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Kram L, Schroeder A, Meyer B, Krieg SM, Ille S. Function-guided differences of arcuate fascicle and inferior fronto-occipital fascicle tractography as diagnostic indicators for surgical risk stratification. Brain Struct Funct 2024:10.1007/s00429-024-02787-3. [PMID: 38597941 DOI: 10.1007/s00429-024-02787-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 03/05/2024] [Indexed: 04/11/2024]
Abstract
BACKGROUND Several patients with language-eloquent gliomas face language deterioration postoperatively. Persistent aphasia is frequently associated with damage to subcortical language pathways. Underlying mechanisms still need to be better understood, complicating preoperative risk assessment. This study compared qualitative and quantitative functionally relevant subcortical differences pre- and directly postoperatively in glioma patients with and without aphasia. METHODS Language-relevant cortical sites were defined using navigated transcranial magnetic stimulation (nTMS) language mapping in 74 patients between 07/2016 and 07/2019. Post-hoc nTMS-based diffusion tensor imaging tractography was used to compare a tract's pre- and postoperative visualization, volume and fractional anisotropy (FA), and the preoperative distance between tract and lesion and postoperative overlap with the resection cavity between the following groups: no aphasia (NoA), tumor- or previous resection induced aphasia persistent pre- and postoperatively (TIA_P), and surgery-induced transient or permanent aphasia (SIA_T or SIA_P). RESULTS Patients with NoA, TIA_P, SIA_T, and SIA_P showed distinct fasciculus arcuatus (AF) and inferior-fronto-occipital fasciculus (IFOF) properties. The AF was more frequently reconstructable, and the FA of IFOF was higher in NoA than TIA_P cases (all p ≤ 0.03). Simultaneously, SIA_T cases showed higher IFOF fractional anisotropy than TIA_P cases (p < 0.001) and the most considerable AF volume loss overall. While not statistically significant, the four SIA_P cases showed complete loss of ventral language streams postoperatively, the highest resection-cavity-AF-overlap, and the shortest AF to tumor distance. CONCLUSION Functionally relevant qualitative and quantitative differences in AF and IFOF provide a pre- and postoperative pathophysiological and clinically relevant diagnostic indicator that supports surgical risk stratification.
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Affiliation(s)
- Leonie Kram
- Department of Neurosurgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany
- Department of Neurosurgery, Heidelberg University Hospital, Ruprecht-Karls-University, Heidelberg, Germany
| | - Axel Schroeder
- Department of Neurosurgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany
| | - Bernhard Meyer
- Department of Neurosurgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany
| | - Sandro M Krieg
- Department of Neurosurgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany
- Department of Neurosurgery, Heidelberg University Hospital, Ruprecht-Karls-University, Heidelberg, Germany
| | - Sebastian Ille
- Department of Neurosurgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany.
- Department of Neurosurgery, Heidelberg University Hospital, Ruprecht-Karls-University, Heidelberg, Germany.
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Becker D, Scherer M, Neher P, Jungk C, Jesser J, Pflüger I, Bendszus M, Maier-Hein K, Unterberg A. Q-ball high-resolution fiber tractography of language associated tracts: quantitative evaluation of applicability for glioma resections. J Neurosurg Sci 2024; 68:1-12. [PMID: 31680507 DOI: 10.23736/s0390-5616.19.04782-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND To date, fiber tractography (FT) is predominantly based on diffusion tensor imaging (DTI). High angular resolution diffusion imaging (HARDI)-based reconstructions have become a focus of interest, enabling the resolution of intravoxel fiber crossing. However, experience with high resolution tractography (HRFT) for neurosurgical applications is still limited to a few reports. This prospectively designed feasibility study shares our initial experience using an analytical q-ball approach (QBI) for FT of language-associated pathways in comparison with DTI-FT, focussing on a quantitative analysis and evaluation of its applicability in clinical routine. METHODS Probabilistic QBI-, and DTI-FT were performed for the major components of the language-associated fiber bundles (superior longitudinal fasciculus, inferior fronto-occipital fasciculus, medial/inferior longitudinal faciculus) in 11 patients with eloquent gliomas. The data was derived from a routine DWI sequence (b=1000s/mm2, 64 gradient directions). Quantitative analysis evaluated tract volume (TV), tract length (TL) and tract density (TD). Results were correlated to tumor and edema size. RESULTS Quantitative analysis showed larger TV and TL of the overall fiber object using QBI-FT compared with DTI-FT (TV: 16.45±1.85 vs. 10.07±1.15cm3; P<0.0001; TL: 81.95±6.14 vs. 72.06±6.92 mm; P=0.0011). Regarding overall TD, DTI delivered significantly higher values (40.57±6.59 vs. 60.98±15.94 points/voxel; P=0.0118). Bland-Altman analysis illustrated a systematic advantage to yield lager TV and TL via QBI compared with DTI for all reconstructed pathways. The results were independent of tumor or edema volume. CONCLUSIONS QBI proved to be suitable for an application in the neurosurgical setting without additional expense for the patient. Quantitative analysis of FT reveals larger overall TV, longer TL with lower TD using QBI compared with DTI, suggesting the better depiction of marginal and terminal fibers according to neuroanatomical knowledge. This emphasizes the known limitation of DTI to underestimate the dimensions of a pathway. Rather than relying on DTI, sophisticated HRFT techniques should be considered for preoperative planning and intraoperative guidance in selected cases of eloquent glioma surgery.
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Affiliation(s)
- Daniela Becker
- Department of Neurosurgery, University of Heidelberg, Heidelberg, Germany -
| | - Moritz Scherer
- Department of Neurosurgery, University of Heidelberg, Heidelberg, Germany
| | - Peter Neher
- Division of Medical Image Computing, German Cancer Research Center, Heidelberg, Germany
| | - Christine Jungk
- Department of Neurosurgery, University of Heidelberg, Heidelberg, Germany
| | - Jessica Jesser
- Department of Neuroradiology, University of Heidelberg, Heidelberg, Germany
| | - Irada Pflüger
- Department of Neuroradiology, University of Heidelberg, Heidelberg, Germany
| | - Martin Bendszus
- Department of Neuroradiology, University of Heidelberg, Heidelberg, Germany
| | - Klaus Maier-Hein
- Division of Medical Image Computing, German Cancer Research Center, Heidelberg, Germany
| | - Andreas Unterberg
- Department of Neurosurgery, University of Heidelberg, Heidelberg, Germany
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Eibl T, Schrey M, Liebert A, Ritter L, Lange R, Steiner HH, Schebesch KM. Influence of clinical and tumor-specific factors on the resting motor threshold in navigated transcranial magnetic stimulation. Neurophysiol Clin 2023; 53:102920. [PMID: 37944292 DOI: 10.1016/j.neucli.2023.102920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/27/2023] [Accepted: 10/28/2023] [Indexed: 11/12/2023] Open
Abstract
OBJECTIVE Preoperative non-invasive mapping of motor function with navigated transcranial magnetic stimulation (nTMS) has become a widely used diagnostic procedure. Determination of the patient-individual resting motor threshold (rMT) is of great importance to achieve reliable results when conducting nTMS motor mapping. Factors which contribute to differences in rMT of brain tumor patients have not been fully investigated. METHODS We included adult patients with all types of de novo and recurrent intracranial lesions, suspicious for intra-axial brain tumors. The outcome measure was the rMT of the upper extremity, defined as the stimulation intensity eliciting motor evoked potentials with amplitudes greater than 50µV in 50 % of applied stimulations. RESULTS Eighty nTMS examinations in 75 patients (37.5 % female) aged 57.9 ± 14.9 years were evaluated. In non-parametric testing, rMT values were higher in patients with upper extremity paresis (p = 0.024) and lower in patients with high grade gliomas (HGG) (p = 0.001). rMT inversely correlated with patient age (rs=-0.28, p = 0.013) and edema volume (rs=-0.28, p = 0.012) In regression analysis, infiltration of the precentral gyrus (p<0.001) increased rMT values. Values of rMT were reduced in high grade gliomas (p<0.001), in patients taking Levetiracetam (p = 0.019) and if perilesional edema infiltrated motor eloquent brain (p<0.001). Subgroup analyses of glioma patients revealed similar results. Values of rMT did not differ between hand and forearm muscles. CONCLUSION Most factors confounding rMT in our study were specific to the lesion. These factors contributed to the variability in cortical excitability and must be considered in clinical work with nTMS to achieve reliable results with nTMS motor mapping.
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Affiliation(s)
- Thomas Eibl
- Department of Neurosurgery, Paracelsus Medical University Nuremberg, Germany.
| | - Michael Schrey
- Department of Neurosurgery, Paracelsus Medical University Nuremberg, Germany
| | - Adrian Liebert
- Department of Neurosurgery, Paracelsus Medical University Nuremberg, Germany
| | - Leonard Ritter
- Department of Neurosurgery, Paracelsus Medical University Nuremberg, Germany
| | - Rüdiger Lange
- Department of Neurology, Paracelsus Medical University Nuremberg, Germany
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Ordonez-Rubiano EG, Johnson JM, Abdalá-Vargas N, Zorro OF, Marin-Munoz JH, Álvarez-Tobián R, Forlizzi V, Rangel CC, Luzzi S, Campero A, Patiño-Gómez JG, Baldoncini M. Preoperative tractography algorithm for safe resection of tumors located in the descending motor pathways zone. Surg Neurol Int 2023; 14:255. [PMID: 37560574 PMCID: PMC10408624 DOI: 10.25259/sni_230_2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 07/07/2023] [Indexed: 08/11/2023] Open
Abstract
BACKGROUND Diffusion tensor imaging (DTI) tractography facilitates maximal safe resection and optimizes planning to avoid injury during subcortical dissection along descending motor pathways (DMPs). We provide an affordable, safe, and timely algorithm for preoperative DTI motor reconstruction for gliomas adjacent to DMPs. METHODS Preoperative DTI reconstructions were extracted from a prospectively acquired registry of glioma resections adjacent to DMPs. The surgeries were performed over a 7-year period. Demographic, clinical, and radiographic data were extracted from patients' electronic medical records. RESULTS Nineteen patients (12 male) underwent preoperative tractography between January 1, 2013, and May 31, 2020. The average age was 44.5 years (range, 19-81 years). A complete radiological resection was achieved in nine patients, a subtotal resection in five, a partial resection in three, and a biopsy in two. Histopathological diagnoses included 10 patients with high-grade glioma and nine with low-grade glioma. A total of 16 perirolandic locations (10 frontal and six frontoparietal) were recorded, as well as two in the insula and one in the basal ganglia. In 9 patients (47.3%), the lesion was in the dominant hemisphere. The median preoperative and postoperative Karnofsky Performance Scores were 78 and 80, respectively. Motor function was unchanged or improved over time in 15 cases (78.9%). CONCLUSION This protocol of DTI reconstruction for glioma removal near the DMP shows good results in low-term neurological functional outcomes.
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Affiliation(s)
- Edgar G. Ordonez-Rubiano
- Department of Neurosurgery, Hospital de San José - Fundación Universitaria de Ciencias de la Salud, Bogota, Colombia
| | - Jason M. Johnson
- Department of Neuroradiology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States
| | - Nadin Abdalá-Vargas
- Department of Neurological Surgery, Hospital de San José - Sociedad de Cirugía de Bogotá, Colombia
| | - Oscar F. Zorro
- Department of Neurosurgery, Hospital de San José - Fundación Universitaria de Ciencias de la Salud, Bogota, Colombia
| | - Jorge H. Marin-Munoz
- Department of Neurosurgery, Hospital de San José - Fundación Universitaria de Ciencias de la Salud, Bogota, Colombia
| | - Ricardo Álvarez-Tobián
- Department of Diagnostic Imaging and Diagnostic Radiology, Fundación Universitaria de Ciencias de la Salud, Hospital Infantil Universitario de San José, Bogotá, Colombia
| | - Valeria Forlizzi
- Department of Anatomy, University of Buenos Aires, Buenos Aires, Argentina
| | - Carlos Castillo Rangel
- Department of Neurosurgery, Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado (ISSSTE), Mexico City, Mexico
| | - Sabino Luzzi
- Department of Neurosurgery, University of Pavia, Pavia, Italy
| | - Alvaro Campero
- Department of Neurosurgery, Hospital Padilla de Tucuman, Tucuman, Argentina
| | - Javier G. Patiño-Gómez
- Department of Neurosurgery, Hospital de San José - Fundación Universitaria de Ciencias de la Salud, Bogota, Colombia
| | - Matias Baldoncini
- Department of Neurosurgery, San Fernando Hospital, San Fernando, Argentina
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Ius T, Sabatino G, Panciani PP, Fontanella MM, Rudà R, Castellano A, Barbagallo GMV, Belotti F, Boccaletti R, Catapano G, Costantino G, Della Puppa A, Di Meco F, Gagliardi F, Garbossa D, Germanò AF, Iacoangeli M, Mortini P, Olivi A, Pessina F, Pignotti F, Pinna G, Raco A, Sala F, Signorelli F, Sarubbo S, Skrap M, Spena G, Somma T, Sturiale C, Angileri FF, Esposito V. Surgical management of Glioma Grade 4: technical update from the neuro-oncology section of the Italian Society of Neurosurgery (SINch®): a systematic review. J Neurooncol 2023; 162:267-293. [PMID: 36961622 PMCID: PMC10167129 DOI: 10.1007/s11060-023-04274-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 02/20/2023] [Indexed: 03/25/2023]
Abstract
PURPOSE The extent of resection (EOR) is an independent prognostic factor for overall survival (OS) in adult patients with Glioma Grade 4 (GG4). The aim of the neuro-oncology section of the Italian Society of Neurosurgery (SINch®) was to provide a general overview of the current trends and technical tools to reach this goal. METHODS A systematic review was performed. The results were divided and ordered, by an expert team of surgeons, to assess the Class of Evidence (CE) and Strength of Recommendation (SR) of perioperative drugs management, imaging, surgery, intraoperative imaging, estimation of EOR, surgery at tumor progression and surgery in elderly patients. RESULTS A total of 352 studies were identified, including 299 retrospective studies and 53 reviews/meta-analysis. The use of Dexamethasone and the avoidance of prophylaxis with anti-seizure medications reached a CE I and SR A. A preoperative imaging standard protocol was defined with CE II and SR B and usefulness of an early postoperative MRI, with CE II and SR B. The EOR was defined the strongest independent risk factor for both OS and tumor recurrence with CE II and SR B. For intraoperative imaging only the use of 5-ALA reached a CE II and SR B. The estimation of EOR was established to be fundamental in planning postoperative adjuvant treatments with CE II and SR B and the stereotactic image-guided brain biopsy to be the procedure of choice when an extensive surgical resection is not feasible (CE II and SR B). CONCLUSIONS A growing number of evidences evidence support the role of maximal safe resection as primary OS predictor in GG4 patients. The ongoing development of intraoperative techniques for a precise real-time identification of peritumoral functional pathways enables surgeons to maximize EOR minimizing the post-operative morbidity.
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Affiliation(s)
- Tamara Ius
- Division of Neurosurgery, Head-Neck and NeuroScience Department, University Hospital of Udine, Udine, Italy
| | - Giovanni Sabatino
- Institute of Neurosurgery, Fondazione Policlinico Gemelli, Catholic University, Rome, Italy
- Unit of Neurosurgery, Mater Olbia Hospital, Olbia, Italy
| | - Pier Paolo Panciani
- Division of Neurosurgery, Department of Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, Brescia, Italy.
| | - Marco Maria Fontanella
- Department of Neuro-Oncology, University of Turin and City of Health and Science Hospital, 10094, Torino, Italy
| | - Roberta Rudà
- Department of Neuro-Oncology, University of Turin and City of Health and Science Hospital, 10094, Torino, Italy
- Neurology Unit, Hospital of Castelfranco Veneto, 31033, Castelfranco Veneto, Italy
| | - Antonella Castellano
- Department of Neuroradiology, San Raffaele Scientific Institute, Vita-Salute University, Milan, Italy
| | - Giuseppe Maria Vincenzo Barbagallo
- Department of Medical and Surgical Sciences and Advanced Technologies (G.F. Ingrassia), Neurological Surgery, Policlinico "G. Rodolico - San Marco" University Hospital, University of Catania, Catania, Italy
- Interdisciplinary Research Center On Brain Tumors Diagnosis and Treatment, University of Catania, Catania, Italy
| | - Francesco Belotti
- Division of Neurosurgery, Department of Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, Brescia, Italy
| | | | - Giuseppe Catapano
- Division of Neurosurgery, Department of Neurological Sciences, Ospedale del Mare, Naples, Italy
| | | | - Alessandro Della Puppa
- Neurosurgical Clinical Department of Neuroscience, Psychology, Pharmacology and Child Health, Careggi Hospital, University of Florence, Florence, Italy
| | - Francesco Di Meco
- Department of Neurosurgery, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- Johns Hopkins Medical School, Baltimore, MD, USA
| | - Filippo Gagliardi
- Department of Neurosurgery and Gamma Knife Radiosurgery, San Raffaele Scientific Institute, Vita-Salute University, Milan, Italy
| | - Diego Garbossa
- Department of Neuroscience "Rita Levi Montalcini," Neurosurgery Unit, University of Turin, Torino, Italy
| | | | - Maurizio Iacoangeli
- Department of Neurosurgery, Università Politecnica Delle Marche, Azienda Ospedali Riuniti, Ancona, Italy
| | - Pietro Mortini
- Department of Neurosurgery and Gamma Knife Radiosurgery, San Raffaele Scientific Institute, Vita-Salute University, Milan, Italy
| | | | - Federico Pessina
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, 20090, Milan, Italy
- Neurosurgery Department, IRCCS Humanitas Research Hospital, Via Manzoni 56, 20089, Milan, Italy
| | - Fabrizio Pignotti
- Institute of Neurosurgery, Fondazione Policlinico Gemelli, Catholic University, Rome, Italy
- Unit of Neurosurgery, Mater Olbia Hospital, Olbia, Italy
| | - Giampietro Pinna
- Unit of Neurosurgery, Department of Neurosciences, Hospital Trust of Verona, 37134, Verona, Italy
| | - Antonino Raco
- Division of Neurosurgery, Department of NESMOS, AOU Sant'Andrea, Sapienza University, Rome, Italy
| | - Francesco Sala
- Department of Neurosciences, Biomedicines and Movement Sciences, Institute of Neurosurgery, University of Verona, 37134, Verona, Italy
| | - Francesco Signorelli
- Department of Basic Medical Sciences, Neuroscience and Sense Organs, Neurosurgery Unit, University "Aldo Moro", 70124, Bari, Italy
| | - Silvio Sarubbo
- Department of Neurosurgery, Santa Chiara Hospital, Azienda Provinciale Per I Servizi Sanitari (APSS), Trento, Italy
| | - Miran Skrap
- Division of Neurosurgery, Head-Neck and NeuroScience Department, University Hospital of Udine, Udine, Italy
| | | | - Teresa Somma
- Division of Neurosurgery, Department of Neurosciences, Reproductive and Odontostomatological Sciences, Università Degli Studi Di Napoli Federico II, Naples, Italy
| | | | | | - Vincenzo Esposito
- Department of Neurosurgery "Giampaolo Cantore"-IRCSS Neuromed, Pozzilli, Italy
- Department of Human, Neurosciences-"Sapienza" University of Rome, Rome, Italy
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6
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Zhylka A, Leemans A, Pluim JPW, De Luca A. Anatomically informed multi-level fiber tractography for targeted virtual dissection. MAGMA (NEW YORK, N.Y.) 2023; 36:79-93. [PMID: 35904612 PMCID: PMC9992235 DOI: 10.1007/s10334-022-01033-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 06/30/2022] [Accepted: 07/15/2022] [Indexed: 12/01/2022]
Abstract
OBJECTIVES Diffusion-weighted MRI can assist preoperative planning by reconstructing the trajectory of eloquent fiber pathways, such as the corticospinal tract (CST). However, accurate reconstruction of the full extent of the CST remains challenging with existing tractography methods. We suggest a novel tractography algorithm exploiting unused fiber orientations to produce more complete and reliable results. METHODS Our novel approach, referred to as multi-level fiber tractography (MLFT), reconstructs fiber pathways by progressively considering previously unused fiber orientations at multiple levels of tract propagation. Anatomical priors are used to minimize the number of false-positive pathways. The MLFT method was evaluated on synthetic data and in vivo data by reconstructing the CST while compared to conventional tractography approaches. RESULTS The radial extent of MLFT reconstructions is comparable to that of probabilistic reconstruction: [Formula: see text] for the left and [Formula: see text] for the right hemisphere according to Wilcoxon test, while achieving significantly higher topography preservation compared to probabilistic tractography: [Formula: see text]. DISCUSSION MLFT provides a novel way to reconstruct fiber pathways by adding the capability of including branching pathways in fiber tractography. Thanks to its robustness, feasible reconstruction extent and topography preservation, our approach may assist in clinical practice as well as in virtual dissection studies.
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Affiliation(s)
- Andrey Zhylka
- Biomedical Engineering, Eindhoven University of Technology, Rondom 70, 5612 AP, Eindhoven, The Netherlands.
| | - Alexander Leemans
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Josien P W Pluim
- Biomedical Engineering, Eindhoven University of Technology, Rondom 70, 5612 AP, Eindhoven, The Netherlands
| | - Alberto De Luca
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands.,Neurology Department, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht, The Netherlands
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7
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Zhang W, Ille S, Schwendner M, Wiestler B, Meyer B, Krieg SM. Tracking motor and language eloquent white matter pathways with intraoperative fiber tracking versus preoperative tractography adjusted by intraoperative MRI-based elastic fusion. J Neurosurg 2022; 137:1114-1123. [PMID: 35213839 DOI: 10.3171/2021.12.jns212106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 12/09/2021] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Preoperative fiber tracking (FT) enables visualization of white matter pathways. However, the intraoperative accuracy of preoperative image registration is reduced due to brain shift. Intraoperative FT is currently considered the standard of anatomical accuracy, while intraoperative imaging can also be used to correct and update preoperative data by intraoperative MRI (ioMRI)-based elastic fusion (IBEF). However, the use of intraoperative tractography is restricted due to the need for additional acquisition of diffusion imaging in addition to scanner limitations, quality factors, and setup time. Since IBEF enables compensation for brain shift and updating of preoperative FT, the aim of this study was to compare intraoperative FT with IBEF of preoperative FT. METHODS Preoperative MRI (pMRI) and ioMRI, both including diffusion tensor imaging (DTI) data, were acquired between February and November 2018. Anatomy-based DTI FT of the corticospinal tract (CST) and the arcuate fascicle (AF) was reconstructed at various fractional anisotropy (FA) values on pMRI and ioMRI, respectively. The intraoperative DTI FT, as a baseline tractography, was fused with original preoperative FT and IBEF-compensated FT, processes referred to as rigid fusion (RF) and elastic fusion (EF), respectively. The spatial overlap index (Dice coefficient [DICE]) and distances of surface points (average surface distance [ASD]) of fused FT before and after IBEF were analyzed and compared in operated and nonoperated hemispheres. RESULTS Seventeen patients with supratentorial brain tumors were analyzed. On the operated hemisphere, the overlap index of pre- and intraoperative FT of the CST by DICE significantly increased by 0.09 maximally after IBEF. A significant decrease by 0.5 mm maximally in the fused FT presented by ASD was observed. Similar improvements were found in IBEF-compensated FT, for which AF tractography on the tumor hemispheres increased by 0.03 maximally in DICE and decreased by 1.0 mm in ASD. CONCLUSIONS Preoperative tractography after IBEF is comparable to intraoperative tractography and can be a reliable alternative to intraoperative FT.
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Affiliation(s)
| | | | | | - Benedikt Wiestler
- 2Diagnostic and Interventional Neuroradiology, Technical University of Munich School of Medicine, Munich, Germany
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8
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Carrabba G, Fiore G, Di Cristofori A, Bana C, Borellini L, Zarino B, Conte G, Triulzi F, Rocca A, Giussani C, Caroli M, Locatelli M, Bertani G. Diffusion tensor imaging, intra-operative neurophysiological monitoring and small craniotomy: Results in a consecutive series of 103 gliomas. Front Oncol 2022; 12:897147. [PMID: 36176387 PMCID: PMC9513471 DOI: 10.3389/fonc.2022.897147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 07/14/2022] [Indexed: 11/13/2022] Open
Abstract
Diffusion tensor imaging (DTI) allows visualization of the main white matter tracts while intraoperative neurophysiological monitoring (IONM) represents the gold standard for surgical resection of gliomas. In recent years, the use of small craniotomies has gained popularity thanks to neuronavigation and to the low morbidity rates associated with shorter surgical procedures. The aim of this study was to review a series of patients operated for glioma using DTI, IONM, and tumor-targeted craniotomies. The retrospective analysis included patients with supratentorial glioma who met the following inclusion criteria: preoperative DTI, intraoperative IONM, tumor-targeted craniotomy, pre- and postoperative MRI, and complete clinical charts. The DTI was performed on a 3T scanner. The IONM included electroencephalography (EEG), transcranial (TC) and/or cortical motor-evoked potentials (MEP), electrocorticography (ECoG), and direct electrical stimulation (DES). Outcomes included postoperative neurological deficits, volumetric extent of resection (EOR), and overall survival (OS). One hundred and three patients (61 men, 42 women; mean age 54 ± 14 years) were included and presented the following WHO histologies: 65 grade IV, 19 grade III, and 19 grade II gliomas. After 3 months, only three patients had new neurological deficits. The median postoperative volume was 0cc (IQR 3). The median OS for grade IV gliomas was 15 months, while for low-grade gliomas it was not reached. In our experience, a small craniotomy and a tumor resection supported by IONM and DTI permitted to achieve satisfactory results in terms of neurological outcomes, EOR, and OS for glioma patients.
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Affiliation(s)
- Giorgio Carrabba
- Neurosugery, Azienda Socio Sanitaria Territoriale Monza - Ospedale San Gerardo di Monza, Monza, Italy
- Dipartimento di Medicina e Chirurgia, Università degli Studi di Milano-Bicocca, Milan, Italy
- *Correspondence: Giorgio Carrabba,
| | - Giorgio Fiore
- Neurosurgery, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
| | - Andrea Di Cristofori
- Neurosugery, Azienda Socio Sanitaria Territoriale Monza - Ospedale San Gerardo di Monza, Monza, Italy
| | - Cristina Bana
- Neurophysiopathology, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milano, Italy
| | - Linda Borellini
- Neurophysiopathology, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milano, Italy
| | - Barbara Zarino
- Neurosurgery, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
| | - Giorgio Conte
- Neuroradiology, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, University of Milano, Milano, Italy
| | - Fabio Triulzi
- Neuroradiology, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, University of Milano, Milano, Italy
| | - Alessandra Rocca
- Neurosugery, Azienda Socio Sanitaria Territoriale Monza - Ospedale San Gerardo di Monza, Monza, Italy
- Dipartimento di Medicina e Chirurgia, Università degli Studi di Milano-Bicocca, Milan, Italy
| | - Carlo Giussani
- Neurosugery, Azienda Socio Sanitaria Territoriale Monza - Ospedale San Gerardo di Monza, Monza, Italy
- Dipartimento di Medicina e Chirurgia, Università degli Studi di Milano-Bicocca, Milan, Italy
| | - Manuela Caroli
- Neurosurgery, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
| | - Marco Locatelli
- Neurosurgery, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
- Department of Medical-Surgical Physiopathology and Transplantation, University of Milan, Milan, Italy
| | - Giulio Bertani
- Neurosurgery, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
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9
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Cognitive deficits in adult patients with high-grade glioma: A systematic review. Clin Neurol Neurosurg 2022; 219:107296. [DOI: 10.1016/j.clineuro.2022.107296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 04/04/2022] [Accepted: 05/13/2022] [Indexed: 11/15/2022]
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10
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Zhang F, Daducci A, He Y, Schiavi S, Seguin C, Smith RE, Yeh CH, Zhao T, O'Donnell LJ. Quantitative mapping of the brain's structural connectivity using diffusion MRI tractography: A review. Neuroimage 2022; 249:118870. [PMID: 34979249 PMCID: PMC9257891 DOI: 10.1016/j.neuroimage.2021.118870] [Citation(s) in RCA: 88] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 12/03/2021] [Accepted: 12/31/2021] [Indexed: 12/13/2022] Open
Abstract
Diffusion magnetic resonance imaging (dMRI) tractography is an advanced imaging technique that enables in vivo reconstruction of the brain's white matter connections at macro scale. It provides an important tool for quantitative mapping of the brain's structural connectivity using measures of connectivity or tissue microstructure. Over the last two decades, the study of brain connectivity using dMRI tractography has played a prominent role in the neuroimaging research landscape. In this paper, we provide a high-level overview of how tractography is used to enable quantitative analysis of the brain's structural connectivity in health and disease. We focus on two types of quantitative analyses of tractography, including: 1) tract-specific analysis that refers to research that is typically hypothesis-driven and studies particular anatomical fiber tracts, and 2) connectome-based analysis that refers to research that is more data-driven and generally studies the structural connectivity of the entire brain. We first provide a review of methodology involved in three main processing steps that are common across most approaches for quantitative analysis of tractography, including methods for tractography correction, segmentation and quantification. For each step, we aim to describe methodological choices, their popularity, and potential pros and cons. We then review studies that have used quantitative tractography approaches to study the brain's white matter, focusing on applications in neurodevelopment, aging, neurological disorders, mental disorders, and neurosurgery. We conclude that, while there have been considerable advancements in methodological technologies and breadth of applications, there nevertheless remains no consensus about the "best" methodology in quantitative analysis of tractography, and researchers should remain cautious when interpreting results in research and clinical applications.
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Affiliation(s)
- Fan Zhang
- Brigham and Women's Hospital, Harvard Medical School, Boston, USA.
| | | | - Yong He
- State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China; Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China; IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China; Chinese Institute for Brain Research, Beijing, China
| | - Simona Schiavi
- Department of Computer Science, University of Verona, Verona, Italy
| | - Caio Seguin
- Melbourne Neuropsychiatry Centre, University of Melbourne and Melbourne Health, Melbourne, Australia; The University of Sydney, School of Biomedical Engineering, Sydney, Australia
| | - Robert E Smith
- The Florey Institute of Neuroscience and Mental Health, Melbourne, Australia; Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia
| | - Chun-Hung Yeh
- Institute for Radiological Research, Chang Gung University, Taoyuan, Taiwan; Department of Psychiatry, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan
| | - Tengda Zhao
- State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China; Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China; IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
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11
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Giampiccolo D, Nunes S, Cattaneo L, Sala F. Functional Approaches to the Surgery of Brain Gliomas. Adv Tech Stand Neurosurg 2022; 45:35-96. [PMID: 35976447 DOI: 10.1007/978-3-030-99166-1_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In the surgery of gliomas, recent years have witnessed unprecedented theoretical and technical development, which extensively increased indication to surgery. On one hand, it has been solidly demonstrated the impact of gross total resection on life expectancy. On the other hand, the paradigm shift from classical cortical localization of brain function towards connectomics caused by the resurgence of awake surgery and the advent of tractography has permitted safer surgeries focused on subcortical white matter tracts preservation and allowed for surgical resections within regions, such as Broca's area or the primary motor cortex, which were previously deemed inoperable. Furthermore, new asleep electrophysiological techniques have been developed whenever awake surgery is not an option, such as operating in situations of poor compliance (including paediatric patients) or pre-existing neurological deficits. One such strategy is the use of intraoperative neurophysiological monitoring (IONM), enabling the identification and preservation of functionally defined, but anatomically ambiguous, cortico-subcortical structures through mapping and monitoring techniques. These advances tie in with novel challenges, specifically risk prediction and the impact of neuroplasticity, the indication for tumour resection beyond visible borders, or supratotal resection, and most of all, a reappraisal of the importance of the right hemisphere from early psychosurgery to mapping and preservation of social behaviour, executive control, and decision making.Here we review current advances and future perspectives in a functional approach to glioma surgery.
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Affiliation(s)
- Davide Giampiccolo
- Section of Neurosurgery, Department of Neurosciences, Biomedicine and Movement Sciences, University Hospital, University of Verona, Verona, Italy
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London, UK
- Victor Horsley Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London, UK
- Institute of Neurosciences, Cleveland Clinic London, London, UK
| | - Sonia Nunes
- Section of Neurosurgery, Department of Neurosciences, Biomedicine and Movement Sciences, University Hospital, University of Verona, Verona, Italy
| | - Luigi Cattaneo
- Center for Mind and Brain Sciences (CIMeC) and Center for Medical Sciences (CISMed), University of Trento, Trento, Italy
| | - Francesco Sala
- Section of Neurosurgery, Department of Neurosciences, Biomedicine and Movement Sciences, University Hospital, University of Verona, Verona, Italy.
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12
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Ohlerth AK, Bastiaanse R, Negwer C, Sollmann N, Schramm S, Schröder A, Krieg SM. Benefit of Action Naming Over Object Naming for Visualization of Subcortical Language Pathways in Navigated Transcranial Magnetic Stimulation-Based Diffusion Tensor Imaging-Fiber Tracking. Front Hum Neurosci 2021; 15:748274. [PMID: 34803634 PMCID: PMC8603927 DOI: 10.3389/fnhum.2021.748274] [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: 07/27/2021] [Accepted: 10/11/2021] [Indexed: 11/13/2022] Open
Abstract
Visualization of functionally significant subcortical white matter fibers is needed in neurosurgical procedures in order to avoid damage to the language network during resection. In an effort to achieve this, positive cortical points revealed during preoperative language mapping with navigated transcranial magnetic stimulation (nTMS) can be employed as regions of interest (ROIs) for diffusion tensor imaging (DTI) fiber tracking. However, the effect that the use of different language tasks has on nTMS mapping and subsequent DTI-fiber tracking remains unexplored. The visualization of ventral stream tracts with an assumed lexico-semantic role may especially benefit from ROIs delivered by the lexico-semantically demanding verb task, Action Naming. In a first step, bihemispheric nTMS language mapping was administered in 18 healthy participants using the standard task Object Naming and the novel task Action Naming to trigger verbs in a small sentence context. Cortical areas in which nTMS induced language errors were identified as language-positive cortical sites. In a second step, nTMS-based DTI-fiber tracking was conducted using solely these language-positive points as ROIs. The ability of the two tasks’ ROIs to visualize the dorsal tracts Arcuate Fascicle and Superior Longitudinal Fascicle, the ventral tracts Inferior Longitudinal Fascicle, Uncinate Fascicle, and Inferior Fronto-Occipital Fascicle, the speech-articulatory Cortico-Nuclear Tract, and interhemispheric commissural fibers was compared in both hemispheres. In the left hemisphere, ROIs of Action Naming led to a significantly higher fraction of overall visualized tracts, specifically in the ventral stream’s Inferior Fronto-Occipital and Inferior Longitudinal Fascicle. No difference was found between tracking with Action Naming vs. Object Naming seeds for dorsal stream tracts, neither for the speech-articulatory tract nor the inter-hemispheric connections. While the two tasks appeared equally demanding for phonological-articulatory processes, ROI seeding through the task Action Naming seemed to better visualize lexico-semantic tracts in the ventral stream. This distinction was not evident in the right hemisphere. However, the distribution of tracts exposed was, overall, mirrored relative to those in the left hemisphere network. In presurgical practice, mapping and tracking of language pathways may profit from these findings and should consider inclusion of the Action Naming task, particularly for lesions in ventral subcortical regions.
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Affiliation(s)
- Ann-Katrin Ohlerth
- Center for Language and Cognition Groningen, University of Groningen, Groningen, Netherlands.,International Doctorate for Experimental Approaches to Language and Brain (IDEALAB), University of Groningen, Groningen, Netherlands
| | - Roelien Bastiaanse
- Center for Language and Brain, National Research University Higher School of Economics, Moscow, Russia
| | - Chiara Negwer
- Department of Neurosurgery, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - Nico Sollmann
- Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.,TUM-Neuroimaging Center, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.,Department of Diagnostic and Interventional Radiology, University Hospital Ulm, Ulm, Germany
| | - Severin Schramm
- Department of Neurosurgery, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - Axel Schröder
- Department of Neurosurgery, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - Sandro M Krieg
- Department of Neurosurgery, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.,TUM-Neuroimaging Center, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
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13
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Fang S, Liang Y, Li L, Wang L, Fan X, Wang Y, Jiang T. Tumor location-based classification of surgery-related language impairments in patients with glioma. J Neurooncol 2021; 155:143-152. [PMID: 34599481 DOI: 10.1007/s11060-021-03858-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 09/27/2021] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Many patients with glioma experience surgery-related language impairment. This study developed a classification system to predict postoperative language prognosis. METHODS Sixty-eight patients were retrospectively reviewed. Based on their location, tumors were subtyped as follows: (I) inferior frontal lobe or precentral gyrus; (II) posterior central gyrus or supramarginal gyrus (above the lateral fissure level); (III) posterior region of the superior or middle temporal gyri or supramarginal gyrus (below the lateral fissure level); and (IV) insular lobe. The distance from the tumor to the superior longitudinal fasciculus/arcuate fasciculus was calculated. The recovery of language function was assessed using the Western Aphasia Battery before surgery, and a comprehensive language test was conducted on the day of surgery; 3, 7, and 14 days after surgery. Our follow-up information of was the comprehensive language test from telephone interviews in 3 months after surgery. RESULTS Thirty-three patients experienced transient language impairment within 1 week of surgery. Fourteen patients had permanent language impairment. Type II tumors, shorter distance from the tumor to the posterior superior longitudinal fasciculus/arcuate fasciculus, and isocitrate dehydrogenase mutations were risk factors for surgery-related language impairment. Regarding the presence or absence of permanent surgery-related language impairments, the cut-off distance between the tumor and posterior superior longitudinal fasciculus/arcuate fasciculus was 2.75 mm. CONCLUSIONS According to our classification, patients with type II tumors had the worst language prognosis and longest recovery time. Our classification, based on tumor location, can reliably predict postoperative language status and may be used to guide tumor resection.
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Affiliation(s)
- Shengyu Fang
- Beijing Neurosurgical Institute, Capital Medical University, 119, the Western Road of the southern 4th Ring Road, Beijing, 100070, China
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, 119, the Western Road of the southern 4th Ring Road, Beijing, 100070, China
| | - Yuchao Liang
- Beijing Neurosurgical Institute, Capital Medical University, 119, the Western Road of the southern 4th Ring Road, Beijing, 100070, China
| | - Lianwang Li
- Beijing Neurosurgical Institute, Capital Medical University, 119, the Western Road of the southern 4th Ring Road, Beijing, 100070, China
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, 119, the Western Road of the southern 4th Ring Road, Beijing, 100070, China
| | - Lei Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, 119, the Western Road of the southern 4th Ring Road, Beijing, 100070, China
| | - Xing Fan
- Beijing Neurosurgical Institute, Capital Medical University, 119, the Western Road of the southern 4th Ring Road, Beijing, 100070, China.
| | - Yinyan Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, 119, the Western Road of the southern 4th Ring Road, Beijing, 100070, China.
| | - Tao Jiang
- Beijing Neurosurgical Institute, Capital Medical University, 119, the Western Road of the southern 4th Ring Road, Beijing, 100070, China.
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, 119, the Western Road of the southern 4th Ring Road, Beijing, 100070, China.
- Research Unit of Accurate Diagnosis, Treatment, and Translational Medicine of Brain Tumors Chinese Academy of Medical Sciences, Beijing, China.
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14
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Silva LL, Tuncer MS, Vajkoczy P, Picht T, Rosenstock T. Distinct approaches to language pathway tractography: comparison of anatomy-based, repetitive navigated transcranial magnetic stimulation (rTMS)-based, and rTMS-enhanced diffusion tensor imaging-fiber tracking. J Neurosurg 2021; 136:589-600. [PMID: 34330091 DOI: 10.3171/2020.12.jns204028] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 12/21/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Visualization of subcortical language pathways by means of diffusion tensor imaging-fiber tracking (DTI-FT) is evolving as an important tool for surgical planning and decision making in patients with language-suspect brain tumors. Repetitive navigated transcranial magnetic stimulation (rTMS) cortical language mapping noninvasively provides additional functional information. Efforts to incorporate rTMS data into DTI-FT are promising, but the lack of established protocols makes it hard to assess clinical utility. The authors performed DTI-FT of important language pathways by using five distinct approaches in an effort to evaluate the respective clinical usefulness of each approach. METHODS Thirty patients with left-hemispheric perisylvian lesions underwent preoperative rTMS language mapping and DTI. FT of the principal language tracts was conducted according to different strategies: Ia, anatomical landmark based; Ib, lesion-focused landmark based; IIa, rTMS based; IIb, rTMS based with postprocessing; and III, rTMS enhanced (based on a combination of structural and functional data). The authors analyzed the respective success of each method in revealing streamlines and conducted a multinational survey with expert clinicians to evaluate aspects of clinical utility. RESULTS The authors observed high usefulness and accuracy ratings for anatomy-based approaches (Ia and Ib). Postprocessing of rTMS-based tractograms (IIb) led to more balanced perceived information content but did not improve the usefulness for surgical planning and risk assessment. Landmark-based tractography (Ia and Ib) was most successful in delineating major language tracts (98% success), whereas rTMS-based tractography (IIa and IIb) frequently failed to reveal streamlines and provided less complete tractograms than the landmark-based approach (p < 0.001). The lesion-focused landmark-based (Ib) and the rTMS-enhanced (III) approaches were the most preferred methods. CONCLUSIONS The lesion-focused landmark-based approach (Ib) achieved the best ratings and enabled visualization of the principal language tracts in almost all cases. The rTMS-enhanced approach (III) was positively evaluated by the experts because it can reveal cortico-subcortical connections, but the functional relevance of these connections is still unclear. The use of regions of interest derived solely from cortical rTMS mapping (IIa and IIb) leads to cluttered images that are of limited use in clinical practice.
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Affiliation(s)
- Luca L Silva
- Departments of1Neurosurgery and.,2Anesthesiology and Intensive Care Medicine, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin
| | | | | | - Thomas Picht
- Departments of1Neurosurgery and.,3Cluster of Excellence: "Matters of Activity. Image Space Material"-Humboldt University, Berlin; and
| | - Tizian Rosenstock
- Departments of1Neurosurgery and.,4Berlin Institute of Health (BIH) at Charité - Universitätsmedizin Berlin, Germany
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15
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Herbet G. Should Complex Cognitive Functions Be Mapped With Direct Electrostimulation in Wide-Awake Surgery? A Network Perspective. Front Neurol 2021; 12:635439. [PMID: 33912124 PMCID: PMC8072013 DOI: 10.3389/fneur.2021.635439] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 03/17/2021] [Indexed: 12/18/2022] Open
Affiliation(s)
- Guillaume Herbet
- Institute of Functional Genomics, INSERM, CNRS, University of Montpellier, Montpellier, France.,Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France
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16
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Ille S, Schwendner M, Zhang W, Schroeder A, Meyer B, Krieg SM. Tractography for Subcortical Resection of Gliomas Is Highly Accurate for Motor and Language Function: ioMRI-Based Elastic Fusion Disproves the Severity of Brain Shift. Cancers (Basel) 2021; 13:cancers13081787. [PMID: 33918598 PMCID: PMC8068819 DOI: 10.3390/cancers13081787] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 03/29/2021] [Accepted: 04/04/2021] [Indexed: 02/07/2023] Open
Abstract
Simple Summary Tractography enables the visualization of eloquent white matter pathways. Inaccuracies due to brain shift might occur intraoperatively. The aim of this study was to evaluate the impact of intraoperative magnetic resonance imaging (MRI)-based elastic fusion on preoperative tractography for subcortical resection of gliomas. We confirmed the high accuracy of tractography during the whole course of surgery. Abstract When using preoperative tractography intraoperatively, inaccuracies due to brain shift might occur. Intraoperative tractography is rarely performed. Elastic fusion (EF) is a tool developed to compensate for brain shift, gravity, and tissue resection based on intraoperative images. Our hypothesis was that preoperative tractography is accurate and adjustments of tractography by intraoperative magnetic resonance imaging (ioMRI)-based EF (IBEF) compensate for brain shift. Between February 2018 and June 2019, 78 patients underwent eloquent (46 motor, 32 language) glioma resection in our department using intraoperative MRI. Mean distances between the resection cavity and tractography were analyzed and correlated with clinical outcomes. The mean ± standard deviation (range) distance after the application of IBEF was 5.0 ± 2.9 mm (0–10 mm) in patients without surgery-related motor deficits compared with 1.1 ± 1.6 mm (0–5 mm) in patients who showed new permanent surgery-related motor deficits postoperatively (p < 0.001). For language, the distance was 0.7 ± 1.2 mm (0–2 mm) in patients with new permanent deficits compared with 3.1 ± 4.5 mm (0–14 mm) in patients without new permanent surgery-related language deficits (p = 0.541). Preoperative tractography corrected by IBEF for subcortical resection of gliomas is highly accurate. However, at least for such subcortical anatomy, the severity of brain shift was considerably overestimated in the past.
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Affiliation(s)
- Sebastian Ille
- Department of Neurosurgery, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany; (S.I.); (M.S.); (W.Z.); (A.S.); (B.M.)
- TUM Neuroimaging Center, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany
| | - Maximilian Schwendner
- Department of Neurosurgery, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany; (S.I.); (M.S.); (W.Z.); (A.S.); (B.M.)
- TUM Neuroimaging Center, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany
| | - Wei Zhang
- Department of Neurosurgery, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany; (S.I.); (M.S.); (W.Z.); (A.S.); (B.M.)
| | - Axel Schroeder
- Department of Neurosurgery, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany; (S.I.); (M.S.); (W.Z.); (A.S.); (B.M.)
- TUM Neuroimaging Center, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany
| | - Bernhard Meyer
- Department of Neurosurgery, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany; (S.I.); (M.S.); (W.Z.); (A.S.); (B.M.)
| | - Sandro M. Krieg
- Department of Neurosurgery, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany; (S.I.); (M.S.); (W.Z.); (A.S.); (B.M.)
- TUM Neuroimaging Center, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany
- Correspondence: ; Tel.: +49-89-4140-2151
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17
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Jeltema HR, Ohlerth AK, de Wit A, Wagemakers M, Rofes A, Bastiaanse R, Drost G. Comparing navigated transcranial magnetic stimulation mapping and "gold standard" direct cortical stimulation mapping in neurosurgery: a systematic review. Neurosurg Rev 2020; 44:1903-1920. [PMID: 33009990 PMCID: PMC8338816 DOI: 10.1007/s10143-020-01397-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 09/05/2020] [Accepted: 09/17/2020] [Indexed: 12/14/2022]
Abstract
The objective of this systematic review is to create an overview of the literature on the comparison of navigated transcranial magnetic stimulation (nTMS) as a mapping tool to the current gold standard, which is (intraoperative) direct cortical stimulation (DCS) mapping. A search in the databases of PubMed, EMBASE, and Web of Science was performed. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and recommendations were used. Thirty-five publications were included in the review, describing a total of 552 patients. All studies concerned either mapping of motor or language function. No comparative data for nTMS and DCS for other neurological functions were found. For motor mapping, the distances between the cortical representation of the different muscle groups identified by nTMS and DCS varied between 2 and 16 mm. Regarding mapping of language function, solely an object naming task was performed in the comparative studies on nTMS and DCS. Sensitivity and specificity ranged from 10 to 100% and 13.3–98%, respectively, when nTMS language mapping was compared with DCS mapping. The positive predictive value (PPV) and negative predictive value (NPV) ranged from 17 to 75% and 57–100% respectively. The available evidence for nTMS as a mapping modality for motor and language function is discussed.
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Affiliation(s)
- Hanne-Rinck Jeltema
- Department of Neurosurgery, University Medical Center Groningen, Hanzeplein 1, P.O. Box 30.001, 9700 RB, Groningen, the Netherlands.
| | - Ann-Katrin Ohlerth
- Center for Language and Cognition Groningen, University of Groningen, Oude Kijk in 't Jatstraat 26, 9712 EK, Groningen, the Netherlands
| | - Aranka de Wit
- Faculty of Medical Sciences, University of Groningen, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands
| | - Michiel Wagemakers
- Department of Neurosurgery, University Medical Center Groningen, Hanzeplein 1, P.O. Box 30.001, 9700 RB, Groningen, the Netherlands
| | - Adrià Rofes
- Center for Language and Cognition Groningen, University of Groningen, Oude Kijk in 't Jatstraat 26, 9712 EK, Groningen, the Netherlands
| | - Roelien Bastiaanse
- Center for Language and Cognition Groningen, University of Groningen, Oude Kijk in 't Jatstraat 26, 9712 EK, Groningen, the Netherlands.,Center for Language and Brain, National Research University, Higher School of Economics, Moscow, Russian Federation
| | - Gea Drost
- Department of Neurosurgery, University Medical Center Groningen, Hanzeplein 1, P.O. Box 30.001, 9700 RB, Groningen, the Netherlands
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18
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Verburg N, de Witt Hamer PC. State-of-the-art imaging for glioma surgery. Neurosurg Rev 2020; 44:1331-1343. [PMID: 32607869 PMCID: PMC8121714 DOI: 10.1007/s10143-020-01337-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/25/2020] [Accepted: 06/15/2020] [Indexed: 11/29/2022]
Abstract
Diffuse gliomas are infiltrative primary brain tumors with a poor prognosis despite multimodal treatment. Maximum safe resection is recommended whenever feasible. The extent of resection (EOR) is positively correlated with survival. Identification of glioma tissue during surgery is difficult due to its diffuse nature. Therefore, glioma resection is imaging-guided, making the choice for imaging technique an important aspect of glioma surgery. The current standard for resection guidance in non-enhancing gliomas is T2 weighted or T2w-fluid attenuation inversion recovery magnetic resonance imaging (MRI), and in enhancing gliomas T1-weighted MRI with a gadolinium-based contrast agent. Other MRI sequences, like magnetic resonance spectroscopy, imaging modalities, such as positron emission tomography, as well as intraoperative imaging techniques, including the use of fluorescence, are also available for the guidance of glioma resection. The neurosurgeon’s goal is to find the balance between maximizing the EOR and preserving brain functions since surgery-induced neurological deficits result in lower quality of life and shortened survival. This requires localization of important brain functions and white matter tracts to aid the pre-operative planning and surgical decision-making. Visualization of brain functions and white matter tracts is possible with functional MRI, diffusion tensor imaging, magnetoencephalography, and navigated transcranial magnetic stimulation. In this review, we discuss the current available imaging techniques for the guidance of glioma resection and the localization of brain functions and white matter tracts.
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Affiliation(s)
- Niels Verburg
- Department of Neurosurgery and Cancer Center Amsterdam, Amsterdam UMC location VU University Medical Center, Amsterdam, The Netherlands. .,Division of Neurosurgery, Department of Clinical Neurosciences, Cambridge Brain Tumor Imaging Laboratory, University of Cambridge, Addenbrooke's Hospital, Hill Rd, Cambridge, CB2 0QQ, UK.
| | - Philip C de Witt Hamer
- Department of Neurosurgery and Cancer Center Amsterdam, Amsterdam UMC location VU University Medical Center, Amsterdam, The Netherlands
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19
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Sollmann N, Zhang H, Fratini A, Wildschuetz N, Ille S, Schröder A, Zimmer C, Meyer B, Krieg SM. Risk Assessment by Presurgical Tractography Using Navigated TMS Maps in Patients with Highly Motor- or Language-Eloquent Brain Tumors. Cancers (Basel) 2020; 12:cancers12051264. [PMID: 32429502 PMCID: PMC7281396 DOI: 10.3390/cancers12051264] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 04/29/2020] [Accepted: 05/10/2020] [Indexed: 11/30/2022] Open
Abstract
Patients with functionally eloquent brain lesions are at risk of functional decline in the course of resection. Given tumor-related plastic reshaping and reallocation of function, individual data are needed for patient counseling and risk assessment prior to surgery. This study evaluates the utility of mapping by navigated transcranial magnetic stimulation (nTMS) and nTMS-based diffusion tensor imaging fiber tracking (DTI FT) for individual risk evaluation of surgery-related decline of motor or language function in the clinical setting. In total, 250 preoperative nTMS mappings (100 language and 150 motor mappings) derived from 216 patients (mean age: 57.0 ± 15.5 years, 58.8% males; glioma World Health Organization (WHO) grade I & II: 4.2%, glioma WHO grade III & IV: 83.4%, arteriovenous malformations: 1.9%, cavernoma: 2.3%, metastasis: 8.2%) were included. Deterministic tractography based on nTMS motor or language maps as seed regions was performed with 25%, 50%, and 75% of the individual fractional anisotropy threshold (FAT). Lesion-to-tract distances (LTDs) were measured between the tumor mass and the corticospinal tract (CST), arcuate fascicle (AF), or other closest language-related tracts. LTDs were compared between patients and correlated to the functional status (no/transient/permanent surgery-related paresis or aphasia). Significant differences were found between patients with no or transient surgery-related deficits and patients with permanent surgery-related deficits regarding LTDs in relation to the CST (p < 0.0001), AF (p ≤ 0.0491), or other closest language-related tracts (p ≤ 0.0435). The cut-off values for surgery-related paresis or aphasia were ≤12 mm (LTD—CST) and ≤16 mm (LTD—AF) or ≤25 mm (LTD—other closest language-related tract), respectively. Moreover, there were significant associations between the status of surgery-related deficits and the LTD when considering the CST (range r: −0.3994 to −0.3910, p < 0.0001) or AF (range r: −0.2918 to −0.2592, p = 0.0135 and p = 0.0473 for 25% and 50% FAT). In conclusion, this is the largest study evaluating the application of both preoperative functional mapping and function-based tractography for motor and language function for risk stratification in patients with functionally eloquent tumors. The LTD may qualify as a viable marker that can be seamlessly assessed in the clinical neurooncological setup.
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Affiliation(s)
- Nico Sollmann
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany; (N.S.); (H.Z.); (A.F.); (N.W.); (S.I.); (A.S.); (B.M.)
- TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, 81675 Munich, Germany
- Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany;
| | - Haosu Zhang
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany; (N.S.); (H.Z.); (A.F.); (N.W.); (S.I.); (A.S.); (B.M.)
| | - Alessia Fratini
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany; (N.S.); (H.Z.); (A.F.); (N.W.); (S.I.); (A.S.); (B.M.)
| | - Noémie Wildschuetz
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany; (N.S.); (H.Z.); (A.F.); (N.W.); (S.I.); (A.S.); (B.M.)
| | - Sebastian Ille
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany; (N.S.); (H.Z.); (A.F.); (N.W.); (S.I.); (A.S.); (B.M.)
| | - Axel Schröder
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany; (N.S.); (H.Z.); (A.F.); (N.W.); (S.I.); (A.S.); (B.M.)
| | - Claus Zimmer
- Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany;
| | - Bernhard Meyer
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany; (N.S.); (H.Z.); (A.F.); (N.W.); (S.I.); (A.S.); (B.M.)
| | - Sandro M. Krieg
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany; (N.S.); (H.Z.); (A.F.); (N.W.); (S.I.); (A.S.); (B.M.)
- TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, 81675 Munich, Germany
- Correspondence:
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Wende T, Hoffmann KT, Meixensberger J. Tractography in Neurosurgery: A Systematic Review of Current Applications. J Neurol Surg A Cent Eur Neurosurg 2020; 81:442-455. [PMID: 32176926 DOI: 10.1055/s-0039-1691823] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The ability to visualize the brain's fiber connections noninvasively in vivo is relatively young compared with other possibilities of functional magnetic resonance imaging. Although many studies showed tractography to be of promising value for neurosurgical care, the implications remain inconclusive. An overview of current applications is presented in this systematic review. A search was conducted for (("tractography" or "fiber tracking" or "fibre tracking") and "neurosurgery") that produced 751 results. We identified 260 relevant articles and added 20 more from other sources. Most publications concerned surgical planning for resection of tumors (n = 193) and vascular lesions (n = 15). Preoperative use of transcranial magnetic stimulation was discussed in 22 of these articles. Tractography in skull base surgery presents a special challenge (n = 29). Fewer publications evaluated traumatic brain injury (TBI) (n = 25) and spontaneous intracranial bleeding (n = 22). Twenty-three articles focused on tractography in pediatric neurosurgery. Most authors found tractography to be a valuable addition in neurosurgical care. The accuracy of the technique has increased over time. There are articles suggesting that tractography improves patient outcome after tumor resection. However, no reliable biomarkers have yet been described. The better rehabilitation potential after TBI and spontaneous intracranial bleeding compared with brain tumors offers an insight into the process of neurorehabilitation. Tractography and diffusion measurements in some studies showed a correlation with patient outcome that might help uncover the neuroanatomical principles of rehabilitation itself. Alternative corticofugal and cortico-cortical networks have been implicated in motor recovery after ischemic stroke, suggesting more complex mechanisms in neurorehabilitation that go beyond current models. Hence tractography may potentially be able to predict clinical deficits and rehabilitation potential, as well as finding possible explanations for neurologic disorders in retrospect. However, large variations of the results indicate a lack of data to establish robust diagnostical concepts at this point. Therefore, in vivo tractography should still be interpreted with caution and by experienced surgeons.
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Affiliation(s)
- Tim Wende
- Department of Neurosurgery, University Hospital Leipzig, Leipzig, Germany
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Islam M, Cooray G, Benmakhlouf H, Hatiboglu M, Sinclair G. Integrating navigated transcranial magnetic stimulation motor mapping in hypofractionated and single-dose gamma knife radiosurgery: A two-patient case series and a review of literature. Surg Neurol Int 2020; 11:29. [PMID: 32257555 PMCID: PMC7110065 DOI: 10.25259/sni_406_2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 11/11/2019] [Indexed: 02/07/2023] Open
Abstract
Background: The aim of the study was to demonstrate the feasibility of integrating navigated transcranial magnetic stimulation (nTMS) in preoperative gamma knife radiosurgery (GKRS) planning of motor eloquent brain tumors. Case Description: The first case was a 53-year-old female patient with metastatic breast cancer who developed focal epileptic seizures and weakness of the left hand. The magnetic resonance imaging (MRI) scan demonstrated a 30 mm metastasis neighboring the right precentral gyrus and central sulcus. The lesion was treated with adaptive hypofractionated GKRS following preoperative nTMS-based motor mapping. Subsequent follow-up imaging (up to 12 months) revealed next to complete tumor ablation without toxicity. The second case involved a previously healthy 73-year-old male who similarly developed new left-handed weakness. A subsequent MRI demonstrated a 26 mm metastatic lesion, located in the right postcentral gyrus and 5 mm from the hand motor area. The extracranial screening revealed a likely primary lung adenocarcinoma. The patient underwent preoperative nTMS motor mapping prior to treatment. Perilesional edema was noted 6 months postradiosurgery; nevertheless, long- term tumor control was demonstrated. Both patients experienced motor function normalization shortly after treatment, continuing to final follow-up. Conclusion: Integrating preoperative nTMS motor mapping in treatment planning allowed us to reduce dose distributions to perilesional motor fibers while achieving salvage of motor function, lasting seizure freedom, and tumor control. These initial data along with our review of the available literature suggest that nTMS can be of significant assistance in brain radiosurgery. Prospective studies including larger number of patients are still warranted.
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Affiliation(s)
- Mominul Islam
- Clinical Neuroscience, Karolinska Institute, İstanbul, Turkey
| | - Gerald Cooray
- Clinical Neuroscience, Karolinska Institute, İstanbul, Turkey
| | - Hamza Benmakhlouf
- Department of Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, İstanbul, Turkey
| | - Mustafa Hatiboglu
- Department of Neurosurgery, Beykoz Institute of Life Science and Biotechnology, Bezmialem Vakif University, İstanbul, Turkey
| | - Georges Sinclair
- Department of Neurosurgery, Beykoz Institute of Life Science and Biotechnology, Bezmialem Vakif University, İstanbul, Turkey.,Department of Oncology, Royal Berkshire NHS Foundation Trust, Reading, Berkshire.,Department of Neurosurgery, Karolinska University Hospital, Stockholm, Sweden
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Yang X, Zhang K. Navigated transcranial magnetic stimulation brain mapping: Achievements, opportunities, and prospects. GLIOMA 2020. [DOI: 10.4103/glioma.glioma_13_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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23
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Raffa G, Quattropani MC, Germanò A. When imaging meets neurophysiology: the value of navigated transcranial magnetic stimulation for preoperative neurophysiological mapping prior to brain tumor surgery. Neurosurg Focus 2019; 47:E10. [DOI: 10.3171/2019.9.focus19640] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 09/04/2019] [Indexed: 11/06/2022]
Abstract
Maximal safe resection is the modern goal for surgery of intrinsic brain tumors located in or close to brain eloquent areas. Nowadays different neuroimaging techniques provide important anatomical and functional information regarding the brain functional organization that can be used to plan a customized surgical strategy to preserve functional networks, and to increase the extent of tumor resection. Among these techniques, navigated transcranial magnetic stimulation (nTMS) has recently gained great favor among the neurosurgical community for preoperative mapping and planning prior to brain tumor surgery. It represents an advanced neuroimaging technique based on the neurophysiological mapping of the functional cortical brain organization. Moreover, it can be combined with other neuroimaging techniques such as diffusion tensor imaging tractography, thus providing a reliable reconstruction of brain eloquent networks. Consequently, nTMS mapping may provide reliable noninvasive brain functional mapping, anticipating information that otherwise may be available to neurosurgeons only in the operating theater by using direct electrical stimulation. The authors describe the reliability and usefulness of the preoperative nTMS-based approach in neurosurgical practice, and briefly discuss their experience using nTMS as well as currently available evidence in the literature supporting its clinical use. In particular, special attention is reserved for the discussion of the role of nTMS as a novel tool for the preoperative neurophysiological mapping of motor and language networks prior to surgery of intrinsic brain tumors located in or close to eloquent networks, as well as for future and promising applications of nTMS in neurosurgical practice.
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Affiliation(s)
- Giovanni Raffa
- 1Division of Neurosurgery, BIOMORF Department, University of Messina, Italy; and
| | | | - Antonino Germanò
- 1Division of Neurosurgery, BIOMORF Department, University of Messina, Italy; and
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24
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Fekonja L, Wang Z, Bährend I, Rosenstock T, Rösler J, Wallmeroth L, Vajkoczy P, Picht T. Manual for clinical language tractography. Acta Neurochir (Wien) 2019; 161:1125-1137. [PMID: 31004240 PMCID: PMC6525736 DOI: 10.1007/s00701-019-03899-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 03/28/2019] [Indexed: 11/30/2022]
Abstract
Background We introduce a user-friendly, standardized protocol for tractography of the major language fiber bundles. Method The introduced method uses dMRI images for tractography whereas the ROI definition is based on structural T1 MPRAGE MRI templates, without normalization to MNI space. ROIs for five language-relevant fiber bundles were visualized on an axial, coronal, or sagittal view of T1 MPRAGE images. The ROIs were defined based upon the tracts’ obligatory pathways, derived from literature and own experiences in peritumoral tractography. Results The resulting guideline was evaluated for each fiber bundle in ten healthy subjects and ten patients by one expert and three raters. Overall, 300 ROIs were evaluated and compared. The targeted language fiber bundles could be tracked in 88% of the ROI pairs, based on the raters’ result blinded ROI placements. The evaluation indicated that the precision of the ROIs did not relate to the varying experience of the raters. Conclusions Our guideline introduces a standardized language tractography method for routine preoperative workup and for research contexts. The ROI placement guideline based on easy-to-identify anatomical landmarks proved to be user-friendly and accurate, also in inexperienced test persons.
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Affiliation(s)
- Lucius Fekonja
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany.
- Cluster of Excellence: "Matters of Activity. Image Space Material", Humboldt University, Berlin, Germany.
| | - Ziqian Wang
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Ina Bährend
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Tizian Rosenstock
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Judith Rösler
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Lara Wallmeroth
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Peter Vajkoczy
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Thomas Picht
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
- Cluster of Excellence: "Matters of Activity. Image Space Material", Humboldt University, Berlin, Germany
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25
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Costabile JD, Alaswad E, D'Souza S, Thompson JA, Ormond DR. Current Applications of Diffusion Tensor Imaging and Tractography in Intracranial Tumor Resection. Front Oncol 2019; 9:426. [PMID: 31192130 PMCID: PMC6549594 DOI: 10.3389/fonc.2019.00426] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 05/07/2019] [Indexed: 01/01/2023] Open
Abstract
In the treatment of brain tumors, surgical intervention remains a common and effective therapeutic option. Recent advances in neuroimaging have provided neurosurgeons with new tools to overcome the challenge of differentiating healthy tissue from tumor-infiltrated tissue, with the aim of increasing the likelihood of maximizing the extent of resection volume while minimizing injury to functionally important regions. Novel applications of diffusion tensor imaging (DTI), and DTI-derived tractography (DDT) have demonstrated that preoperative, non-invasive mapping of eloquent cortical regions and functionally relevant white matter tracts (WMT) is critical during surgical planning to reduce postoperative deficits, which can decrease quality of life and overall survival. In this review, we summarize the latest developments of applying DTI and tractography in the context of resective surgery and highlight its utility within each stage of the neurosurgical workflow: preoperative planning and intraoperative management to improve postoperative outcomes.
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Affiliation(s)
- Jamie D Costabile
- Department of Neurosurgery, School of Medicine, University of Colorado, Aurora, CO, United States
| | - Elsa Alaswad
- Department of Neurosurgery, School of Medicine, University of Colorado, Aurora, CO, United States
| | - Shawn D'Souza
- Department of Neurosurgery, School of Medicine, University of Colorado, Aurora, CO, United States
| | - John A Thompson
- Department of Neurosurgery, School of Medicine, University of Colorado, Aurora, CO, United States
| | - D Ryan Ormond
- Department of Neurosurgery, School of Medicine, University of Colorado, Aurora, CO, United States
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26
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Sollmann N, Zhang H, Schramm S, Ille S, Negwer C, Kreiser K, Meyer B, Krieg SM. Function-specific Tractography of Language Pathways Based on nTMS Mapping in Patients with Supratentorial Lesions. Clin Neuroradiol 2018; 30:123-135. [PMID: 30519814 DOI: 10.1007/s00062-018-0749-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 11/22/2018] [Indexed: 10/27/2022]
Abstract
PURPOSE In patients with supratentorial lesions diffusion tensor imaging fiber tracking (DTI-FT) is increasingly used to visualize subcortical fiber courses. Navigated transcranial magnetic stimulation (nTMS) was applied in this study to reveal specific cortical functions by investigating the particular language errors elicited by stimulation. To make DTI-FT more function-specific, the identified language-positive nTMS spots were used as regions of interest (ROIs). METHODS In this study 40 patients (mean age 53.8 ± 16.0 years) harboring language-eloquent left hemispheric lesions underwent preoperative nTMS language mapping. All induced error categories were separately defined as a ROI and used for function-specific nTMS-based DTI-FT. The fractions of patients showing various subcortical language-related pathways and the fibers-per-tract ratio (number of visualized fibers divided by the number of visualized tracts) were evaluated and compared for tractography with the single error types against less specific tractography including all identified cortical language sites (all errors except hesitations). RESULTS The nTMS-based DTI-FT using all errors except hesitations led to high fractions of visualized tracts (81.1% of patients), with a fibers-per-tract ratio of 538.4 ± 340.5. When only using performance errors, a predominant visualization of the superior longitudinal fascicle (SLF) occurred, which is known to be involved in articulatory processes. Fibers-per-tract ratios were comparatively stable for all single error categories when compared to all errors except hesitations (p > 0.05). CONCLUSION This is one of the first studies aiming on function-specific tractography. The results demonstrated that when using different error categories as ROIs, more detailed nTMS-based DTI-FT and, therefore, potentially superior intraoperative guidance becomes possible.
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Affiliation(s)
- Nico Sollmann
- Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.,Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.,TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Haosu Zhang
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany
| | - Severin Schramm
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany
| | - Sebastian Ille
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.,TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Chiara Negwer
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany
| | - Kornelia Kreiser
- Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany
| | - Bernhard Meyer
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany
| | - Sandro M Krieg
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany. .,TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
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27
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Conti Nibali M, Rossi M, Sciortino T, Riva M, Gay LG, Pessina F, Bello L. Preoperative surgical planning of glioma: limitations and reliability of fMRI and DTI tractography. J Neurosurg Sci 2018; 63:127-134. [PMID: 30290696 DOI: 10.23736/s0390-5616.18.04597-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Brain mapping techniques (intraoperative neurophysiology and neuropsychology) represent the gold standard in glioma surgery, and particularly in glioma resection. Since the introduction of MRI in the clinical practice, several advanced applications have been developed, like functional MRI (fMRI) and diffusion imaging-based tractography (DTI), which both have an application in glioma surgery. fMRI allows to identify cortical areas related to a specific function, DTI allows to reconstruct a model of the sub-cortical connectivity. This paper describes the clinical application of fMRI and DTI, enlightening sensitivity and specificity in comparison to gold standard and underlining their limitations in surgical decision making.
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Affiliation(s)
- Marco Conti Nibali
- Unit of Neurosurgical Oncology, Department of Oncology and Hemato-Oncology, Humanitas Research Hospital, IRCCS, University of Milan, Milan, Italy -
| | - Marco Rossi
- Unit of Neurosurgical Oncology, Department of Oncology and Hemato-Oncology, Humanitas Research Hospital, IRCCS, University of Milan, Milan, Italy
| | - Tommaso Sciortino
- Unit of Neurosurgical Oncology, Department of Oncology and Hemato-Oncology, Humanitas Research Hospital, IRCCS, University of Milan, Milan, Italy
| | - Marco Riva
- Unit of Neurosurgical Oncology, Department of Oncology and Hemato-Oncology, Humanitas Research Hospital, IRCCS, University of Milan, Milan, Italy.,Department of Medical Biotechnology and Translational Medicine, Humanitas Research Hospital, IRCCS, University of Milan, Milan, Italy
| | - Lorenzo G Gay
- Unit of Neurosurgical Oncology, Department of Oncology and Hemato-Oncology, Humanitas Research Hospital, IRCCS, University of Milan, Milan, Italy
| | - Federico Pessina
- Unit of Neurosurgical Oncology, Department of Oncology and Hemato-Oncology, Humanitas Research Hospital, IRCCS, University of Milan, Milan, Italy.,Department of Biomedical Sciences, Humanitas University, Milan, Italy
| | - Lorenzo Bello
- Unit of Neurosurgical Oncology, Department of Oncology and Hemato-Oncology, Humanitas Research Hospital, IRCCS, University of Milan, Milan, Italy
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Abstract
Focal epilepsy originating from the insular cortex is rare. One reason is the small amount of cortical tissue compared with other lobes of the brain. However, the incidence of insular epilepsy might be underestimated because of diagnostic difficulties. The semiology and the surface EEG are often not meaningful or even misleading, and elaborated imaging might be necessary. The close connections of the insular cortex with other potentially epileptogenic areas, such as the temporal lobe or frontal/central cortex, is increasingly recognized as possible reason for failure of epilepsy surgery for temporal or extratemporal seizures. Therefore, some centers consider invasive EEG recording of the insular cortex not only in case of insular epilepsy but also in other focal epilepsies with nonconclusive results from the presurgical work-up. The surgical approach to and resection of insular cortex is challenging because of its deep location and proximity to highly eloquent brain structures. Over the last decades, technical adjuncts like navigation tools, electrophysiological monitoring and intraoperative imaging have improved the outcome after surgery. Nevertheless, there is still a considerable rate of postoperative transient or permanent deficits, in some cases as unavoidable and calculated deficits. In most of the recent series, seizure outcome was favorable and comparable with extratemporal epilepsy surgery or even better. Up to now, the data volume concerning long-term follow-up is limited. This review focusses on the surgical challenges of resections to treat insular epilepsy, on prognostic factors concerning seizure outcome, on postoperative deficits and complications. Moreover, less invasive surgical techniques to treat epilepsy in this highly eloquent area are summarized.
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Surgery of language-eloquent tumors in patients not eligible for awake surgery: the impact of a protocol based on navigated transcranial magnetic stimulation on presurgical planning and language outcome, with evidence of tumor-induced intra-hemispheric plasticity. Clin Neurol Neurosurg 2018; 168:127-139. [PMID: 29549813 DOI: 10.1016/j.clineuro.2018.03.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 02/28/2018] [Accepted: 03/06/2018] [Indexed: 01/06/2023]
Abstract
OBJECTIVES Awake surgery and intraoperative monitoring represent the gold standard for surgery of brain tumors located in the perisylvian region of the dominant hemisphere due to their ability to map and preserve the language network during surgery. Nevertheless, in some cases awake surgery is not feasible. This could increase the risk of postoperative language deficit. Navigated transcranial magnetic stimulation (nTMS) and nTMS-based DTI fiber tracking (DTI-FT) provide a preoperative mapping and reconstruction of the cortico-subcortical language network. This can be used to plan and guide the surgical strategy to preserve the language function. The objective if this study is to describe the impact of a non-invasive preoperative protocol for mapping the language network through the nTMS and nTMS-based DTI-FT in patients not eligible for awake surgery and thereby operated under general anesthesia for suspected language-eloquent brain tumors. PATIENTS AND METHODS We reviewed clinical data of patients not eligible for awake surgery and operated under general anaesthesia between 2015 and 2016. All patients underwent nTMS language cortical mapping and nTMS-based DTI-FT of subcortical language fascicles. The nTMS findings were used to plan and guide the maximal safe resection of the tumor. The impact on postoperative language outcome and the accuracy of the nTMS-based mapping in predicting language deficits were evaluated. RESULTS Twenty patients were enrolled in the study. The nTMS-based reconstruction of the language network was successful in all patients. Interestingly, we observed a significant association between tumor localization and the cortical distribution of the nTMS errors (p = 0.004), thereby suggesting an intra-hemispheric plasticity of language cortical areas, probably induced by the tumor itself. The nTMS mapping disclosed the true-eloquence of lesions in 12 (60%) of all suspected cases. In the remaining 8 cases (40%) the suspected eloquence of the lesion was disproved. The nTMS-based findings guided the planning and surgery through the visual feedback of navigation. This resulted in a slight reduction of the postoperative language performance at discharge that was completely recovered after one month from surgery. The accuracy of the nTMS-based protocol in predicting postoperative permanent deficits was significantly high, especially for false-eloquent lesions (p = 0.04; sensitivity 100%, specificity 57.14%, negative predictive value 100%, positive predicitive value 50%). CONCLUSIONS The nTMS-based preoperative mapping allows for a reliable visualization of the language network, being also able to identify an intra-hemispheric tumor-induced cortical plasticity. It allows for a customized surgical strategy that could preserve post-operative language function. This approach should be considered as a support for neurosurgeons whenever approaching patients affected by suspected language-eloquent tumors but not eligible for awake surgery.
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Preoperative Navigated Transcranial Magnetic Stimulation and Tractography to Guide Endoscopic Cystoventriculostomy: A Technical Note and Case Report. World Neurosurg 2018; 109:209-217. [DOI: 10.1016/j.wneu.2017.09.185] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 09/25/2017] [Accepted: 09/26/2017] [Indexed: 11/21/2022]
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Rosenstock T, Giampiccolo D, Schneider H, Runge SJ, Bährend I, Vajkoczy P, Picht T. Specific DTI seeding and diffusivity-analysis improve the quality and prognostic value of TMS-based deterministic DTI of the pyramidal tract. NEUROIMAGE-CLINICAL 2017; 16:276-285. [PMID: 28840099 PMCID: PMC5560117 DOI: 10.1016/j.nicl.2017.08.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 06/22/2017] [Accepted: 08/11/2017] [Indexed: 12/17/2022]
Abstract
Object Navigated transcranial magnetic stimulation (nTMS) combined with diffusion tensor imaging (DTI) is used preoperatively in patients with eloquent-located brain lesions and allows analyzing non-invasively the spatial relationship between the tumor and functional areas (e.g. the motor cortex and the corticospinal tract [CST]). In this study, we examined the diffusion parameters FA (fractional anisotropy) and ADC (apparent diffusion coefficient) within the CST in different locations and analyzed their interrater reliability and usefulness for predicting the patients' motor outcome with a precise approach of specific region of interest (ROI) seeding based on the color-coded FA-map. Methods Prospectively collected data of 30 patients undergoing bihemispheric nTMS mapping followed by nTMS-based DTI fiber tracking prior to surgery of motor eloquent high-grade gliomas were analyzed by 2 experienced and 1 unexperienced examiner. The following data were scrutinized for both hemispheres after tractography based on nTMS-motor positive cortical seeds and a 2nd region of interest in one layer of the caudal pons defined by the color-coded FA-map: the pre- and postoperative motor status (day of discharge und 3 months), the closest distance between the tracts and the tumor (TTD), the fractional anisotropy (FA) and the apparent diffusion coefficient (ADC). The latter as an average within the CST as well as specific values in different locations (peritumoral, mesencephal, pontine). Results Lower average FA-values within the affected CST as well as higher average ADC-values are significantly associated with deteriorated postoperative motor function (p = 0.006 and p = 0.026 respectively). Segmental analysis within the CST revealed that the diffusion parameters are especially disturbed on a peritumoral level and that the degree of their impairment correlates with motor deficits (FA p = 0.065, ADC p = 0.007). No significant segmental variation was seen in the healthy hemisphere. The interrater reliability showed perfect agreement for almost all analyzed parameters. Conclusions Adding diffusion weighted imaging derived information on the structural integrity of the nTMS-based tractography results improves the predictive power for postoperative motor outcome. Utilizing a second subcortical ROI which is specifically seeded based on the color-coded FA map increases the tracking quality of the CST independently of the examiner's experience. Further prospective studies are needed to validate the nTMS-based prediction of the patient's outcome. ROI seeding based on nTMS-data and FA-maps improves DTI tractography of the CST. Perfect interrater reliability for DTI tractography of the CST was observed. The pattern of diffusivity disturbance predicts the postoperative motor outcome.
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Affiliation(s)
- Tizian Rosenstock
- Department of Neurosurgery, Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany
| | - Davide Giampiccolo
- Institute of Neurosurgery, University Hospital, Piazzale Stefani 1, 37100 Verona, Italy
| | - Heike Schneider
- Department of Neurosurgery, Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany
| | - Sophia Jutta Runge
- Department of Neurosurgery, Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany
| | - Ina Bährend
- Department of Neurosurgery, Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany
| | - Peter Vajkoczy
- Department of Neurosurgery, Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany
| | - Thomas Picht
- Department of Neurosurgery, Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany
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Sollmann N, Meyer B, Krieg SM. Implementing Functional Preoperative Mapping in the Clinical Routine of a Neurosurgical Department: Technical Note. World Neurosurg 2017; 103:94-105. [PMID: 28377253 DOI: 10.1016/j.wneu.2017.03.114] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 03/22/2017] [Accepted: 03/23/2017] [Indexed: 01/01/2023]
Abstract
BACKGROUND Navigated transcranial magnetic stimulation (nTMS) is increasingly being used for mapping of various brain functions and in nTMS-based tractography in neurosurgical departments worldwide. When a department begins using nTMS data in the clinical workflow, smooth integration into the hospital's existing infrastructure is mandatory. Standardized approaches for this beyond the mapping or tractography procedures themselves have not yet been described. METHODS To create an effective workflow for neurosurgical nTMS mapping, we present the findings of our 7 years of experience and progressive integration into the clinical routine. RESULTS After indication for mapping is made, the workflow starts with patient admission and includes all preoperative steps until tumor resection. Importantly, only standard software and devices were used, enabling new centers to easily integrate data derived from nTMS mapping and nTMS-based tractography into their hospital's infrastructure. Registration of the patient, appointment planning, and documentation of results of the nTMS procedures within the hospital information system (HIS) can be achieved by a novel tailored software mask. As another important part of the workflow, nTMS data are imported into the picture archiving and communication system (PACS) via PACS integrator software. In addition, for surgical planning including nTMS-based tractography, nTMS data can be effectively included in surgical neuronavigation software. CONCLUSIONS Optimized integration of nTMS data can be achieved using a standardized workflow. The seamless integration and availability of nTMS data are crucial to the acceptance of these data in the clinical routine. This optimized workflow can serve as a guide for centers beginning to use nTMS data in patient care.
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Affiliation(s)
- Nico Sollmann
- Department of Neurosurgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Bernhard Meyer
- Department of Neurosurgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Sandro M Krieg
- Department of Neurosurgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.
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