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OBJECTIVES The authors aimed at investigating the occurrence of depression and the level of quality of life in patients with amyotrophic lateral sclerosis (ALS), an incurable neurodegenerative disease leading to progressive motor paralysis. They further wished to elucidate correlates of depression and quality of life, such as physical impairment, time since(More)
OBJECTIVE To evaluate the duration of benefit on symptoms, quality of life, and survival derived from the use of noninvasive positive-pressure ventilation by patients with amyotrophic lateral sclerosis. DESIGN In this prospective, cohort study, 30 of 36 consecutively referred symptomatic patients tolerated nightly noninvasive positive-pressure ventilation(More)
For many navigated surgical procedures, the precise registration of preoperative data sets with bones of the patient is an important requisite. Conventional navigation systems use paired point registration based on anatomical landmarks or fiducial markers. This approach increases the invasiveness, since landmarks must be exposed and fiducial markers must be(More)
We developed a fast and robust algorithm to register intraoperative three dimensional ultrasound data of the spine with preoperative CT data. We compared different gradient based and evolutionary optimization strategies for solving the registration problem. The iRprop, a fast gradient based optimization algorithm, quickly and reliably led to higher(More)
We studied the effects of transcranial magnetic stimulation (TMS) on slow cortical potentials (SCPs) of the brain elicited during performance of a feedback and reward task. Ten healthy participants were trained to self-regulate their SCP amplitude using visual feedback and reward for increased or decreased amplitudes. Subjects participated in 27 runs (each(More)
Recent work has demonstrated the accuracy and operational viability of an algorithm proposed by the authors that successfully registers 3-D ultrasound data with CT or MRI data. The successful application of this method to intraoperative navigation, however, depends critically on the quality of the acquired ultrasound data. This gives rise to two questions(More)
Zusammenfassung. Ein zentrales Problem in der bildgestützten, na-vigierten Chirurgie ist die exakte Registrierung präoperativer CT/MR-Daten im Koordinatensystem des Operationssaales. Um die Nachteile einer landmarkenbasierten Registrierung zu umgehen, dient bei unse-rem Ansatz 3-dimensionaler, intraoperativer Ultraschall zur Registrie-rung. Ein(More)
An algorithm for the registration of bones in three-dimensional CT-and ultrasound-datasets, based on surface-volume-matching, is tested in vitro with respect to its accuracy. A point-registration based on fiducial markers is used as a reference for the measurements. The comparison of ultrasound-und point-registration shows maximal deviations of up to 1.7 mm(More)