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Dmitriev AY, Dashyan VG. [Tractography in functional neuronavigation]. Zh Nevrol Psikhiatr Im S S Korsakova 2023; 123:12-18. [PMID: 37490660 DOI: 10.17116/jnevro202312307112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
The review addresses the combined use of tractography and neuronavigation. Fundamentals of diffusion tensor imaging are given, technical aspects of fiber tracking in general and in depicting separate subcortical tracts are described. Main advantages of the method and possible causes of errors are highlighted. Precision assessment of this technology is given by comparing with results of subcortical neurostimulation. Surgical tactics is described depending on distance between the tumor and subcortical pathways.
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Affiliation(s)
- A Yu Dmitriev
- Sklifosovsky Research Institute for Emergency, Moscow, Russia
- Yevdokimov Moscow State University of Medicine and Dentistry, Moscow, Russia
| | - V G Dashyan
- Sklifosovsky Research Institute for Emergency, Moscow, Russia
- Yevdokimov Moscow State University of Medicine and Dentistry, Moscow, Russia
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Koike T, Kin T, Tanaka S, Takeda Y, Uchikawa H, Shiode T, Saito T, Takami H, Takayanagi S, Mukasa A, Oyama H, Saito N. Development of Innovative Neurosurgical Operation Support Method Using Mixed-Reality Computer Graphics. World Neurosurg X 2021; 11:100102. [PMID: 33898969 PMCID: PMC8059082 DOI: 10.1016/j.wnsx.2021.100102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 03/06/2021] [Indexed: 12/22/2022] Open
Abstract
Background In neurosurgery, it is important to inspect the spatial correspondence between the preoperative medical image (virtual space), and the intraoperative findings (real space) to improve the safety of the surgery. Navigation systems and related modalities have been reported as methods for matching this correspondence. However, because of the influence of the brain shift accompanying craniotomy, registration accuracy is reduced. In the present study, to overcome these issues, we developed a spatially accurate registration method of medical fusion 3-dimensional computer graphics and the intraoperative brain surface photograph, and its registration accuracy was measured. Methods The subjects included 16 patients with glioma. Nonrigid registration using the landmarks and thin-plate spline methods was performed for the fusion 3-dimensional computer graphics and the intraoperative brain surface photograph, termed mixed-reality computer graphics. Regarding the registration accuracy measurement, the target registration error was measured by two neurosurgeons, with 10 points for each case at the midpoint of the landmarks. Results The number of target registration error measurement points was 160 in the 16 cases. The target registration error was 0.72 ± 0.04 mm. Aligning the intraoperative brain surface photograph and the fusion 3-dimensional computer graphics required ∼10 minutes on average. The average number of landmarks used for alignment was 24.6. Conclusions Mixed-reality computer graphics enabled highly precise spatial alignment between the real space and virtual space. Mixed-reality computer graphics have the potential to improve the safety of the surgery by allowing complementary observation of brain surface photographs and fusion 3-dimensional computer graphics.
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Key Words
- 2D, 2-Dimensional
- 3D, 3-Dimensional
- 3DCG, 3-Dimensional computer graphics
- AR, Augmented reality
- Brain shift
- CT, Computed tomography
- Computer graphics
- FOV, Field of view
- Glioma
- Landmark
- MRCG, Mixed-reality computer graphics
- MRI, Magnetic resonance imaging
- Mixed-reality
- TE, Echo time
- TR, Repetition time
- Target registration error
- Thin-plate spline
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Affiliation(s)
- Tsukasa Koike
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Taichi Kin
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- To whom correspondence should be addressed: Taichi Kin, M.D.
| | - Shota Tanaka
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yasuhiro Takeda
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroki Uchikawa
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Taketo Shiode
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Toki Saito
- Department of Clinical Information Engineering, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hirokazu Takami
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Shunsaku Takayanagi
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Akitake Mukasa
- Department of Neurosurgery, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Hiroshi Oyama
- Department of Clinical Information Engineering, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Nobuhito Saito
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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Shapey J, Vos SB, Vercauteren T, Bradford R, Saeed SR, Bisdas S, Ourselin S. Clinical Applications for Diffusion MRI and Tractography of Cranial Nerves Within the Posterior Fossa: A Systematic Review. Front Neurosci 2019; 13:23. [PMID: 30809109 PMCID: PMC6380197 DOI: 10.3389/fnins.2019.00023] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 01/11/2019] [Indexed: 12/21/2022] Open
Abstract
Objective: This paper presents a systematic review of diffusion MRI (dMRI) and tractography of cranial nerves within the posterior fossa. We assess the effectiveness of the diffusion imaging methods used and examine their clinical applications. Methods: The Pubmed, Web of Science and EMBASE databases were searched from January 1st 1997 to December 11th 2017 to identify relevant publications. Any study reporting the use of diffusion imaging and/or tractography in patients with confirmed cranial nerve pathology was eligible for selection. Study quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS) tool. Results: We included 41 studies comprising 16 studies of patients with trigeminal neuralgia (TN), 22 studies of patients with a posterior fossa tumor and three studies of patients with other pathologies. Most acquisition protocols used single-shot echo planar imaging (88%) with a single b-value of 1,000 s/mm2 (78%) but there was significant variation in the number of gradient directions, in-plane resolution, and slice thickness between studies. dMRI of the trigeminal nerve generated interpretable data in all cases. Analysis of diffusivity measurements found significantly lower fractional anisotropy (FA) values within the root entry zone of nerves affected by TN and FA values were significantly lower in patients with multiple sclerosis. Diffusivity values within the trigeminal nerve correlate with the effectiveness of surgical treatment and there is some evidence that pre-operative measurements may be predictive of treatment outcome. Fiber tractography was performed in 30 studies (73%). Most studies evaluating fiber tractography involved patients with a vestibular schwannoma (82%) and focused on generating tractography of the facial nerve to assist with surgical planning. Deterministic tractography using diffusion tensor imaging was performed in 93% of cases but the reported success rate and accuracy of generating fiber tracts from the acquired diffusion data varied considerably. Conclusions: dMRI has the potential to inform our understanding of the microstructural changes that occur within the cranial nerves in various pathologies. Cranial nerve tractography is a promising technique but new avenues of using dMRI should be explored to optimize and improve its reliability.
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Affiliation(s)
- Jonathan Shapey
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London, United Kingdom.,Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London, United Kingdom.,School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Sjoerd B Vos
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London, United Kingdom.,Translational Imaging Group-Centre for Medical Image Computing, University College London, London, United Kingdom.,Epilepsy Society MRI Unit, Chalfont St Peter, United Kingdom
| | - Tom Vercauteren
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Robert Bradford
- Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Shakeel R Saeed
- Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London, United Kingdom.,The Ear Institute, University College London, London, United Kingdom.,The Royal National Throat, Nose and Ear Hospital, London, United Kingdom
| | | | - Sebastien Ourselin
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
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Villanueva-Meyer JE, Mabray MC, Cha S. Current Clinical Brain Tumor Imaging. Neurosurgery 2017; 81:397-415. [PMID: 28486641 PMCID: PMC5581219 DOI: 10.1093/neuros/nyx103] [Citation(s) in RCA: 194] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 02/23/2017] [Indexed: 01/12/2023] Open
Abstract
Neuroimaging plays an ever evolving role in the diagnosis, treatment planning, and post-therapy assessment of brain tumors. This review provides an overview of current magnetic resonance imaging (MRI) methods routinely employed in the care of the brain tumor patient. Specifically, we focus on advanced techniques including diffusion, perfusion, spectroscopy, tractography, and functional MRI as they pertain to noninvasive characterization of brain tumors and pretreatment evaluation. The utility of both structural and physiological MRI in the post-therapeutic brain evaluation is also reviewed with special attention to the challenges presented by pseudoprogression and pseudoresponse.
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Affiliation(s)
- Javier E. Villanueva-Meyer
- Department of Radiology and Biomedical Imaging, Neuroradiology Section, University of California San Francisco, San Francisco, California
| | - Marc C. Mabray
- Department of Radiology and Biomedical Imaging, Neuroradiology Section, University of California San Francisco, San Francisco, California
| | - Soonmee Cha
- Department of Radiology and Biomedical Imaging, Neuroradiology Section, University of California San Francisco, San Francisco, California
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Essayed WI, Zhang F, Unadkat P, Cosgrove GR, Golby AJ, O'Donnell LJ. White matter tractography for neurosurgical planning: A topography-based review of the current state of the art. Neuroimage Clin 2017; 15:659-672. [PMID: 28664037 PMCID: PMC5480983 DOI: 10.1016/j.nicl.2017.06.011] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 04/17/2017] [Accepted: 06/08/2017] [Indexed: 12/13/2022]
Abstract
We perform a review of the literature in the field of white matter tractography for neurosurgical planning, focusing on those works where tractography was correlated with clinical information such as patient outcome, clinical functional testing, or electro-cortical stimulation. We organize the review by anatomical location in the brain and by surgical procedure, including both supratentorial and infratentorial pathologies, and excluding spinal cord applications. Where possible, we discuss implications of tractography for clinical care, as well as clinically relevant technical considerations regarding the tractography methods. We find that tractography is a valuable tool in variable situations in modern neurosurgery. Our survey of recent reports demonstrates multiple potentially successful applications of white matter tractography in neurosurgery, with progress towards overcoming clinical challenges of standardization and interpretation.
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Affiliation(s)
- Walid I Essayed
- Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
| | - Fan Zhang
- Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Prashin Unadkat
- Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - G Rees Cosgrove
- Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Alexandra J Golby
- Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Lauren J O'Donnell
- Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
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New Directions in 3D Medical Modeling: 3D-Printing Anatomy and Functions in Neurosurgical Planning. JOURNAL OF HEALTHCARE ENGINEERING 2017; 2017:1439643. [PMID: 29065569 PMCID: PMC5480056 DOI: 10.1155/2017/1439643] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 04/13/2017] [Indexed: 12/03/2022]
Abstract
This paper illustrates the feasibility and utility of combining cranial anatomy and brain function on the same 3D-printed model, as evidenced by a neurosurgical planning case study of a 29-year-old female patient with a low-grade frontal-lobe glioma. We herein report the rapid prototyping methodology utilized in conjunction with surgical navigation to prepare and plan a complex neurosurgery. The method introduced here combines CT and MRI images with DTI tractography, while using various image segmentation protocols to 3D model the skull base, tumor, and five eloquent fiber tracts. This 3D model is rapid-prototyped and coregistered with patient images and a reported surgical navigation system, establishing a clear link between the printed model and surgical navigation. This methodology highlights the potential for advanced neurosurgical preparation, which can begin before the patient enters the operation theatre. Moreover, the work presented here demonstrates the workflow developed at the National University Hospital of Iceland, Landspitali, focusing on the processes of anatomy segmentation, fiber tract extrapolation, MRI/CT registration, and 3D printing. Furthermore, we present a qualitative and quantitative assessment for fiber tract generation in a case study where these processes are applied in the preparation of brain tumor resection surgery.
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Abdolmohammadi J, Shafiee M, Faeghi F, Arefan D, Zali A, Motiei-Langroudi R, Farshidfar Z, Nazarlou AK, Tavakkoli A, Yarham M. Determination of intra-axial brain tumors cellularity through the analysis of T2 Relaxation time of brain tumors before surgery using MATLAB software. Electron Physician 2016; 8:2726-2732. [PMID: 27757181 PMCID: PMC5053452 DOI: 10.19082/2726] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 04/09/2016] [Indexed: 12/04/2022] Open
Abstract
Introduction Timely diagnosis of brain tumors could considerably affect the process of patient treatment. To do so, para-clinical methods, particularly MRI, cannot be ignored. MRI has so far answered significant questions regarding tumor characteristics, as well as helping neurosurgeons. In order to detect the tumor cellularity, neuro-surgeons currently have to sample specimens by biopsy and then send them to the pathology unit. The aim of this study is to determine the tumor cellularity in the brain. Methods In this cross-sectional study, 32 patients (18 males and 14 females from 18–77 y/o) were admitted to the neurosurgery department of Shohada-E Tajrish Hospital in Tehran, Iran from April 2012 to February 2014. In addition to routine pulse sequences, T2W Multi echo pulse sequences were taken and the images were analyzed using the MATLAB software to determine the brain tumor cellularity, compared with the biopsy Results These findings illustrate the need for more T2 relaxation time decreases, the higher classes of tumors will stand out in the designed table. In this study, the results show T2 relaxation time with a 85% diagnostic weight, compared with the biopsy, to determine the brain tumor cellularity (p<0.05). Conclusion Our results indicate that the T2 relaxation time feature is the best method to distinguish and present the degree of intra-axial brain tumors cellularity (85% accuracy compared to biopsy). The use of more data is recommended in order to increase the percent accuracy of this techniques.
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Affiliation(s)
- Jamil Abdolmohammadi
- M.Sc. of Medical Imaging Technology (MRI), Department of Radiology, Faculty of Paramedical Sciences, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | - Mohsen Shafiee
- M.Sc. of Medical Physics, Cellular and Molecular Research Center, Yasuj University of Medical sciences, Yasuj, Iran
| | - Fariborz Faeghi
- Ph.D. in Medical Physics, Radiology Technology Department, School of Allied Medical Sciences, Shahid Beheshti University of Medical Science, Tehran, Iran
| | - Douman Arefan
- Department of Radiation Medicine Engineering, Shahid Beheshti University, Evin, Tehran, Iran
| | - Alireza Zali
- Neurosurgeon, Head of Neurosurgery Department of Shohada-E Tajrish Hospital, Chairman of the Medical Council of Iran, Tehran, Iran
| | - Rouzbeh Motiei-Langroudi
- Department of Neurosurgery, Shohada Tajrish Hospital, Shahid Beheshti University of Medical Science, Tehran, Iran
| | - Zahra Farshidfar
- M.Sc. of Medical Imaging Technology (MRI), Radiology Department of Paramedical School, Shiraz University of Medical Science, Shiraz, Iran
| | - Ali Kiani Nazarlou
- M.Sc. of Medical Imaging Technology, Department of Radiology, Imam Reza Medical Research and Training Hospital, Golgasht Ave., Tabriz, Iran
| | - Ali Tavakkoli
- M.Sc. of Medical Imaging Technology (MRI), Bahonar Medical Research and Training Hospital, Alborz University of Medical Science, Karaj, Iran
| | - Mohammad Yarham
- M.Sc. of Medical Imaging Technology (MRI), Radiology Department of Paramedical School, Shiraz University of Medical Science, Shiraz, Iran
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Coenen VA, Jenkner C, Honey CR, Mädler B. Electrophysiologic Validation of Diffusion Tensor Imaging Tractography during Deep Brain Stimulation Surgery. AJNR Am J Neuroradiol 2016; 37:1470-8. [PMID: 27032969 DOI: 10.3174/ajnr.a4753] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 01/22/2016] [Indexed: 12/29/2022]
Abstract
BACKGROUND AND PURPOSE Diffusion tensor imaging fiber tractography-assisted planning of deep brain stimulation is an emerging technology. We investigated its accuracy by using electrophysiology under clinical conditions. We hypothesized that a level of concordance between electrophysiology and DTI fiber tractography can be reached, comparable with published modeling approaches for deep brain stimulation surgery. MATERIALS AND METHODS Eleven patients underwent subthalamic nucleus deep brain stimulation. DTI scans and high-resolution T1- and T2-weighted MR imaging was performed at 3T. Corticospinal tracts were traced. We studied electrode positions and current amplitudes that elicited corticospinal tract effects during the operation to determine relative corticospinal tract distance. Postoperatively, 3D deep brain stimulation electrode contact locations and stimulation patterns were applied for the same corticospinal tract distance estimation. RESULTS Intraoperative electrophysiologic (n = 40) clinical effects in 11 patients were detected. The mean intraoperative electrophysiologic corticospinal tract distance was 3.0 ± 0.6 mm; the mean image-derived corticospinal tract distance (DTI fiber tractography) was 3.0 ± 1.3 mm. The 95% limits of agreement were ±2.4 mm. Postoperative electrophysiology (n = 44) corticospinal tract activation effects were encountered in 9 patients; 39 were further evaluated. Mean electrophysiologic corticospinal tract distance was 3.7 ± 0.7 mm; for DTI fiber tractography, it was 3.2 ± 1.9 mm. The 95% limits of agreement were ±2.5 mm. CONCLUSIONS DTI fiber tractography depicted the medial corticospinal tract border with proved concordance. Although the overall range of measurements was relatively small and variance was high, we believe that further use of DTI fiber tractography to assist deep brain stimulation procedures is advisable if inherent limitations are respected. These results confirm our previously published electric field simulation studies.
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Affiliation(s)
- V A Coenen
- From the Department of Stereotactic and Functional Neurosurgery (V.A.C., B.M.)
| | - C Jenkner
- the Clinical Trial Unit (C.J.), Freiburg University Medical Center, Freiburg, Germany
| | - C R Honey
- Surgical Center for Movement Disorders/Division of Neurosurgery (C.R.H.)
| | - B Mädler
- From the Department of Stereotactic and Functional Neurosurgery (V.A.C., B.M.) Department of Physics and Astronomy (B.M.), University of British Columbia, Vancouver, British Columbia, Canada Philips Healthcare (B.M.), Hamburg, Germany
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Mert A, Kiesel B, Wöhrer A, Martínez-Moreno M, Minchev G, Furtner J, Knosp E, Wolfsberger S, Widhalm G. Introduction of a standardized multimodality image protocol for navigation-guided surgery of suspected low-grade gliomas. Neurosurg Focus 2015; 38:E4. [PMID: 25552284 DOI: 10.3171/2014.10.focus14597] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Surgery of suspected low-grade gliomas (LGGs) poses a special challenge for neurosurgeons due to their diffusely infiltrative growth and histopathological heterogeneity. Consequently, neuronavigation with multimodality imaging data, such as structural and metabolic data, fiber tracking, and 3D brain visualization, has been proposed to optimize surgery. However, currently no standardized protocol has been established for multimodality imaging data in modern glioma surgery. The aim of this study was therefore to define a specific protocol for multimodality imaging and navigation for suspected LGG. METHODS Fifty-one patients who underwent surgery for a diffusely infiltrating glioma with nonsignificant contrast enhancement on MRI and available multimodality imaging data were included. In the first 40 patients with glioma, the authors retrospectively reviewed the imaging data, including structural MRI (contrast-enhanced T1-weighted, T2-weighted, and FLAIR sequences), metabolic images derived from PET, or MR spectroscopy chemical shift imaging, fiber tracking, and 3D brain surface/vessel visualization, to define standardized image settings and specific indications for each imaging modality. The feasibility and surgical relevance of this new protocol was subsequently prospectively investigated during surgery with the assistance of an advanced electromagnetic navigation system in the remaining 11 patients. Furthermore, specific surgical outcome parameters, including the extent of resection, histological analysis of the metabolic hotspot, presence of a new postoperative neurological deficit, and intraoperative accuracy of 3D brain visualization models, were assessed in each of these patients. RESULTS After reviewing these first 40 cases of glioma, the authors defined a specific protocol with standardized image settings and specific indications that allows for optimal and simultaneous visualization of structural and metabolic data, fiber tracking, and 3D brain visualization. This new protocol was feasible and was estimated to be surgically relevant during navigation-guided surgery in all 11 patients. According to the authors' predefined surgical outcome parameters, they observed a complete resection in all resectable gliomas (n = 5) by using contour visualization with T2-weighted or FLAIR images. Additionally, tumor tissue derived from the metabolic hotspot showed the presence of malignant tissue in all WHO Grade III or IV gliomas (n = 5). Moreover, no permanent postoperative neurological deficits occurred in any of these patients, and fiber tracking and/or intraoperative monitoring were applied during surgery in the vast majority of cases (n = 10). Furthermore, the authors found a significant intraoperative topographical correlation of 3D brain surface and vessel models with gyral anatomy and superficial vessels. Finally, real-time navigation with multimodality imaging data using the advanced electromagnetic navigation system was found to be useful for precise guidance to surgical targets, such as the tumor margin or the metabolic hotspot. CONCLUSIONS In this study, the authors defined a specific protocol for multimodality imaging data in suspected LGGs, and they propose the application of this new protocol for advanced navigation-guided procedures optimally in conjunction with continuous electromagnetic instrument tracking to optimize glioma surgery.
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Pujol S, Wells W, Pierpaoli C, Brun C, Gee J, Cheng G, Vemuri B, Commowick O, Prima S, Stamm A, Goubran M, Khan A, Peters T, Neher P, Maier-Hein KH, Shi Y, Tristan-Vega A, Veni G, Whitaker R, Styner M, Westin CF, Gouttard S, Norton I, Chauvin L, Mamata H, Gerig G, Nabavi A, Golby A, Kikinis R. The DTI Challenge: Toward Standardized Evaluation of Diffusion Tensor Imaging Tractography for Neurosurgery. J Neuroimaging 2015; 25:875-82. [PMID: 26259925 DOI: 10.1111/jon.12283] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 06/23/2015] [Accepted: 06/24/2015] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE Diffusion tensor imaging (DTI) tractography reconstruction of white matter pathways can help guide brain tumor resection. However, DTI tracts are complex mathematical objects and the validity of tractography-derived information in clinical settings has yet to be fully established. To address this issue, we initiated the DTI Challenge, an international working group of clinicians and scientists whose goal was to provide standardized evaluation of tractography methods for neurosurgery. The purpose of this empirical study was to evaluate different tractography techniques in the first DTI Challenge workshop. METHODS Eight international teams from leading institutions reconstructed the pyramidal tract in four neurosurgical cases presenting with a glioma near the motor cortex. Tractography methods included deterministic, probabilistic, filtered, and global approaches. Standardized evaluation of the tracts consisted in the qualitative review of the pyramidal pathways by a panel of neurosurgeons and DTI experts and the quantitative evaluation of the degree of agreement among methods. RESULTS The evaluation of tractography reconstructions showed a great interalgorithm variability. Although most methods found projections of the pyramidal tract from the medial portion of the motor strip, only a few algorithms could trace the lateral projections from the hand, face, and tongue area. In addition, the structure of disagreement among methods was similar across hemispheres despite the anatomical distortions caused by pathological tissues. CONCLUSIONS The DTI Challenge provides a benchmark for the standardized evaluation of tractography methods on neurosurgical data. This study suggests that there are still limitations to the clinical use of tractography for neurosurgical decision making.
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Affiliation(s)
- Sonia Pujol
- Surgical Planning Laboratory, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - William Wells
- Surgical Planning Laboratory, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Carlo Pierpaoli
- Program on Pediatric Imaging and Tissue Sciences, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda
| | - Caroline Brun
- Penn Image Computing and Science Laboratory, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - James Gee
- Penn Image Computing and Science Laboratory, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Guang Cheng
- Department of Computer and Information Science and Engineering, University of Florida, Gainesville
| | - Baba Vemuri
- Department of Computer and Information Science and Engineering, University of Florida, Gainesville
| | - Olivier Commowick
- University of Rennes I, VISAGES INSERM - U746 CNRS UMR6074 - INRIA, Rennes, France
| | - Sylvain Prima
- University of Rennes I, VISAGES INSERM - U746 CNRS UMR6074 - INRIA, Rennes, France
| | - Aymeric Stamm
- University of Rennes I, VISAGES INSERM - U746 CNRS UMR6074 - INRIA, Rennes, France
| | - Maged Goubran
- Imaging Laboratories, Robarts Research Institute, Western University, London, ON, Canada
| | - Ali Khan
- Imaging Laboratories, Robarts Research Institute, Western University, London, ON, Canada
| | - Terry Peters
- Imaging Laboratories, Robarts Research Institute, Western University, London, ON, Canada
| | - Peter Neher
- Junior Group Medical Image Computing, Division of Medical and Biological Informatics, German Cancer Research Center, Heidelberg, Germany
| | - Klaus H Maier-Hein
- Junior Group Medical Image Computing, Division of Medical and Biological Informatics, German Cancer Research Center, Heidelberg, Germany
| | - Yundi Shi
- Department of Psychiatry and Computer Science, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Antonio Tristan-Vega
- Department of Mechanical Engineering, Universidad de Valladolid, Valladolid, Spain
| | - Gopalkrishna Veni
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT
| | - Ross Whitaker
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT
| | - Martin Styner
- Department of Psychiatry and Computer Science, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Carl-Fredrik Westin
- Laboratory of Mathematics in Imaging, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Sylvain Gouttard
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT
| | - Isaiah Norton
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Laurent Chauvin
- Surgical Navigation and Robotics Laboratory, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Hatsuho Mamata
- Surgical Planning Laboratory, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Guido Gerig
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT
| | - Arya Nabavi
- International Neuroscience Institute (INI), Hannover, Germany
| | - Alexandra Golby
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Ron Kikinis
- Surgical Planning Laboratory, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
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Cho JM, Kim EH, Kim J, Lee SK, Kim SH, Lee KS, Chang JH. Clinical use of diffusion tensor image-merged functional neuronavigation for brain tumor surgeries: review of preoperative, intraoperative, and postoperative data for 123 cases. Yonsei Med J 2014; 55:1303-9. [PMID: 25048489 PMCID: PMC4108816 DOI: 10.3349/ymj.2014.55.5.1303] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
PURPOSE To achieve maximal safe resection during brain tumor surgery, functional image-merged neuronavigation is widely used. We retrospectively reviewed our cases in which diffusion tensor image (DTI)-merged functional neuronavigation was performed during surgery. MATERIALS AND METHODS Between November 2008 and May 2010, 123 patients underwent surgery utilizing DTI-merged neuronavigation. Anatomical magnetic resonance images (MRI) were obtained preoperatively and fused with DTI of major white matter tracts, such as the corticospinal tract, optic radiation, or arcuate fasciculus. We used this fused image for functional neuronavigation during brain tumor surgery of eloquent areas. We checked the DTI images together with postoperative MRI images and evaluated the integrity of white matter tracts. RESULTS A single white matter tract was inspected in 78 patients, and two or more white matter tracts were checked in 45 patients. Among the 123 patients, a grossly total resection was achieved in 90 patients (73.2%), subtotal resection in 29 patients (23.6%), and partial resection in 4 patients (3.3%). Postoperative neurologic outcomes, compared with preoperative function, included the following: 100 patients (81.3%) displayed improvement of neurologic symptoms or no change, 7 patients (5.7%) experienced postoperative permanent neurologic deterioration (additional or aggravated neurologic symptoms), and 16 patients (13.0%) demonstrated transient worsening. CONCLUSION DTI-merged functional neuronavigation could be a useful tool in brain tumor surgery for maximal safe resection. However, there are still limitations, including white matter tract shift, during surgery and in DTI itself. Further studies should be conducted to overcome these limitations.
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Affiliation(s)
- Jin Mo Cho
- Department of Neurosurgery, International St. Mary's Hospital, Incheon, Korea. ; Department of Medicine, Graduate School, Yonsei University, Seoul, Korea
| | - Eui Hyun Kim
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea. ; Brain Tumor Center, Yonsei University College of Medicine, Seoul, Korea. ; Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Jinna Kim
- Department of Radiology, Yonsei University College of Medicine, Seoul, Korea. ; Brain Tumor Center, Yonsei University College of Medicine, Seoul, Korea
| | - Seung Koo Lee
- Department of Radiology, Yonsei University College of Medicine, Seoul, Korea. ; Brain Tumor Center, Yonsei University College of Medicine, Seoul, Korea
| | - Sun Ho Kim
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea. ; Brain Tumor Center, Yonsei University College of Medicine, Seoul, Korea. ; Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Kyu Sung Lee
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea. ; Brain Tumor Center, Yonsei University College of Medicine, Seoul, Korea. ; Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Jong Hee Chang
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea. ; Brain Tumor Center, Yonsei University College of Medicine, Seoul, Korea. ; Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea
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12
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D'Amico RS, Kennedy BC, Bruce JN. Neurosurgical oncology: advances in operative technologies and adjuncts. J Neurooncol 2014; 119:451-63. [PMID: 24969924 DOI: 10.1007/s11060-014-1493-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 05/22/2014] [Indexed: 12/31/2022]
Abstract
Modern glioma surgery has evolved around the central tenet of safely maximizing resection. Recent surgical adjuncts have focused on increasing the maximum extent of resection while minimizing risk to functional brain. Technologies such as cortical and subcortical stimulation mapping, intraoperative magnetic resonance imaging, functional neuronavigation, navigable intraoperative ultrasound, neuroendoscopy, and fluorescence-guided resection have been developed to augment the identification of tumor while preserving brain anatomy and function. However, whether these technologies offer additional long-term benefits to glioma patients remains to be determined. Here we review advances over the past decade in operative technologies that have offered the most promising benefits for glioblastoma patients.
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Affiliation(s)
- Randy S D'Amico
- Department of Neurological Surgery, Neurological Institute, Columbia University Medical Center, 4th Floor, 710 West 168th Street, New York, NY, 10032, USA,
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13
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Mandelli ML, Berger MS, Bucci M, Berman JI, Amirbekian B, Henry RG. Quantifying accuracy and precision of diffusion MR tractography of the corticospinal tract in brain tumors. J Neurosurg 2014; 121:349-58. [PMID: 24905560 DOI: 10.3171/2014.4.jns131160] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT The aim of this paper was to validate the diffusion tensor imaging (DTI) model for delineation of the corticospinal tract using cortical and subcortical white matter electrical stimulation for the location of functional motor pathways. METHODS The authors compare probabilistic versus deterministic DTI fiber tracking by reconstructing the pyramidal fiber tracts on preoperatively acquired DTI in patients with brain tumors. They determined the accuracy and precision of these 2 methods using subcortical stimulation points and the sensitivity using cortical stimulation points. The authors further explored the reliability of these methods by estimation of the potential that the found connections were due to a random chance using a novel neighborhood permutation method. RESULTS The probabilistic tracking method delineated tracts that were significantly closer to the stimulation points and was more sensitive than deterministic DTI fiber tracking to define the tracts directed to the motor sites. However, both techniques demonstrated poor sensitivity to finding lateral motor regions. CONCLUSIONS This study highlights the importance of the validation and quantification of preoperative fiber tracking with the aid of electrophysiological data during the surgery. The poor sensitivity of DTI to delineate lateral motor pathways reported herein suggests that DTI fiber tracking must be used with caution and only as adjunctive data to established methods for motor mapping.
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14
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Abdullah KG, Lubelski D, Nucifora PGP, Brem S. Use of diffusion tensor imaging in glioma resection. Neurosurg Focus 2014; 34:E1. [PMID: 23544405 DOI: 10.3171/2013.1.focus12412] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Diffusion tensor imaging (DTI) is increasingly used in the resection of both high- and low-grade gliomas. Whereas conventional MRI techniques provide only anatomical information, DTI offers data on CNS connectivity by enabling visualization of important white matter tracts in the brain. Importantly, DTI allows neurosurgeons to better guide their surgical approach and resection. Here, the authors review basic scientific principles of DTI, include a primer on the technology and image acquisition, and outline the modality's evolution as a frequently used tool for glioma resection. Current literature supporting its use is summarized, highlighting important clinical studies on the application of DTI in preoperative planning for glioma resection, preoperative diagnosis, and postoperative outcomes. The authors conclude with a review of future directions for this technology.
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Affiliation(s)
- Kalil G Abdullah
- Department of Neurosurgery, Section of Neuroradiology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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15
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Vos SB, Viergever MA, Leemans A. Multi-fiber tractography visualizations for diffusion MRI data. PLoS One 2013; 8:e81453. [PMID: 24282597 PMCID: PMC3839966 DOI: 10.1371/journal.pone.0081453] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 10/13/2013] [Indexed: 12/13/2022] Open
Abstract
In recent years, several new diffusion MRI approaches have been proposed to explore microstructural properties of the white matter, such as Q-ball imaging and spherical deconvolution-based techniques to estimate the orientation distribution function. These methods can describe the estimated diffusion profile with a higher accuracy than the more conventional second-rank diffusion tensor imaging technique. Despite many important advances, there are still inconsistent findings between different models that investigate the "crossing fibers" issue. Due to the high information content and the complex nature of the data, it becomes virtually impossible to interpret and compare results in a consistent manner. In this work, we present novel fiber tractography visualization approaches that provide a more complete picture of the microstructural architecture of fiber pathways: multi-fiber hyperstreamlines and streamribbons. By visualizing, for instance, the estimated fiber orientation distribution along the reconstructed tract in a continuous way, information of the local fiber architecture is combined with the global anatomical information derived from tractography. Facilitating the interpretation of diffusion MRI data, this approach can be useful for comparing different diffusion reconstruction techniques and may improve our understanding of the intricate white matter network.
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Affiliation(s)
- Sjoerd B. Vos
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Max A. Viergever
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Alexander Leemans
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
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16
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Talacchi A, Santini B, Casagrande F, Alessandrini F, Zoccatelli G, Squintani GM. Awake surgery between art and science. Part I: clinical and operative settings. FUNCTIONAL NEUROLOGY 2013; 28:205-21. [PMID: 24139657 DOI: 10.11138/fneur/2013.28.3.205] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Awake surgery requires coordinated teamwork and communication between the surgeon and the anesthesiologist, as he monitors the patient, the neuroradiologist as he interprets the images for intraoperative confirmation, and the neuropsychologist and neurophysiologist as they evaluate in real-time the patient's responses to commands and questions. To improve comparison across published studies on clinical assessment and operative settings in awake surgery, we reviewed the literature, focusing on methodological differences and aims. In complex, interdisciplinary medical care, such differences can affect the outcome and the cost-benefit ratio of the treatment. Standardization of intraoperative mapping and related controversies will be discussed in Part II.
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17
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Tarapore PE, Martino J, Guggisberg AG, Owen J, Honma SM, Findlay A, Berger MS, Kirsch HE, Nagarajan SS. Magnetoencephalographic imaging of resting-state functional connectivity predicts postsurgical neurological outcome in brain gliomas. Neurosurgery 2013; 71:1012-22. [PMID: 22895403 DOI: 10.1227/neu.0b013e31826d2b78] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The removal of brain tumors in perieloquent or eloquent cortex risks causing new neurological deficits in patients. The assessment of the functionality of perilesional tissue is essential to avoid postoperative neurological morbidity. OBJECTIVE To evaluate preoperative magnetoencephalography-based functional connectivity as a predictor of short- and medium-term neurological outcome after removal of gliomas in perieloquent and eloquent areas. METHODS Resting-state whole-brain magnetoencephalography recordings were obtained from 79 consecutive subjects with focal brain gliomas near or within motor, sensory, or language areas. Neural activity was estimated using adaptive spatial filtering. The mean imaginary coherence between voxels in and around brain tumors was compared with contralesional voxels and used as an index of their functional connectivity with the rest of the brain. The connectivity values of the tissue resected during surgery were correlated with the early (1 week postoperatively) and medium-term (6 months postoperatively) neurological morbidity. RESULTS Patients undergoing resection of tumors with decreased functional connectivity had a 29% rate of a new neurological deficit 1 week after surgery and a 0% rate at 6-month follow-up. Patients undergoing resection of tumors with increased functional connectivity had a 60% rate of a new deficit at 1 week and a 25% rate at 6 months. CONCLUSION Magnetoencephalography connectivity analysis gives a valuable preoperative evaluation of the functionality of the tissue surrounding tumors in perieloquent and eloquent areas. These data may be used to optimize preoperative patient counseling and surgical strategy.
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Affiliation(s)
- Phiroz E Tarapore
- Department of Neurological Surgery, University of California-San Francisco, San Francisco, California 94143-0628, USA
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18
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Qiu MG, Zhang JN, Zhang Y, Li QY, Xie B, Wang J. Diffusion tensor imaging-based research on human white matter anatomy. ScientificWorldJournal 2012; 2012:530432. [PMID: 23226983 PMCID: PMC3512272 DOI: 10.1100/2012/530432] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 10/14/2012] [Indexed: 11/17/2022] Open
Abstract
The aim of this study is to investigate the white matter by the diffusion tensor imaging and the Chinese visible human dataset and to provide the 3D anatomical data of the corticospinal tract for the neurosurgical planning by studying the probabilistic maps and the reproducibility of the corticospinal tract. Diffusion tensor images and high-resolution T1-weighted images of 15 healthy volunteers were acquired; the DTI data were processed using DtiStudio and FSL software. The FA and color FA maps were compared with the sectional images of the Chinese visible human dataset. The probability maps of the corticospinal tract were generated as a quantitative measure of reproducibility for each voxel of the stereotaxic space. The fibers displayed by the diffusion tensor imaging were well consistent with the sectional images of the Chinese visible human dataset and the existing anatomical knowledge. The three-dimensional architecture of the white matter fibers could be clearly visualized on the diffusion tensor tractography. The diffusion tensor tractography can establish the 3D probability maps of the corticospinal tract, in which the degree of intersubject reproducibility of the corticospinal tract is consistent with the previous architectonic report. DTI is a reliable method of studying the fiber connectivity in human brain, but it is difficult to identify the tiny fibers. The probability maps are useful for evaluating and identifying the corticospinal tract in the DTI, providing anatomical information for the preoperative planning and improving the accuracy of surgical risk assessments preoperatively.
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Affiliation(s)
- Ming-guo Qiu
- Department of Medical Informatics and Medical Image, College of Biomedical Engineering and Medical Imaging, Third Military Medical University, Chongqing 400038, China.
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19
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Elhawary H, Liu H, Patel P, Norton I, Rigolo L, Papademetris X, Hata N, Golby AJ. Intraoperative real-time querying of white matter tracts during frameless stereotactic neuronavigation. Neurosurgery 2011; 68:506-16; discussion 516. [PMID: 21135719 PMCID: PMC3121103 DOI: 10.1227/neu.0b013e3182036282] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Brain surgery faces important challenges when trying to achieve maximum tumor resection while avoiding postoperative neurological deficits. OBJECTIVE For surgeons to have optimal intraoperative information concerning white matter (WM) anatomy, we developed a platform that allows the intraoperative real-time querying of tractography data sets during frameless stereotactic neuronavigation. METHODS Structural magnetic resonance imaging, functional magnetic resonance imaging, and diffusion tensor imaging were performed on 5 patients before they underwent lesion resection using neuronavigation. During the procedure, the tracked surgical tool tip position was transferred from the navigation system to the 3-dimensional Slicer software package, which used this position to seed the WM tracts around the tool tip location, rendering a geometric visualization of these tracts on the preoperative images previously loaded onto the navigation system. The clinical feasibility of this approach was evaluated in 5 cases of lesion resection. In addition, system performance was evaluated by measuring the latency between surgical tool tracking and visualization of the seeded WM tracts. RESULTS Lesion resection was performed successfully in all 5 patients. The seeded WM tracts close to the lesion and other critical structures, as defined by the functional and structural images, were interactively visualized during the intervention to determine their spatial relationships relative to the lesion and critical cortical areas. Latency between tracking and visualization of tracts was less than a second for a fiducial radius size of 4 to 5 mm. CONCLUSION Interactive tractography can provide an intuitive way to inspect critical WM tracts in the vicinity of the surgical region, allowing the surgeon to have increased intraoperative WM information to execute the planned surgical resection.
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Affiliation(s)
- Haytham Elhawary
- Surgical Planning Laboratory, Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA
| | - Haiying Liu
- Surgical Planning Laboratory, Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA
| | - Pratik Patel
- BrainLAB AG, Feldkirchen, Germany. http://www.brainlab.com
| | - Isaiah Norton
- Golby Laboratory, Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA
| | - Laura Rigolo
- Golby Laboratory, Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA
| | - Xenophon Papademetris
- Department of Diagnostic Radiology, Yale University of Medicine, and Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Nobuhiko Hata
- Surgical Planning Laboratory, Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA
| | - Alexandra J. Golby
- Surgical Planning Laboratory, Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA
- Golby Laboratory, Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA
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Chung HW, Chou MC, Chen CY. Principles and limitations of computational algorithms in clinical diffusion tensor MR tractography. AJNR Am J Neuroradiol 2010; 32:3-13. [PMID: 20299436 DOI: 10.3174/ajnr.a2041] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
There have been numerous reports documenting the graphic reconstruction of 3D white matter architecture in the human brain by means of diffusion tensor MR tractography. Different from other reviews addressing the physics and clinical applications of DTI, this article reviews the computational principles of tractography algorithms appearing in the literature. The simplest voxel-based method and 2 widely used subvoxel approaches are illustrated first, together with brief notes on parameter selection and the restrictions arising from the distinct attributes of tract estimations. Subsequently, some advanced techniques attempting to offer improvement in various aspects are briefly introduced, including the increasingly popular research tracking tool using HARDI. The article explains the inherent technical limitations in most of the algorithms reported to date and concludes by providing a reference guideline for formulating routine applications of this important tool to clinical neuroradiology in an objective and reproducible manner.
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Affiliation(s)
- H-W Chung
- Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan, Republic of China
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21
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Bello L, Castellano A, Fava E, Casaceli G, Riva M, Scotti G, Gaini SM, Falini A. Intraoperative use of diffusion tensor imaging fiber tractography and subcortical mapping for resection of gliomas: technical considerations. Neurosurg Focus 2010; 28:E6. [PMID: 20121441 DOI: 10.3171/2009.12.focus09240] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Resection of lesions involving motor or language areas or pathways requires the intraoperative identification of functional cortical and subcortical sites for effectively and safe guidance. Diffusion tensor (DT) imaging and fiber tractography are MR imaging techniques based on the concept of anisotropic water diffusion in myelinated fibers, which enable 3D reconstruction and visualization of white matter tracts and provide information about the relationship of these tracts to the tumor mass. The authors routinely used DT imaging fiber tractography to reconstruct various tracts involved in the motor and/or language system in a large series of patients with lesions involving the motor and/or language areas or pathways. The DT imaging fiber tractography data were loaded into the neuronavigational system and combined intraoperatively with those obtained from direct electrical stimulation applied at the subcortical level. In this paper the authors report the results of their experience, describing the findings for each tract and discussing technical aspects of the combined use as well as the pitfalls.
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Affiliation(s)
- Lorenzo Bello
- Division of Neurosurgery, Department of Neurological Sciences, Università degli Studi di Milano, 20122 Milan, Italy.
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22
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Yamada K, Sakai K, Akazawa K, Yuen S, Nishimura T. MR tractography: a review of its clinical applications. Magn Reson Med Sci 2010; 8:165-74. [PMID: 20035125 DOI: 10.2463/mrms.8.165] [Citation(s) in RCA: 213] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Magnetic resonance tractography based on diffusion-tensor imaging was first introduced to the medical imaging community a decade ago. It has been successfully applied to a number of neurological conditions and most commonly used for preoperative planning for brain tumors and vascular malformations. Areas of active research include stroke, and dementia, where it provides valuable information not available through other imaging techniques. This technique was first introduced using the deterministic streamline algorithm and has evolved to use more sophisticated probabilistic approaches. We will review the past, present, and future of tractography, focusing primarily on its clinical applications.
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Affiliation(s)
- Kei Yamada
- Department of Radiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
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MIKUNI N, MIYAMOTO S. Surgical Treatment for Glioma: Extent of Resection Applying Functional Neurosurgery. Neurol Med Chir (Tokyo) 2010; 50:720-6. [DOI: 10.2176/nmc.50.720] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Nobuhiro MIKUNI
- Department of Neurosurgery, Kyoto University Graduate School of Medicine
| | - Susumu MIYAMOTO
- Department of Neurosurgery, Kyoto University Graduate School of Medicine
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Duffau H, Peggy Gatignol ST, Mandonnet E, Capelle L, Taillandier L. Intraoperative subcortical stimulation mapping of language pathways in a consecutive series of 115 patients with Grade II glioma in the left dominant hemisphere. J Neurosurg 2008; 109:461-71. [PMID: 18759577 DOI: 10.3171/jns/2008/109/9/0461] [Citation(s) in RCA: 343] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECT Despite better knowledge of cortical language organization, its subcortical anatomofunctional connectivity remains poorly understood. The authors used intraoperative subcortical stimulation in awake patients undergoing operation for a glioma in the left dominant hemisphere to map the language pathways and to determine the contribution of such a method to surgical results. METHODS One hundred fifteen patients harboring a World Health Organization Grade II glioma within language areas underwent operation after induction of local anesthesia, using direct electrical stimulation to perform online cortical and subcortical language mapping throughout the resection. RESULTS After detection of cortical language sites, the authors identified 1 or several of the following subcortical language pathways in all patients: 1) arcuate fasciculus, eliciting phonemic paraphasia when stimulated; 2) inferior frontooccipital fasciculus, generating semantic paraphasia when stimulated; 3) subcallosal fasciculus, inducing transcortical motor aphasia during stimulation; 4) frontoparietal phonological loop, eliciting speech apraxia during stimulation; and 5) fibers coming from the ventral premotor cortex, inducing anarthria when stimulated. These structures were preserved, representing the limits of the resection. Despite a transient immediate postoperative worsening, all but 2 patients (98%) returned to baseline or better. On control MR imaging, 83% of resections were total or subtotal. CONCLUSIONS These results represent the largest experience with human subcortical language mapping ever reported. The use of intraoperative cortical and subcortical stimulation gives a unique opportunity to perform an accurate and reliable real-time anatomofunctional study of language connectivity. Such knowledge of the individual organization of language networks enables practitioners to optimize the benefit-to-risk ratio of surgery for Grade II glioma within the left dominant hemisphere.
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Affiliation(s)
- Hugues Duffau
- Department of Neurosurgery, Hôpital Gui de Chauliac, Montpellier, Paris, France.
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Nimsky C, Ganslandt O, Weigel D, von Keller B, Stadlbauer A, Akutsu H, Hammen T, Buchfelder M. Intraoperative Tractography and Neuronavigation of the Pyramidal Tract( Functional Neurophysiological Monitoring for Neurosurgery). ACTA ACUST UNITED AC 2008. [DOI: 10.7887/jcns.17.21] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Ch Nimsky
- Department of Neurosurgery, University Erlangen-Nuremberg
| | - O Ganslandt
- Department of Neurosurgery, University Erlangen-Nuremberg
| | - D Weigel
- Department of Neurosurgery, University Erlangen-Nuremberg
| | - B von Keller
- Department of Neurosurgery, University Erlangen-Nuremberg
| | - A Stadlbauer
- Department of Neurosurgery, University Erlangen-Nuremberg
| | - H Akutsu
- Department of Neurosurgery, University Erlangen-Nuremberg
| | - T Hammen
- Department of Neurology, University Erlangen-Nuremberg
| | - M Buchfelder
- Department of Neurosurgery, University Erlangen-Nuremberg
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Mikuni N, Okada T, Enatsu R, Miki Y, Hanakawa T, Urayama SI, Kikuta K, Takahashi JA, Nozaki K, Fukuyama H, Hashimoto N. Clinical impact of integrated functional neuronavigation and subcortical electrical stimulation to preserve motor function during resection of brain tumors. J Neurosurg 2007; 106:593-8. [PMID: 17432708 DOI: 10.3171/jns.2007.106.4.593] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
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 I 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.
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Affiliation(s)
- Nobuhiro Mikuni
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan.
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27
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Okada T, Mikuni N, Miki Y, Kikuta KI, Urayama SI, Hanakawa T, Fushimi Y, Yamamoto A, Kanagaki M, Fukuyama H, Hashimoto N, Togashi K. Corticospinal Tract Localization: Integration of Diffusion-Tensor Tractography at 3-T MR Imaging with Intraoperative White Matter Stimulation Mapping—Preliminary Results. Radiology 2006; 240:849-57. [PMID: 16857980 DOI: 10.1148/radiol.2403050916] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Institutional review board approval and written informed consent were obtained. The purpose of this study was to prospectively validate usefulness of diffusion-tensor (DT) fiber tractography of the corticospinal tract at 3-T magnetic resonance imaging, in combination with the subcortical motor-evoked potential (MEP) technique, as a tool for tractography-guided neurosurgery. DT imaging and corticospinal tractography were performed at 3 T in eight patients (four men, four women; mean age, 41 years; age range, 23-58 years) with intracranial space-occupying lesions. Tractography data were transferred to a neuronavigation system, and tractography-guided neurosurgery was performed. During lesion resection, subcortical MEPs were recorded. Positive MEP response was observed in four patients. No patients developed new motor weakness postoperatively. Complementary use of tractography and MEP may be useful for intraoperative depiction of corticospinal tracts.
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Affiliation(s)
- Tsutomu Okada
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
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Hlatky R, Jackson EF, Weinberg JS, McCutcheon IE. intraoperative neuronavigation using diffusion tensor MR tractography for the resection of a deep tumor adjacent to the corticospinal tract. Stereotact Funct Neurosurg 2006; 83:228-32. [PMID: 16534255 DOI: 10.1159/000091954] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE AND IMPORTANCE Delineation of cerebral white matter tracts using MR tractography adds essential information for planning intracranial surgery. Integrating tractography with intraoperative neuronavigation may reduce the likelihood of new neurological deficits after surgery done to remove tumors adjacent to the projection fibers of eloquent cortex. We report the utility of such integration for the resection of deep (paraventricular) tumors. CLINICAL PRESENTATION A 67-year-old male with malignant melanoma underwent stereotactic radiosurgery for a single metastasis within the paraventricular white matter of the right frontal lobe near the corticospinal tract. The lesion doubled in size within 12 months of radiotherapy. Surgical extirpation was performed aided by intraoperative neuronavigation. TECHNIQUE MR images of the brain including MR tractography and post-contrast T1-weighted sequences were acquired and imported into a neuronavigational workstation. Asymmetric fusion of contrast-enhanced images and tractography was employed to assist in preservation of the integrity of critical white matter tracts during the surgical procedure. CONCLUSION Inclusion of tractography in standard imaging protocols for neuronavigational systems may increase the safety of neurosurgical intervention near white matter tracts, including deep areas adjacent to the ventricles.
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Affiliation(s)
- Roman Hlatky
- Department of Neurosurgery, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
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Nimsky C, Ganslandt O, von Keller B, Fahlbusch R. Intraoperative high-field MRI: anatomical and functional imaging. ACTA NEUROCHIRURGICA. SUPPLEMENT 2006; 98:87-95. [PMID: 17009705 DOI: 10.1007/978-3-211-33303-7_12] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Intraoperative high-field magnetic resonance (MR) imaging with integrated microscope-based navigation is at present one of the most sophisticated technical methods providing a reliable immediate intraoperative quality control. It enables intraoperative imaging at high quality that is up to the standard of up to date pre- and postoperative neuroradiological routine diagnostics. The major indications are pituitary tumor surgery and glioma surgery. In pituitary tumor surgery intraoperative MRI helps to localize hidden tumor remnants that would be otherwise overlooked. The same is true for glioma surgery, where the optimal extent of resection by simultaneous preservation of functional integrity can be achieved. This is possible since high-field MR imaging offers various modalities beyond standard anatomical imaging, such as MR spectroscopy, diffusion tensor imaging, and functional MR imaging which may also be applied intraoperatively, providing not only data on the extent of resection and localization of tumor remnants but also on metabolic changes, tumor invasion, and localization of functional eloquent cortical and deep-seated brain areas.
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Affiliation(s)
- C Nimsky
- Department of Neurosurgery, University Erlangen-Nuremberg, Erlangen, Germany.
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Coenen VA, Huber KK, Krings T, Weidemann J, Gilsbach JM, Rohde V. Diffusion-weighted imaging-guided resection of intracerebral lesions involving the optic radiation. Neurosurg Rev 2005; 28:188-95. [PMID: 15747136 DOI: 10.1007/s10143-005-0385-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Revised: 01/08/2005] [Accepted: 01/27/2005] [Indexed: 11/25/2022]
Abstract
In this paper we report our experience with diffusion-weighted imaging (DWI) for optic radiation (OR) visualization during resection of tumors. We hypothesize that intraoperative OR visualization helps to maintain patients' visual fields. DWI studies were performed together with T1-weighted postcontrast magnetic resonance imaging (MRI) in four patients with lesions in or adjacent to the OR (glioblastoma, oligo-astrocytoma, cavernoma, and metastasis; n = 1 each). The OR was identified from one of six DWI data acquisitions, segmented and reconstructed three-dimensionally. The image data were neuronavigationally transferred into the operative field, and provided the neurosurgeon with information on lesion site and adjacent OR localization. Preoperative and postoperative neuroophthalmological testing included, among others, perimetry to define the value of diffusion-weighted image guidance during OR lesion resection. Three lesions were removed completely. In one case, low-grade tumor parts infiltrating the OR were intentionally left. No persistent visual field deficits were induced. In one patient, a transient homonymous hemianopia attributable to postoperative swelling completely resolved under steroid medication. The authors conclude that intraoperative OR visualization, realized by neuronavigationally displayed DWI data, might prove to be helpful to maintain patients' visual fields.
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Affiliation(s)
- V A Coenen
- Department of Neurosurgery, University Hospital, Aachen University (RWTH), Aachen, Germany.
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Nimsky C, Ganslandt O, Hastreiter P, Wang R, Benner T, Sorensen AG, Fahlbusch R. Intraoperative diffusion-tensor MR imaging: shifting of white matter tracts during neurosurgical procedures--initial experience. Radiology 2004; 234:218-25. [PMID: 15564394 DOI: 10.1148/radiol.2341031984] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To prospectively evaluate the location of white matter tracts with diffusion-tensor imaging (DTI) during neurosurgical procedures. MATERIALS AND METHODS Ethical committee approval and signed informed consent were obtained. A 1.5-T magnetic resonance imager with an adapted rotating surgical table that is placed in a radiofrequency-shielded operating theater was used for pre- and intraoperative imaging. DTI was performed by applying an echo-planar imaging sequence with six diffusion directions in 38 patients (20 female patients, 18 male patients; age range, 7-77 years; mean age, 45.6 years) who were undergoing surgery (35 craniotomy and three burr hole procedures). Color-encoded maps of fractional anisotropy were generated by depicting white matter tracts. A rigid registration algorithm was used to compare pre- and intraoperative images. RESULTS Intraoperative DTI was technically feasible in all patients, and no major image distortions occurred in the areas of interest. Pre- and intraoperative color-encoded maps of fractional anisotropy could be registered; these maps depicted marked and highly variable shifting of white matter tracts during neurosurgical procedures. In the 27 patients who underwent brain tumor resection, white matter tract shifting ranged from an inward shift of 8 mm to an outward shift of 15 mm (mean shift +/- standard deviation, outward shift of 2.5 mm +/- 5.8). In 16 (59%) of 27 patients, outward shifting was detected; in eight (30%), inward shifting was detected. In eight patients who underwent temporal lobe resections for drug-resistant epilepsy, shifting was only inward and ranged from 2 to 14 mm (9 mm +/- 3.3). In two of the three patients who underwent burr hole procedures, outward shifting occurred. CONCLUSION Intraoperative DTI can depict shifting of major white matter tracts that is caused by surgical intervention.
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Affiliation(s)
- Christopher Nimsky
- Department of Neurosurgery, University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany.
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Nimsky C, Ganslandt O, Von Keller B, Romstöck J, Fahlbusch R. Intraoperative high-field-strength MR imaging: implementation and experience in 200 patients. Radiology 2004; 233:67-78. [PMID: 15317949 DOI: 10.1148/radiol.2331031352] [Citation(s) in RCA: 220] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
PURPOSE To review the initial clinical experience with intraoperative high-field-strength magnetic resonance (MR) imaging of brain lesions in 200 patients. MATERIALS AND METHODS Two hundred patients (mean age, 46.1 years; range, 7-84 years), most of whom had glioma or pituitary adenoma, were examined with a 1.5-T MR imager equipped with a rotating operating table and located in a radiofrequency-shielded operating theater. A navigation microscope placed inside the 0.5-mT zone and used in combination with a ceiling-mounted navigation system enabled integrated microscope-based neuronavigation. The extent of resection depicted at intraoperative imaging, the surgical consequences of intraoperative imaging, and the clinical practicability of the operating room setup were analyzed. RESULTS Seventy-seven resections with a transsphenoidal approach, 100 craniotomies, and 23 burr-hole procedures were performed. In 55 (27.5%) of 200 patients, intraoperative MR imaging had immediate surgical consequences (eg, extension of resection in 39% of patients with pituitary adenoma or glioma). In 108 patients the navigation system was used, and for 37 of those patients, functional imaging data were integrated into the navigation system. There was nearly no difference in quality between pre- and intraoperative images. Intraoperative workflow with intraoperative patient transport for imaging was straightforward, and imaging in most cases began less than 2 minutes after sterile covering of the surgical site. No complications resulted from high-field-strength MR imaging. CONCLUSION The high-field-strength MR imager was successfully adapted for intraoperative use with the integrated neuronavigation system. Intraoperative MR imaging provided valuable information that allowed intraoperative modification of the surgical strategy.
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Affiliation(s)
- Christopher Nimsky
- Department of Neurosurgery, University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany.
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