Tobias Rader

Prof. Dr. Tobias Rader

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Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 October 2016 in Otology & Neurotology
Verified
Journal Article
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SHSilke Helbig
Silke Helbig
YAYoussef Adel
Youssef Adel
TRTobias Rader
Tobias Rader
TSTimo Stöver
Timo Stöver
UBUwe Baumann
Uwe Baumann
This study reviewed outcomes of hearing preservation (HP) surgery in a cochlear implant patient population, with clinical follow-up results up to 11 years after implantation. Retrospective case review. Tertiary referral university hospital. Ninety six patients (103 ears) with partial deafness who underwent HP surgery at the University Hospital Frankfurt since 1999 were included. Electrode carriers were Cochlear Slim Straight, MED-EL Standard, Medium, Flex20, and Flex24. Cochlear implantation using the HP surgery technique with either the cochleostomy or round window approach. Pure-tone averages for low frequencies (125 Hz, 250 Hz, 500 Hz, PTAlow) and speech perception scores of the Freiburg monosyllable and number tests in quiet. PTAlow shifts were used to evaluate HP as complete for ≤10 dB, partial between 10 and 30 dB, and minimal for ≥30 dB. Time intervals were: preoperative, postoperative, after 12 months, and long-term (>24 months, mean 51.4 months, range 2–11 years). Impacts of electrode design and surgical approach were analyzed. Postoperatively (n = 103), HP was complete in 32 (31.1%), partial in 49 (47.6%), minimal in 14 (13.6%), and loss of hearing occurred in 8 cases (7.8%). After 12 months (n = 81), HP was complete in 22 (27.2%), partial in 33 (40.7%), minimal in 11 (13.6%), and loss of hearing occurred in 7 additional cases. For long-term outcomes (n = 62) HP was complete in 7 (11.3%), partial in 24 (38.7%), minimal in 9 (14.5%), and loss of hearing occurred in 7 additional cases (total 22/103, 21.4%). Cases with residual hearing who could utilize acoustic amplification (i.e., PTAlow < 80 dB HL) were 82/95 (85.3%) postoperatively, 58/66 (87.9%) after 12 months, and 38/40 (95.0%) for long-term outcomes. Long-term HP is feasible in a subset of patients. Patients with sufficient long-term residual hearing had the prerequisite to benefit from additional acoustic stimulation. No correlation of total hearing loss with etiology, electrode design, or surgical approach was evident. Apart from individual effects of structural damage or inflammation, genetic factors are suggested to influence HP. Cases with total hearing loss still demonstrated successful speech perception in long-term monosyllable recognition scores.

1 May 2013 in Ear & Hearing
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Journal Article
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TRTobias Rader
Tobias Rader
HFHugo Fastl
Hugo Fastl
UBUwe Baumann
Uwe Baumann
The aim of the study was to measure and compare speech perception in users of electric-acoustic stimulation (EAS) supported by a hearing aid in the unimplanted ear and in bilateral cochlear implant (CI) users under different noise and sound field conditions. Gap listening was assessed by comparing performance in unmodulated and modulated Comité Consultatif International Téléphonique et Télégraphique (CCITT) noise conditions, and binaural interaction was investigated by comparing single source and multisource sound fields. Speech perception in noise was measured using a closed-set sentence test (Oldenburg Sentence Test, OLSA) in a multisource noise field (MSNF) consisting of a four-loudspeaker array with independent noise sources and a single source in frontal position (S0N0). Speech simulating noise (Fastl-noise), CCITT-noise (continuous), and OLSA-noise (pseudo continuous) served as noise sources with different temporal patterns. Speech tests were performed in two groups of subjects who were using either EAS (n = 12) or bilateral CIs (n = 10). All subjects in the EAS group were fitted with a high-power hearing aid in the opposite ear (bimodal EAS). The average group score on monosyllable in quiet was 68.8% (EAS) and 80.5% (bilateral CI). A group of 22 listeners with normal hearing served as controls to compare and evaluate potential gap listening effects in implanted patients. Average speech reception thresholds in the EAS group were significantly lower than those for the bilateral CI group in all test conditions (CCITT 6.1 dB, p = 0.001; Fastl-noise 5.4 dB, p < 0.01; Oldenburg-(OL)-noise 1.6 dB, p < 0.05). Bilateral CI and EAS user groups showed a significant improvement of 4.3 dB (p = 0.004) and 5.4 dB (p = 0.002) between S0N0 and MSNF sound field conditions respectively, which signifies advantages caused by bilateral interaction in both groups. Performance in the control group showed a significant gap listening effect with a difference of 6.5 dB between modulated and unmodulated noise in S0N0, and a difference of 3.0 dB in MSNF. The ability to "glimpse" into short temporal masker gaps was absent in both groups of implanted subjects. Combined EAS in one ear supported by a hearing aid on the contralateral ear provided significantly improved speech perception compared with bilateral cochlear implantation. Although the scores for monosyllable words in quiet were higher in the bilateral CI group, the EAS group performed better in different noise and sound field conditions. Furthermore, the results indicated that binaural interaction between EAS in one ear and residual acoustic hearing in the opposite ear enhances speech perception in complex noise situations. Both bilateral CI and bimodal EAS users did not benefit from short temporal masker gaps, therefore the better performance of the EAS group in modulated noise conditions could be explained by the improved transmission of fundamental frequency cues in the lower-frequency region of acoustic hearing, which might foster the grouping of auditory objects.

1 September 2016 in Hearing Research
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Journal Article
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TRTobias Rader
Tobias Rader
JDJulia Döge
Julia Döge
YAYoussef Adel
Youssef Adel
TWTobias Weissgerber
Tobias Weissgerber
UBUwe Baumann
Uwe Baumann

20 September 2008 in European Archives of Oto-Rhino-Laryngology
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Journal Article
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EKEike Krause
Eike Krause
JLJulia P. R. Louza
Julia P. R. Louza
JHJohn-Martin Hempel
John-Martin Hempel
JWJuliane Wechtenbruch
Juliane Wechtenbruch
TRTobias Rader
Tobias Rader
RGRobert Gürkov
Robert Gürkov

1 January 2012 in The Journal of Laryngology & Otology
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Journal Article
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RGR Gürkov
R Gürkov
LML B Filipe Mingas
L B Filipe Mingas
TRTobias Rader
Tobias Rader
JLJ Louza
J Louza
BOB Olzowy
B Olzowy
EKE Krause
E Krause
Objective: To determine the effect of the Meniett® low-pressure generator on the subjective symptoms and audiovestibular disease markers of patients with unilateral Menière's disease unresponsive to betahistine treatment.Methods: Randomised, placebo-controlled, double-blinded, clinical trial at a tertiary referral centre. After ventilation tube placement, patients were randomised to the active treatment or placebo group. Monitoring comprised audiometry and air caloric testing and a vertigo diary (enabling calculation of vertigo and activity scores, and the number of vertigo days, vertigo-free days and sick days).Results: Sixty-eight patients completed the study. For the active treatment versus placebo group, the following pre- and post-treatment values, and significances for treatment effect comparisons, were respectively seen: cumulative vertigo scores, 22.47 and 15.97 vs 20.42 and 19.23 (p = 0.048); vertigo days, 6.5 and 4.08 vs 5.94 and 5.52 (p = 0.102); sick days, 3.08 and 0.78 vs 2.87 and 3.45 (p = 0.041); vertigo-free days, 14.47 and 17.61 vs 15.48 and 17.58 (p = 0.362); activity score, 23.61 and 13.42 vs 24.68 and 20.23 (p = 0.078); low-tone hearing threshold, 49.15 and 53.18 dB nHL vs 41.66 and 46.10 dB nHL (p > 0.05); and slow phase velocity in response to caloric stimulation, 18.86 and 18.72 °/second vs 14.97 and 15.95 °/second, (p > 0.05).Conclusion: Use of the Meniett® low-pressure generator improved patients' vertigo but not their hearing or vestibular function. This safe, minimally invasive treatment is recommended as second-line treatment for unilateral Menière's disease.

1 October 2016 in Otology & Neurotology
Verified
Journal Article
Closed access
TRTobias Rader
Tobias Rader
UBUwe Baumann
Uwe Baumann
TSTimo Stöver
Timo Stöver
TWTobias Weissgerber
Tobias Weissgerber
YAYoussef Adel
Youssef Adel
SHSilke Helbig
Silke Helbig
Objective: The present study reviewed a cochlear implant (CI) patient population after surgery, which received a free-fitting electrode carrier designed for hearing preservation. The aim was to determine the rate of electrode migration of the CI electrodes and present clinical and surgical implications. Study Design: Retrospective patient review. Setting: Tertiary referral university hospital. Patients: Two hundred seventy-eight patients implanted uni- or bilaterally with lateral wall electrodes designed for hearing preservation (358 implants). The control group was 323 patients implanted uni- or bilaterally with preformed perimodiolar electrodes (468 implants). Interventions: Determination of CI electrode migration was conducted according to a clinical test protocol. Revision surgery was offered in confirmed patients of electrode migration. A bone groove was considered to improve the fixation of the electrode. Main Outcome Measures: Audiological testing including speech audiometry, subjective sound quality rating, and bilateral pitch comparison in bilateral patients, as well as radiological examinations, were conducted. Results: Electrode migration was observed solely in patients implanted with lateral wall electrodes; 10 of 358 patients with free-fitting electrodes (2.8%) had electrode migration, which was successfully confirmed by the proposed clinical test protocol. Nine of the 10 confirmed patients underwent reinsertion surgery. Mean perception score decreased from 75.0% to 62.1% after electrode migration and recovered completely after reinsertion surgery. A flowchart to detect electrode migration was designed for clinical practice. Conclusion: Although electrode migration is a rare complication in CI surgery, long-term follow-up diagnostics should include a test protocol to detect electrode shifts of lateral wall electrode arrays. A reinsertion surgery should be conducted in confirmed patients to recover speech perception.