Showing papers on "Neuronavigation published in 2003"
TL;DR: onavigation provides real-time information during tumor removal in alignment with the preoperative magnetic resonance imaging scans, thus enabling the surgeon to detect intraoperative hemorrhage, cyst drainage, and tumor resection, and it allows for calculation of brain shift during the use of standard navigation techniques.
Abstract: OBJECTIVE: Sononavigation, which combines real-time anatomic ultrasound data with neuronavigation techniques, is a potentially valuable adjunct during the surgical excision of brain tumors. METHODS: In this study, we report our preliminary observations using this technology on 58 adult patients harboring hemispheric tumors. Data regarding coregistration accuracy was collected from various landmarks that typically do not shift as well as from tumor boundaries and the cortical surface. in a subset of patients, we evaluated the extent and direction of postresection brain displacement and its relationship with patient age, tumor histology, tumor volume, and use of mannitol. RESULTS: For all structures excluding the cortex, average coregistration accuracy measurements between ultrasound and preoperatively acquired magnetic resonance imaging scans were within the range of 2 mm. The most accurate alignments were obtained with the choroid plexus and the falx, and the least reliable structure in terms of coregistration accuracy was the cortical surface. CONCLUSION: Sononavigation provides real-time information during tumor removal in alignment with the preoperative magnetic resonance imaging scans, thus enabling the surgeon to detect intraoperative hernorrnage, cyst drainage, and tumor resection, and it allows for calculation of brain shift during the use of standard navigation techniques.
86 citations
TL;DR: The proposed functional neuronavigation allows neurosurgeons to perform effective and maximal resection of brain lesions, identifying and sparing eloquent cortical components and their subcortical connections.
75 citations
TL;DR: Neuronavigation can be applied during endonasal transsphenoidal endoscopic surgery and requires a minimal amount of time, which makes reoperation easier, faster, and probably safer.
Abstract: OBJECTIVE To assess the role that neuronavigation plays in assisting endoscopic transsphenoidal reoperations for recurrent pituitary adenomas. METHODS During a 45-month period, 19 endoscopic endonasal transsphenoidal reoperations were performed for recurrent pituitary adenomas. In 11 of 19 patients, the procedure was performed with the aid of an optically guided system. Clinical records were reviewed retrospectively, with attention to the following: comparison of baseline clinical data, the duration of surgery, and the postoperative course and complications of both image-guided and non-image-guided endoscopic reoperations. In addition, to test the reliability of the neuronavigation system, we made measurements of intraoperative accuracy in five additional transnasal endoscopic procedures in "virgin" noses and sphenoidal sinuses. RESULTS In both groups studied, we found no difference with regard to either morbidity or mortality, which were null. The mean setup time was 13 minutes shorter in non-image-guided procedures (P = 0.021), and the operative time was 36 minutes shorter in image-guided procedures (P = 0.038). No other statistically significant differences were found between the two groups. In all cases, we found that the system performed without malfunction. Continuous information regarding instrument location and trajectory was provided to the surgeon. Measurements of the intraoperative accuracy in the axial, coronal, and sagittal planes indicated a mean intraoperatively verified system error of 1.6 +/- 0.6 mm. CONCLUSION Neuronavigation can be applied during endonasal transsphenoidal endoscopic surgery and requires a minimal amount of time. It makes reoperation easier, faster, and probably safer.
70 citations
TL;DR: Investigation of alternative ways to integrate intraoperative 3D ultrasound images and preoperative MR images in the same 3D scene for visualizing brain shift and improving overview and interpretation in ultrasound-based neuronavigation showed that in 50% of the cases there were indications of brain shift even before the surgical procedure had started.
Abstract: Objective: We have investigated alternative ways to integrate intraoperative 3D ultrasound images and preoperative MR images in the same 3D scene for visualizing brain shift and improving overview and interpretation in ultrasound-based neuronavigation.Materials and Methods: A Multi-Modal Volume Visualizer (MMW) was developed that can read data exported from the SonoWand® neuronavigation system and reconstruct the spatial relationship between the volumes available at any given time during an operation, thus enabling the exploration of new ways to fuse pre-and intraoperative data for planning, guidance and therapy control. In addition, the mismatch between MRI volumes registered to the patient and intraoperative ultrasound acquired from the dura was qualified.Results: The results show that image fusion of intraoperative ultrasound images in combination with preoperative MRI will make perception of available information easier by providing updated (real-time) image information and an extended overview of the...
70 citations
TL;DR: Intraoperative high-field MRI allows a reliable delineation of the extent of resection in glioma surgery, and offers increased image quality and a much broader spectrum of different imaging modalities, compared to previous intraoperative low-field systems.
Abstract: Objective. To apply a new setup, combining the benefits of high-field magnetic resonance imaging (MRI) with microscope-based neuronavigation, providing anatomical and functional guidance, in glioma surgery.
69 citations
TL;DR: Intraoperative PTV on the basis of ADW provides the neurosurgeon with reliable information concerning the position of the principal motor pathways during intracranial procedures as proved with intraoperative electrophysiological testing and has the potential to reduce operative morbidity.
67 citations
TL;DR: The additional information provided by fMRI, particularly when incorporated into a neuronavigation guided craniotomy, was deemed highly valuable to the neurosurgeon as it enabled safe resection of tumour in anatomical locations previously deemed to be too high risk for safe resections using conventional (non-fMRI-guided) technique.
Abstract: Functional MRI (fMRI) may provide a means of locating areas of eloquent cortex that can be used to guide neurosurgeons in their quest to maximize intracerebral tumour resection whilst minimizing post-procedural neurological deficits. This work aimed to develop and provide an initial assessment of such a technique. 19 patients with mass lesions close to the primary motor cortex underwent fMRI at 1.5T. A single shot echo planar technique was used to acquire data corresponding to right and left hand movement. Resultant activation maps were used to aid pre-surgical planning. Data was used in conjunction with an intraoperative navigation system in 13 cases. Activation was attributed to primary motor, primary somatosensory or supplementary motor cortex in 17 of 19 subjects. No permanent changes in motor deficit were detected post surgery. The additional information provided by fMRI, particularly when incorporated into a neuronavigation guided craniotomy, was deemed highly valuable to the neurosurgeon as it enabled safe resection of tumour in anatomical locations previously deemed to be too high risk for safe resection using conventional (non-fMRI-guided) technique. This observation is reinforced by the fact that no patients suffered permanent neurological deficit after radical tumour debulking (surgical estimates >90% tumour resection).
66 citations
TL;DR: A more radical tumor resection - evaluated by postoperative MRI - was achieved in the study group (p = 0.04) and also a trend toward a better neurological outcome and a comparison with a control group that was operated on in the authors' service when the combination of these monitoring techniques was not available.
Abstract: The purpose of this study was to achieve a more radical resection of tumors in the area of the motor cortex via minimal craniotomy using a combination of neuronavigation and neurophysiological monitoring with direct electrical cortical stimulation and to compare retrospectively the clinical outcome and postoperative magnetic resonance imaging with a control group that was operated on in our service when the combination of these monitoring techniques was not available. A total of 42 patients with tumors in or near the central region underwent surgery with neuronavigation guidance and neurophysiological monitoring. The primary motor cortex was identified intraoperatively by the somatosensory evoked phase reversal method and direct cortical stimulation. The functional areas were transferred into the neuronavigation system. By stimulating the identified primary motor cortex and displaying the motor area in the operating microscope a permanent control of the motor function was possible during the whole operation. Using these techniques a more radical tumor resection - evaluated by postoperative MRI - was achieved in the study group (p = 0.04) and also a trend toward a better neurological outcome.
56 citations
TL;DR: Intraoperative MR imaging offers the possibility of further tumour removal during the same surgical procedure in case of tumour remnants, increasing the rate of complete tumours removal.
Abstract: Objective. To give an overview on intraoperative magnetic resonance (MR) imaging in glioma surgery.
56 citations
TL;DR: Neuronavigation is a useful tool for planning and performing a transoral approach that optimizes preoperative planning, clarifies and secures resection limits, and reduces overall surgical morbidity.
Abstract: OBJECTIVE The transoral approach is an elegant reliable surgical procedure that provides anterior exposure of the cranial base and the craniocervical junction. Our objective was to demonstrate the advantages of neuronavigation in planning and performing the transoral approach. METHODS Three patients with chordomas and one patient with rheumatoid atlantoaxial subluxation were considered for a neuronavigated transoral procedure. For image guidance, the Stryker navigation system (Stryker Instruments, Kalamazoo, MI) was used. Registration was performed with individually constructed occlusal splints with four markers. RESULTS The transoral approach was successfully used for two patients with chordomas involving the cranial base and the upper spine and for one patient with dislocation of the dens and medullary compression. In one case, preoperative simulation of the approach and trajectory planning demonstrated that adequate resection could not be achieved via the transoral route, and a paracondylar suboccipital approach was used. The registration accuracy achieved with the occlusal splint was less than 1 mm. CONCLUSION Neuronavigation is a useful tool for planning and performing a transoral approach. It optimizes preoperative planning, clarifies and secures resection limits, and reduces overall surgical morbidity. Registration with an occlusal splint with four markers proved to be an attractive alternative to conventional systems.
51 citations
TL;DR: A method that brings together three essential technologies for surgery planning and guidance: neuronavigation systems, 3D visualization techniques and intraoperative 3D imaging technologies is demonstrated.
Abstract: Objective This paper demonstrates a method that brings together three essential technologies for surgery planning and guidance: neuronavigation systems, 3D visualization techniques and intraoperative 3D imaging technologies. We demonstrate the practical use of an in-house interactive stereoscopic visualization module that is integrated with a 3D ultrasound based neuronavigation system. Materials and methods A stereoscopy volume visualization module has been integrated with a 3D ultrasound based neuronavigation system, which also can read preoperative MR and CT data. The various stereoscopic display modalities, such as "cut plane visualization" and "interactive stereoscopic tool guidance" are controlled by a pointer, a surgical tool or an ultrasound probe. Interactive stereoscopy was tested in clinical feasibility case studies for planning and guidance of surgery procedures. Results By orientating the stereoscopic projections in accordance to the position of the patient on the operating table, it is easier to interpret complex 3D anatomy and to directly take advantage of this 3D information for planning and surgical guidance. In the clinical case studies, we experienced that the probe-controlled cut plane visualization was promising during tumor resection. By combining 2D and 3D display, interpretation of both detailed and geometric information may be achieved simultaneously. The possibilities of interactively guiding tools in a stereoscopic scene seemed to be a promising functionality for use during vascular surgery, due to specific location of certain vessels. Conclusion Interactive stereoscopic visualization improves perception and enhances the ability to understand complex 3D anatomy. The practical benefit of 3D display is increased considerably when integrated with surgical navigation systems, since the orientation of the stereoscopic projection corresponds to the orientation of the patient on the operating table. Stereoscopic visualizations work well on MR and CT images, although volume rendering techniques are especially suitable for intraoperative 3D ultrasound image data.
TL;DR: In this paper, the authors used a frameless stereotactic system (BrainLab AG, Munich, Germany) to estimate the distal sylvian fissure and find the exact site for insular corticotomy.
Abstract: OBJECTIVE Surgical treatment of cavernomas arising in the insula is especially challenging because of the proximity to the internal capsule and lenticulostriate arteries. We present our technique of image guidance for operations on insular cavernomas and assess its clinical usefulness. METHODS Between 1997 and 2003, with the guidance of a frameless stereotactic system (BrainLab AG, Munich, Germany), we operated on eight patients who harbored an insular cavernoma. Neuronavigation was used for 1) accurate planning of the craniotomy, 2) identification of the distal sylvian fissure, and, finally, 3) finding the exact site for insular corticotomy. Postoperative clinical and neuroradiological evaluations were performed in each patient. RESULTS The navigation system worked properly in all eight neurosurgical patients. Exact planning of the approach and determination of the ideal trajectory of dissection toward the cavernoma was possible in every patient. All cavernomas were readily identified and completely removed by use of microsurgical techniques. No surgical complications occurred, and the postoperative course was uneventful in all patients. CONCLUSION Image guidance during surgery for insular cavernomas provides high accuracy for lesion targeting and permits excellent anatomic orientation. Accordingly, safe exposure can be obtained because of a tailored dissection of the sylvian fissure and minimal insular corticotomy.
TL;DR: The study indicates that the application of neuronavigation allows surgery on supratentorial cavernous hemangiomas in critical brain areas with low morbidity and the intraoperative MR resection control ensures a complete resection and illustrates the minimal invasive approach.
Abstract: In a retrospective study the postoperative results of 26 patients operated on for supratentorial cavernous hemangiomas either deep-seated or near eloquent brain areas are summarized. An exact surgical approach to these lesions is essential to prevent neurological deterioration. Three different navigation systems were used and compared according to their clinical applicability. Complete removal of the lesion was obtained in all patients of this series. In six cases (23 %) functional data from magnetoencephalography or functional magnetic resonance imaging were integrated into the navigational setup. In 14 cases (54 %) intraoperative magnetic resonance imaging was performed. The follow-up time was 3 - 26 months (mean: 10 months). In the postoperative course one patient (3.8 %) developed a hemiparesis, another one developed quadrantopia. Nineteen patients presented with preoperative seizure history, 16 of these (84 %) had no further or rare seizures after surgery. The better results in seizure control were achieved in those patients with shorter duration of seizure history before surgery. The study indicates that the application of neuronavigation allows surgery on supratentorial cavernous hemangiomas in critical brain areas with low morbidity. The intraoperative visualization of eloquent cortex areas by integration of functional data allows a fast identification and exemption of eloquent brain areas, preventing neurological deterioration. Furthermore, the intraoperative MR resection control ensures a complete resection and illustrates the minimal invasive approach.
TL;DR: The authors present their experience with the first 80 consecutive patients who received anesthesia in a specially designed radio frequency‐shielded operating room equipped with a high‐field (1.5 T) MR scanner, which provides the use of total intravenous anesthesia with propofol and remifentanil allowing rapid extubation and neurologic examination following surgery.
Abstract: Intraoperative magnetic resonance imaging (MRI) has been used for years to update neuronavigation and for intraoperative resection control. For this purpose, low-field (0.1-0.2 T) MR scanners have been installed in the operating room, which, in contrast to machines using higher magnetic field strength, allowed the use of standard anesthetic and surgical equipment. However, these low-field MR systems provided only minor image quality and a limited battery of MR sequences, excluding functional MRI, diffusion-weighted MRI, or MR angiography and spectroscopy. Based on these advantages, a concept using high-field MRI (1.5 T) with intraoperative functional neuronavigational guidance has been developed that required adaptation of the anesthetic regimen to working in the close vicinity to the strong magnetic field. In this paper the authors present their experience with the first 80 consecutive patients who received anesthesia in a specially designed radio frequency-shielded operating room equipped with a high-field (1.5 T) MR scanner. We describe the MR-compatible anesthesia equipment used including ventilator, monitoring, and syringe pumps, which allow standard neuroanesthesia in this new and challenging environment. This equipment provides the use of total intravenous anesthesia with propofol and remifentanil allowing rapid extubation and neurologic examination following surgery. In addition, extended intraoperative monitoring including EEG monitoring required for intracranial surgery is possible. Moreover, problems and dangers related to the effects of the strong magnetic field are discussed.
Journal Article•
TL;DR: Hypothalamic hamartoma presents with precocious puberty, epilepsy or both and there are two epileptic syndromes, one presenting initially in infancy with gelastic seizures evolving rapidly into a syndrome with multiple seizures, developmental delay and a moderate to severe behaviour disorder.
Abstract: Hypothalamic hamartoma presents with precocious puberty, epilepsy or both. There are two epileptic syndromes, one presenting initially in infancy with gelastic seizures evolving rapidly into a syndrome with multiple seizures, developmental delay and a moderate to severe behaviour disorder. The other presents later with a milder epileptic syndrome, again usually including gelastic seizures, but with normal intellect and behaviour. Magnetic resonance imaging identifies and gives a detailed anatomical picture of these lesions. Direct surgery, using microsurgical techniques and neuronavigation guidance has been used for these lesions. Three surgical approaches have been used, one lateral pterional, another midline frontal through the lamina terminalis and a third is a transcallosal interforniceal approach. In addition a disconnection procedure, usually pterional, aims to disconnect the lesion without the risks of major resection. The transcallosal interforniceal approach is the most successful with 69% of patients seizure-free. There are complications in about 24% of patients, the same as other approaches, but the complications are milder and include fewer neurological deficits than the other routes. Alternate strategies include stereotactic radiosurgery and radiofrequency ablation under stereotactic control.
TL;DR: The intraoperative use of US imaging is a reliable method for determining the size, shape and localization of lesions and can be used as a practicable, cost effective and timesaving real time navigation system.
Abstract: Experience with the use of Intaoperative Ultrasound (US) imaging as real time navigation system in neurosurgery is presented and discussed.
TL;DR: To use the benefits of computer-assisted navigation systems together with immediate availability of intraoperative imaging, a software package called "3D Slicer" is developed that has been used routinely for biopsies and open craniotomies and is stable and reliable.
Abstract: The introduction of MRI into neurosurgery has opened multiple avenues, but also introduced new challenges.
TL;DR: A detailed phantom study which investigates the accuracy in a neuronavigation procedure is presented, and the absence of imaging distortion proved to be crucial for registration accuracy in MR-based procedures.
Abstract: Clinical benefits from neuronavigation are well established. However, the complexity of its technical environment requires a careful evaluation of different types of errors. In this work, a detailed phantom study which investigates the accuracy in a neuronavigation procedure is presented. The dependence on many different imaging parameters, such as field of view, slice thickness and different kind of sequences (sequential and spiral for CT, T1-weighted and T2-weighted for MRI), is quantified. Moreover, data based on CT images are compared to those based on MR images, taking into account MRI distortion. Finally, the contributions to global accuracy coming from image acquisition, registration and navigation itself are discussed. Results demonstrate the importance of imaging accuracy. Procedures based on CT proved to be more accurate than procedures based on MRI. In the former, values from 2 to 2.5 mm are obtained for 95% fractiles of cumulative distribution of Euclidean distances between the intended target and the reached one while, in the latter, the measured values range from 3 to 4 mm. The absence of imaging distortion proved to be crucial for registration accuracy in MR-based procedures.
TL;DR: This study reports the experience with neuronavigation based on CTA in 16 patients with unruptured anterior circulation aneurysms for 1) planning craniotomy; 2) guided approach to theAneurysm; and 3) 3D presentation of the aneurYSm and adjacent arteries in correct orientation.
Abstract: Several reports have demonstrated the use of three-dimensional (3D) computed tomographic angiography (CTA) for preoperative planning in patients with intracranial aneurysms. Until now, there are no reports on the potential role of navigation systems in combination with CTA in aneurysm surgery. In the present study we report our experience with neuronavigation based on CTA in 16 patients with unruptured anterior circulation aneurysms for 1) planning craniotomy; 2) guided approach to the aneurysm; and 3) 3D presentation of the aneurysm and adjacent arteries in correct orientation. The reconstructed CTA images were analyzed preoperatively with regard to diameter of aneurysm neck and dome as well as projection and possible daughter aneurysms, and these parameters were compared with the intraoperative findings. In addition the accuracy of the navigator to locate the aneurysm neck was measured intraoperatively. Navigated approach planning resulted in variable keyhole craniotomies for the 7 middle cerebral artery aneurysms, but did not result in deviation from small standard craniotomies for the internal carotid and anterior communicating artery aneurysms. Precision of the indication of the navigator with regard to the aneurysm neck ranged from < 1 mm to 4 mm. Intraoperative assessment confirmed the CTA data with regard to aneurysm size and projection in all, and definition of daughter aneurysms and adjacent arteries in most cases. The computer assisted approach allowed a smaller, exactly placed craniotomy primarily in MCA aneurysms. 3D presentation of the aneurysms and the adjacent arteries in correct orientation facilitated identification and dissection the aneurysms. Current navigation systems are not precise enough to allow "blind" aneurysm clipping by placing a real clip on the virtual aneurysm neck.
TL;DR: In four patients, whose ages ranged from 29 to 89 years and who harbored undefined lesions invading the CS, neuronavigation was used to perform frameless stereotactic fine-needle biopsy sampling through the foramen ovale, demonstrating a minimally invasive approach in the management of these lesions.
Abstract: Interactive image-guided neuronavigation was used to obtain biopsy specimens of cavernous sinus (CS) tumors via the foramen ovale. In this study the authors demonstrated a minimally invasive approach in the management of these lesions. In four patients, whose ages ranged from 29 to 89 years (mean 61.2 years) and who harbored undefined lesions invading the CS, neuronavigation was used to perform frameless stereotactic fine-needle biopsy sampling through the foramen ovale. The biopsy site was confirmed on postoperative computerized tomography scanning. The frameless technique was accurate in displaying a real-time trajectory of the biopsy needle throughout the procedure. The lesions within the CS were approached precisely and safely. Diagnostic tissue was obtained in all cases and treatment was administered with the aid of stereotactic radiosurgery or fractionated stereotactic radiotherapy. The patients were discharged after an overnight stay with no complications. Neuronavigation is a precise and useful tool for image-guided biopsy sampling of CS tumors via the foramen ovale.
TL;DR: Endoscopic peLLucidotomy of symptomatic cysts of the septum pellucidum produces immediate relief of the mass effect of the cyst and resolution of associated symptoms and frameless neuronavigation is a useful tool in planning and realizing the approach and improving intraoperative orientation.
Abstract: Cavum septi pellucidi and cavum vergae are generally asymptomatic fluid collections between the leaves of the septum pellucidum and are present in approximately 15 % of adult brains. These cavities rarely enlarge and become symptomatic causing significant neurological dysfunction as a result of obstruction of the interventricular foramina, distortion of the vascular structures of the deep venous system or compression of the hypothalamoseptal triangle. The authors present a series of four patients with symptoms related directly to pressure effects from the cyst wall to the neighbouring deep brain structures. There were two females and two males with a mean age of 47.5 years. All four patients underwent endoscopic cyst fenestration with a rigid endoscope. In 2 patients frameless neuronavigation was accomplished with the optical tracking system (Radionics, Burlington, USA). All symptoms related to pressure effect resolved after surgery. Endoscopic pellucidotomy of symptomatic cysts of the septum pellucidum produces immediate relief of the mass effect of the cyst and resolution of associated symptoms. Additionally, frameless neuronavigation is a useful tool in planning and realizing the approach and improving intraoperative orientation.
TL;DR: The clinical application of a neuronavigation system during petrous apex surgery can be regarded as useful and the application of image-guidance in temporal bone surgery causes no additional burden to the patient nor prolongs the operating time.
Abstract: ¶Objectives. To evaluate whether computer-assisted frameless stereotactic navigation in the temporal bone provides sufficient clinical application accuracy and thus a useful tool in temporal bone surgery. Methods. Two patients with petrous apex cholesterol granuloma were operated on by an epidural middle fossa approach using a Stealth/Medtronic™ neuronavigation system. Based on literature data optimal skin fiducial placement and registration methods were used. Intra-operative accuracy was checked using three precise anatomical landmarks. Drilling of the petrous apex bone was guided by neuronavigation. Postoperative Computed Tomography (CT) images were fused with the preoperative CT and planning. Results. The application of image-guidance in temporal bone surgery causes no additional burden to the patient nor prolongs the operating time. The accuracy measured at the anatomical landmarks was under 2,0 mm. This is confirmed by evaluation of bone removal through image fusion of pre- and postoperative CT-scan. Conclusions. The clinical application of a neuronavigation system during petrous apex surgery can be regarded as useful. Using all available data on registration methods it seems possible to obtain intra-operative application accuracies of <2,0 mm. Additional cadaver work is being performed to support these data.
TL;DR: The concordance of results between pre- and intraoperative mapping techniques in patients indicates that preoperative fMRI language mapping may prove useful when planning the resection of intracerebral lesions in language areas.
Abstract: Preoperative functional neuroimaging techniques represent an appealing method to localize language areas in tumor surgery, but their reliability still needs to be confirmed by accurate comparison with more invasive but validated mapping techniques like intraoperative electrical cortical stimulation. Two patients harboring a glioma involving speech areas underwent mapping of language function by preoperative functional magnetic resonance imaging (fMRI), whose results were integrated into the neuronavigation device, and by intraoperative electrical stimulation mapping (ESM). The utilization of neuronavigation allowed us to estimate the degree of spatial correspondence between language areas detected by the two techniques. Language areas identified by functional magnetic resonance imaging on the cerebral cortex exposed during surgery corresponded to those identified by invasive mapping in both patients. It was possible to achieve a gross total tumor removal while respecting language areas in both cases, with no permanent postoperative phasic aggravation. The concordance of results between pre- and intra-operative mapping techniques in our patients indicates that preoperative fMRI language mapping may prove useful when planning the resection of intracerebral lesions in language areas. However, accurate neurofunctional imaging protocols and image analysis are crucial to obtain a preoperative language mapping that is in agreement with ESM findings.
TL;DR: Intraoperative imaging with a mobile CT scanner is a good method for detection of residual tumour and most of the neurosurgical procedures can be well performed with proper neuronavigation planning.
Abstract: Objective: The radicality of tumour removal in patients suffering from glioma is discussed to be an important factor for longer survival times. Therefore intraoperative imaging modalities like magnetic resonance imaging (MRI), computed tomography (CT) and ultrasound (US) are tested in many neurosurgical facilities for clinical use. In our department a mobile CT for intraoperative applications is used for this purpose since 1999. The handling and useful application of the mobile CT scanner as well as results without intraoperative imaging are discussed. Material and Methods: 470 CT scans with the mobile CT were accomplished, including 270 cases of neuronavigation planning, 76 cases of intraoperative scans, 48 cases of postoperative scans, 69 CT scans for stereotactic biopsy planning and control as well as 3 cases of emergency scanning in trauma patients and 4 spine applications. The results of the intraoperative CT scans are compared with those of the postoperative MRI scans. Additionally 87 patients with glioma were evaluated. These patients underwent surgery without intraoperative imaging. Results: In 27 out of 43 patients with glioma residual tumour was detected with intraoperative CT. In 13 cases the surgery was resumed to complete resection, in 14 cases the operation was not continued due to close vicinity to eloquent areas or difficulties in image interpretation. In 44 cases the results of intraoperative CT and postoperative MRI were compared. In 6 cases the MRI demonstrated residual tumour in contrast to the results of the CT scans. In 3 cases the tumour removal could have been more complete (6.8 %). In 87 cases glioma surgery was performed without intraoperative CT. In 6 cases a more complete tumour removal could have been performed (6.9%) according to the results of postoperative MRI. Conclusion: Intraoperative imaging with a mobile CT scanner is a good method for detection of residual tumour. The CT scanner can be integrated in an operative setting without problems. Although intraoperative imaging can be helpful in some selected cases, most of the neurosurgical procedures can be well performed with proper neuronavigation planning.
TL;DR: The integration of fMR imaging and surgical navigation is described, and the potential advantages and pitfalls of its application in clinical practice are discussed.
Abstract: In recent years, surgical navigation systems have become equipped to allow incorporation of data such as functional neuronavigation data. Functional magnetic resonance (fMR) imaging is a noninvasive modality that demonstrates various brain functions. Although still in an experimental stage, fMR imaging is a promising tool for mapping of motor and language functions. One advantage is that it can be implemented in presurgical imaging protocols and is therefore potentially widely available in general neurosurgical practice. In this paper the integration of fMR imaging and surgical navigation is described, and the potential advantages and pitfalls of its application in clinical practice are discussed.
TL;DR: The present operating environment offered useful multimodal information for surgery of brain tumours in critical locations.
Abstract: Background. Development of an image-guided operation theatre offering multimodal information for mini-invasive neurosurgical brain tumour operations.
TL;DR: The initial experience indicates that frameless stereotaxy, in combination with a relocatable head holder and a special targeting device, allows for precise and preplanned advancement of the neuroendoscope, reducing or even eliminating intraoperative registration and endoscope trajectory adjustments, thus substantially reducing OR time.
Abstract: Objective: We present our initial clinical experience with a novel technique of frameless stereotactic neuroendoscopy using a neuronavigation system, a specially designed aiming device (endoscope holder/targeting device) combined with a vacuum-mouthpiece based head holder. Due to the reproducibility of patient immobilization in the fixation system, the endoscope holder can be adjusted in the laboratory in the absence of the patient. Methods: An individual vacuum-mouthpiece was fabricated. The patients were scanned with an external reference frame attached to this mouthpiece and the images were transferred to the neuronavigation system. Determination of the path, mouthpiece-based registration and adjustment of the targeting device were performed the day before surgery in the absence of the patient. In the OR the patient was repositioned and the endoscope was introduced through the preadjusted aiming device to the precalculated depth. Results: The novel technique was successfully used for frameless endoscopic navigation in five patients. Three endoscopic third ventriculostomies in adults, one endoscopic septostomy due to unilateral hydrocephalus in an adult female patient and one endoscopic ventriculo-cysto cisternostomy in a 20-month-old girl with a suprasellar arachnoid cyst, were performed with excellent clinical results and without technical complications. Conclusion: Our initial experience indicates that frameless stereotaxy, in combination with a relocatable head holder and a special targeting device, allows for precise and preplanned advancement of the neuroendoscope, reducing or even eliminating intraoperative registration and endoscope trajectory adjustments, thus substantially reducing OR time. Due to the non-invasive but rigid immobilization method, neuronavigation can also be performed in children under 2 years of age.
TL;DR: The neuronavigation concept proved its value in epilepsy surgery by linking anatomic, pathologic and functional data of the individual patient and Enhanced by the integration of multimodal information, neuronsavigation significantly improved the available treatment options.
Abstract: Objective: For many patients, surgery for intractable epilepsy provides not only freedom or substantial relief from seizures, but also functional improvement and increased quality of life. Precise intraoperative localization of the underlying structural and functional processes is crucial in this regard. The aim of this study was to clinically evaluate whether neuronavigation leads to an improvement in the precision and safety of epilepsy surgery. In this paper, we also attempt to assess the navigation workstation as a platform for the integration of multimodal information (multimodal information guidance).Patients: Out of a series of 223 epilepsy surgery procedures, 140 were performed with the aid of neuronavigation. Patient and surgical data were prospectively collected.Methods: We used the neuronavigation device as a common platform to merge complementary information modalities. Correlation of anatomic and structural details with functional information contributed to the surgical script in non-lesional...
Journal Article•
TL;DR: DTI should be routinely used in neuronavigation surgery of brain tumor involving pyramidal tracts to plan the optimal trajectory and ensure total resection of the lesions during operation, as well as to decrease potential disability after operation and to shorten the length of hospitalization.
Abstract: OBJECTIVE To explore the role of diffusion tensor imaging (DTI) in neuronavigation surgery of brain tumors involving pyramidal tracts. METHODS Forty-nine patients with brain tumors involving pyramidal tracts were randomly divided into trial group (DTI navigation) and control group (traditional navigation). The patients in trial group underwent DTI and T1 weighted 3D navigational magnetic resonance imaging (MRI) studies. The main white matter tracts were constructed by the DTI datasets, and merged to the anatomical structure, which was delineated by the T1-weighted three-dimensional fast spoiled gradient recalled sequence (3D/FSPGR). The relationship between the tumors and adjacent pyramidal tracts were segmented and reconstructed for three-dimensional visualization. RESULTS In 25 patients of trial group and 24 patients of control group, the statistic analysis confirmed well balance of main variations. The tumors were completely resected in 12 patients (50.0%) of control group and in 20 patients (80.0%) of trial group (P < 0.05). Postoperative aggravated contralateral extremities weakness or hemiplegia due to pyramidal tract injury occurring in 75.0% cases of control group whereas only 20.0% patients in trial group (P < 0.01). The mean Karnofsky scale were 69.58 +/- 23.49 and 84.80 +/- 23.49 respectively in control and trial groups (P < 0.05). The excellent outcome ratio (Karnofsky scale = 90 - 100) was 37.5% in control group and 72.0% in trial group respectively (P < 0.05). CONCLUSIONS DTI allows individual estimation of large fiber tracts of brain. Furthermore, to integrate spatial three-dimensional information concerning the white matter tracts into traditional neuronavigation images during surgery, was valuable in presenting topographical character of involving (shift or erosive) pyramidal tracts and relationship with the margins of neighboring tumors. The mapping of large fiber tracts was a safe, efficient, reliable technique. DTI should be routinely used in neuronavigation surgery of brain tumor involving pyramidal tracts to plan the optimal trajectory and ensure total resection of the lesions during operation, as well as to decrease potential disability after operation and to shorten the length of hospitalization.
Journal Article•
TL;DR: Although the method of image-guided surgery was introduced more than a decade ago, new technologies have changed and refined the procedure substantially.
Abstract: Use of surgical navigation systems is becoming an increasingly important part of both planning and performing intracranial and spinal surgery. Numerous clinical reports have described neuronavigation as a useful adjunct to surgery that allows neurosurgery to be less invasive and more effective. Although the method of image-guided surgery was introduced more than a decade ago, new technologies have changed and refined the procedure substantially. This chapter summarizes the recent developments of advanced image-guided surgery. For most operations, microscope navigation has replaced pointer navigation. Using the microscope as the localizing device, the workflow is not interrupted and microsurgical procedure can be continued as usual. New chip technology allows integration of magnetic resonance images, angiography findings, endoscopic view, or other pictures in the eyepiece of the microscope. A new method of patient registration is laser scanning and surface matching. When using high-quality images, this new method can be used without additionally acquired images, may reduce costs, simplify the pre-registration procedure, and increase application accuracy compared to skin-fiducial registration. Moreover, integration of other imaging modalities is becoming an increasingly used feature and provides useful information during surgery.