A. G. Harders

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While changes in blood velocity in the middle cerebral artery relative to rest were assessed by transcranial Doppler sonography, 70 volunteers with no sign of cerebrovascular disease performed two (left and right middle cerebral artery) series of six cognitive tasks. The tasks are assumed to be processed predominantly by either the left (verbal and(More)
Fifty patients with ruptured aneurysms were operated on within 72 hours after the first subarachnoid hemorrhage (SAH). To prevent symptomatic vasospasm, the patients were given the calcium channel blocker, nimodipine, intravenously (2 mg/hr) for 14 days and orally (60 mg four times daily) for another 7 days. At short intervals (at least every 3rd day) the(More)
STUDY DESIGN A prospective analysis. OBJECTIVE The idea of this study was to evaluate a new miniature robotic system providing passive guidance for pedicle screw placement at the lumbar spine. Special focus was laid on the postoperative accuracy of screw placement. SUMMARY AND BACKGROUND DATA Recent technical developments lead to a minimization of(More)
Seventy volunteers with no sign of cerebral vascular disease performed two series of 6 cognitive tasks, 3 of which are assumed to be processed predominantly by the left and 3 by the right hemisphere. During the tasks, blood flow velocity changes in the middle cerebral artery were recorded every 3 seconds by the transcranial Doppler method (TCD). All tasks(More)
OBJECT Cage subsidence occurs after anterior cervical discectomy and fusion (ACDF). The aim of this prospective study was to evaluate subsidence and total segmental height after implantation of a newly designed Wing titanium cage. Furthermore, alignment of the entire cervical spine was analyzed 2 years after surgery. METHODS Fifty-four patients (26 women(More)
The case of a patient suffering from dural AV malformation in the area of the sigmoid sinus, who had been treated by vascular decompression of the trigeminal nerve ten months previously, is described. Rare examples of AV malformations of the dura are often found in the area of the lateral and sigmoid sinuses. They cause tinnitus synchronous with the pulse,(More)
Reconstruction of craniofacial bone defects by intraoperative modelling of autogenous or alloplastic materials may cause undesirable results concerning the implant shape or the long-term maintenance of this shape. Furthermore, the use of alloplastic materials to be modelled intraoperatively may result in an inflammatory tissue response. Therefore the(More)
The role of the fornix for episodic memory processing is still a matter of controversy. A juvenile patient of average post-surgical intelligence with fornical damage due to tumor removal is described. The fornix was damaged bilaterally at the level of the fornical columns. The patient thereafter suffered major anterograde amnesia which was most pronounced(More)
While the middle cerebral artery (MCA) blood flow velocity changes relative to rest were assessed with transcranial Doppler sonography (TCD), 28 right-handed subjects with no sign of cerebrovascular disease performed two series of 6 cognitive tasks (two series = right and left MCA). The tasks included "reading", "finding nouns with a given first letter",(More)
The reconstruction of craniofacial bone defects with intraoperatively modeled prosthesis restricts the choice of material and its biocompatibility and the prediction of the esthetic result. A prolonged duration of the surgical procedure and an increased stress on the patient are consequences. In contrast, modern industrial CAD/CAM-systems allow the(More)