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Hartmann K, Stein KP, Neyazi B, Sandalcioglu IE. Theranostic applications of optical coherence tomography in neurosurgery? Neurosurg Rev 2021; 45:421-427. [PMID: 34398385 PMCID: PMC8827310 DOI: 10.1007/s10143-021-01599-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 03/11/2021] [Accepted: 06/27/2021] [Indexed: 12/14/2022]
Abstract
In light of our own experiences, we value the existing literature to critically point out possible “near” future applications of optical coherence tomography (OCT) as an intraoperative neurosurgical guidance tool. “Pub Med”, “Cochrane Library”, “Crossref Metadata Search”, and “IEEE Xplore” databases as well as the search engine “Google Scholar” were screened for “optical coherence tomography + neurosurgery”, “optical coherence tomography + intraoperative imaging + neurosurgery”, and “microscope integrated optical coherence tomography + neurosurgery”. n = 51 articles related to the use of OCT as an imaging technique in the field of neurosurgery or neurosurgical research. n = 7 articles documented the intraoperative use of OCT in patients. n = 4 articles documented the use of microscope-integrated optical coherence tomography as a neurosurgical guidance tool. The Results demonstrate that OCT is the first imaging technique to study microanatomy in vivo. Postoperative analysis of intraoperative scans holds promise to enrich our physiological and pathophysiological understanding of the human brain. No data exists to prove that OCT-guided surgery minimizes perioperative morbidity or extends tumor resection. But results suggest that regular use of microscope-integrated OCT could increase security during certain critical microsurgical steps like, e.g., dural dissection at cavernous sinus, transtentorial approaches, or aneurysm clip placement. Endoscopy integration could aid surgery in regions which are not yet accessible to real-time imaging modalities like the ventricles or hypophysis. Theranostic instruments which combine OCT with laser ablation might gain importance in the emerging field of minimal invasive tumor surgery. OCT depicts vessel wall layers and its pathologies uniquely. Doppler OCT could further visualize blood flow in parallel. These abilities shed light on promising future applications in the field of vascular neurosurgery.
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Affiliation(s)
- Karl Hartmann
- Universitätsklinik Für Neurochirurgie, Otto-Von-Guericke-Universität Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Deutschland.
| | - Klaus-Peter Stein
- Universitätsklinik Für Neurochirurgie, Otto-Von-Guericke-Universität Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Deutschland
| | - Belal Neyazi
- Universitätsklinik Für Neurochirurgie, Otto-Von-Guericke-Universität Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Deutschland
| | - I Erol Sandalcioglu
- Universitätsklinik Für Neurochirurgie, Otto-Von-Guericke-Universität Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Deutschland
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2
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Valdés PA, Roberts DW, Lu FK, Golby A. Optical technologies for intraoperative neurosurgical guidance. Neurosurg Focus 2016; 40:E8. [PMID: 26926066 DOI: 10.3171/2015.12.focus15550] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Biomedical optics is a broadly interdisciplinary field at the interface of optical engineering, biophysics, computer science, medicine, biology, and chemistry, helping us understand light-tissue interactions to create applications with diagnostic and therapeutic value in medicine. Implementation of biomedical optics tools and principles has had a notable scientific and clinical resurgence in recent years in the neurosurgical community. This is in great part due to work in fluorescence-guided surgery of brain tumors leading to reports of significant improvement in maximizing the rates of gross-total resection. Multiple additional optical technologies have been implemented clinically, including diffuse reflectance spectroscopy and imaging, optical coherence tomography, Raman spectroscopy and imaging, and advanced quantitative methods, including quantitative fluorescence and lifetime imaging. Here we present a clinically relevant and technologically informed overview and discussion of some of the major clinical implementations of optical technologies as intraoperative guidance tools in neurosurgery.
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Affiliation(s)
- Pablo A Valdés
- Departments of 1 Neurosurgery and.,Department of Neurosurgery, Harvard Medical School, Boston Children's Hospital, Boston
| | - David W Roberts
- Section of Neurosurgery, Geisel School of Medicine at Dartmouth, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire
| | | | - Alexandra Golby
- Departments of 1 Neurosurgery and.,Radiology, and.,Dana Farber Cancer Institute, Harvard Medical School, Brigham and Women's Hospital
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3
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Hillary FG, Rajtmajer SM, Roman CA, Medaglia JD, Slocomb-Dluzen JE, Calhoun VD, Good DC, Wylie GR. The rich get richer: brain injury elicits hyperconnectivity in core subnetworks. PLoS One 2014; 9:e104021. [PMID: 25121760 PMCID: PMC4133194 DOI: 10.1371/journal.pone.0104021] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Accepted: 07/09/2014] [Indexed: 11/22/2022] Open
Abstract
There remains much unknown about how large-scale neural networks accommodate neurological disruption, such as moderate and severe traumatic brain injury (TBI). A primary goal in this study was to examine the alterations in network topology occurring during the first year of recovery following TBI. To do so we examined 21 individuals with moderate and severe TBI at 3 and 6 months after resolution of posttraumatic amnesia and 15 age- and education-matched healthy adults using functional MRI and graph theoretical analyses. There were two central hypotheses in this study: 1) physical disruption results in increased functional connectivity, or hyperconnectivity, and 2) hyperconnectivity occurs in regions typically observed to be the most highly connected cortical hubs, or the "rich club". The current findings generally support the hyperconnectivity hypothesis showing that during the first year of recovery after TBI, neural networks show increased connectivity, and this change is disproportionately represented in brain regions belonging to the brain's core subnetworks. The selective increases in connectivity observed here are consistent with the preferential attachment model underlying scale-free network development. This study is the largest of its kind and provides the unique opportunity to examine how neural systems adapt to significant neurological disruption during the first year after injury.
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Affiliation(s)
- Frank G. Hillary
- The Pennsylvania State University, Department of Psychology, University Park, Pennsylvania, United States of America
| | - Sarah M. Rajtmajer
- The Pennsylvania State University, Department of Mathematics, University Park, Pennsylvania, United States of America
| | - Cristina A. Roman
- The Pennsylvania State University, Department of Psychology, University Park, Pennsylvania, United States of America
| | - John D. Medaglia
- The Pennsylvania State University, Department of Psychology, University Park, Pennsylvania, United States of America
| | - Julia E. Slocomb-Dluzen
- Hershey Medical Center, Department of Neurology, Hershey, Pennsylvania, United States of America
| | - Vincent D. Calhoun
- The Mind Research Network, Albuquerque, New Mexico, United States of America
| | - David C. Good
- Hershey Medical Center, Department of Neurology, Hershey, Pennsylvania, United States of America
| | - Glenn R. Wylie
- Kessler Foundation Research Center, West Orange, New Jersey, United States of America
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4
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Wang Y, Sørensen MG, Zheng Q, Zhang C, Karsdal MA, Henriksen K. Will posttranslational modifications of brain proteins provide novel serological markers for dementias? Int J Alzheimers Dis 2012; 2012:209409. [PMID: 22779024 PMCID: PMC3388459 DOI: 10.1155/2012/209409] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 04/26/2012] [Indexed: 11/23/2022] Open
Abstract
Drug development for dementias is significantly hampered by the lack of easily accessible biomarkers. Fluid biomarkers of dementias provide indications of disease stage, but have little prognostic value, cannot detect early pathological changes, and can only be measured in CSF (cerebrospinal fluid) which significantly limits their applicability. In contrast, imaging based biomarkers can provide indications of probability of disease progression, yet are limited in applicability due to cost, radiation and radio-tracers. These aspects highlight the need for other approaches to the development of biomarkers of dementia, which should focus on not only providing information about pathological changes, but also on being measured easily and reproducibly. For other diseases, focus on development of assays monitoring highly specific protease-generated cleavage fragments of proteins has provided assays, which in serum or plasma have the ability to predict early pathological changes. Proteolytic processing of brain proteins, such as tau, APP, and α-synuclein, is a key pathological event in dementias. Here, we speculate that aiming biomarker development for dementias at detecting small brain protein degradation fragments of generated by brain-derived proteases specifically in blood samples could lead to the development of novel markers of disease progression, stage and importantly of treatment efficacy.
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Affiliation(s)
- Y. Wang
- Department of Biomarker Development, Nordic Bioscience A/S, Beijing 102206, China
| | - M. G. Sørensen
- Neurodegenerative Diseases, Nordic Bioscience A/S, Herlev Hovedgade 207, 2730 Herlev, Denmark
| | - Q. Zheng
- Department of Biomarker Development, Nordic Bioscience A/S, Beijing 102206, China
| | - C. Zhang
- Neurodegenerative Diseases, Nordic Bioscience A/S, Herlev Hovedgade 207, 2730 Herlev, Denmark
| | - M. A. Karsdal
- Neurodegenerative Diseases, Nordic Bioscience A/S, Herlev Hovedgade 207, 2730 Herlev, Denmark
| | - K. Henriksen
- Neurodegenerative Diseases, Nordic Bioscience A/S, Herlev Hovedgade 207, 2730 Herlev, Denmark
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5
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Elias WJ, Zheng ZA, Domer P, Quigg M, Pouratian N. Validation of connectivity-based thalamic segmentation with direct electrophysiologic recordings from human sensory thalamus. Neuroimage 2011; 59:2025-34. [PMID: 22036683 DOI: 10.1016/j.neuroimage.2011.10.049] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 09/18/2011] [Accepted: 10/12/2011] [Indexed: 11/17/2022] Open
Abstract
Connectivity-based segmentation has been used to identify functional gray matter subregions that are not discernable on conventional magnetic resonance imaging. However, the accuracy and reliability of this technique has only been validated using indirect means. In order to provide direct electrophysiologic validation of connectivity-based thalamic segmentations within human subjects, we assess the correlation of atlas-based thalamic anatomy, connectivity-based thalamic maps, and somatosensory evoked thalamic potentials in two adults with medication-refractory epilepsy who were undergoing intracranial EEG monitoring with intrathalamic depth and subdural cortical strip electrodes. MRI with atlas-derived localization was used to delineate the anatomic boundaries of the ventral posterolateral (VPL) nucleus of the thalamus. Somatosensory evoked potentials with intrathalamic electrodes physiologically identified a discrete region of phase reversal in the ventrolateral thalamus. Finally, DTI was obtained so that probabilistic tractography and connectivity-based segmentation could be performed to correlate the region of thalamus linked to sensory areas of the cortex, namely the postcentral gyrus. We independently utilized these three different methods in a blinded fashion to localize the "sensory" thalamus, demonstrating a high-degree of reproducible correlation between electrophysiologic and connectivity-based maps of the thalamus. This study provides direct electrophysiologic validation of probabilistic tractography-based thalamic segmentation. Importantly, this study provides an electrophysiological basis for using connectivity-based segmentation to further study subcortical anatomy and physiology while also providing the clinical basis for targeting deep brain nuclei with therapeutic stimulation. Finally, these direct recordings from human thalamus confirm early inferences of a sensory thalamic component of the N18 waveform in somatosensory evoked potentials.
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Affiliation(s)
- W Jeffrey Elias
- Department of Neurosurgery, University of Virginia Health Sciences Center, Box 800212, Charlottesville, Virginia 22903, USA.
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6
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Prakash N, Uhlemann F, Sheth SA, Bookheimer S, Martin N, Toga AW. Current trends in intraoperative optical imaging for functional brain mapping and delineation of lesions of language cortex. Neuroimage 2009; 47 Suppl 2:T116-26. [PMID: 18786643 PMCID: PMC2782948 DOI: 10.1016/j.neuroimage.2008.07.066] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Revised: 07/19/2008] [Accepted: 07/30/2008] [Indexed: 10/21/2022] Open
Abstract
Resection of a cerebral arteriovenous malformation (AVM), epileptic focus, or glioma, ideally has a prerequisite of microscopic delineation of the lesion borders in relation to the normal gray and white matter that mediate critical functions. Currently, Wada testing and functional magnetic resonance imaging (fMRI) are used for preoperative mapping of critical function, whereas electrical stimulation mapping (ESM) is used for intraoperative mapping. For lesion delineation, MRI and positron emission tomography (PET) are used preoperatively, whereas microscopy and histological sectioning are used intraoperatively. However, for lesions near eloquent cortex, these imaging techniques may lack sufficient resolution to define the relationship between the lesion and language function, and thus not accurately determine which patients will benefit from neurosurgical resection of the lesion without iatrogenic aphasia. Optical techniques such as intraoperative optical imaging of intrinsic signals (iOIS) show great promise for the precise functional mapping of cortices, as well as delineation of the borders of AVMs, epileptic foci, and gliomas. Here we first review the physiology of neuroimaging, and then progress towards the validation and justification of using intraoperative optical techniques, especially in relation to neurosurgical planning of resection AVMs, epileptic foci, and gliomas near or in eloquent cortex. We conclude with a short description of potential novel intraoperative optical techniques.
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Affiliation(s)
- Neal Prakash
- University of California, Los Angeles, Laboratory of Neuro Imaging, Los Angeles, CA 90095, USA.
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7
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Vazquez AL, Cohen ER, Gulani V, Hernandez-Garcia L, Zheng Y, Lee GR, Kim SG, Grotberg JB, Noll DC. Vascular dynamics and BOLD fMRI: CBF level effects and analysis considerations. Neuroimage 2006; 32:1642-55. [PMID: 16860574 DOI: 10.1016/j.neuroimage.2006.04.195] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2005] [Revised: 04/10/2006] [Accepted: 04/11/2006] [Indexed: 11/23/2022] Open
Abstract
Changes in the cerebral blood flow (CBF) baseline produce significant changes to the hemodynamic response. This work shows that increases in the baseline blood flow level produce blood oxygenation-level dependent (BOLD) and blood flow responses that are slower and lower in amplitude, while decreases in the baseline blood flow level produce faster and higher amplitude hemodynamic responses. This effect was characterized using a vascular model of the hemodynamic response that separated arterial blood flow response from the venous blood volume response and linked the input stimulus to the vascular response. The model predicted the baseline blood flow level effects to be dominated by changes in the arterial vasculature. Specifically, it predicted changes in the arterial blood flow time constant and venous blood volume time constant parameters of +294% and -24%, respectively, for a 27% increase in the baseline blood flow. The vascular model performance was compared to an empirical model of the hemodynamic response. The vascular and empirical hemodynamic models captured most of the baseline blood flow level effects observed and can be used to correct for these effects in fMRI data. While the empirical hemodynamic model is easy to implement, it did not incorporate any explicit physiological information.
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Affiliation(s)
- Alberto L Vazquez
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109-2108, USA.
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8
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Mericle RA, Richter EO, Eskioglu E, Watkins C, Prokai L, Batich C, Santra S. Preoperative endovascular brain mapping for intraoperative volumetric image guidance: preliminary concept and feasibility in animal models. J Neurosurg 2006; 104:566-73. [PMID: 16619661 DOI: 10.3171/jns.2006.104.4.566] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
The authors describe a novel concept for brain mapping in which an endovascular approach is used, and they demonstrate its feasibility in animal models. The purpose of endovascular brain mapping is to delineate clearly the nonfunctional brain parenchyma when a craniotomy is performed for resection. The nonfunctional brain will be stained with sharp visual margins, differentiating it from the functional, nonstained brain. The authors list four essential criteria for developing an ideal endovascular mapping agent, and they describe seven potential approaches for accomplishing a successful endovascular brain map.
Methods
Four Sprague–Dawley rats and one New Zealand white rabbit were used to determine initial feasibility of the procedure. The animals were anesthetized, and the internal carotid artery was catheterized. Four potential brain mapping agents were infused into the right hemisphere of the five animals. Afterward, the brains were removed and each was analyzed both grossly and histologically.
Fluorescein and FD&C Green No. 3 provided good visual clarity and margins, but required blood–brain barrier (BBB) manipulation. Tantalum particles enabled avoidance of BBB manipulation, but provided inadequate visual clarity, probably because of their size. A Sudan black “cocktail” provided excellent clarity and margins despite remaining in the brain capillaries.
Conclusions
This is a novel application of the endovascular approach, and has broad potential for clinical neurosurgical brain mapping. The animal models in this study establish the feasibility of the procedure. However, further study is required to demonstrate safety, minimize toxicity, investigate stain durability, and improve the characteristics of potential mapping agents. The authors are planning to conduct future studies for identification of mapping agents that do not require BBB manipulation or vascular occlusion.
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Affiliation(s)
- Robert A Mericle
- Department of Neurological Surgery, University of Florida McKnight Brain Institute, Gainesville, Florida, USA.
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Nariai T, Sato K, Hirakawa K, Ohta Y, Tanaka Y, Ishiwata K, Ishii K, Kamino K, Ohno K. Imaging of somatotopic representation of sensory cortex with intrinsic optical signals as guides for brain tumor surgery. J Neurosurg 2005; 103:414-23. [PMID: 16235671 DOI: 10.3171/jns.2005.103.3.0414] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Intrinsic optical signals in response to somatosensory stimuli were intraoperatively recorded during brain tumor surgery. In the present study, the authors report on the use of this technique as an intraoperative guide for the safe resection of tumors adjacent to or within the sensorimotor cortex. METHODS In 14 patients with tumors adjacent to or within the sensorimotor cortex, intrinsic optical signals in response to somatosensory stimuli were recorded by illuminating the brain surface with Xe white light and imaging the reflected light passing through a bandpass filter (605 nm). Results were compared with intraoperative recordings of sensory evoked potentials in all 14 patients and with noninvasive mapping modalities such as magnetoencephalography and positron emission tomography in selected patients. In all but two patients, the somatosensory optical signals were recorded on the primary sensory cortex. Optical signals elicited by stimulation of the first and fifth digits and the three branches of the trigeminal nerve were recorded at different locations on the sensory strip. This somatotopic information was useful in determining the resection border in patients with glioma located in the sensorimotor cortex. CONCLUSIONS Optical imaging of intrinsic signals is a useful technique with superior spatial resolution for delineating the somatotopic representation of human primary sensory cortex. Furthermore, it can be used as an intraoperative monitoring tool to improve the safety and accuracy of resections of brain tumors adjacent to or within the sensorimotor cortex.
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Affiliation(s)
- Tadashi Nariai
- Department of Neurosurgery and Physiology, Tokyo Medical and Dental University, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
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Vincent DJ, Hurd MW. Bioinformatics and functional magnetic resonance imaging in clinical populations: practical aspects of data collection, analysis, interpretation, and management. Neurosurg Focus 2005; 19:E4. [PMID: 16241106 DOI: 10.3171/foc.2005.19.4.5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In this paper the authors review the issues associated with bioinformatics and functional magnetic resonance (fMR) imaging in the context of neurosurgery. They discuss the practical aspects of data collection, analysis, interpretation, and the management of large data sets, and they consider the challenges involved in the adoption of fMR imaging into clinical neurosurgical practice. Their goal is to provide neurosurgeons and other clinicians with a better understanding of some of the current issues associated with bioinformatics or neuroinformatics and fMR imaging. Thousands to tens of thousands of images are typically acquired during an fMR imaging session. It is essential to follow an activation task paradigm exactly to obtain an accurate representation of cortical activation. These images are then interactively postprocessed offline to produce an activation map, or in some cases a series of maps. The maps may then be viewed and interpreted in consultation with a neurosurgeon and/or other clinicians. After this consultation, long-term archiving of the processed fMR activation maps along with the standard structural MR images is a complex but necessary final step in this process. The fMR modality represents a valuable tool in the neurosurgical planning process that is still in the developmental stages for routine clinical use, but holds exceptional promise for patient care.
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Affiliation(s)
- Diana J Vincent
- Department of Radiology, Medical University of South Carolina, Charleston, South Carolina 29425, USA.
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Pirotte B, Voordecker P, Neugroschl C, Baleriaux D, Wikler D, Metens T, Denolin V, Joffroy A, Massager N, Brotchi J, Levivier M. Combination of Functional Magnetic Resonance Imaging-guided Neuronavigation and Intraoperative Cortical Brain Mapping Improves Targeting of Motor Cortex Stimulation in Neuropathic Pain. Oper Neurosurg (Hagerstown) 2005; 56:344-59; discussion 344-59. [PMID: 15794831 DOI: 10.1227/01.neu.0000144837.31665.29] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2004] [Accepted: 08/16/2004] [Indexed: 11/19/2022] Open
Abstract
Abstract
OBJECTIVE:
To evaluate, regardless of the clinical results, the contribution of combining functional magnetic resonance imaging (fMRI) with intraoperative cortical brain mapping (iCM) as functional targeting methods for epidural chronic motor cortex stimulation (MCS) in refractory neuropathic pain.
METHODS:
Eighteen neuropathic pain patients (central stroke in six; trigeminal neuropathy in six; syrinx or amputation in six) who underwent operations for epidural MCS were studied with preoperative fMRI and iCM. fMRI investigated motor tasks of hands (as well as foot and tongue, when painful). fMRI data were analyzed with Statistical Parametric Mapping99 software (University College London, London, England; initial analysis threshold corresponding to P < 0.001), registered in a neuronavigation system, and correlated during surgery with iCM. The primary aim of this study was to improve the topographical precision of MCS. Matching of fMRI and iCM specifically was examined.
RESULTS:
Correspondence between the contour of the fMRI activation area and iCM in precentral gyrus (mean distance, 3.8 mm) was found in 17 (94%) of 18 patients. Eleven of them showed correspondence for more restrictive values of the analysis threshold (P < 0.0001); in six patients, the quality of the iCM was reduced by somatosensory wave attenuation and general anesthesia. In this group of six patients, a combination of both techniques was used for the final targeting. Correspondence was not found in one patient as the result of image distortion and residual motion artifact. At follow-up (4–60 mo), MCS induced significant pain relief in a total of 11 patients (61%).
CONCLUSION:
This study confirms the functional accuracy of fMRI guidance in neuropathic pain and illustrates the usefulness of combining fMRI guidance with iCM to improve the functional targeting in MCS. Because appropriate targeting is crucial to obtaining pain relief, this combination may increase the analgesic efficacy of MCS.
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Affiliation(s)
- Benoit Pirotte
- Department of Neurosurgery, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium.
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