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1 BOLD fMRI for Language Mapping Jay J. Pillai, M.D. Director of Functional MRI Associate Professor Neuroradiology Division The Russell H. Morgan Department.

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Presentation on theme: "1 BOLD fMRI for Language Mapping Jay J. Pillai, M.D. Director of Functional MRI Associate Professor Neuroradiology Division The Russell H. Morgan Department."— Presentation transcript:

1 1 BOLD fMRI for Language Mapping Jay J. Pillai, M.D. Director of Functional MRI Associate Professor Neuroradiology Division The Russell H. Morgan Department of Radiology and Radiological Science Johns Hopkins Univ. School of Medicine

2 Utility of BOLD Imaging for presurgical mapping Utility of BOLD Imaging for presurgical mapping Preoperative risk assessment Preoperative risk assessment –Language lateralization –Eloquent cortical localization Determine safest surgical trajectory Determine safest surgical trajectory Guide complementary intraoperative cortical mapping (ICS) Guide complementary intraoperative cortical mapping (ICS) Promote paradigm shift from positive to negative ICS mapping Promote paradigm shift from positive to negative ICS mapping –Smaller craniotomy, shorter mapping times & reduced morbidity 2

3 2 Giussani, Carlo; Roux, Frank-Emmanuel; MD, PhD; Ojemann, Jeffrey; Sganzerla, Erik; Pirillo, David; Papagno, Costanza Is Preoperative Functional Magnetic Resonance Imaging Reliable for Language Areas Mapping in Brain Tumor Surgery? Review of Language Functional Magnetic Resonance Imaging Neurosurgery. 66(1): , January BOLD validation: Studies comparing preop language fMRI to ICS (Localiz)— Giussani et al., Neurosurgery Jan 2010

4 4 Validation of fMRI: studies comparing fMRI to Wada [and in some cases ICS] results—Lang Lat & Localiz: FROM: Pillai JJ, Language fMRI IN Holodny AI (Ed), Functional Neuroimaging: A Clinical Approach, 2008, Informa Healthcare (New York, NY)

5 Complementary role of ICS and BOLD fMRI- --Why occasional discordance? 5 1) BOLD—positive activation, essential vs. participatory (mult tasks), NVU 2) ICS—negative activation 3) Covert vs. Overt tasks 4) Lack of standardization (OR ---neuropsych/lang---& BOLD) 5) Brain shift

6 6 Language Representation in the Brain: Classical Brodmann’s areas From Waxman SG. Correlative Neuroanatomy, 24 th Ed. Lange Medical Books/McGraw-Hill, New York, 2000.

7 7 Lubrano VLubrano V, Draper L, Roux FE.What makes surgical tumor resection feasible in Broca's area? Insights into intraoperative brain mapping. Neurosurgery May;66(5):868-75; discussion 875. Draper LRoux FE Lubrano VDraper LRoux FE  Study of 16 patients, with 29 language sites identified by positive stimulation, only 14 in classic Broca’s area  Localization varied by pathology: those w cavernomas or well-circumscribed tumors had 100% of sites within BA  Patients with gliomas—only 25% of sites corresponded to classical BA Lubrano et al., May 2010 issue of Neurosurgery

8 Landmark ICS study —value of ICS/negative mapping (Sanai et al., 2008 NEJM) 145 of 250 patients (58.0%) with at least one site with intraop stimulation- induced speech arrest, 82 patients w anomia, and 23 patients w alexia. 145 of 250 patients (58.0%) with at least one site with intraop stimulation- induced speech arrest, 82 patients w anomia, and 23 patients w alexia. Overall, 3094 of 3281 cortical sites (94.3%) were not associated with stimulation-induced language deficits. Overall, 3094 of 3281 cortical sites (94.3%) were not associated with stimulation-induced language deficits. 6 months after surgery, only 1.6% incidence of persistent language deficit. 6 months after surgery, only 1.6% incidence of persistent language deficit. Surprising variability in language localization/ICS reduces postop morbidity Surprising variability in language localization/ICS reduces postop morbidity 8

9 Glasser MF, Rilling JK. DTI Tractography of the Human Brain's Language Pathways. Cerebral Cortex 2008; 18(11): Performed a BOLD meta-analysis & overlaid activations onto results of group DTT(n=20)—STG & MTG seeding: Performed a BOLD meta-analysis & overlaid activations onto results of group DTT(n=20)—STG & MTG seeding: –phonemic, lexical/semantic & prosodic processing. 9

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11 New Dual Stream Model of Language--- validated by BOLD/DTT by Saur et al., 2008  Dorsal Stream- -sensorimotor mapping of sound to articulation/sublexical repetition of speech  STG to premotor cortices via the AF/SLF  Ventral Stream- --linguistic processing of sound to meaning/language comprehension  MTG to ventrolateral PFC via the extreme capsule 11

12 ISM validation of DTT/dual stream--Leclercq (2010) 10 patients with low-grade gliomas or dysplasia in language areas. 10 patients with low-grade gliomas or dysplasia in language areas. Compared DTT w intraop sc stim mapping (ISM) Compared DTT w intraop sc stim mapping (ISM) 17 (81%) of 21 positive stimulations concordant with DTT fiber bundles (within 6 mm) 17 (81%) of 21 positive stimulations concordant with DTT fiber bundles (within 6 mm) Stimulations of the AF ---articulatory and phonemic/syntactic dysfunction-- DS Stimulations of the AF ---articulatory and phonemic/syntactic dysfunction-- DS Stimulations of the IFOF ---semantic paraphasias--VS Stimulations of the IFOF ---semantic paraphasias--VS 12 Leclercq D, Duffau H, Delmaire C, Capelle L, Gatignol P, Ducros M, Chiras J, Lehéricy S. Comparison of diffusion tensor imaging tractography of language tracts and intraoperative subcortical stimulations..J Neurosurg Mar;112(3):

13 However, Some Limitations of BOLD Neurovascular Uncoupling Neurovascular Uncoupling Patient Task performance issues--training, monitoring, variable capabilities related to deficits Patient Task performance issues--training, monitoring, variable capabilities related to deficits Essential vs. Participatory (nonessential) function—role of convergent activation & complementary ICS Essential vs. Participatory (nonessential) function—role of convergent activation & complementary ICS Interpretation relies heavily on statistical thresholding Interpretation relies heavily on statistical thresholding Need for multiple tasks to assess entire language network Need for multiple tasks to assess entire language network 13

14 How do we address these limitations? 1) Do detailed QC analysis 1) Do detailed QC analysis 2) MRPor CVR mapping to eval risk of NVU 2) MRPor CVR mapping to eval risk of NVU 3) Use multiple tasks and assess convergence of activation (esp important in language—exp vs rec) 3) Use multiple tasks and assess convergence of activation (esp important in language—exp vs rec) 4) Use higher thresholds for motor and visual, but lower ones for language mapping 4) Use higher thresholds for motor and visual, but lower ones for language mapping 5) Rely on language tasks that are the best for lateralization 5) Rely on language tasks that are the best for lateralization 14

15 Neurovascular uncoupling--CVR maps & Perfusion MR BOLD CVR maps during breath-hold task or external CO2 challenge BOLD CVR maps during breath-hold task or external CO2 challenge MR perfusion (T2* DSC) can evaluate rCBV & rCBF elevations related to tumor angiogenesis MR perfusion (T2* DSC) can evaluate rCBV & rCBF elevations related to tumor angiogenesis Both approaches can evaluate risk for FN activ due to NVU Both approaches can evaluate risk for FN activ due to NVU 15


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