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Papers by Stefan Hegemann

Swiss Medical Forum ‒ Schweizerisches Medizin-Forum, 2014

INTRODUCTION: Unrealistic optimism refers to the pervasive tendency of healthy individuals to und... more INTRODUCTION: Unrealistic optimism refers to the pervasive tendency of healthy individuals to underestimate their likelihood of future misfortune, including illness. The phenomenon shares a qualitative resemblance with anosognosia, a neurological disorder characterized by a deficient appreciation of manifest current illness or impairment. Unrealistic optimism and anosognosia have been independently associated with a region of right inferior frontal gyrus, the pars opercularis. Moreover, anosognosia is temporarily abolished by vestibular stimulation, particularly by irrigation of the left (but not right) ear with cold water, a procedure known to activate the right inferior frontal region. We therefore hypothesized that left caloric stimulation would attenuate unrealistic optimism in healthy participants. METHODS: Thirty-one healthy right-handed adults underwent cold-water caloric vestibular stimulation of both ears in succession. During each stimulation episode, and at baseline, part...

European Archives of Oto-Rhino-Laryngology

Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo, caused by otoconi... more Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo, caused by otoconia falling from the utricle into a semicircular canal (SCC). After successful repositioning maneuvers residual dizziness (RD) has been described and several reasons are used to explain RD. It can last for only a few days or weeks, but also much longer. We present a patient with a severe traumatic loss of otoconia from both maculae utriculi and a persistent imbalance more than 9 years. We think that the loss of otoconia from the utricular and probably also saccular macula induced a sudden reduction of her ability to sense gravity thus logically explaining her symptoms. We show the vestibular test results also supporting our hypothesis and we extrapolate this support to other forms of so far unexplained dizziness especially increasing imbalance with aging. We also discuss the normal c-and oVEMP indicating intact haircell function and supporting our hypothesis of isolated otoconial loss as the major cause for imbalance.

Nature Precedings

Unrealistic optimism (UO) refers to the tendency of healthy people to underestimate their risk of... more Unrealistic optimism (UO) refers to the tendency of healthy people to underestimate their risk of future misfortune. Just as left-ear caloric irrigation attenuates anosognosia (denial of manifest illness) in clinical patients, we found that it also reduces UO about future health risks in healthy individuals. This finding demonstrates asymmetric hemispheric involvement in emotion regulation and self-evaluation, and suggests that a similar neuropsychological process underpins anosognosia and healthy optimism.

Physiotherapy theory and practice, 2017

This study aimed to analyze the association between prospectively assessed falls and functional a... more This study aimed to analyze the association between prospectively assessed falls and functional abilities in patients with bilateral vestibulopathy (BVP). Nineteen BVP patients had functional abilities assessed at baseline with the expanded timed get-up-and-go (ETGUG) test. Falls were prospectively recorded with a monthly "fall calendar" over a one-year period. Association between baseline functional abilities and falls was evaluated by Mann-Whitney U testing. Logistic regression was applied to describe the relationship between falls and functional abilities. Area under the receiver-operating characteristic curve (AUC) was used predicting falls based on gait speed. Eight (45%) of 18 patients (61.11 ± 15.19 years, 12 male) reported 19 falls. Fallers had a significantly faster preferred gait speed (p = 0.03) in the fifth component of the ETGUG. Preferred gait speed was a significant factor in the prediction of falls model (odds ratio = 2.00, p = 0.05, CI = 1.00/4.00 per 10 c...

Otology & Neurotology, 2017

: The acute vestibular syndrome is a clinically defined entity consisting of vertigo or dizziness... more : The acute vestibular syndrome is a clinically defined entity consisting of vertigo or dizziness that develops acutely over minutes to hours and is accompanied by nausea/vomiting, gait instability, head motion intolerance, and nystagmus, while persisting over a day or more. When it is caused by a peripheral vestibular lesion and is not associated with clinically manifest auditory deficits, it is mostly labeled vestibular neuritis/neuronitis/neuropathy or sometimes peripheral vestibulopathy. Here, we propose hypotheses and discuss current research advances on viral or vascular factors in the pathogenesis, the recurrence, the site of lesion, old and new treatment options, contraindicated measures, the differential diagnosis, and the prognosis of vestibular neuritis/neuronitis/neuropathy or vestibulopathy. Possibly, other structures than the vestibular nerve are also involved in the pathogenetic process and the label peripheral vestibulopathy would be more apt.

Journal of Vestibular Research, 2016

To determine whether patients with acute unilateral peripheral vestibulopathy (PVP), often called... more To determine whether patients with acute unilateral peripheral vestibulopathy (PVP), often called "vestibular neuritis/neuronitis or neuropathy" (VN) have a vestibular lesion pattern consistent with the distribution of the neurological afferents. BACKGROUND: Much is known about the clinical nature of PVP, however less so about its etiology and pathogenesis. Due to the frequency with which VN is used to describe the syndrome, an inflammation of the vestibular nerve or of one of its branches is often assumed to be the cause of PVP, though there is insufficient data so far to support this assumption. METHODS: We conducted a retrospective study of 25 patients who had presented to our clinic with PVP and had all vestibular receptor organs tested shortly after start of symptoms. We analysed their vestibular lesion patterns in order to determine whether they were consistent with the neuritis hypothesis (NH). RESULTS: The lesion patterns varied conspicuously. 76% did not follow an innervation pattern, thereby contradicting the NH and only 24% had a lesion pattern that either definitely (16%) or probably (8%) supported the NH. CONCLUSION: These results should remind us to be careful before jumping to quick conclusions about the pathogenetic nature of PVP. With any reason to question VN as the only cause of PVP, we should reconsider the treatment approach to PVP. If the cause probably or even possibly lies inside the vestibular labyrinth, an intratympanic steroid injection might prove to be a more effective measure, even in first-line treatment. If the etiology is unsure, a combination of systemic and intratympanic steroid treatment may be adequate.

Journal of Vestibular Research, Feb 1, 2004

We present the unique case of a patient with a circumscribed solitary cerebral metastasis of a ma... more We present the unique case of a patient with a circumscribed solitary cerebral metastasis of a malignant melanoma extending from the medial part of the superior temporal gyrus to the lower part of the 1st long insular gyrus causing gait and stance instability and an ipsiversive tilt of the subjective visual vertical. Oculomotor disorders could not be detected. We suggest that the superior temporal gyrus is likely to be involved in spatial orientation presumably using otolithic information.

Oto-rhino-laryngologia Nova, 1993

Background/Aim. Idiopathic sudden sensorineural hearing loss (ISSHL) is one of the most controver... more Background/Aim. Idiopathic sudden sensorineural hearing loss (ISSHL) is one of the most controversial issues in otology. The aim of this study was to determine whether a delay in treatment has any influence on hearing recovery in ISSHL. Method. This study was designed as a retrospective evalua- tion of an electronic patient data base of the University Hos- pital Zürich from

World Neurosurgery, 2016

Embolization of cranial dural sinus arteriovenous fistulae with transvenous occlusion of the invo... more Embolization of cranial dural sinus arteriovenous fistulae with transvenous occlusion of the involved sinuses is an established strategy when the collateral brain drainage allows it. We aimed to investigate the frequency and types of complications after endovascular occlusion of the sigmoid sinus. From our database, we detected 52 endovascularly treated consecutive cases of cranial dural arteriovenous shunts involving the sigmoid sinus. The cases treated through the transvenous approach alone or combined with the transarterial one were analyzed retrospectively. Previously reported series and cases were reviewed and critically analyzed. In 15 cases, a transvenous approach was used and in 4 combined a transvenous approach with a transarterial approach. Two patients (13.3%) both treated with the transvenous approach alone presented postoperatively with vertigo and hearing loss. In the first case, the sinus occlusion involved the whole sigmoid sinus, whereas in the second case the occlusion was restricted to a parallel channel posteriorly to the proximal segment of the sigmoid sinus. Magnetic resonance imaging and ear, nose, and throat investigations failed to elucidate the cause and pathomechanism of these symptoms. No other complications occurred. Although the transvenous occlusion of the sigmoid sinus generally is a safe therapeutic option for the treatment of dural arteriovenous fistulae, inner ear dysfunction is still a possible complication. The combined analysis of the reported and our cases did not allow a plausible explanation of this complication and its pathomechanism remains obscure.

Otol Neurotol, 2008

To aid in realistic counseling of patients at the time of their first visit concerning their chan... more To aid in realistic counseling of patients at the time of their first visit concerning their chances for recovery, we created a simple prognostic model for predicting hearing recovery in idiopathic sudden sensorineural hearing loss (ISSHL). An important element of research on ISSHL is to identify prognostic factors for this disease. Many studies have described predictive indicators to identify patients with a good prognosis needing no or minimal treatment. Only a few of these studies have included a model for calculating the probability for patient recovery, which may be important for clinical work, but these prognostic tables have not achieved widespread use clinically. Evaluation of an electronic patient data base of 541 patients with ISSHL. The standard treatment was carbogen inhalation (95% O2 and 5% CO2 8 times per day in duration of 30 min) and prednisone orally (100 mg in 1 morning dose) for 7 days. Factors that were analyzed included the patient&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s age, the interval between the onset of symptoms and beginning of treatment, the presence or absence of vertigo and tinnitus, audiometric patterns, the severity of hearing loss, and hearing in the opposite ear. Hearing gain was expressed either as absolute hearing gain or as relative hearing gain. Significant recovery of hearing was defined as the final pure-tone audiometry of 30 dB or less (or the same as the pure-tone audiometry of the opposite ear). The absolute hearing gain was 15.1 dB. The mean relative hearing gain was 47%. Three hundred one (57%) patients had significant recovery of hearing, and 228 (43%) did not have significant recovery of hearing. Using step-wise multiple linear regression analysis, the most important factors for prognosis included severity of hearing loss, presence of vertigo, time between onset and treatment, the hearing of the other ear, and the audiogram shape (beta coefficient was -0.216, -0.231, 0.211, 0.113, and -0.064, respectively; constant, 0.968). A recovery expectancy table was developed using the data from this study. Based on a retrospective analysis, prognostic indicators for hearing recovery in ISSHL were found to be severity of hearing loss, presence of vertigo, time between onset and treatment, the hearing of the other ear, and the audiogram shape. We created a model for calculating the probability for hearing recovery based on the analysis of 529 patients with unilateral ISSHL.