The Experts below are selected from a list of 198 Experts worldwide ranked by ideXlab platform

Meritxell Bach Cuadra - One of the best experts on this subject based on the ideXlab platform.

  • pretherapeutic motor thalamus resting state functional connectivity with visual areas predicts tremor arrest after thalamotomy for essential tremor tracing the cerebello thalamo visuo motor network
    World Neurosurgery, 2018
    Co-Authors: Constantin Tuleasca, Elena Najdenovska, Jean Regis, Tatiana Witjas, Nadine Girard, Jerome Champoudry, Mohamed Faouzi, Jeanphilippe Thiran, Meritxell Bach Cuadra
    Abstract:

    Background Essential tremor (ET) is a common movement disorder. Resting-state functional magnetic resonance imaging is a noninvasive Neuroimaging Method acquired in absence of task. Objective Our study aimed to correlate pretherapeutic ventrolateral thalamus functional connectivity (FC) with clinical results 1 year after stereotactic radiosurgical thalamotomy (SRS-T) for drug-resistant ET. Data from 12 healthy control individuals were additionally included. Methods Resting state was acquired for 17 consecutive (right-handed) patients, before and 1 year after left unilateral SRS-T. Standard tremor scores were evaluated pretherapeutically and 1 year after SRS-T. Tremor network was investigated using region of interest, left ventrolateral ventral (VLV) cluster, obtained from pretherapeutic diffusion magnetic resonance imaging. Seed-based FC was obtained as correlations between the time courses of the VLV and that of every other voxel. The seed-connectivity maps were obtained pretherapeutically and correlated across all patients with clinical outcome 1 year after SRS-T. One-year magnetic resonance signature volume was always located inside VLV and did not correlate with reported seed-FC measures (P > 0.05). Results We report statistically significant correlations between pretherapeutic VLV FC with clinical outcome for 1) right visual association area (Brodmann area, BA19) predicting 1 year activities of daily living decrease (Punc = 0.02); 2) left fusiform gyrus (BA37) predicting 1 year head tremor score improvement (Punc = 0.04); and 3) posterior cingulate (left BA23, Puncor = 0.009), lateral temporal cortex (right BA21, Punc = 0.02) predicting time to tremor arrest. Conclusions Our results suggest that pretherapeutic resting-state seed-FC of left VLV predicts tremor arrest after SRS-T for ET. Visual areas are identified as the main regions in this correlation.

Jeanphilippe Thiran - One of the best experts on this subject based on the ideXlab platform.

  • pretherapeutic motor thalamus resting state functional connectivity with visual areas predicts tremor arrest after thalamotomy for essential tremor tracing the cerebello thalamo visuo motor network
    World Neurosurgery, 2018
    Co-Authors: Constantin Tuleasca, Elena Najdenovska, Jean Regis, Tatiana Witjas, Nadine Girard, Jerome Champoudry, Mohamed Faouzi, Jeanphilippe Thiran, Meritxell Bach Cuadra
    Abstract:

    Background Essential tremor (ET) is a common movement disorder. Resting-state functional magnetic resonance imaging is a noninvasive Neuroimaging Method acquired in absence of task. Objective Our study aimed to correlate pretherapeutic ventrolateral thalamus functional connectivity (FC) with clinical results 1 year after stereotactic radiosurgical thalamotomy (SRS-T) for drug-resistant ET. Data from 12 healthy control individuals were additionally included. Methods Resting state was acquired for 17 consecutive (right-handed) patients, before and 1 year after left unilateral SRS-T. Standard tremor scores were evaluated pretherapeutically and 1 year after SRS-T. Tremor network was investigated using region of interest, left ventrolateral ventral (VLV) cluster, obtained from pretherapeutic diffusion magnetic resonance imaging. Seed-based FC was obtained as correlations between the time courses of the VLV and that of every other voxel. The seed-connectivity maps were obtained pretherapeutically and correlated across all patients with clinical outcome 1 year after SRS-T. One-year magnetic resonance signature volume was always located inside VLV and did not correlate with reported seed-FC measures (P > 0.05). Results We report statistically significant correlations between pretherapeutic VLV FC with clinical outcome for 1) right visual association area (Brodmann area, BA19) predicting 1 year activities of daily living decrease (Punc = 0.02); 2) left fusiform gyrus (BA37) predicting 1 year head tremor score improvement (Punc = 0.04); and 3) posterior cingulate (left BA23, Puncor = 0.009), lateral temporal cortex (right BA21, Punc = 0.02) predicting time to tremor arrest. Conclusions Our results suggest that pretherapeutic resting-state seed-FC of left VLV predicts tremor arrest after SRS-T for ET. Visual areas are identified as the main regions in this correlation.

Teresa R. Franklin - One of the best experts on this subject based on the ideXlab platform.

Constantin Tuleasca - One of the best experts on this subject based on the ideXlab platform.

  • pretherapeutic motor thalamus resting state functional connectivity with visual areas predicts tremor arrest after thalamotomy for essential tremor tracing the cerebello thalamo visuo motor network
    World Neurosurgery, 2018
    Co-Authors: Constantin Tuleasca, Elena Najdenovska, Jean Regis, Tatiana Witjas, Nadine Girard, Jerome Champoudry, Mohamed Faouzi, Jeanphilippe Thiran, Meritxell Bach Cuadra
    Abstract:

    Background Essential tremor (ET) is a common movement disorder. Resting-state functional magnetic resonance imaging is a noninvasive Neuroimaging Method acquired in absence of task. Objective Our study aimed to correlate pretherapeutic ventrolateral thalamus functional connectivity (FC) with clinical results 1 year after stereotactic radiosurgical thalamotomy (SRS-T) for drug-resistant ET. Data from 12 healthy control individuals were additionally included. Methods Resting state was acquired for 17 consecutive (right-handed) patients, before and 1 year after left unilateral SRS-T. Standard tremor scores were evaluated pretherapeutically and 1 year after SRS-T. Tremor network was investigated using region of interest, left ventrolateral ventral (VLV) cluster, obtained from pretherapeutic diffusion magnetic resonance imaging. Seed-based FC was obtained as correlations between the time courses of the VLV and that of every other voxel. The seed-connectivity maps were obtained pretherapeutically and correlated across all patients with clinical outcome 1 year after SRS-T. One-year magnetic resonance signature volume was always located inside VLV and did not correlate with reported seed-FC measures (P > 0.05). Results We report statistically significant correlations between pretherapeutic VLV FC with clinical outcome for 1) right visual association area (Brodmann area, BA19) predicting 1 year activities of daily living decrease (Punc = 0.02); 2) left fusiform gyrus (BA37) predicting 1 year head tremor score improvement (Punc = 0.04); and 3) posterior cingulate (left BA23, Puncor = 0.009), lateral temporal cortex (right BA21, Punc = 0.02) predicting time to tremor arrest. Conclusions Our results suggest that pretherapeutic resting-state seed-FC of left VLV predicts tremor arrest after SRS-T for ET. Visual areas are identified as the main regions in this correlation.

Ponnada A Narayana - One of the best experts on this subject based on the ideXlab platform.

  • phase sensitive t1 inversion recovery imaging a time efficient interleaved technique for improved tissue contrast in Neuroimaging
    American Journal of Neuroradiology, 2005
    Co-Authors: Khader M Hasan, Clark W Sitton, Jerry S Wolinsky, Ponnada A Narayana
    Abstract:

    BACKGROUND AND PURPOSE: High tissue contrast and short acquisition time are desirable when scanning patients. The purpose of this report is to describe the implementation of a new technique for generating high gray matter (GM) and white matter (WM) contrast in a short scan time, make a quantitative evaluation of the contrast efficiency, and explore its potential applications in Neuroimaging. Method: A fully interleaved T1-weighted inversion recovery (T1IR) sequence with phase-sensitive reconstruction (PS-T1IR) is implemented. This sequence is compared with conventional T1-weighted spin-echo imaging (T1SE) and T1-weighted fluid-attenuated inversion recovery (T1FLAIR). The time efficiency and contrast enhancement have been quantitatively analyzed in normal volunteers. The performance of the sequence is evaluated in >30 patients with neurologic disorders. The sensitivity of PS-T1IR relative to T1SE in detecting gadolinium enhancements is also evaluated. RESULTS: PS-T1IR is more time-efficient than T1SE and generates better GM-WM contrast. It results in the best contrast-to-noise ratio (CNR) efficiency (1.16) compared with T1FLAIR (0.73) and T1SE (0.23). For a typical clinical protocol, PS-T1IR takes only 1:30 minutes versus 2:40 minutes for T1SE imaging for the whole brain coverage. Although gadolinium enhancements are detected with comparable sensitivity on both PS-T1IR and T1SE sequences, in certain instances, the latter sequence appears to be more sensitive in demonstrating gadolinium enhancements within WM. CONCLUSION: PS-T1IR has the highest CNR efficiency compared with T1FLAIR and T1SE. It is a very practical technique for neuroradiologic applications.

  • phase sensitive t1 inversion recovery imaging a time efficient interleaved technique for improved tissue contrast in Neuroimaging
    American Journal of Neuroradiology, 2005
    Co-Authors: Ping Hou, Khader M Hasan, Clark W Sitton, Jerry S Wolinsky, Ponnada A Narayana
    Abstract:

    BACKGROUND AND PURPOSE: High tissue contrast and short acquisition time are desirable when scanning patients. The purpose of this report is to describe the implementation of a new technique for generating high gray matter (GM) and white matter (WM) contrast in a short scan time, make a quantitative evaluation of the contrast efficiency, and explore its potential applications in Neuroimaging. Method: A fully interleaved T1-weighted inversion recovery (T1IR) sequence with phase-sensitive reconstruction (PS-T1IR) is implemented. This sequence is compared with conventional T1-weighted spin-echo imaging (T1SE) and T1-weighted fluid-attenuated inversion recovery (T1FLAIR). The time efficiency and contrast enhancement have been quantitatively analyzed in normal volunteers. The performance of the sequence is evaluated in >30 patients with neurologic disorders. The sensitivity of PS-T1IR relative to T1SE in detecting gadolinium enhancements is also evaluated. RESULTS: PS-T1IR is more time-efficient than T1SE and generates better GM-WM contrast. It results in the best contrast-to-noise ratio (CNR) efficiency (1.16) compared with T1FLAIR (0.73) and T1SE (0.23). For a typical clinical protocol, PS-T1IR takes only 1:30 minutes versus 2:40 minutes for T1SE imaging for the whole brain coverage. Although gadolinium enhancements are detected with comparable sensitivity on both PS-T1IR and T1SE sequences, in certain instances, the latter sequence appears to be more sensitive in demonstrating gadolinium enhancements within WM. CONCLUSION: PS-T1IR has the highest CNR efficiency compared with T1FLAIR and T1SE. It is a very practical technique for neuroradiologic applications.