Johannes Gerb

Dr. Johannes Gerb

Ludwig-Maximilians-Universität München, Munich, Bavaria, Germany
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Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

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

Representative Publications

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11 March 2021 in Frontiers in Neurology
Verified
Journal Article
Open access
SOSunyoung Oh
Sunyoung Oh
MDMarianne Dieterich
Marianne Dieterich
BLBit Na Lee
Bit Na Lee
RBRainer Boegle
Rainer Boegle
JKJin-Ju Kang
Jin-Ju Kang
VKValerie Kirsch
Valerie Kirsch
Objective: Intravenous contrast agent enhanced, high-resolution magnetic resonance imaging of the inner ear (iMRI) confirmed that patients with Menière's disease (MD) and vestibular migraine (VM) could present with endolymphatic hydrops (EH). The present study aimed to investigate EH characteristics and their interrelation to neurotologic testing in patients with VM, MD, or VM with concurrent MD (VM-MD).Methods: Sixty–two patients (45 females, aged 23–81 years) with definite or probable VM (n = 25, 19 definite), MD (n = 29, 17 definite), or showing characteristics of both diseases (n = 8) were included in this study. Diagnostic workup included neurotologic assessments including video-oculography (VOG) during caloric stimulation and head-impulse test (HIT), ocular and cervical vestibular evoked myogenic potentials (o/cVEMP), pure tone audiometry (PTA), as well as iMRI. EH's degree was assessed visually and via volumetric quantification using a probabilistic atlas-based segmentation of the bony labyrinth and volumetric local thresholding (VOLT).Results: Although a relevant number of VM patients reported varying auditory symptoms (13 of 25, 52.0%), EH in VM was only observed twice. In contrast, EH in VM-MD was prevalent (2/8, 25%) and in MD frequent [23/29, 79.3%; χ2(2) = 29.1, p < 0.001, φ = 0.7]. Location and laterality of EH and neurophysiological testing classifications were highly associated (Fisher exact test, p < 0.005). In MD, visual semi-quantitative grading and volumetric quantification correlated highly to each other (rS = 0.8, p < 0.005, two-sided) and to side differences in VOG during caloric irrigation (vestibular EH ipsilateral: rS = 0.6, p < 0.05, two-sided). In VM, correlations were less pronounced. VM-MD assumed an intermediate position between VM and MD.Conclusion: Cochlear and vestibular hydrops can occur in MD and VM patients with auditory symptoms; this suggests inner ear damage irrespective of the diagnosis of MD or VM. The EH grades often correlated with auditory symptoms such as hearing impairment and tinnitus. Further research is required to uncover whether migraine is one causative factor of EH or whether EH in VM patients with auditory symptoms suggests an additional pathology due to MD.

1 August 2023 in JAMA Neurology
Verified
Journal Article
Closed access
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MSMichael Strupp
Michael Strupp
MMMarco Mandala
Marco Mandala
AVAnne-Sophie Vinck
Anne-Sophie Vinck
LBLaure Van Breda
Laure Van Breda
LSLorenzo Salerni
Lorenzo Salerni
NGNicolina Goldschagg
Nicolina Goldschagg
Importance: Questions remain concerning treatment efficacy for the common condition of benign paroxysmal positional vertigo (BPPV).Objective: To compare the effectiveness of the Semont-plus maneuver (SM-plus) and the Epley maneuver (EM) for treatment of posterior canal benign paroxysmal positional vertigo (pcBPPV) canalolithiasis.Design, Setting, and Participants: This prospective randomized clinical trial was performed at 3 national referral centers (in Munich, Germany; Siena, Italy; and Bruges, Belgium) over 2 years, with a follow-up to 4 weeks after the initial examination. Recruitment took place from June 1, 2020, until March 10, 2022. Patients were selected randomly during routine outpatient care after being referred to 1 of the 3 centers. Two hundred fifty-three patients were assessed for eligibility. After consideration of the exclusion criteria as well as informed consent, 56 patients were excluded and 2 declined to participate, with 195 participants included in the final analysis. The analysis was prespecified and per-protocol.Interventions: After being randomized to the SM-plus or the EM group, patients received 1 initial maneuver from a physician, then subsequently performed self-maneuvers at home 3 times in the morning, 3 times at noon, and 3 times in the evening.Main Outcome and Measures: Patients had to document whether they could provoke positional vertigo every morning. The primary end point was the number of days until no positional vertigo could be induced on 3 consecutive mornings. The secondary end point was the effect of the single maneuver performed by the physician.Results: Of the 195 participants included in the analysis, the mean (SD) age was 62.6 (13.9) years, and 125 (64.1%) were women. The mean (SD) time until no positional vertigo attacks could be induced in the SM-plus group was 2.0 (1.6) days (median, 1 [range, 1-8] day; 95% CI, 1.64-2.28 days); in the EM group, 3.3 (3.6) days (median, 2 [range, 1-20] days; 95% CI, 2.62-4.06 days) (P = .01; α = .05, 2-tailed Mann-Whitney test). For the secondary end point (effect of a single maneuver), no significant difference was detected (67 of 98 [68.4%] vs 61 of 97 [62.9%]; P = .42; α = .05). No serious adverse event was detected with both maneuvers. Nineteen patients (19.6%) in the EM group and 24 (24.5%) in the SM-plus group experienced relevant nausea.Conclusions and Relevance: The SM-plus self-maneuver is superior to the EM self-maneuver in terms of the number of days until recovery in pcBPPV.Trial Registration: ClinicalTrials.gov Identifier: NCT05853328

14 July 2020 in Journal of Neurology
Verified
Journal Article
Open access
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Johannes GerbJohannes Gerb
Johannes Gerb
SAS. A. Ahmadi
S. A. Ahmadi
EKE. Kierig
E. Kierig
BEB. Ertl-Wagner
B. Ertl-Wagner
MDM. Dieterich
M. Dieterich
VKV. Kirsch
V. Kirsch
Background: Objective and volumetric quantification is a necessary step in the assessment and comparison of endolymphatic hydrops (ELH) results. Here, we introduce a novel tool for automatic volumetric segmentation of the endolymphatic space (ELS) for ELH detection in delayed intravenous gadolinium-enhanced magnetic resonance imaging of inner ear (iMRI) data. Methods: The core component is a novel algorithm based on Volumetric Local Thresholding (VOLT). The study included three different data sets: a real-world data set (D1) to develop the novel ELH detection algorithm and two validating data sets, one artificial (D2) and one entirely unseen prospective real-world data set (D3). D1 included 210 inner ears of 105 patients (50 male; mean age 50.4 ± 17.1 years), and D3 included 20 inner ears of 10 patients (5 male; mean age 46.8 ± 14.4 years) with episodic vertigo attacks of different etiology. D1 and D3 did not differ significantly concerning age, gender, the grade of ELH, or data quality. As an artificial data set, D2 provided a known ground truth and consisted of an 8-bit cuboid volume using the same voxel-size and grid as real-world data with different sized cylindrical and cuboid-shaped cutouts (signal) whose grayscale values matched the real-world data set D1 (mean 68.7 ± 7.8; range 48.9–92.8). The evaluation included segmentation accuracy using the Sørensen-Dice overlap coefficient and segmentation precision by comparing the volume of the ELS. Results: VOLT resulted in a high level of performance and accuracy in comparison with the respective gold standard. In the case of the artificial data set, VOLT outperformed the gold standard in higher noise levels. Data processing steps are fully automated and run without further user input in less than 60 s. ELS volume measured by automatic segmentation correlated significantly with the clinical grading of the ELS (p < 0.01). Conclusion: VOLT enables an open-source reproducible, reliable, and automatic volumetric quantification of the inner ears’ fluid space using MR volumetric assessment of endolymphatic hydrops. This tool constitutes an important step towards comparable and systematic big data analyses of the ELS in patients with the frequent syndrome of episodic vertigo attacks. A generic version of our three-dimensional thresholding algorithm has been made available to the scientific community via GitHub as an ImageJ-plugin.

22 April 2021 in Frontiers in Neurology
Verified
Journal Article
Open access
RBRainer Boegle
Rainer Boegle
Johannes GerbJohannes Gerb
Johannes Gerb
EKEmilie Kierig
Emilie Kierig
SBSandra Becker-Bense
Sandra Becker-Bense
BEBirgit Ertl-Wagner
Birgit Ertl-Wagner
VKValerie Kirsch
Valerie Kirsch
In-vivonon-invasive verification of endolymphatic hydrops (ELH) by means of intravenous delayed gadolinium (Gd) enhanced magnetic resonance imaging of the inner ear (iMRI) is rapidly developing into a standard clinical tool to investigate peripheral vestibulo-cochlear syndromes. In this context, methodological comparative studies providing standardization and comparability between labs seem even more important, but so far very few are available. One hundred eight participants [75 patients with Meniere's disease (MD; 55.2 ± 14.9 years) and 33 vestibular healthy controls (HC; 46.4 ± 15.6 years)] were examined. The aim was to understand (i) how variations in acquisition protocols influence endolymphatic space (ELS) MR-signals; (ii) how ELS quantification methods correlate to each other or clinical data; and finally, (iii) how ELS extent influences MR-signals. Diagnostics included neuro-otological assessment, video-oculography during caloric stimulation, head-impulse test, audiometry, and iMRI. Data analysis provided semi-quantitative (SQ) visual grading and automatic algorithmic quantitative segmentation of ELS area [2D, mm2] and volume [3D, mm3] using deep learning-based segmentation and volumetric local thresholding. Within the range of 0.1–0.2 mmol/kg Gd dosage and a 4 h ± 30 min time delay, SQ grading and 2D- or 3D-quantifications were independent of signal intensity (SI) and signal-to-noise ratio (SNR; FWE corrected,p< 0.05). The ELS quantification methods used were highly reproducible across raters or thresholds and correlated strongly (0.3–0.8). However, 3D-quantifications showed the least variability. Asymmetry indices and normalized ELH proved the most useful for predicting quantitative clinical data. ELH size influenced SI (cochlear basal turnp< 0.001), but not SNR. SI could not predict the presence of ELH. In conclusion, (1) Gd dosage of 0.1–0.2 mmol/kg after 4 h ± 30 min time delay suffices for ELS quantification. (2) A consensus is needed on a clinical SQ grading classification including a standardized level of evaluation reconstructed to anatomical fixpoints. (3) 3D-quantification methods of the ELS are best suited for correlations with clinical variables and should include both ears and ELS values reported relative or normalized to size. (4) The presence of ELH increases signal intensity in the basal cochlear turn weakly, but cannot predict the presence of ELH.

13 September 2024 in Journal of Neurology, Neurosurgery & Psychiatry
Verified
Journal Article
Open access
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VKValerie Kirsch
Valerie Kirsch
RBRainer Boegle
Rainer Boegle
Johannes GerbJohannes Gerb
Johannes Gerb
EKEmilie Kierig
Emilie Kierig
BEBirgit B Ertl-Wagner
Birgit B Ertl-Wagner
Marianne DieterichMarianne Dieterich
Marianne Dieterich
Background: Vestibular migraine (VM), the most frequent episodic vertigo, is difficult to distinguish from Ménière’s disease (MD) because reliable biomarkers are missing. The classical proof of MD was an endolymphatic hydrops (EH). However, a few intravenous gadolinium-enhanced MRI studies of the inner ear (iMRI) also revealed an EH in VM. The major questions were the frequency and distribution characteristics of EH in VM for diagnostic use.Methods: In a prospective case-control study of 200 participants, 75 patients with VM (49 females; mean age 46 years) and 75 with MD (36 females; mean age 55 years), according to the Bárány and International Headache Society, and 50 age-matched participants with normal vestibulocochlear testing (HP), were enrolled. Analyses ofiMRI of the endolymphatic space included volumetric quantification, stepwise regression, correlation with neurotological parameters and support vector machine classification.Results: EH was maximal in MD (80%), less in VM (32%) and minimal in HP (22%). EH was milder in VM (mean grade 0.3) compared with MD (mean grade 1.3). The intralabyrinthine distribution was preferably found in the vestibulum in VM, but mainly in the cochlea in MD. There was no interaural lateralisation of EH in VM but in the affected ear in MD. The grade of EH in the vestibulum was correlated in both conditions with the frequency and duration of the attacks.Conclusion: Three features of theiMRI evaluation were most supportive for the diagnosis of VM at group and individual levels: (1) the bilateral manifestation, (2) the low-grade EH and (3) the intraaural distribution.

8 March 2022 in Journal of Neurology
Verified
Journal Article
Open access
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Johannes GerbJohannes Gerb
Johannes Gerb
TBT. Brandt
T. Brandt
Marianne DieterichMarianne Dieterich
Marianne Dieterich
Deficits in spatial memory, orientation, and navigation are often early or neglected signs of degenerative and vestibular neurological disorders. A simple and reliable bedside test of these functions would be extremely relevant for diagnostic routine. Pointing at targets in the 3D environment is a basic well-trained common sensorimotor ability that provides a suitable measure. We here describe a smartphone-based pointing device using the built-in inertial sensors for analysis of pointing performance in azimuth and polar spatial coordinates. Interpretation of the vectors measured in this way is not trivial, since the individuals tested may use at least two different strategies: first, they may perform the task in an egocentric eye-based reference system by aligning the fingertip with the target retinotopically or second, by aligning the stretched arm and the index finger with the visual line of sight in allocentric world-based coordinates similar to using a rifle. The two strategies result in considerable differences of target coordinates. A pilot test with a further developed design of the device and an app for a standardized bedside utilization in five healthy volunteers revealed an overall mean deviation of less than 5° between the measured and the true coordinates. Future investigations of neurological patients comparing their performance before and after changes in body position (chair rotation) may allow differentiation of distinct orientational deficits in peripheral (vestibulopathy) or central (hippocampal or cortical) disorders.