Biomedical subjects

Oliver Sedlaczek

Publications and source records attributed to Oliver Sedlaczek.

3 recordsLinked to original sources

PubMed2005

Supratentorial age-related white matter changes predict outcome in cerebellar stroke.

BACKGROUND AND PURPOSE: Little is known about the relevance of age related white matter lesions (WMLs) concerning outcome after first-ever territorial stroke. Based on an index patient, we hypothesized that age and pre-existent WMLs rather than infarct volume and topography determine outcome. PATIENTS AND METHODS: Thirty-four consecutive patients with magnetic resonance diffusion-weighted imaging-proven isolated acute cerebellar infarction were prospectively entered on our stroke data registry. Patients with pre-existent neurological deficits, hemorrhagic, or malignant cerebellar infarction were excluded. Patients were stratified using Rankin and Barthel disability scales into groups: I complete recovery, II moderate, and III significant disability 14 days after stroke onset. RESULTS: Initial neurological and functional scores were similar among all the groups with vertigo, nausea, unsteadiness, and limb ataxia being the most common. Infarct volume, vascular territories, and comorbidity did not predict clinical outcome. In contrast, presence and severity of supratentorial WMLs and age significantly determined outcome by functional tests. CONCLUSIONS: In patients with isolated cerebellar infarction functional outcome correlated with the coexistence of age-related WMLs rather than stroke volume and topography. This reflects the loss of compensatory network integrity as the equivalent of functional incapacity beyond local lesion disturbances.

Adult↗

PubMed2005

Transcranial low-frequency ultrasound-mediated thrombolysis in brain ischemia: increased risk of hemorrhage with combined ultrasound and tissue plasminogen activator: results of a phase II clinical trial.

BACKGROUND: Clinical studies using ultrasound at diagnostic frequencies in transcranial Doppler devices provided encouraging results in enhancing thrombolysis with tissue plasminogen activator (tPA) in acute stroke. Low-frequency ultrasound does not require complex positioning procedures, penetrates through the skull better, and has been demonstrated to accelerate thrombolysis with tPA in animal experiments in wide cerebrovascular territories without hemorrhagic side effects. We therefore conducted the first multicenter clinical trial to investigate safety of tPA plus low-frequency ultrasound (300 kHz). METHODS: Acute stroke patients within a 6-hour time window were included (National Institutes of Health Stroke Scale scores >4). Magnetic resonance imaging (MRI) was used to document vascular occlusion and to rule out cerebral hemorrhage. Patients were allocated to combination therapy alternately; the first patient received tPA only, the second patient received tPA plus ultrasound, etc. Follow-up included serial MRI directly thereafter and 24 hours later to confirm recanalization and tissue imaging. Clinical recovery was measured after treatment and 3 months later. RESULTS: 26 patients (70.4+/-9.7 years) entered the trial (12 tPA, 14 tPA plus ultrasound). The study was prematurely stopped because 5 of 12 patients from the tPA only group but 13 of 14 patients treated with the tPA plus ultrasound showed signs of bleeding in MRI (P<0.01). Within 3 days of treatment, 5 symptomatic hemorrhages occurred within the tPA plus ultrasound group. At 3 months, neither morbidity nor treatment-related mortality or recanalization rates differed between both groups. CONCLUSIONS: This study demonstrated bioeffects from low-frequency ultrasound that caused an increased rate of cerebral hemorrhages in patients concomitantly treated with intravenous tPA.

Aged↗

PubMed2005

Diffusion-weighted and perfusion MRI demonstrates parenchymal changes in complex partial status epilepticus.

Diffusion-weighted MRI (DWI) and perfusion MRI (PI) have been mainly applied in acute stroke, but may provide information in the peri-ictal phase in epilepsy patients. Both transient reductions of brain water diffusion, namely a low apparent diffusion coefficient (ADC), and signs of hyperperfusion have been reported in experimental and human epilepsy case studies. We studied 10 patients with complex partial status epilepticus (CPSE) with serial MRI including DWI and PI. All patients showed regional hyperintensity on DWI, and a reduction of the ADC in (i) the hippocampal formation and the pulvinar region of the thalamus (six out of 10 patients), (ii) the pulvinar and cortical regions (two out of 10), (iii) the hippocampal formation only (one out of 10), and (iv) the hippocampal formation, the pulvinar and the cortex (one out of 10). In all patients a close spatial correlation of focal hyperperfusion with areas of ADC/DWI change was present. In two patients hyperperfusion was confirmed in additional SPECT (single photon emission computed tomography) studies. All patients received follow-up MRI examinations showing partial or complete resolution of diffusion and perfusion abnormalities depending on the length of the follow-up interval. The clinical course, EEG and SPECT results all indicate that MRI detected changes related to prolonged epileptic activity. Combined PI and DWI can visualize haemodynamic and tissue changes after CPSE in the hippocampus, thalamus and affected cortical regions.

Adult↗