Structure and establishment of the German Cochlear Implant Registry (DCIR).

Hearing rehabilitation of patients with severe hearing loss or deafness using cochlear implants (CI) is a very successful but also complex and lifelong process that requires high quality standards for structure, process, and results. Medical registries represent an ideal tool for conducting quality control relevant to care while at the same time collecting scientific data. Therefore, at the initiative of the Executive Committee of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery (DGHNO-KHC), a Germany-wide CI registry (the German Cochlear Implant Register, DCIR) was to be established. The following goals were to be achieved: 1) legal and contractual basis for the register; 2) definition of the register contents; 3) development of evaluation standards (hospital-specific and national annual reports); 4) development of a logo; 5) practical operation of the registry. After defining a catalog of services that defines the content, structure, and operation of the DCIR, a registry operator with audiological expertise was sought. After considering various offers, the registry was technically implemented in cooperation with the provider INNOFORCE (Ruggell, Liechtenstein) as registry operator. This also included the realization of an interface for data transfer from previously existing databases and development of a data protection concept for productive operation of the DCIR under the scientific leadership of the DGHNO-KHC Executive Committee. Since January 2022, it has been possible for participating hospitals to enter pseudonymized data into the DCIR. To date, 75 hospitals in Germany have contractually agreed to participate in the registry. During the first 15 months, data from over 2500 implants in over 2000 patients were registered in the DCIR. The work presented here describes the structuring, development, and successful establishment of the DCIR. Introduction of the DCIR represents an important milestone of future scientifically based quality control in CI care. The registry presented here can therefore be considered as an example for other areas of medical care and thus also sets an international standard.

Conception and implementation of a certification system for quality control of cochlear implant treatment in Germany.

A standardized and structured process is indispensable for optimal hearing rehabilitation with cochlear implants (CI). The Executive Committee of the German Society of Otorhinolaryngology, Head and Neck Surgery (DGHNO-KHC), initiated the conception of a certification program and a Whitepaper based on the Association of the Scientific Medical Societies in Germany (AWMF) clinical practice guideline (CPG) describing the current medical standards of CI care in Germany. The goal was to independently confirm implementation of this CPG and make this information publicly available. With the support of an independent certification organization, successful implementation of the CI-CPG by a hospital would then be verified and confirmed by awarding the "Cochlear implant-provision institution" (Cochlea-Implantat-versorgende Einrichtung, CIVE) quality certificate. A structure for implementation of a certification system was developed based on the CI-CPG. The following steps were required: 1) conception of a quality control system for certification of hospitals working in accordance with the CI-CPG; 2) development of required structures for an independent review of quality-relevant structure, process, and result parameters; 3) development of a standard procedure for independent certification of hospitals; 4) development of a certificate and a logo to demonstrate successful certification; 5) practical implementation of the certification. Following design of the certification program and the required organizational structure, the certification system was successfully launched in 2021. Applications for the quality certificate could be formally submitted from September 2021. A total of 51 off-site evaluations were performed by December 2022. In the first 16 months from introduction, 47 hospitals were successfully certified as CIVE. In this period, 20 experts were trained as auditors, who have since then carried out 18 on-site audits in hospitals. In summary, the conceptual design, structure, and practical implementation of a certification program for quality control in CI care was successfully implemented in Germany.

[Structure and establishment of the German Cochlear Implant Registry]. / Struktur und Einrichtung des Deutschen Cochlea-Implantat-Registers (DCIR).

Hearing rehabilitation of patients with severe hearing loss or deafness using cochlear implants (CI) is a very successful but also complex and lifelong process that requires high quality standards for structure, process, and results. Medical registries represent an ideal tool for conducting quality control relevant to care while at the same time collecting scientific data. Therefore, at the initiative of the Executive Committee of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery (DGHNO-KHC), a Germany-wide CI registry (the German Cochlear Implant Register, DCIR) was to be established. The following goals were to be achieved: 1) legal and contractual basis for the register; 2) definition of the register contents; 3) development of evaluation standards (hospital-specific and national annual reports); 4) development of a logo; 5) practical operation of the registry. After defining a catalog of services that defines the content, structure, and operation of the DCIR, a registry operator with audiological expertise was sought. After considering various offers, the registry was technically implemented in cooperation with the provider INNOFORCE (Ruggell, Liechtenstein) as registry operator. This also included the realization of an interface for data transfer from previously existing databases and development of a data protection concept for productive operation of the DCIR under the scientific leadership of the DGHNO-KHC Executive Committee. Since January 2022, it has been possible for participating hospitals to enter pseudonymized data into the DCIR. To date, 75 hospitals in Germany have contractually agreed to participate in the registry. During the first 15 months, data from over 2500 implants in over 2000 patients were registered in the DCIR. The work presented here describes the structuring, development, and successful establishment of the DCIR. Introduction of the DCIR represents an important milestone of future scientifically based quality control in CI care. The registry presented here can therefore be considered as an example for other areas of medical care and thus also sets an international standard.

[Conception and implementation of a certification system for quality control of cochlear implant treatment in Germany. German version]. / Konzeption und Implementierung eines Zertifizierungssystems zur Qualitätssicherung der Cochlea-Implantat-Versorgung in Deutschland.

A standardized and structured process is indispensable for optimal hearing rehabilitation with cochlear implants (CI). The Executive Committee of the German Society of Otorhinolaryngology, Head and Neck Surgery (DGHNO-KHC), initiated the conception of a certification system and a Whitepaper based on the Association of the Scientific Medical Societies in Germany (AWMF) clinical practice guideline (CPG) describing the current medical standards of CI care in Germany. The goal was to independently confirm implementation of this CPG and make this information publicly available. With the support of an independent certification organization, successful implementation of the CI-CPG by a hospital would then be verified and confirmed by awarding the "Cochlear implant-provision institution" (Cochlea-Implantat-versorgende Einrichtung, CIVE) quality certificate. A structure for implementation of a certification system was developed based on the CI-CPG. The following steps were required: 1) conception of a quality control system for certification of hospitals working in accordance with the CI-CPG; 2) development of required structures for an independent review of quality-relevant structure, process, and result parameters; 3) development of a standard procedure for independent certification of hospitals; 4) development of a certificate and a logo to demonstrate successful certification; 5) practical implementation of the certification. Following design of the certification system and the required organizational structure, the certification system was successfully launched in 2021. Applications for the quality certificate could be formally submitted from September 2021. A total of 51 off-site evaluations were performed by December 2022. In the first 16 months from introduction, 47 hospitals were successfully certified as CIVE. In this period, 20 experts were trained as auditors, who have since then carried out 18 on-site audits in hospitals. In summary, the conceptual design, structure, and practical implementation of a certification system for quality control in CI care was successfully implemented in Germany.

Randomized Controlled Trial of a Cohesive Eight-Week Evolution Unit That Incorporates Molecular Genetics and Principles of the Next Generation Science Standards.

In response to calls for curricular materials that integrate molecular genetics and evolution and adhere to the K-12 Next Generation Science Standards (NGSS), the Genetic Science Learning Center (GSLC) at the University of Utah has developed and tested the "Evolution: DNA and the Unity of Life" curricular unit for high school biology. The free, 8-week unit illuminates the underlying role of molecular genetics in evolution while providing scaffolded opportunities to engage in making arguments from evidence and analyzing and interpreting data.  We used a randomized controlled trial design to compare student learning when using the new unit with a condition in which teachers used their typical (NGSS-friendly) units with no molecular genetics. Results from nationwide testing with 38 teachers (19 per condition) and their 2269 students revealed that students who used the GSLC curriculum had significantly greater pre/post gain scores in their understanding of evolution than students in the comparison condition; the effect size was moderate. Further, teacher implementation data suggest that students in the treatment condition had more opportunities to engage in argumentation from evidence and have in-class discussions than students in the comparison classes. We consider study implications for the secondary and postsecondary science education community.

Constructed wetlands for combined sewer overflow treatment: A state-of-the-art review.

Combined sewer overflows (CSOs) are a major source of surface water pollution and degradation. This is particularly visible where sewage collection with combined sewer and centralized treatment are well established, such as in Europe and North America: an overwhelming number of surface water bodies are in insufficient status of ecology, hydrology and physico-chemical parameters. Therefore, several countries have started implementing constructed wetlands (CWs) as mainstream on-spot treatment. This paper summarizes the main design approaches that can be adopted. We identified eight different schemes for the implementation of CSO-CWs, based on our international experience and documented by a literature analysis. The performance review includes conventional water quality parameters, as well as pathogen and emergent contaminant removal. Furthermore, modelling tools for advanced design and for understanding a wide applicability of these green infrastructures are presented. This paper also provides a review on other side benefits offered by the adoption of Nature-Based Solutions for CSO treatment, such as ecosystem services, and the most common issues related to their operation and maintenance. Our analysis has produced a list of key factors for design and operation, all derived from full-scale installations in operation up to more than ten years.

High-flux ultrafast extreme-ultraviolet photoemission spectroscopy at 18.4 MHz pulse repetition rate.

Laser-dressed photoelectron spectroscopy, employing extreme-ultraviolet attosecond pulses obtained by femtosecond-laser-driven high-order harmonic generation, grants access to atomic-scale electron dynamics. Limited by space charge effects determining the admissible number of photoelectrons ejected during each laser pulse, multidimensional (i.e. spatially or angle-resolved) attosecond photoelectron spectroscopy of solids and nanostructures requires high-photon-energy, broadband high harmonic sources operating at high repetition rates. Here, we present a high-conversion-efficiency, 18.4-MHz-repetition-rate cavity-enhanced high harmonic source emitting 5 × 105 photons per pulse in the 25-to-60-eV range, releasing 1 × 1010 photoelectrons per second from a 10-µm-diameter spot on tungsten, at space charge distortions of only a few tens of meV. Broadband, time-of-flight photoelectron detection with nearly 100% temporal duty cycle evidences a count rate improvement between two and three orders of magnitude over state-of-the-art attosecond photoelectron spectroscopy experiments under identical space charge conditions. The measurement time reduction and the photon energy scalability render this technology viable for next-generation, high-repetition-rate, multidimensional attosecond metrology.

Induction chemotherapy (IC) followed by radiotherapy (RT) versus cetuximab plus IC and RT in advanced laryngeal/hypopharyngeal cancer resectable only by total laryngectomy-final results of the larynx organ preservation trial DeLOS-II.

Background: The German multicenter randomized phase II larynx organ preservation (LOP) trial DeLOS-II was carried out to prove the hypothesis that cetuximab (E) added to induction chemotherapy (IC) and radiotherapy improves laryngectomy-free survival (LFS; survival with preserved larynx) in locally advanced laryngeal/hypopharyngeal cancer (LHSCC). Patients and methods: Treatment-naïve patients with stage III/IV LHSCC amenable to total laryngectomy (TL) were randomized to three cycles IC with TPF [docetaxel (T) and cisplatin (P) 75 mg/m2/day 1, 5-FU (F) 750 mg/m2/day days 1-5] followed by radiotherapy (69.6 Gy) without (A) or with (B) standard dose cetuximab for 16 weeks throughout IC and radiotherapy (TPFE). Response to first IC-cycle (IC-1) with ≥30% endoscopically estimated tumor surface shrinkage (ETSS) was used to define early responders; early salvage TL was recommended to non-responders. The primary objective was 24 months LFS above 35% in arm B. Results: Of 180 patients randomized (July 2007 to September 2012), 173 fulfilled eligibility criteria (A/B: larynx 44/42, hypopharynx 41/46). Because of 4 therapy-related deaths among the first 64 randomized patients, 5-FU was omitted from IC in the subsequent 112 patients reducing further fatal toxicities. Thus, IC was TPF in 61 patients and TP in 112 patients, respectively. The primary objective (24 months LFS above 35%) was equally met by arms A (40/85, 47.1%) as well as B (41/88, 46.6%). One hundred and twenty-three early responders completed IC+RT; their overall response rates (TPF/TP) were 94.7%/87.2% in A versus 80%/86.0% in B. The 24 months overall survival (OS) rates were 68.2% and 69.3%. Conclusions: Despite being accompanied by an elevated frequency in adverse events, the IC with TPF/TP plus cetuximab was feasible but showed no superiority to IC with TPF/TP regarding LFS and OS at 24 months. Both early response and 24 months LFS compare very well to previous LOP trials and recommend effective treatment selection and stratification by ETSS. Clinical trial information: NCT00508664.

[Management of acute vertigo and dizziness : Patients in emergency departments in Germany]. / Primärversorgung von akutem Schwindel : Patienten in Notfallambulanzen in Deutschland.

BACKGROUND: Dizziness and vertigo are some of the most common reasons for seeking medical help. Acute dizziness and vertigo require interdisciplinary cooperation. New diagnostic methods (the video head impulse test) and modern algorithms (HINTS: head impulse test/nystagmus [direction changing]/test-of-skew) are increasingly used in case of the acute vestibular syndrome in emergency care. METHODS: In a survey on the management and participation of the ENT specialist area, the authors interviewed 168 German ENT clinics during the spring of 2017 using an online survey. RESULTS: Of the 168 departments, 100 departments participated in the survey. The specialties with first medical contact in cases with acute vertigo were ENT (48%), neurology (32%), and internal medicine (17%). Most of the patients were hospitalized. Patients with acute dizziness were referred most commonly to the ENT (62%) and neurology (16%) departments for further therapy, rarely, to internal medicine wards. For emergency diagnostic workup, the video head impulse test is frequently used in ENT (72%). CONCLUSIONS: In acute vertigo syndromes, the ENT physician has a special role and responsibility in the interdisciplinary workup, since ontological disorders are the most common cause. In any case, an ENT consultation is recommended. In German emergency departments, otorhinolaryngologists use modern diagnostic tools and algorithms such as the video head pulse test and HINTS to objectify peripheral vestibulopathy or identify central causes. Thus, this is a contribution to improving medical care.

[Surgical techniques for treatment of vestibular schwannoma]. / Chirurgische Techniken zur Behandlung des Vestibularisschwannoms.

BACKGROUND: Microsurgical resection of vestibular schwannomas is demanding, even if not all of these tumors represent a challenge for experienced surgeons. In order to make the right decisions when it comes to balancing the extent of tumor resection with preservation of function, the surgeon must possess detailed knowledge of the surgical techniques and also have mastered these. OBJECTIVE: The current article describes the state-of-the-art of the three major microsurgical techniques for resection of vestibular schwannomas, their pearls and their perils. MATERIALS AND METHODS: The literature-based review of the three surgical techniques is complemented by a discussion of operative nuances and weighting of advantages and possible complications based on the authors' own experience. RESULTS: The translabyrinthine, retrosigmoidal, and subtemporal microsurgical approaches are well documented in the literature regarding their modifications and the achievable surgical results. Hearing preservation is possible with the latter two approaches. The choice of approach and the preservation of neural function depend primarily on the size of the tumor and pre-existing neurologic deficits. Preoperative diagnostics and preparation differ only for semi-sitting patient positioning, where transesophageal echocardiography is required. The classic surgical techniques have been supplemented by fine-tuned electrophysiologic monitoring, endoscopic views, special microinstruments, and intraoperative image guidance. CONCLUSION: The choice of surgical approach often depends on the personal preference and experience of the surgeon. Preoperative hearing and tumor extension are the main objective selection criteria.

Inpatient treatment of patients with acute idiopathic peripheral facial palsy: A population-based healthcare research study.

OBJECTIVES: To determine the inpatient management for patients with acute idiopathic facial palsy (IFP) in Thuringia, Germany. DESIGN: Population-based study. SETTING: All inpatients with IFP in all hospitals with departments of otolaryngology and neurology in 2012, in the German federal state, Thuringia. MAIN OUTCOME MEASURES: Patients' characteristics and treatment were compared between departments, and the probability of recovery was tested. RESULTS: A total of 291 patients were mainly treated in departments of otolaryngology (55%) and neurology (36%). Corticosteroid treatment was the predominant therapy (84.5%). The probability to receive a facial nerve grading (odds ratio [OR=12.939; 95% confidence interval [CI]=3.599 to 46.516), gustatory testing (OR=6.878; CI=1.064 to 44.474) and audiometry (OR=32.505; CI=1.485 to 711.257) was significantly higher in otolaryngology departments, but lower for cranial CT (OR=0.192; CI=0.061 to 0.602), cerebrospinal fluid examination (OR=0.024; CI=0.006 to 0.102). A total of 131 patients (45%) showed a recovery to House-Brackmann grade≤II. A pathological stapedial reflex test (Hazard ratio [HR]=0.416; CI=0.180 to 0.959) was the only independent diagnostic predictor of worse outcome. Prednisolone dose >500 mg (HR=0.579; CI 0.400 to 0.838) and no adjuvant physiotherapy (HR=0.568; CI=0.407 to 0.794) were treatment-related predictors of worse outcome. CONCLUSIONS: Inpatient treatment of IFP seems to be highly variable in daily practice, partly depending on the treating discipline and despite the availability of evidence-based guidelines. The population-based recovery rate was worse than reported in clinical trials.

[Surgical indications and complications management in vestibular schwannoma]. / Chirurgische Indikation und Komplikationsmanagement beim Vestibularisschwannom.

BACKGROUND: Recent surgical treatment concepts for patients with vestibular schwannoma (VS) require an interdisciplinary approach as well as recognition and mastering of complications. OBJECTIVE: This paper provides an overview of indications, as well as possible options for function preservation and management of complications in the surgical resection of these tumors. METHODS: Up-to-date treatment concepts and surgical indications were differentiated according to size and extent of tumors. The frequency of important complications was extracted from the literature. Technical options to avoid and correct complications were compiled from personal experience and review of the literature. RESULTS: Complications unrelated to cranial nerves are not infrequent, particularly in older patients. Small and medium-sized tumors that do not reach the fundus and cochlear fossa can be completely removed with good chances of hearing preservation. As long as these tumors do not grow, patients benefit from observation. Large tumors are overrepresented in surgical series compared to their prevalence. Postoperative facial nerve function correlates to tumor volume. Hearing preservation in these tumors is rare. Intraoperative electrophysiological techniques are valuable for attempted preservation of cranial nerve function. Persistent facial palsies can be remedied by dynamic and static interventions for facial rehabilitation. CONCLUSION: Mortality and morbidity associated with surgical treatment of VS are very acceptable. Surgical concepts should be custom-tailored to the individual patient in order to ensure high quality of life.

A Cost-Effectiveness Analysis of Nintedanib in Idiopathic Pulmonary Fibrosis in the UK.

BACKGROUND: International guidelines recommend nintedanib (OFEV®) as an option for the treatment of idiopathic pulmonary fibrosis (IPF). OBJECTIVE: The objective of this study was to assess the cost effectiveness of nintedanib versus pirfenidone, N-acetylcysteine and best supportive care (BSC) for the treatment of IPF from a UK payer's perspective. METHODS: A Markov model was designed to capture the changes in the condition of adults with IPF. Efficacy outcomes included mortality, lung function decline and acute exacerbations. Treatment safety (serious adverse events) and tolerability (overall discontinuation) were also considered. The baseline risk of these events was derived from patient-level data from the placebo arms of nintedanib clinical trials (TOMORROW, INPULSIS-1, INPULSIS-2). A network meta-analysis (NMA) was conducted to estimate the relative effectiveness of the comparator treatments. Quality of life and healthcare resource use data from the clinical trials were also incorporated in the economic model. RESULTS: Nintedanib showed statistically significant differences against placebo on acute exacerbation events avoided and lung function decline. In the cost-effectiveness analysis, the results were split between two treatments with relative low costs and modest effectiveness (BSC and N-acetylcysteine) and two that showed improved effectiveness (lung function) and higher costs (nintedanib and pirfenidone). All comparators were assumed to have similar projected survival and the difference in quality-adjusted life-years (QALYs) was driven by the acute exacerbations and lung function estimates. In the base-case deterministic pairwise comparison with pirfenidone, nintedanib was found to have fewer acute exacerbations and resulted in less costs and more QALYs gained. CONCLUSIONS: Compared with BSC (placebo), nintedanib and pirfenidone were the only treatments to show statistical significance in the efficacy parameters. We found substantial uncertainty in the overall cost-effectiveness results between nintedanib and pirfenidone. N-Acetylcysteine was largely similar to BSC but with a worse survival profile. INPULSIS-1 and INPULSIS-2 ClinicalTrials.gov numbers, NCT01335464 and NCT01335477.

The content validity of the PSS in patients with plaque psoriasis.

BACKGROUND: The primary objective of this study was to evaluate the content validity of the Psoriasis Symptom Scale (PSS), with a specific focus on understanding of the content of the PRO measure by conducting one-on-one interviews with patients with moderate to severe plaque psoriasis. This was a cross-sectional, qualitative study conducted with 20 patients with plaque psoriasis who participated in in-person, one-on-one interviews. Participants were asked to describe their psoriasis symptoms, completed the PSS, and were cognitively debriefed on its content. Interviews were conducted in two separate rounds. Following Round 1, the study data were examined to determine if modifications to the PSS were required. All interviews were audio-recorded and transcribed. Sociodemographic and clinical data were collected for sample descriptive purposes. RESULTS: The 20 study participants had a mean age of 50.2 ± 12.0 years (range: 25.0-73.0), and 55% were female. Thirty-five percent of the sample reported their psoriasis severity as moderate or severe. The average time since diagnosis of plaque psoriasis was almost 18 years, ranging from less than one to over 38 years. The most frequently reported symptoms and signs during the concept elicitation portion of the interviews included redness (N = 20, 100%), itching (n = 20, 100%), pain (n = 15, 75%), burning (n = 13, 65%), and flaking (n = 11, 55%). Overall, participants provided positive feedback on the PSS and felt that it was comprehensive and relevant to their experience with psoriasis. The item meaning and response options were well-understood for the majority of the items. Findings indicate that for the patient-reported symptom of redness, which is also a sign that can be reported by clinicians, redness or the perception of redness is most accurately captured by patient report. Study results did not support modifications to the instrument and no changes to the PSS were recommended. CONCLUSION: The evidence gained in this study provided support for the content validity of the PSS for use as clinical trial endpoint among patients with plaque psoriasis. This study found that the symptoms included in the PSS are important to and well-understood by patients with plaque psoriasis. The PSS is appropriate for inclusion in future studies designed to measure the effect of treatment on psoriasis-related symptoms.

[Vestibular schwannoma - management and microsurgical results]. / Vestibularisschwannom ­ Management und mikrochirurgische Ergebnisse.

BACKGROUND: The experience of the medical team, interdisciplinarity, quality of the physician-patient relationship, sensible use of modern technology, and a sound knowledge about the long-term results of observation and interventions all influence treatment quality in patients with vestibular schwannomas. OBJECTIVES: Compilation of findings regarding the results of observation and microsurgical treatment of patients with these tumors. Deduction of strategies for the medical management from these data. MATERIALS AND METHODS: Review of the pertinent literature concerning the course of the disease with observational management and microsurgical treatment with respect to tumor growth and symptoms. RESULTS: Reported annual growth rates of vestibular schwannoma vary between 0.3 and 4.8 mm. Vertigo is the symptom that is most influential on quality of life regardless of the medical management strategy. Up to 75 % of patients are treated within 5 years of the primary diagnosis. Independent of the approach, reported resection rates are higher than 95 %, even with preservation of function as the primary goal. Recurrence rates after subtotal removal are three times higher than after complete removal. Facial nerve preservation is accomplished in more than 90 % of cases. With functional hearing before surgery and small tumors, the chance of hearing preservation exceeds 50 %. CONCLUSIONS: Quality of life is primarily defined by symptoms caused by the tumor itself and only secondarily by the medical interventions. Treatment should be directed towards the preservation of the patient's quality of life from the beginning. Results of medical treatment should be superior to the natural course of the disease.

[Early acoustic evoked potentials in patients with "small" vestibular schwannomas]. / Frühe akustisch evozierte Potenziale bei Patienten mit "kleinem" Vestibularisschwannom.

BACKGROUND: The prognostic potential of click-evoked early acoustic evoked potentials (EAEP) for vestibular schwannoma (VS) diagnostics is considered insufficient for tumors small than approximately <1.5 cm in diameter. However, up until now, the derivations at higher sound pressure levels have mainly been used for EAEP evaluation. The aim of this study was to examine whether registered EAEP are more sensitive to pathological changes at low sound pressure levels and with smaller tumors. METHODS: Comparative examinations (pair-matched) were conducted with 34 patients. An appropriate patient with an identical hearing level threshold - either a purely cochlear hearing deficiency or a normal hearing level - was matched to each tumor patient. EAEP were registered at 80, 60, and 40 dB HL. The characteristic parameters where assessed visually and evaluated statistically, both in respect to patient groups and in bilateral comparisons. Furthermore, the relationship between the level-dependent wave V latency differences in bilateral comparison and tumor size were evaluated. RESULTS: Low-level cochlear hearing deficiencies did not cause a change in wave V latency, such that the pathological side differences at 40 dB HL in patients with VS can be considered a "purely" retrocochlear hearing deficiency. The sensitivity of EAEP registered at 40 dB HL decreases only with tumors under about <5 mm in diameter. Combining the values of wave V latency and interaural wave V latency difference effectively reduces false-positive findings at 40 dB HL to zero. CONCLUSION: Beyond the suprathreshold derivations, potential registrations at 40 dB HL can also be diagnostically useful to differentiate cochlear from retrocochlear lesions. In the case of small VS and good hearing levels, these registrations may also be used for intraoperative monitoring to allow better evaluation of level-dependent changes in the auditory nerve.