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G Wiest

Publications and source records attributed to G Wiest.

At least 19 recordsLinked to original sources
PubMed2006

[Fire-eater's lung. Two cases and review of the literature].

HISTORY AND ADMISSION FINDINGS: Two men were hospitalized (three years apart) after aspirating petroleum on their fist attempt at "fire-eating". Pt.1 (aged 25 years) complained of chest pain, dyspnea and dizziness. The other (Pt. 2; aged 29 years) had a hemoptysis. Pt. 1 had a normal body temperature, but the breath sounds were decreased over the left base. The breath sounds in Pt. 2 were normal, but he had a fever of 38.8 degrees C. Routine physical examination was unremarkable. INVESTIGATIONS: Laboratory tests in both patients revealed increased inflammatory parameters. Chest radiographs showed that Pt. 1 had a left basal alveolar infiltrate, while Pt. 2 had an infiltrate in the right middle and upper lobe, which on computed tomography after a few days showed signs of cavitation in the left infrahilar region and the middle lobe, respectively. Pneumococci were found in the sputum of Pt. 2. TREATMENT AND COURSE: Both patients were given antibiotics, Pt. 1 also had salbutamol inhalation treatment. The patients were discharged symptom-free after 8 and 10 days, respectively. A follow-up chest radiograph four weeks later in Pt. 1 merely showed streaky-fibrotic residues. CONCLUSION: These two case reports and detailed literature search indicate that immediate administration of antibiotics is important, while routine steroid treatment is not necessary.

Administration, Inhalation↗
PubMed2004

Vestibular processing in human paramedian precuneus as shown by electrical cortical stimulation.

The authors describe a 16-year-old patient with recurrent episodes of epileptic linear self-motion perception and occasional body tilts. Intracranial seizure monitoring located the seizure onset, caused by a circumscribed ependymoma, in the right paramedian precuneus. Electrical cortical stimulation of this area could reproduce the same vestibular sensations, which ceased after lesionectomy. The findings implicate the paramedian area of the precuneus in the processing of static and dynamic vestibular, probably otolithic, information.

Adolescent↗
PubMed2001

Cortical responses to object-motion and visually-induced self-motion perception.

We investigated the spatiotemporal cortical dynamics during the perception of object-motion and visually-induced self-motion perception in six normal subjects, using a 143-channel neuromagnetometer. Object-motion specific tasks evoked early transient activity over the right temporooccipital cortex, while self-motion perception, or vection, additionally was followed by sustained bilateral activity in the temporoparietal area. The specific signal distributions suggest to represent the different perceptual modes of object-motion and self-motion sensation.

Adult↗
PubMed2001

Right-sided shift found in metachronous colorectal adenomas.

BACKGROUND AND STUDY AIMS: Patients who have had a colorectal adenoma are likely to develop a metachronous adenoma, and therefore need to be kept under surveillance. The question is whether metachronous adenomas will be found at the same anatomical site as the preceding adenomas, thus prompting us to focus surveillance examinations on this region, using flexible sigmoidoscopy or total colonoscopy. PATIENTS AND METHODS: Between 1978 and 1996 a long-term follow up of 1091 patients was prospectively documented at the Erlangen Registry of Colorectal Polyps. The anatomical sites--distal (rectosigmoid) and proximal colon--of two subsequent generations of metachronous adenomas were analysed using logistic regression analysis. RESULTS: In 556 (51%) patients metachronous adenomas were found during follow up. In 211 (37.9%) of these patients a right-sided shift in the first generation of metachronous adenomas in comparison with initial lesions (P<0.0001) was found. Some 305 patients underwent further follow up, and 51 (27.1%) out of 188 patients with metachronous lesions demonstrated a right-sided shift in their second generation (vs. first generation) of metachronous adenomas. Proximally located first generation metachronous adenomas would be missed by flexible sigmoidoscopy in 50.8% of patients with only distal adenomas at baseline colonoscopy, and in 58.7% of patients with second-generation lesions. Multivariate analysis revealed that multiplicity (odds ratio 2.64, 95% CI 1.49-4.66) and size of initial adenomas (>5 mm) (odds ratio 3.60, 95% CI 1.96-6.66) were significantly associated with a right-sided shift in metachronous adenomas, while female gender was associated with a significantly lower tendency to manifest a right-sided shift (odds ratio of 0.64. 95% CI 0.43-0.94). CONCLUSIONS: Metachronous adenomas are found significantly more often in the right colon than would be expected assuming clustering at the same anatomical site as the preceding lesions. Total colonoscopy is thus needed for surveillance, regardless of the initial adenoma site.

Adenoma↗
PubMed2001

Otolith function in cerebellar ataxia due to mutations in the calcium channel gene CACNA1A.

The vestibulo-ocular reflexes stabilize retinal images during head movements. While there is a wealth of information about the interaction between the cerebellum and vestibulo-ocular reflexes mediated by the semicircular canals, little is known about the role of the cerebellum in the generation of the otolith-mediated linear vestibulo-ocular reflex (LVOR). By means of transient linear acceleration of the whole body along the interaural axis, we examined the LVOR in six patients with hereditary cerebellar ataxia due to mutations of the calcium channel gene CACNA1A, five with spinocerebellar ataxia type 6 (SCA6) and one with episodic ataxia type 2 (EA-2). Six age-matched normal subjects served as controls. Using a peak acceleration of 0.5 g in combination with recording by the binocular scleral magnetic search coil method, it was possible to study the latency and sensitivity of the LVOR in the first 150 ms after motion onset. The normal LVOR showed a significant dependence on viewing distance and covaried with vergence angle, and could be enhanced by the presence of a visible target. In contrast, the LVOR of ataxic patients had normal latency but significantly decreased sensitivity that was not enhanced with visible or nearer targets despite normal vergence. Substituting for the normal smooth LVOR slow phase, ataxic patients employed catch-up saccades 150-250 ms after motion onset. These findings suggest a critical role of the cerebellum in the modulation of otolith-ocular signals that is independent of motor vergence.

Adult↗
PubMed2001

New tests of vestibular function.

The vestibulo-ocular reflex (VOR) is the only drive for short-latency eye movements stabilizing the retina during externally imposed, sudden, high-head accelerations. New strategies can exploit this unique VOR feature to study it under conditions relevant to the daily lives of patients, and to exclude the contributions from confounding nonvestibular mechanisms. Testing of the yaw vestibulo-ocular reflex (VOR) during random, whole-body rotational transients at < or = 2800 degrees/s2 delivered about centered and eccentric axes enables measurement of gains and millisecond latencies of the canal and otolith VORs in humans. Repeated measurements in acute unilateral deafferentation show sequential recovery of canal and otolith VORs to contralesional rotation, but severe and permanent deficits to ipsilesional rotation. Patients with bilateral loss of caloric responses show severe bilateral loss of VORs to transient rotation, suggesting that the apparent preservation of their VORs during sinusoidal rotations at moderate frequencies may be due instead to somatosensory inputs. Since visual acuity is degraded by retinal image motion, dynamic visual acuity (DVA) measured during imposed head-on-body or whole-body transient motion can correlate closely with VOR performance only if optotypes are presented during directionally and temporally unpredictable, high-acceleration head motion. Prediction and efference copy are relentlessly employed by vestibulopathic patients to enable good DVA during predictable or low-acceleration head motion. The linear VOR to transient lateral acceleration is strongly dependent upon viewing distance. The latency of this otolith VOR is slightly longer and more variable than the canal VOR. Unlike the canal VOR, the otolith VOR does not develop a strong directional asymmetry in unilateral deafferentation. The otolith VOR is bilaterally attenuated in bilateral vestibulopathy, and loses target distance dependence in cerebellar degeneration.

Adult↗
PubMed2001

Vestibular function in severe bilateral vestibulopathy.

OBJECTIVES: To assess residual vestibular function in patients with severe bilateral vestibulopathy comparing low frequency sinusoidal rotation with the novel technique of random, high acceleration rotation of the whole body. METHODS: Eye movements were recorded by electro-oculography in darkness during passive, whole body sinusoidal yaw rotations at frequencies between 0.05 and 1.6 Hz in four patients who had absent caloric vestibular responses. These were compared with recordings using magnetic search coils during the first 100 ms after onset of whole body yaw rotation at peak accelerations of 2800 degrees /s(2). Off centre rotations added novel information about otolithic function. RESULTS: Sinusoidal yaw rotations at 0.05 Hz, peak velocity 240 degrees/s yielded minimal responses, with gain (eye velocity/head velocity)<0.02, but gain increased and phase decreased at frequencies between 0.2 and 1.6 Hz in a manner resembling the vestibulo-ocular reflex. By contrast, the patients had profoundly attenuated responses to both centred and eccentric high acceleration transients, representing virtually absent responses to this powerful vestibular stimulus. CONCLUSION: The analysis of the early ocular response to random, high acceleration rotation of the whole body disclosed a profound deficit of semicircular canal and otolith function in patients for whom higher frequency sinusoidal testing was only modestly abnormal. This suggests that the high frequency responses during sinusoidal rotation were of extravestibular origin. Contributions from the somatosensory or central predictor mechanisms, might account for the generation of these responses. Random, transient rotation is better suited than steady state rotation for quantifying vestibular function in vestibulopathic patients.

Adult↗
PubMed2000

Selective loss of vergence control secondary to bilateral paramedian thalamic infarction.

The supranuclear pathways for vergence eye movements are poorly understood. The authors report a 57-year-old patient who presented with selective loss of vergence control and dissociation of light and near reaction. MRI showed a symmetric paramedian thalamic infarction without midbrain lesion. The findings suggest that this syndrome is due to an interruption of supranuclear fibers to midbrain vergence neurons.

Cerebral Infarction↗
PubMed2000

Morphology of coronary atherosclerotic lesions in patients with end-stage renal failure.

BACKGROUND: An excessive rate of cardiac death is a well-known feature of renal failure. Coronary heart disease is frequent and the possibility has been raised that the natural history of the coronary plaque is different in uraemic patients. We assessed the morphology of coronary arteries in patients with end-stage renal failure and compared them with coronary arteries of matched non-uraemic control patients. METHODS: Fifty-four cases were identified at autopsy who met the inclusion criteria: cases, end-stage renal disease (n=27); controls, non-renal patients with coronary artery disease (n=27). At autopsy all three coronary arteries were prepared at corresponding sites for investigations: (i) qualitative analysis (after Stary), (ii) quantitative measurements of intima and media thickness (by planimetry), (iii) immunohistochemical analysis of the coronary plaques and (iv) X-ray diffraction of selected calcified plaques. RESULTS: Qualitative analysis of the coronary arteries showed significantly more calcified plaques of coronary arteries in patients with end-stage renal failure. Plaques of non-uraemic patients were mostly fibroatheromatous. Media thickness of coronary arteries was significantly higher in uraemic patients (187+/-53 microm vs 135+/-29 microm in controls) and intima thickness tended to be higher (158+/-38 microm vs 142+/-31 microm) but this difference was not statistically significant. Plaque area (4.09+/-1. 50 mm(2) vs 4.39+/-0.88 mm(2)) was comparable in both groups. Lumen area, however, was significantly lower in end-stage renal patients. Immunohistochemical analysis of the cellular infiltrate in coronary arteries showed no major differences in these advanced plaques of uraemic and non-uraemic subjects. CONCLUSION: Coronary plaques in patients with end-stage renal failure are characterized by increased media thickness and marked calcification. In contrast to the previous opinion the most marked difference compared to non-uraemic controls does not concern the size, but the composition of the plaque. Deposition of calcium within the plaques may contribute to the high complication rate in uraemic patients.

Aged↗
PubMed2000

Idiothetic orientation and path integration in unilateral hippocampal atrophy and sclerosis.

We determined the effects of hippocampal lesions on idiothetic spatial orientation by exposing 14 patients with unilateral hippocampal atrophy and/or sclerosis (HAS) and 10 normal controls to random rotational displacements (+/-30 degrees -180 degrees ) in darkness and examined their ability to rotate themselves back to the initial position. In comparison to controls, the patients responses were distinctly hypometric (p<0.005). Patients with right hippocampal lesions showed a trend towards higher come back errors p = 0.08). Normal controls could maintain their accuracy over five consecutive trials. Patients, beginning with less accuracy, showed significant improvement after each trial (p<0.001). The findings suggest that unilateral HAS impair the immediate recall of idiothetic spatial information, but does not affect long-term spatial learning.

Adult↗
PubMed1999

Abolished tilt suppression of the vestibulo-ocular reflex caused by a selective uvulo-nodular lesion.

Within the cerebellum several structures are considered to modulate the function of the vestibulo-ocular reflex (VOR). The nodulus and uvula have been implicated with the low-frequency components of the VOR, which are mediated by the velocity storage system. We report a patient with a selective lesion of the nodulus and ventral uvula. The findings suggest that nodulus and uvula normally exert an inhibitory effect on the velocity storage mechanism.

Cerebellum↗
PubMed1997

Ocular flutter and truncal ataxia may be associated with enterovirus infection.

We report on three patients who presented a rare, uniform clinical syndrome consisting of ocular flutter and truncal ataxia. In all patients the symptoms followed an upper respiratory infection and resolved without sequelae within a few weeks. Previous reports have emphasized the apparent relationship of this entity to infectious disease, but the infectious agent remained uncertain. In one patient we could find a significant rise in antibody titres to enterovirus. We are not aware of any other similar documented case.

Adult↗
PubMed1997

[Nasal CPAP therapy of obstructive sleep apnea syndrome with expiratory pressure reduction: a prospective randomized study of acceptance of treatment during therapy initiation].

It is often difficult to achieve adequate acceptance of nasal continuous positive airway pressure (CPAP) therapy by patients with OSA. Many patients find it particularly inconvenient to expire against the treatment pressure. With this in mind, we have attempted to improve acceptance of CPAP therapy by using a bilevel system that reduces the treatment pressure during expiration. 52 patients were randomized either to initial treatment with CPAP therapy followed by bilevel treatment, or to treatment in reversed order. During bilevel therapy the ratio of inspiratory to expiratory pressure was fixed at 1:0.6. After each treatment the patients were interviewed on the basis of visual analogue scales to establish their subjective evaluation of such parameters as general well-being, quality of sleep, comparison of the respective treatment pressures, and possible preference for one of the two systems for long-term treatment. The minimal effective inspiratory treatment pressure during bilevel therapy (IPAP) and the minimal effective CPAP pressure were closely correlated (r = 0.89). There was no difference between the apnoea hypopnoea indices during CPAP therapy as compared with bilevel therapy. Most patients (57%) felt the treatment pressure with the bilevel system to be lower (p = 0.048). There were no differences in patients' well-being early in the morning, or in their assessment of sleep quality. The majority of patients (52%) preferred bilevel therapy for long term treatment, while 38% preferred CPAP therapy (n.s.). In a subgroup of 13 patients with a treatment pressure of > or = 10 mbar during CPAP therapy 10 patients (77%) gave preference to the bilevel system (n.s.). In a considerable number of patients the acceptance of treatment can be improved by using a bilevel system for initiation of nasal positive pressure therapy.

Adult↗
PubMed1996

Monocular elevation paresis and contralateral downgaze paresis from unilateral mesodiencephalic infarction.

A 26 year old woman presented with monocular elevation paresis of the right eye, contralateral paresis of downward gaze, and subtle bilateral ptosis. Magnetic resonance imaging disclosed a unilateral embolic infarction restricted to the mesodiencephalic junction involving the left paramedian thalamus. Preserved vertical oculocephalic movements and intact Bell's phenomenon suggested a supranuclear lesion. This rare "crossed vertical gaze paresis" results from a lesion near the oculomotor nucleus affecting ipsilateral downward gaze and contralateral upward gaze fibres, originating in the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF).

Adult↗
PubMed1996

[Spontaneous and visually-induced oculomotor reactions in microgravity (Results of Austrian-Russian Experiment "Optovert" performed within the frame of program "Austromir", part II)].

Results of investigation of spontaneous and induced by vertical linear and sinusoid optokinetic stimulation oculomotor reactions in short- and long-term space missions are reported. Adaptation to microgravity was shown to be associated with rearrangement in sensory interactions even on a background of good subjective well-being and absence of abnormal autonomous nervous reactions. In the early period of adaptation to microgravity records were made of modified spontaneous oculomotor activity (spontaneous vertical nystagmus) and vertical optokinetic nystagmus (VOKN) including alterations in amplitude and VOKN amplification coefficient.

Adaptation, Ocular↗