Stefanie Hammersen

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OBJECTIVE Navigation systems enable neurosurgeons to guide operations with imaging data. Sensor-based neuronavigation uses an electromagnetic field and sensors to measure the positions of the patient's brain anatomy and the surgical instruments. The aim of this investigation was to determine the accuracy level of sensor-based tracking in a large patient(More)
OBJECT The use of dural grafts is frequently unavoidable when tension-free dural closure cannot be achieved following neurosurgical procedures or trauma. Biodegradable collagen matrices serve as a scaffold for the regrowth of natural tissue and require no suturing. The aim of this study was to investigate the efficacy and safety of dural repair with a(More)
BACKGROUND The aim of image-guided neurosurgery is to accurately project computed tomography (CT) or magnetic resonance imaging (MRI) data into the operative field for defining anatomical landmarks, pathological structures and tumour margins. To achieve this end, different image-guided and computer-assisted, so-called "neuronavigation" systems have been(More)
BACKGROUND Tracking of post-registration head motion is one of the major problems in frameless stereotaxy. Various attempts in detecting and compensating for this phenomenon rely on a fixed reference device rigidly attached to the patient's head. However, most of such reference tools are either based on an invasive fixation technique or have physical(More)
BACKGROUND Lipomas in the lower spinal canal can lead to progressive neurological deficits, so they may have to be surgically removed. Intraoperative neurophysiological monitoring serves to minimize the morbidity of the surgical procedure. However, so far there are no evidence-based recommendations which type of monitoring procedure or combination of(More)
A 39-year-old man with acquired torticollis suffering from cervicobrachialgia and neurological deficits is presented. Due to a change in head position a transient reproducible tetraplegia and severe vegetative dysfunctions were caused. The origin of this uncommon serious combination of symptoms and signs was a chordoma of the upper cervical spine. After(More)
BACKGROUND Surgical insertion of a ventriculoatrial shunt requires accurate placement of the atrial catheter in the right atrium in order to prevent postoperative complications. Fluoroscopy is the standard method for monitoring correct positioning of the catheter. METHODS This paper reports a prospective study in 50 patients with the aim of comparing(More)
The authors report a case of neuronal ceroid lipofuscinosis (Kufs' disease) confirmed by stereotactically obtained brain biopsy findings and initially diagnosed as a butterfly glioma. The presenting symptoms in the 64-year-old patient were mental alterations with progressive dementia, followed by muscular atrophy and myoclonia with distal preponderance. The(More)
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