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Sabine Fitzek

Publications and source records attributed to Sabine Fitzek.

13 recordsLinked to original sources

Levetiracetam as a treatment option in non-convulsive status epilepticus.

Non-convulsive status epilepticus (NCSE) is characterized by continuous or recurrent, generalized or focal epileptiform activity on the electroencephalogram and diverse clinical symptoms with alterations of mental state and vigilance. NCSE is not rare but certainly under diagnosed. There is some debate about how aggressive NCSE should be treated, as high dose anticonvulsants maybe partially responsible for the morbidity and mortality of patients with NCSE. We hypothesized that levetiracetam (LEV) as a well tolerated, highly effective new anticonvulsant, may be a safe treatment option. We retrospectively analyzed all (8) patients with NCSE who received levetiracetam from our database, compared with 11 patients with NCSE treated with conventional intravenous status medication as controls. These eight patients showed a marked clinical improvement with final cessation of ictal EEG-activity and clinical symptoms of NCSE after initiation of LEV within 3 days (mean 1.5 days). The response to conventional treatment was similarly effective but there were severe side effects whereas no relevant side effects in the LEV-treated group were noticed. A long-term follow up (6-36 months from discharge) revealed six patients with a persisting reduction in seizure frequency on medication with LEV. One patient changed the anticonvulsive medication because of inefficacy and one died from other causes than epilepsy 2 months after discharge from hospital. We found no significant differences in hospitalisation time, time in intensive care unit and outcome between the LEV group and the control group. This retrospectively acquired data suggests that LEV may be a well tolerated, effective treatment option in NCSE. This highlights the need for a prospective controlled study to further elucidate the utility of LEV in the treatment of NCSE, particularly as an intravenous formulation is now available.

Aged↗

Valproic acid induced encephalopathy--19 new cases in Germany from 1994 to 2003--a side effect associated to VPA-therapy not only in young children.

Valproic acid (VPA) is a broad-spectrum antiepileptic drug and is usually well-tolerated. Rare serious complications may occur in some patients, including haemorrhagic pancreatitis, bone marrow suppression, VPA-induced hepatotoxicity and VPA-induced encephalopathy. The typical signs of VPA-induced encephalopathy are impaired consciousness, sometimes marked EEG background slowing, increased seizure frequency, with or without hyperammonemia. There is still no proof of causative effect of VPA in patients with encephalopathy, but only of an association with an assumed causal relation. We report 19 patients with VPA-associated encephalopathy in Germany from the years 1994 to 2003, none of whom had been published previously.

Adolescent↗

Valproic acid-induced hepatopathy: nine new fatalities in Germany from 1994 to 2003.

PURPOSE: Valproic acid (VPA) is an antiepileptic drug (AED) commonly used for generalized and focal epilepsies. We provide an update on hepatotoxic side effects in Germany between 1994 and 2003. METHODS: We mailed a questionnaire to all members of the German Section of the International League Against Epilepsy, asking for VPA-induced side effects, especially severe side effects such as hepatopathy. RESULTS: As a result of our questionnaire, we found 31 cases of reversible hepatotoxicity and nine cases of lethal hepatopathies in Germany from 1994 to 2003. CONCLUSIONS: The outcome of patients with severe hepatotoxicity is better than that in the past. The risk of a VPA-induced hepatopathy is not limited to patients younger than 2 years, receiving polytherapy, or patients with congenital or acquired metabolic diseases.

Adolescent↗

Somatotopic organization of the corticospinal tract in the human brainstem: a MRI-based mapping analysis.

To investigate the incompletely understood somatotopical organization of the corticospinal tract in the human brainstem, we performed a voxel-based statistical analysis of standardized magnetic resonance scans of 41 prospectively recruited patients with pyramidal tract dysfunction caused by acute brainstem infarction. Motor hemiparesis was rated clinically and by the investigation of motor evoked potentials to arms and legs. Infarction affected the pons in 85% of cases. We found the greatest level of significance of affected brainstem areas between the pontomesencephalic junction and the mid pons. Lesion location was significantly more dorsal in patients with hemiparesis affecting more proximal muscles and was significantly more ventral in patients with predominantly distal limb paresis. Comparison of magnetic resonance lesion from patients with paresis predominantly affecting arm or leg did not show significant topographical differences. We conclude that a topographical arm/leg distribution of corticospinal fibers is abruptly broken down as the descending corticospinal tract traverses the pons. Corticospinal fibers, however, follow a somatotopical order in the pons with fibers controlling proximal muscles being located close to the reticular formation in the dorsal pontine base, and thus more dorsal than the fibers controlling further distal muscle groups.

Adult↗

Anisotropy of human linea alba: a biomechanical study.

BACKGROUND: Recently, a new model of fiber architecture of the linea alba has been described consisting of an oblique fiber layer of intermingling oblique fibers, a transverse fiber layer containing mainly transverse fibril bundles, and a variable, small irregular fiber layer. In this study the morphological model was proven using direction-specific biomechanical measurements of the linea alba. MATERIAL AND METHODS: Thirty-one human abdominal walls were analyzed (16 male and 15 female). Six strips of collagen tissue with a width of 1 cm were exsected from each linea alba transversely, obliquely, and longitudinally according to the main fiber directions. An increasing force from 2 to 24 N was applied to these strips, and the corresponding strain represented by the relative elongation was measured, which allows the calculation of a direction-specific compliance of the tissue. RESULTS: The compliance is highest in longitudinal and smallest in transverse direction. In the infraumbilical part of the female linea alba the compliance was significantly smaller in the transverse direction than in the oblique direction. Moreover, the compliance in the transverse direction was significantly smaller in women than in men. CONCLUSIONS: A distinct anisotropy of morphological and biomechanical properties was demonstrated as well as sex-dependent differences. The compliance correlates with the distribution of fiber orientation in the linea alba. These biomechanical results constitute the functional correlation with the fiber morphology of the linea alba and correspond well to our earlier proposed model of fiber architecture.

Abdominal Muscles↗

Organic bipolar disorder occurring together with spontaneous intracranial hypotension.

Spontaneous intracranial hypotension (SIH) is known to cause postural headache, often combined with auditory, and vestibular symptoms, nausea, vomiting, and diplopia. We report a 63-year-old male patient who for the first time developed a depressive episode followed by acute manic symptoms during the course of SIH, both relieved after treatment of the underlying organic disturbance.

Bipolar Disorder↗

Event-related fMRI with painful electrical stimulation of the trigeminal nerve.

Several functional brain imaging studies of pain using positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) have shown that painful stimulation causes activation of different brain areas. The aim of the present study was to develop and implement painful stimulation of the trigeminal nerve, which can be applied with event-related paradigms by using MRI. Twelve healthy, right-handed volunteers were examined. Painful electrical stimulation of the first trigeminal branch was performed. In an event-related setting with a 1.5 T clinical scanner with EPI capability, the following fMRI parameters were used: 20 slices, 3 mm thickness, isotropic voxel, 306 measurements with 54 randomized events. Statistical postprocessing was performed with SPM99. Activation of the ipsi- and contralateral secondary somatosensory cortex (SII), and the contralateral insular cortex was observed as well as a contralateral thalamic activation (T=4.45, extension 15 voxels). Six of the 12 volunteers revealed also activation of the cingulate cortex. The investigation demonstrates that painful stimulation of the trigeminal nerve activates the contralateral insular cortex, SII, and thalamus, as well as the ipsilateral SII. In contrast to other studies, the cingulate cortex was only activated inconsistently.

Adult↗

Bilateral Wallerian degeneration of the medial cerebellar peduncles after ponto-mesencephalic infarction.

Three patients with acute large paramedian ponto-mesencephalic infarctions developed a bilateral retrograde degeneration of the medial cerebellar peduncles within 4 months after the insult. In an initial magnetic resonance imaging (MRI) within the first 2 weeks, the medial cerebellar peduncles showed normal intensities, but a control MRI after 4 months showed bright hyperintensities in the T2-TSE weighted images, and moderately increased signal intensities in echo planar imaging-diffusion weighted imaging were seen, possibly representing bilateral Wallerian degeneration of the cerebellar-pontine fibers.

Aged↗

Cortical vestibular representation in the superior temporal gyrus.

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.

Brain Neoplasms↗

Diffusion-weighted MRI of cholesteatomas of the petrous bone.

PURPOSE: To investigate if primary cholesteatomas of the petrous bone show high signal in diffusion-weighted imaging (DWI). MATERIALS AND METHODS: In this blinded study, we compared 15 patients with clinically certain cases and later surgically proven cholesteatomas vs. 12 patients with clinically acute otitis of the middle ear and 20 volunteers without petrous bone disease. Two blinded readers without knowledge of the clinical data decided in consensus agreement whether there was a pathologic signal increase in the petrous bone in an anisotropic single-shot echo-planar imaging (EPI) DWI sequence, an artifact, or no signal increase. RESULTS: Thirteen of 15 patients with cholesteatomas showed bright signal in EPI DWI, whereas 10 of 12 patients with acute otitis media and all volunteers presented the usual low signal of petrous bone. CONCLUSION: EPI DWI is a fast diagnostic method that may be an additional valuable tool in the workup of suspected cholesteatomas. The ability of this technique to differentiate between cholesteatomas and granulomas or chronic otitis is not yet available.

Artifacts↗

Electrophysiological brainstem testing in the diagnosis of reversible brainstem ischemia.

The aim of this study was to evaluate the sensitivity of multimodal electrophysiological brainstem testing in the diagnosis of clinically suspected reversible ischemic deficits of the brainstem compared with diffusion weighted MR imaging. We investigated 158 consecutive patients presenting with signs of acute brainstem dysfunction. Serial electrophysiological brainstem tests including masseter reflex, blink reflex, masseter inhibitory reflex, AEP, MEP, EOG and the oculoauricular phenomenon were applied. In 14 of the 158 patients neurological deficits resolved in less than 24 hours, which was suggestive of a transitory ischemic attack (TIA), 19 patients had brainstem signs for more than 24 hours but less than 1 week, suggestive of a reversible ischemic neurological deficit (RIND). Electrophysiological data indicated acute functional brainstem lesions in 54,5 % of patients with transient clinical brainstem impairment. Lesion detection rate was significantly higher when combining electrophysiological data and MRI (60,4 %) than using acute brainstem abnormalities in diffusion weighted MRI alone (39,4 %). We conclude that diffusion weighted MRI and electrophysiological brainstem testing are complimentary sensitive indicators of acute brainstem lesions in patients with reversible neurological deficits. Correct identification of brainstem ischemia influences the therapeutic regimen and may improve patient outcome.

Adult↗