John Martin Hempel

Prof. Dr. John Martin Hempel


Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

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

Representative Publications

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2 June 2006 in European Archives of Oto-Rhino-Laryngology
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Journal Article
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JHJohn Martin Hempel
John Martin Hempel
EHE. Hempel
E. Hempel
BWB. Wowra
B. Wowra
CSCh. Schichor
Ch. Schichor
AMA. Muacevic
A. Muacevic
ARA. Riederer
A. Riederer

29 May 2021 in European Archives of Oto-Rhino-Laryngology
Verified
Journal Article
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JSJennifer L. Spiegel
Jennifer L. Spiegel
Daniel Polterauer-Neuling (née Polterauer)Daniel Polterauer-Neuling (née Polterauer)
Daniel Polterauer-Neuling (née Polterauer)
JHJohn Martin Hempel
John Martin Hempel
MCMartin Canis
Martin Canis
JSJudith Spiro
Judith Spiro
JMJoachim Müller
Joachim Müller
Purpose: In cochlear implantation, thorough preoperative planning together with measurement of the cochlear duct length (CDL) assists in choosing the correct electrode length. For measuring the CDL, different techniques have been introduced in the past century along with the then available technology. A tablet-based software offers an easy and intuitive way to visualize and analyze the anatomy of the temporal bone, its proportions and measure the CDL. Therefore, we investigated the calculation technique of the CDL via a tablet-based software on our own cohort retrospectively.Methods: One hundred and eight preoperative computed tomography scans of the temporal bone (slice thickness < 0.7 mm) of already implanted FLEX28™ and FLEXSOFT™ patients were found eligible for analysis with the OTOPLAN software. Measurements were performed by two trained investigators independently. CDL, angular insertion depth (AID), and cochlear coverage were calculated and compared between groups of electrode types, sex, sides, and age.Results: Mean CDL was 36.2 ± 1.8 mm with significant differences between sex (female: 35.8 ± 0.3 mm; male: 36.5 ± 0.2 mm;p = 0.037), but none concerning side or age. Differences in mean AID (FLEX28: 525.4 ± 46.4°; FLEXSOFT: 615.4 ± 47.6°), and cochlear coverage (FLEX28: 63.9 ± 5.6%; FLEXSOFT: 75.8 ± 4.3%) were significant (p < 0.001).Conclusion: A broad range of CDL was observed with significant larger values in male, but no significant differences concerning side or age. Almost every cochlea was measured longer than 31.0 mm. Preoperative assessment aids in prevention of complications (incomplete insertion, kinking, tipfoldover), attempt of atraumatic insertion, and addressing individual necessities (hearing preservation, cochlear malformation). The preferred AID of 720° (two turns of the cochlea) was never reached, opening the discussion for the requirement of longer CI-electrodes versus a debatable audiological benefit for the patient in his/her everyday life.

16 September 2008 in Malaria Journal
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RGRobert Gürkov
Robert Gürkov
TETeferi Eshetu
Teferi Eshetu
IMIsabel Barreto Miranda
Isabel Barreto Miranda
NBNicole Berens-Riha
Nicole Berens-Riha
YMYoseph Mamo
Yoseph Mamo
TLThomas Löscher
Thomas Löscher
Due to increasing drug resistance, artemisinin-based combination chemotherapy (ACT) has become the first-line treatment of falciparum malaria in many endemic countries. However, irreversible ototoxicity associated with artemether/lumefantrine (AL) has been reported recently and suggested to be a serious limitation in the use of ACT. The aim of the study was to compare ototoxicity, tolerability, and efficacy of ACT with that of quinine and atovaquone/proguanil in the treatment of uncomplicated falciparum malaria.

1 September 2004 in Otology & Neurotology
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Journal Article
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JHJohn Martin Hempel
John Martin Hempel
LJLorenz Jäger
Lorenz Jäger
UBUwe Baumann
Uwe Baumann
EKEike Krause
Eike Krause
GRGerd Rasp
Gerd Rasp
Investigate whether the cochleostomy is a possible port of entry for pneumolabyrinth and a resulting vertigo in patients provided with a cochlear implant. Retrospective case review. Ludwig-Maximilians University of Munich, Hospital Grosshadern. 62-year-old patient who underwent implantation of a HiFocus II cochlear implant with positioner from Advanced Bionics (CLARION). Eight months postoperatively, the patient reported rotatory vertigo and right-side tinnitus after he had blown his nose harder than usual during an episode of rhinitis. Preoperative and postoperative testing of both the petrosal bone with a CT scan and of balance function. Air inclusion in the labyrinth. In contrast to the preoperative high resolution computed tomography (CT) scan, air inclusion was seen in the labyrinth during the episode of vertigo. At the same time, balance function tests with Frenzel glasses revealed both spontaneous and provoked horizontal nystagmus to the right side. At follow-up 8 weeks later, the level of vertigo had significantly decreased. Twelve months later, the control CT showed the cochlear implant positioned correctly and no visible air in the labyrinth. It is known that placement of the HiFocus II with Positioner from CLARION requires a relatively large cochleostomy of 1.5 mm. Moreover, in the connective tissue seal between the electrode and the positioner, the latter reaches into the tympanic cavity, and this is possibly the weak point. Further investigation will be needed to determine whether the large cochleostomy with the HiFocus II with positioner increases the predisposition to labyrinth dysfunction.

1 April 2020 in International Journal of Pediatric Otorhinolaryngology
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KEKatharina Eder
Katharina Eder
MSMaria Elke Schuster
Maria Elke Schuster
Daniel Polterauer-Neuling (née Polterauer)Daniel Polterauer-Neuling (née Polterauer)
Daniel Polterauer-Neuling (née Polterauer)
MNMaike Neuling
Maike Neuling
EHEva Hoster
Eva Hoster
SSSebastian Semmelbauer
Sebastian Semmelbauer

1 August 2016 in Otology & Neurotology
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Journal Article
Closed access
UKUlrich Kisser
Ulrich Kisser
JWJulia Wünsch
Julia Wünsch
JHJohn Martin Hempel
John Martin Hempel
CAChristine Adderson-Kisser
Christine Adderson-Kisser
KSKlaus Stelter
Klaus Stelter
FSFlorian Schrötzlmair
Florian Schrötzlmair
Despite the use of a flexible electrode, complete preservation of low frequency residual hearing can only be achieved in a minority of patients. The use of a full insertion electrode of 28 mm in patients with poor preoperative thresholds does not allow for usable additional hearing at present.