstruction with porous polyethylene]

BACKGROUND

Microtia is associated with increased psychosocial morbidity. The literature contains three purely retrospective studies using validated tools. These studies show that auricular reconstruction leads to a significant improvement in health-related quality of life in affected children and adults.

METHODS

In a prospective approach, the authors assessed 21 consecutive microtia patients (return rate 81 %; 7 children and 10 adults) before and after auricular reconstruction with porous polyethylene using the following validated questionnaires: Glasgow Health Status Inventory (GHSI), Short Form 36 Health Survey Questionnaire (SF-36), Childhood Experiences Questionnaire (CEQ) and Kidscreen-52.

RESULTS

An improved health-related quality of life was detected with all applied instruments.

CONCLUSION

A subjective benefit of auricular reconstruction with porous polyethylene can be shown using prospective, as well retrospective tools.

[IT systems in radiology and IT systems for radiologists]

Radiology plays an important role in introduction and use of information technology (IT) systems in the daily clinical routine. The radiology information system (RIS) and picture archiving and communication system (PACS) are the main systems used in a digital radiology department. In this article the basic principles and functions of these systems and trends in development are described.

[Correlation of pure tone thresholds and hearing loss for numbers. Comparison of three calculation variations for plausibility checking in expertise]

BACKGROUND

The present study analyzes the best combination of frequencies for the calculation of mean hearing loss in pure tone threshold audiometry for correlation with hearing loss for numbers in speech audiometry, since the literature describes different calculation variations for plausibility checking in expertise. Three calculation variations, A (250, 500 and 1000 Hz), B (500 and 1000 Hz) and C (500, 1000 and 2000 Hz), were compared.

METHODS

Audiograms in 80 patients with normal hearing, 106 patients with hearing loss and 135 expertise patients were analyzed in a retrospective manner. Differences between mean pure tone audiometry thresholds and hearing loss for numbers were calculated and statistically compared separately for the right and the left ear in the three patient collectives.

RESULTS

We found the calculation variation A to be the best combination of frequencies, since it yielded the smallest standard deviations while being statistically different to calculation variations B and C. The 1- and 2.58-fold standard deviation (representing 68.3% and 99.0% of all values) was ±4.6 and ±11.8 dB for calculation variation A in patients with hearing loss, respectively.

CONCLUSIONS

For plausibility checking in expertise, the mean threshold from the frequencies 250, 500 and 1000 Hz should be compared to the hearing loss for numbers. The common recommendation reported by the literature to doubt plausibility when the difference of these values exceeds ±5 dB is too strict as shown by this study.

Trigeminal perception is necessary to localize odors

The human ability to localize odorants has been examined in a number of studies, but the findings are contradictory. In the present study we investigated the human sensitivity and ability to localize hydrogen sulphide (H(2)S), which in low concentrations stimulates the olfactory system selectively, the olfactory-trigeminal substance isoamyl acetate (IAA), and the trigeminal substance carbon dioxide (CO(2)). A general requirement for testing of localization was the conscious perception of the applied stimuli by the participants. Using Signal Detection Theory, we determined the human sensitivity in response to stimulation with these substances. Then the subjects' ability to localize the three different substances was tested. We found that humans can detect H(2)S in low concentration (2 ppm) with moderate sensitivity, and possess a high sensitivity in response to stimulation with 8 ppm H(2)S, 17.5% IAA, 50% v/v CO(2). In the localization experiment, subjects could localize neither the low nor the high concentration of H(2)S. In contrast, subjects possessed the ability to localize IAA and CO(2) stimuli. These results clearly demonstrate that humans, in spite of the aware perception, are not able to localize substances which only activate the olfactory system independent of their concentration, but they possess an ability to localize odorants that additionally excite the trigeminal system.

[The hard-of-hearing patient--what should the general practitioner do?]

When assessing hardness of hearing, the physician must in the first instance differentiate between an acute event--for example sudden loss of hearing--and chronic deafness. Otoscopy, tuning fork testing and measurement of hearing distance provide importance information for the differentiation of hardness of hearing. In the case of noise deafness, the general physician has a preventive task. With regard to the provision of a hearing aid he can play a supportive role as a mediator between the hearing aid wearer, the ENT specialist and the acoustician.

Functional outcome after gamma knife treatment in vestibular schwannoma

Radiosurgery (RS) is a noninvasive, ambulatory special neurosurgical procedure for the treatment of vestibular schwannoma (VS). We treated 123 patients with unilateral schwannomas between 1994 and 2000 at the gamma knife (GK) center in Munich using a primary stereotactic procedure. These patients were followed up until June 2004 in respect to audiological, neurological, neurootological and radiological features before and after radiosurgical intervention. The actual tumor control rate of 8.2 years (mean) after GK surgery for all patients and a single treatment was calculated to be 96.7%. The impairment of hearing was on average 18% after GK, ranking from 0% gain of hearing loss up to 90%. Facial nerve function, graded according to the House-Brackmann scale, deteriorated in none of the patients; 5.8% reported a trigeminal neuralgia. Tinnitus developed in 4.1% of the patients after RS; 13.3% had vertigo for the first time after the treatment, age apparently being a predisposing factor. Radiosurgical treatment for VS is an alternative to microsurgery (MS). It is associated with a lower rate of facial and trigeminal neuropathy, postoperative complications and hospital stay. The hearing preservation rate is equivalent to MS.

[Treatment of hearing impairment in children]

The prerequisite for normal speech development is the ability to hear normally. Our objective here is the detection of a hearing deficit with a relevant impact on the acquisition of speech before the child is three months old. Such a hearing impairment due to sensorineural deafness requires the provision of a hearing aid, which needs to be done before the child is six months old. If the provision of a hearing aid fails to provide the desired results, or if they may no longer be expected, a cochlear implant is indicated. In the event of tympanic effusion persistence, an adenotomy with paracentesis, and possibly the insertion of an ear tube, is indicated. This intervention can be done before the child is one year old. Permanent sound-conduction deafness may be due to auditory canal atresia or middle ear anomalies. In such cases, it is important to establish whether surgical reconstruction, for example of the sound conduction system, can restore good hearing over the long term. Prior to surgery at the age of about five, the child must be provided with a hearing aid.

Niikawa-Kuroki-Syndrom

Niikawa-Kuroki syndrome (Kabuki make-up syndrome) is a congenital disorder with characteristic facial features and possibly anomalies of the skeletal system and internal organs. There is an increasing number of reports of patients with combined hearing impairment, inner ear deformities or sensorineural hearing impairment. In addition, the patients often suffer from therapy-resistant chronic otitis media. In addition to multiple cardiac and renal deformities, our 3 year old patient has a hearing impairment due to chronic otitis media with chronic otorrhea, and requires a hearing aid. A high-definition CT scan of the petrosal bone revealed, for the first time in a patient with Niikawa-Kuroki syndrome, a large vestibular aqueduct syndrome and deformities of the vestibular system. We examine the problems involved with treating chronic otorrhea in chronic otitis media and providing patients with BTE hearing aids.

[Localized invasive intracranial aspergillosis with multiple cranial nerve failure -- case report and review of the literature]

Contrary to the more frequent hematogenously spread cerebral aspergillosis, localized invasive intracranial aspergillosis is a fungal infection that can also occur in patients who are not severely immunosuppressed. This illness can be effectively treated in some of these patients by early and rigorous therapy. Localized invasion of the fungus, generally from one of the nasal sinuses, causes intracranial growth mainly along the base of the skull and larger vessels,where fibrous, granulomatous tissue develops. This generally leads to damage of the cranial nerves (primarily I-VI) as well as localized pain syndromes. We report on the clinical course documented by MRI of a patient with localized invasive intracranial aspergillosis who had multiple failure of cranial nerves following surgery for an aspergilloma of the maxillary sinus. Clinical course, imaging findings, and treatment of the illness are discussed with a review of the relevant literature.

[Detection of humoral immune response to inner ear proteins in patients with sensorineural hearing loss]

BACKGROUND

The precise mechanism of inner ear disease is still unknown. An autoimmune reaction could be one of several possible pathogenic factors involved in progressive sensorineural hearing loss. Heat shock protein 70 is suggested to play an important role in the development of autoimmune diseases. The aim of this study is the investigation of humoral immune reactivity to inner ear components in patients with sensorineural hearing loss.

METHODS

The presence of antibodies to inner ear components was determined by immuno-blotting extracted bovine or human inner ear proteins. Study groups consisted of patients with idiopathic progressive sensorineural hearing loss (group A), patients with Menière's disease (group B), patients with sudden hearing loss (group C), patients with otosclerosis (group D), patients with Cogan's disease (group E), and individuals without hearing problems (group F).

RESULTS

40% of the patients with progressive sensorineural hearing loss showed reactivity against a 68-kDa protein extracted from bovine inner ear. In contrast to this, only 5% of healthy individuals and 10% with Menière's disease showed reactivity against the 68-kDa protein from bovine inner ear or against bovine heat shock protein 70. Some of the patients who showed reactivity against bovine inner ear proteins were tested with human inner ear and human heat shock protein 70; all of these showed reactivity. Approximately 6% of the patients with sudden hearing loss (group C), otosclerosis (group D), and Cogan's disease (group E) showed reactivity to inner ear proteins. A non-specific humoral immune reaction against inner ear proteins with molecular weights of 30, 40, 50, 60, and 220 kDa was observed in all patients.

DISCUSSION

These results indicate a humoral immune reactivity against heat shock protein 70, which might be responsible for the pathogenesis of progressive sensorineural hearing loss.

Tertiary trisomy in a human kindred containing an E/G translocation

Images

Familial Mongolism (Trisomy-21 Syndrome) Resulting from a "15/21" Chromosome Translocation in More than Three Generations of a Large Kindred

Images