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Publications (4)5.55 Total impact

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    ABSTRACT: Ultrasound harmonic imaging of perfusion after ultrasound contrast agent (UCA) bolus injection (BHI) can detect cerebral perfusion deficits. In a pilot study, we evaluated the ability of time-intensity curve (TIC) measurements to differentiate between normal and hypoperfused brain areas in acute ischemic stroke. Ten patients with symptoms of acute middle cerebral artery infarction were investigated (SONOS 5500, Harmonic Imaging 1.6/3.8 MHz, diencephalic plane, 10 cm investigation depth, SonoVue 2.4 mL bolus). Peak signal increase (PSI), time-to-peak intensity (TPI) and area under the curve (AUC) were calculated for 60 regions-of-interest (ROIs) in each patient. Reference methods: Perfusion- and diffusion-weighted MRI (PWI/DWI) within 4 h before/after BHI (PWI threshold: 4 s). Receiver operating characteristics (ROC) analysis defined cut-off values for each TIC variable to distinguish between normal and affected brain areas as defined by PWI/DWI. In five patients, PWI showed a perfusion delay >4 s; seven patients had a DWI lesion. In three patients, both PWI and DWI findings showed pathology; one patient had a normal MRI of the insonation plane. Cut-off values for PWI delay: PSI: 5.53% (sensitivity .98, specificity .89); TPI: 4.04 s (sensitivity .74, specificity .69) and AUC: .63 (sensitivity .94, specificity .58). Referred to the mean value in unaffected brain areas the relative thresholds were 17.6%, 109.5% and 16.1%, respectively. Regarding DWI, only for PSI, a significant cut-off value was defined: 10.86%, sensitivity .84, specificity .60 (34.6% of mean). In conclusion, these thresholds distinguish between normal and affected brain areas in acute ischemic stroke.
    Ultrasound in Medicine & Biology 06/2007; 33(6):851-6. · 2.46 Impact Factor
  • Aktuelle Neurologie - AKTUEL NEUROL. 01/2006; 33.
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    ABSTRACT: Hemicraniectomy as a surgical treatment for intracranial pressure following large ischemic lesions is widely practiced in selected patients. The antiphospholipid antibody syndrome (APS), a disorder characterized by recurrent arterial and venous thrombosis, is a very rare cause of space occupying ischemic lesions. We present a case of a 35 year old female diagnosed with APS who initially presented with small ischemic lesions and within days developed a massive near-total infarction of the right hemisphere. Because of central nervous system, skin and systemic manifestations Sneddon's syndrome and catastrophic antiphospholipid antibody syndrome (CAPS) remained a possible diagnoses. Sneddon's syndrome is a non-inflammatory occlusive arteriopathy of small and medium size arteries predominantly of the skin and brain, whereas the catastrophic antiphospholipid antibody syndrome is characterized by acute multi-organ system thrombosis of small and large vessels. In addition to the diagnostic criteria for APS a heterozygous factor V Leiden mutation was found in this patient, which may be a contributing risk factor for cerebral ischemia. When considering invasive decompressive procedures the neurosurgeon has to be aware of the poor prognosis of some forms of APS with systemic manifestations.
    Acta Neurochirurgica 10/2005; 147(9):997-1002; discussion 1002. · 1.55 Impact Factor
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    ABSTRACT: We present an unusual case of cerebellar haemorrhage followed by tension pneumocephalus several days after thoracotomy for resection of a Pancoast tumour. The postoperative course of the 32-year-old patient was complicated by a cerebellar haemorrhage and hydrocephalus caused by compression of the fourth ventricle. Immediate surgical evacuation of the haemorrhage and placement of an external ventricular drain was performed. Respirator ventilation maintaining a continuous positive airway pressure was required. Following weaning and extubation the patient rapidly deteriorated and became comatose. A cranial CT scan revealed a dilated ventricular system filled with air, and air in the subarachnoid space. Recovery of consciousness was observed after aspiration of intracranial air through the ventricular drainage. Recurrent deterioration of consciousness after repeated air aspiration indicated rapid refilling of the ventricles with air. The patient underwent emergency surgical re-exploration of the thoracic resection cavity: dural lacerations of the cervico-thoracic nerve roots C8 and Th1 were identified. Subarachnoid-pleural fistula, cerebellar haemorrhage and tension pneumocephalus after discontinuation of continuous positive airway pressure respiration are unusual complications of thoracic surgery. We discuss the putative pathomechanisms and present a brief review of the literature.
    Acta Neurochirurgica 06/2005; 147(5):561-4;discussion 564. · 1.55 Impact Factor