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Joachim M. Gilsbach - One of the best experts on this subject based on the ideXlab platform.
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Advanced Neuronavigation in skull base tumors and vascular lesions.
Minimally Invasive Neurosurgery, 2005Co-Authors: Veit Rohde, M H T Reinges, L. Mayfrank, Joachim M. Gilsbach, Peter Spangenberg, Volker A CoenenAbstract:OBJECTIVE: The purpose of this study was to describe the usefulness of recent advances of Neuronavigational technology in the management of skull base tumors and of vascular lesions, treated via a skull base approach. METHODS: In 16 patients (skull base meningioma n = 9, petrous apex epidermoid n = l, craniopharyngeoma n = 1, giant internal carotid artery aneurysm n = 1, basilar/vertebral artery aneurysm n = 2, brain stem cavernoma n = 2), "advanced" Neuronavigation was used. In contrast to "conventional" Neuronavigation, the information for the neurosurgeon was enhanced by the intraoperative screen display of 3-dimensional reconstructions of the lesion, vessels, nerves and fiber tracts at risk. The 3-dimensional reconstructions were obtained by preoperative manual or automated segmentation processes. In addition, different imaging modalities (computed tomography [CT] with magnetic resonance imaging [MRI], CT with CT angiography, T (l)- with diffusion-weighted MRI) were fused and shown on the screen. RESULTS: In the cases of tumors, "advanced" Neuronavigation facilitated the approach (n = 4), contributed to tailor the approach (n = 2) and helped to identify hidden neurovascular structures (n = 9). In the cases of aneurysms, "advanced" Neuronavigation allowed us to reduce the skull base approach to the needs of safe aneurysm clipping (n = 3). In both cases of brain stem cavernoma, "advanced" Neuronavigation was deemed useful for definition of the best surgical approach in relation to the pyramidal tract and brain stem nuclei. CONCLUSION: The authors' experiences suggest that Neuronavigation, which displays 3-dimensional reconstructions of lesion, vessels, nerves and fiber tracts during surgery and makes use of image fusion techniques, is an important tool in the neurosurgical management of skull base lesions.
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Error analysis in cranial Neuronavigation.
Minimally Invasive Neurosurgery, 2002Co-Authors: Uwe Spetzger, M H T Reinges, Joachim M. Gilsbach, Timo Krings, Ulrich Hubbe, T. Struffert, Gabriele A. Krombach, Josef Zentner, H.s. StiehlAbstract:: Neuronavigation systems are now an important component of many modern neurosurgical treatment strategies. Their support facilities intraoperative orientation and makes neurosurgical operations more precise and less traumatic. Computer-aided neurosurgery is definitively not a temporary fashionable phenomenon, the concept of Neuronavigation is here to stay. This report summarizes a ten-years-long experience and presents an error analysis of 108 failures (12.4 %) in a total of 874 image-guided cranial neurosurgical procedures with an arm-linked (mechanical) system and two different infrared-light emitting (optical) systems. The application of Neuronavigation incurs multiple reasons for pitfalls because of the complex man-machine interface. Principally, we have to differentiate two types of errors: "machine made errors" due to soft- or hardware failure and "man made errors" generally, due to inadequate handling of the navigation system. The error analysis demonstrated that the so-called human interface plays the main role causing a high error rate.
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Three-dimensional visualization of the pyramidal tract in a Neuronavigation system during brain tumor surgery: First experiences and technical note
Neurosurgery, 2001Co-Authors: Volker A Coenen, M H T Reinges, L. Mayfrank, Richard S. Polin, Timo Krings, Armin Thron, Joachim M. GilsbachAbstract:OBJECTIVE: To integrate spatial three-dimensional information concerning the pyramidal tracts into a customized system for frameless Neuronavigation during brain tumor surgery. METHODS: Four consecutive patients with intracranial tumors in eloquent areas underwent diffusion-weighted and anatomic magnetic resonance imaging studies within 48 hours before surgery. Diffusion-weighted datasets were merged with anatomic data for navigation purposes. The pyramidal tracts were segmented and reconstructed for three-dimensional visualization. The reconstruction results, together with the fused-image dataset, were available during surgery in the environment of a customized Neuronavigation system. RESULTS: In all four patients, the combination of reconstructed data and fused images was a helpful additional source of information concerning the tumor seat and topographical interaction with the pyramidal tract. In two patients, intraoperative motor cortex stimulation verified the tumor seat with regard to the precentral gyrus. CONCLUSION: Diffusion-weighted magnetic resonance imaging allows individual estimation of large fiber tracts applicable as important information in intraoperative Neuronavigation and in planning brain tumor resection. A three-dimensional representation of fibers associated with the pyramidal tract during brain tumor surgery is feasible with the presented technique and is a helpful adjunct for the neurosurgeon. The main drawbacks include the length of time required for the segmentation procedure, the lack of direct intraoperative control of the pyramidal tract position, and brain shift. However, mapping of large fiber tracts and its intraoperative use for Neuronavigation have the potential to increase the safety of neurosurgical procedures and to reduce surgical morbidity.
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Interactive graphical anatomical Neuronavigation: past, present and future of 3D image guided neurosurgery
IECON '98. Proceedings of the 24th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.98CH36200), 1998Co-Authors: U. Spetzger, M H T Reinges, Timo Krings, T. Struffert, M. Schreckenberger, K. Niemann, Joachim M. GilsbachAbstract:Today, modern Neuronavigation systems achieve a computer-controlled direct between preoperative radiological and individual intraoperative anatomy. The authors' experiences in over 400 image-guided neurosurgical procedures with an arm-linked (mechanical) system and an infrared-light (optical) system demonstrate that Neuronavigation enables precise pre- and intraoperative planning and improves surgical orientation. This technological support facilitates neurosurgical operations and results in a reduction of surgical trauma, improving the postoperative outcome and the quality of life of the patient. The future generation of Neuronavigation systems will match structural and functional data in an overlay technique to inaugurate a new dimension of brain mapping.
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frameless Neuronavigation in modern neurosurgery
Minimally Invasive Neurosurgery, 1995Co-Authors: U. Spetzger, G Laborde, Joachim M. GilsbachAbstract:: A fundamental effort in neurosurgery is to reduce surgical trauma. Microneurosurgical technique combined with precise localization of lesions, can minimize the invasiveness of neurosurgical procedures. This report summarizes the utility of frameless neuronavigator systems and examines their value in reducing operative invasiveness. The basic principle of Neuronavigation is the virtual linkage between digitized neuroradiological data and real anatomical structures, allowing an excellent three-dimensional orientation by real-time graphic-anatomic interaction. As frameless graphic interactive Neuronavigation is developed further, these devices should become an important component of the modern microneurosurgical armamentarium and reduce surgical morbidity.
Hiroshi Iseki - One of the best experts on this subject based on the ideXlab platform.
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identification of the pyramidal tract by Neuronavigation based on intraoperative diffusion weighted imaging combined with subcortical stimulation
Stereotactic and Functional Neurosurgery, 2009Co-Authors: Norihiko Ozawa, Yoshihiro Muragaki, Ryoichi Nakamura, Hiroshi IsekiAbstract:BACKGROUND/AIMS: To identify the pyramidal tract by Neuronavigation based on intraoperative diffusion-weighted imaging (iDWI) combined with subcortical stimulation. METHODS: Seven patients with brain tumors near the deep white matter underwent resection surgery using Neuronavigation based on iDWI to visualize white matter bundles. Subcortical electrical stimulation was performed and electromyography was measured at the extremities when surgical manipulation came near the position corresponding to the depicted bundle. We validated the bundle depicted on iDWI by considering the responses to subcortical stimulation and the distance between the stimulation site and the depicted bundle. RESULTS: Positive motor-evoked potentials were detected in 5 of 7 patients (8 stimulations) and the distance from the stimulation site to the depicted bundle was 0-4.7 mm (mean +/- SD, 1.4 +/- 2.1 mm). Negative (no) responses were obtained in all patients when the distance was more than 5 mm. The Neuronavigation system had an average error of 0.79 +/- 0.25 mm and a maximum error of 2.0 mm (n = 16). CONCLUSION: Neuronavigation based on iDWI combined with subcortical stimulation allowed surgeons to identify the pyramidal tract and avoid inadvertent injury. Our findings demonstrate that the white matter bundles depicted by iDWI can contain the pyramidal tract.
Volker A Coenen - One of the best experts on this subject based on the ideXlab platform.
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Advanced Neuronavigation in skull base tumors and vascular lesions.
Minimally Invasive Neurosurgery, 2005Co-Authors: Veit Rohde, M H T Reinges, L. Mayfrank, Joachim M. Gilsbach, Peter Spangenberg, Volker A CoenenAbstract:OBJECTIVE: The purpose of this study was to describe the usefulness of recent advances of Neuronavigational technology in the management of skull base tumors and of vascular lesions, treated via a skull base approach. METHODS: In 16 patients (skull base meningioma n = 9, petrous apex epidermoid n = l, craniopharyngeoma n = 1, giant internal carotid artery aneurysm n = 1, basilar/vertebral artery aneurysm n = 2, brain stem cavernoma n = 2), "advanced" Neuronavigation was used. In contrast to "conventional" Neuronavigation, the information for the neurosurgeon was enhanced by the intraoperative screen display of 3-dimensional reconstructions of the lesion, vessels, nerves and fiber tracts at risk. The 3-dimensional reconstructions were obtained by preoperative manual or automated segmentation processes. In addition, different imaging modalities (computed tomography [CT] with magnetic resonance imaging [MRI], CT with CT angiography, T (l)- with diffusion-weighted MRI) were fused and shown on the screen. RESULTS: In the cases of tumors, "advanced" Neuronavigation facilitated the approach (n = 4), contributed to tailor the approach (n = 2) and helped to identify hidden neurovascular structures (n = 9). In the cases of aneurysms, "advanced" Neuronavigation allowed us to reduce the skull base approach to the needs of safe aneurysm clipping (n = 3). In both cases of brain stem cavernoma, "advanced" Neuronavigation was deemed useful for definition of the best surgical approach in relation to the pyramidal tract and brain stem nuclei. CONCLUSION: The authors' experiences suggest that Neuronavigation, which displays 3-dimensional reconstructions of lesion, vessels, nerves and fiber tracts during surgery and makes use of image fusion techniques, is an important tool in the neurosurgical management of skull base lesions.
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Three-dimensional visualization of the pyramidal tract in a Neuronavigation system during brain tumor surgery: First experiences and technical note
Neurosurgery, 2001Co-Authors: Volker A Coenen, M H T Reinges, L. Mayfrank, Richard S. Polin, Timo Krings, Armin Thron, Joachim M. GilsbachAbstract:OBJECTIVE: To integrate spatial three-dimensional information concerning the pyramidal tracts into a customized system for frameless Neuronavigation during brain tumor surgery. METHODS: Four consecutive patients with intracranial tumors in eloquent areas underwent diffusion-weighted and anatomic magnetic resonance imaging studies within 48 hours before surgery. Diffusion-weighted datasets were merged with anatomic data for navigation purposes. The pyramidal tracts were segmented and reconstructed for three-dimensional visualization. The reconstruction results, together with the fused-image dataset, were available during surgery in the environment of a customized Neuronavigation system. RESULTS: In all four patients, the combination of reconstructed data and fused images was a helpful additional source of information concerning the tumor seat and topographical interaction with the pyramidal tract. In two patients, intraoperative motor cortex stimulation verified the tumor seat with regard to the precentral gyrus. CONCLUSION: Diffusion-weighted magnetic resonance imaging allows individual estimation of large fiber tracts applicable as important information in intraoperative Neuronavigation and in planning brain tumor resection. A three-dimensional representation of fibers associated with the pyramidal tract during brain tumor surgery is feasible with the presented technique and is a helpful adjunct for the neurosurgeon. The main drawbacks include the length of time required for the segmentation procedure, the lack of direct intraoperative control of the pyramidal tract position, and brain shift. However, mapping of large fiber tracts and its intraoperative use for Neuronavigation have the potential to increase the safety of neurosurgical procedures and to reduce surgical morbidity.
Rudolf Fahlbusch - One of the best experts on this subject based on the ideXlab platform.
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Intraoperative Image-Guided Surgery of the Lateral and Anterior Skull Base in Patients with Tumors or Trauma.
Skull Base Surgery, 2004Co-Authors: Joerg Wiltfang, Rudolf Fahlbusch, Oliver Ganslandt, Christopher Nimsky, Stephan Rupprecht, P. Keßler, Stefan Schultze-mosgau, Friedrich Wilhelm NeukamAbstract:The aim of this investigation was to evaluate the suitability and usefulness of the Stealth Station™ intraoperative guiding system (Medtronic Sofamor Danek, Memphis, TN) in a variety of indications. Eleven intraoperative image–guided procedures were performed for anterior or lateral skull base lesions. The most common neurosurgical approaches included frontal, coronal, and parietotemporal access. Neuronavigation reliably allowed the extent of tumor configuration and risk zones (e.g., blood vessels) to be visualized. Thus, gross tumor resection was achieved in 6 of 7 patients and facilitated reconstruction by the maxillofacial surgeon, resulting in radiologically symmetrical and clinically satisfying results. Postoperatively, one patient was blind from a continuity defect of the optic nerve caused by a bone fragment. Despite destruction of anatomical landmarks related to tumor invasion or intraoperative bone removal, Neuronavigation proved helpful in the reconstruction of bony structures. Overall, the use of Neuronavigation in interdisciplinary surgery for complicated tumors or trauma of the anterior or lateral skull base allows more radical resection associated with less morbidity.
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Neuronavigation concept techniques and applications
Neurology India, 2002Co-Authors: Oliver Ganslandt, Rudolf Fahlbusch, S Behari, J Gralla, Christopher NimskyAbstract:Neuronavigation provides intraoperative orientation to the surgeon, helps in planning a precise surgical approach to the targetted lesion and defines the surrounding neurovascular structures. Incorporation of the functional data provided by functional MRI and magnetoencephalography (MEG) with Neuronavigation helps to avoid the eloquent areas of the brain during surgery. An intraoperative MRI enables radical resection of the lesions, the possibility of immediate control for tumor remnants and updates of Neuronavigation with intraoperative images to compensate for brain shift. In this study, the experience of 432 patients undergoing Neuronavigation assisted neurosurgical interventions using either the pointer-based or microscope-based navigational systems at the University of Erlangen-Nuremberg, Germany is presented. The procedures included stereotactic biopsy (n=53), stereotactic cyst puncture/ventricular drainage (n=15), eloquent cortex/tumor localization to facilitate tumor resection, assessment of neurovascular structures in the vicinity of tumors of the sellar-suprasellar regions, skull base, posterior fossa and ventricular region (n=252), and, surgery for epilepsy (n=9). Functional brain mapping using fMRI and MEG and their integration with Neuronavigation was carried out in 24 and 128 patients respectively. The simultaneous use of intraoperative MRI to look for the remaining tumor was done in 159 patients and the update of navigational data was carried out in 17 patients. The mean system accuracy obtained by using both the fiducial registration as well as anatomical landmark-surface fitting computer algorithm was 1.81 mm. This study reviews the relative merits and demerits of the pointer and microscope based navigational systems and also highlights the role of functional brain mapping and intraoperative MRI, when integrated with Neuronavigation, in the surgical decision-making to offer the chances of more radical resections with minimal morbidity.
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intraoperative magnetic resonance imaging combined with Neuronavigation a new concept
Neurosurgery, 2001Co-Authors: Christopher Nimsky, Oliver Ganslandt, H Kober, Michael Buchfelder, Rudolf FahlbuschAbstract:OBJECTIVE: Intraoperative image data may be used not only to evaluate the extent of a tumor resection but also to update Neuronavigation, compensating for brain shift. To date, however, intraoperative magnetic resonance imaging (MRI) can be combined only with navigation microscopes that are separated from the magnetic field, thus requiring time-consuming intraoperative patient transport. To help solve this problem, we investigated whether a new navigation microscope can be used within the fringe field of the MRI scanner. METHODS: The navigation microscope was placed at the 5-G line of a 0.2 MRI device. Patients were positioned lying down directly on the table of the scanner, with their heads placed approximately 1.5 m from the center of the magnet, fixed in an MRI-compatible ceramic head holder. Standard operating instruments were used. For intraoperative imaging, we slid the table into the center of the magnet in less than 30 seconds. RESULTS: By use of this setup, we operated on 22 patients. In all patients, anatomic Neuronavigation could be used in combination with intraoperative MRI. In addition, in 12 patients, functional data from magnetoencephalographic or functional MRI studies were integrated, resulting in functional Neuronavigation. We did not encounter adverse effects of the low magnetic field during navigation. Moreover, intraoperative imaging was not disturbed by the navigation microscope and vice versa. CONCLUSION: Functional Neuronavigation and intraoperative MRI can be used essentially simultaneously without the need for lengthy intraoperative patient transport. The combination of intraoperative imaging with functional Neuronavigation offers the opportunity for more radical resections and fewer complications.
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intraoperative imaging with open magnetic resonance imaging and Neuronavigation
Childs Nervous System, 2000Co-Authors: Rudolf Fahlbusch, Oliver Ganslandt, Christopher NimskyAbstract:The Erlangen-concept of image-guided-surgery is based on the installation of an open magnetic resonance (MR) scanner (Magnetom Open, 0.2 T, Siemens AG) in a twin operating room in combination with two Neuronavigation systems (Stealth NeuroStation, Sofamor Danek, MKM Zeiss). Since March 1996 this method has been used for a total of 402 patients, among them 44 children. In 214 patients, mainly with gliomas or pituitary adenomas or who needed surgery for epilepsy, we performed intraoperative MR imaging to monitor the extent of resection, allowing a second look for possible tumor remnants and also compensating for brain shift by an intraoperative update of Neuronavigation. Functional Neuronavigation, i.e. the combination of anatomical Neuronavigation with functional imaging [e.g. magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI)] was used in patients with lesions in brain areas such as the motor and speech areas. For MEG we used a MAGNES II biomagnetometer (Biomagnetic Technologies, San Diego, Calif.) and for fMRI a 1.5 T Siemens Symphony MR scanner. So far we have treated 89 patients with functional Neuronavigation. Our preliminary experience indicates that intraoperative MR imaging, especially in combination with functional Neuronavigation, allows more radical resections with lower morbidity.
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functional Neuronavigation with magnetoencephalography outcome in 50 patients with lesions around the motor cortex
Journal of Neurosurgery, 1999Co-Authors: Oliver Ganslandt, Rudolf Fahlbusch, Christopher Nimsky, H Kober, Martin Moller, Ralf Steinmeier, J Romstock, J ViethAbstract:Object. The authors conducted a study to evaluate the clinical outcome in 50 patients with lesions around the motor cortex who underwent surgery in which functional Neuronavigation was performed. Methods. The sensorimotor cortex was identified in all patients with the use of magnetoencephalography (MEG). The MEG-source localizations were superimposed onto a three-dimensional magnetic resonance image and the image data set was implemented into a Neuronavigation system. Based on this setup, the surgeon chose the best surgical strategy. During surgery, the pre- and postcentral gyri were identified by Neuronavigation and, in addition, the central sulcus was localized using intraoperative recording of somatosensory evoked potentials. In all cases MEG localizations of the sensory or motor cortex were correct. In 30% of the patients preoperative paresis improved, in 66% no additional deficits occurred, and in only 4% (two patients) deterioration of neurological function occurred. In one of these patients the det...
Hidenao Fukuyama - One of the best experts on this subject based on the ideXlab platform.
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clinical impact of integrated functional Neuronavigation and subcortical electrical stimulation to preserve motor function during resection of brain tumors
Journal of Neurosurgery, 2007Co-Authors: Nobuhiro Mikuni, Tsutomu Okada, Rei Enatsu, Yukio Miki, Takashi Hanakawa, Shinichi Urayama, Kenichiro Kikuta, Jun A Takahashi, Kazuhiko Nozaki, Hidenao FukuyamaAbstract:Object. The authors evaluated the clinical impact of combining functional Neuronavigation with subcortical electrical stimulation to preserve motor function following the removal of brain tumors. Methods. Forty patients underwent surgery for treatment of brain tumors located near pyramidal tracts that had been identified by fiber tracking. The distances between the electrically stimulated white matter and the pyramidal tracts were measured intraoperatively with tractography-integrated functional Neuronavigation, and correlated with subcortical motor evoked potentials (MEPs) and clinical symptoms during and after resection of the tumors. Motor function was preserved after appropriate tumor resection in all cases. In 18 of 20 patients, MEPs were elicited from the subcortex within 1 cm of the pyramidal tracts as measured using intraoperative Neuronavigation. During resection, improvement of motor weakness was observed in two patients, whereas transient mild motor weakness occurred in two other patients. In 20 patients, the distances between the stimulated subcortex and the estimated pyramidal tracts were more than 1 cm, and MEPs were detected in only three of these patients following stimulation. Conclusions. Intraoperative functional Neuronavigation and subcortical electrical stimulation are complementary techniques that may facilitate the preservation of pyramidal tracts around 1 cm of resected tumors.