The Experts below are selected from a list of 27 Experts worldwide ranked by ideXlab platform

Juan Carlos Fernandez-miranda - One of the best experts on this subject based on the ideXlab platform.

  • 376 Human Connectome-Based Tractographic Atlas of the Brainstem Connections and Surgical Approaches
    Neurosurgery, 2017
    Co-Authors: Antonio Meola, Wendy Fellows-mayle, Jared Weed, Juan Carlos Fernandez-miranda
    Abstract:

    Abstract INTRODUCTION The brainstem is one of the most challenging areas for the neuro- surgeon because of the limited space between gray matter nuclei and white matter pathways. Diffusion tensor imaging based tractography has been used to study the brainstem structure, but the angular and spatial resolution could be improved further with advanced diffusion magnetic resonance imaging (MRI). Objective: To construct a high angular/spatial resolution, wide-population based, comprehensive tractography atlas that presents an anatomical review of the surgical approaches to the brainstem. METHODS We applied advanced diffusion MRI finer tractography to a population-based atlas constructed with data from a total of 488 subjects from the Human Connectome Project-488. Five formalin-fixed brains were studied for surgical landmarks. Luxol Fast Blue stained histological sections were used to validate the results of tractography. RESULTS >We acquired the tractography of the major brainstem pathways and vali- dated them with histological analysis. The pathways included the cerebellar peduncles, corticospinal tract, corticopontine tracts, medial lemniscus, lateral lemniscus, spino- thalamic tract, rubrospinal tract, central tegmental tract, medial Longitudinal Fasciculus, and Dorsal Longitudinal Fasciculus. Then, the reconstructed 3-dimensional brainstem structure was sectioned at the level of classic surgical approaches, namely supra- collicular, infracollicular, lateral mesencephalic, perioculomotor, peritrigeminal, antero- lateral (to the medulla), and retro-olivary approaches. CONCLUSION The advanced diffusion MRI fiber tracking is a powerful tool to explore the brainstem neuroanatomy and to achieve a better understanding of surgical approaches.

  • Human Connectome-Based Tractographic Atlas of the Brainstem Connections and Surgical Approaches.
    Neurosurgery, 2016
    Co-Authors: Antonio Meola, Wendy Fellows-mayle, Jared Weed, Juan Carlos Fernandez-miranda
    Abstract:

    BACKGROUND: The brainstem is one of the most challenging areas for the neurosurgeon because of the limited space between gray matter nuclei and white matter pathways. Diffusion tensor imaging-based tractography has been used to study the brainstem structure, but the angular and spatial resolution could be improved further with advanced diffusion magnetic resonance imaging (MRI). OBJECTIVE: To construct a high-angular/spatial resolution, wide-population-based, comprehensive tractography atlas that presents an anatomical review of the surgical approaches to the brainstem. METHODS: We applied advanced diffusion MRI fiber tractography to a population-based atlas constructed with data from a total of 488 subjects from the Human Connectome Project-488. Five formalin-fixed brains were studied for surgical landmarks. Luxol Fast Blue-stained histological sections were used to validate the results of tractography. RESULTS: We acquired the tractography of the major brainstem pathways and validated them with histological analysis. The pathways included the cerebellar peduncles, corticospinal tract, corticopontine tracts, medial lemniscus, lateral lemniscus, spinothalamic tract, rubrospinal tract, central tegmental tract, medial Longitudinal Fasciculus, and Dorsal Longitudinal Fasciculus. Then, the reconstructed 3-dimensional brainstem structure was sectioned at the level of classic surgical approaches, namely supracollicular, infracollicular, lateral mesencephalic, perioculomotor, peritrigeminal, anterolateral (to the medulla), and retro-olivary approaches. CONCLUSION: The advanced diffusion MRI fiber tracking is a powerful tool to explore the brainstem neuroanatomy and to achieve a better understanding of surgical approaches. ABBREVIATIONS: CN, cranial nerveCPT, corticopontine tractCST, corticospinal tractCTT, central tegmental tractDLF, Dorsal Longitudinal FasciculusHCP, Human Connectome ProjectML, medial lemniscusMLF, medial Longitudinal FasciculusRST, rubrospinal tractSTT, spinothalamic tract.

Erich Talamoni Fonoff - One of the best experts on this subject based on the ideXlab platform.

  • Deep brain stimulation modulates hypothalamic-brainstem fibers in cluster headache: case report.
    Journal of Neurosurgery, 2019
    Co-Authors: Sergio Adrian Fernandes Dantas, Eduardo Joaquim Lopes Alho, Juliano Jose Da Silva, Nilson N. Mendes Neto, Erich Talamoni Fonoff, Clement Hamani
    Abstract:

    : Hypothalamic deep brain stimulation (DBS) has been used for more than a decade to treat cluster headache (CH) but its mechanisms remain poorly understood. The authors have successfully treated a patient with CH using hypothalamic DBS and found that the contact used for chronic stimulation was located in a white matter region posterior to the mammillary bodies. Fiber tracts crossing that region were the medial forebrain bundle and those interconnecting the hypothalamus and brainstem, including the Dorsal Longitudinal Fasciculus. Because the stimulation of axons is an important mechanism of DBS, some of its clinical effects in CH may be related to the stimulation of fibers interconnecting the hypothalamus and brainstem.

  • Stereotactic disconnection of hypothalamic hamartoma to control seizure and behavior disturbance: case report and literature review
    Neurosurgical Review, 2008
    Co-Authors: Antonio Nogueira Almeida, Erich Talamoni Fonoff, Gerson Ballester, Manoel Jacobsen Teixeira, Raul Marino
    Abstract:

    An 18-year-old boy with refractory epilepsy and aggressiveness associated to a hypothalamic hamartoma was submitted to a stereotactically guided lesion by thermocoagulation. The target was based on magnetic resonance (MR) images merged with computed tomography scan images taken on the day of surgery while patient was on a stereotactic frame. In order to reveal structures not discernible in MR images, the Schaltenbrand digital brain atlas was merged onto the patient’s images. Target and trajectory of the depth electrode were chosen based on three-dimensional imaging reconstructions. A surgical plan was devised to disconnect the hypothalamic hamartoma from the hypothalamus, medial forebrain bundle, Fasciculus princeps, and Dorsal Longitudinal Fasciculus. Our target was placed at the inferior portion of the posterolateral component of the hamartoma, bordering the normal hypothalamus. The patient evolved with marked lessening of aggressiveness. Seizure frequency was reduced from several seizures per day to less than one tonic-clonic seizure during sleep per month and only two episodes suggestive of partial complex seizures during daytime. These results have remained consistent over a 24-month postoperative follow-up. Functional neuroanatomy of hypothalamic connections involved in seizure propagation and aggressive behavior was reviewed.

Antonio Meola - One of the best experts on this subject based on the ideXlab platform.

  • 376 Human Connectome-Based Tractographic Atlas of the Brainstem Connections and Surgical Approaches
    Neurosurgery, 2017
    Co-Authors: Antonio Meola, Wendy Fellows-mayle, Jared Weed, Juan Carlos Fernandez-miranda
    Abstract:

    Abstract INTRODUCTION The brainstem is one of the most challenging areas for the neuro- surgeon because of the limited space between gray matter nuclei and white matter pathways. Diffusion tensor imaging based tractography has been used to study the brainstem structure, but the angular and spatial resolution could be improved further with advanced diffusion magnetic resonance imaging (MRI). Objective: To construct a high angular/spatial resolution, wide-population based, comprehensive tractography atlas that presents an anatomical review of the surgical approaches to the brainstem. METHODS We applied advanced diffusion MRI finer tractography to a population-based atlas constructed with data from a total of 488 subjects from the Human Connectome Project-488. Five formalin-fixed brains were studied for surgical landmarks. Luxol Fast Blue stained histological sections were used to validate the results of tractography. RESULTS >We acquired the tractography of the major brainstem pathways and vali- dated them with histological analysis. The pathways included the cerebellar peduncles, corticospinal tract, corticopontine tracts, medial lemniscus, lateral lemniscus, spino- thalamic tract, rubrospinal tract, central tegmental tract, medial Longitudinal Fasciculus, and Dorsal Longitudinal Fasciculus. Then, the reconstructed 3-dimensional brainstem structure was sectioned at the level of classic surgical approaches, namely supra- collicular, infracollicular, lateral mesencephalic, perioculomotor, peritrigeminal, antero- lateral (to the medulla), and retro-olivary approaches. CONCLUSION The advanced diffusion MRI fiber tracking is a powerful tool to explore the brainstem neuroanatomy and to achieve a better understanding of surgical approaches.

  • Human Connectome-Based Tractographic Atlas of the Brainstem Connections and Surgical Approaches.
    Neurosurgery, 2016
    Co-Authors: Antonio Meola, Wendy Fellows-mayle, Jared Weed, Juan Carlos Fernandez-miranda
    Abstract:

    BACKGROUND: The brainstem is one of the most challenging areas for the neurosurgeon because of the limited space between gray matter nuclei and white matter pathways. Diffusion tensor imaging-based tractography has been used to study the brainstem structure, but the angular and spatial resolution could be improved further with advanced diffusion magnetic resonance imaging (MRI). OBJECTIVE: To construct a high-angular/spatial resolution, wide-population-based, comprehensive tractography atlas that presents an anatomical review of the surgical approaches to the brainstem. METHODS: We applied advanced diffusion MRI fiber tractography to a population-based atlas constructed with data from a total of 488 subjects from the Human Connectome Project-488. Five formalin-fixed brains were studied for surgical landmarks. Luxol Fast Blue-stained histological sections were used to validate the results of tractography. RESULTS: We acquired the tractography of the major brainstem pathways and validated them with histological analysis. The pathways included the cerebellar peduncles, corticospinal tract, corticopontine tracts, medial lemniscus, lateral lemniscus, spinothalamic tract, rubrospinal tract, central tegmental tract, medial Longitudinal Fasciculus, and Dorsal Longitudinal Fasciculus. Then, the reconstructed 3-dimensional brainstem structure was sectioned at the level of classic surgical approaches, namely supracollicular, infracollicular, lateral mesencephalic, perioculomotor, peritrigeminal, anterolateral (to the medulla), and retro-olivary approaches. CONCLUSION: The advanced diffusion MRI fiber tracking is a powerful tool to explore the brainstem neuroanatomy and to achieve a better understanding of surgical approaches. ABBREVIATIONS: CN, cranial nerveCPT, corticopontine tractCST, corticospinal tractCTT, central tegmental tractDLF, Dorsal Longitudinal FasciculusHCP, Human Connectome ProjectML, medial lemniscusMLF, medial Longitudinal FasciculusRST, rubrospinal tractSTT, spinothalamic tract.

Raul Marino - One of the best experts on this subject based on the ideXlab platform.

  • Stereotactic disconnection of hypothalamic hamartoma to control seizure and behavior disturbance: case report and literature review
    Neurosurgical Review, 2008
    Co-Authors: Antonio Nogueira Almeida, Erich Talamoni Fonoff, Gerson Ballester, Manoel Jacobsen Teixeira, Raul Marino
    Abstract:

    An 18-year-old boy with refractory epilepsy and aggressiveness associated to a hypothalamic hamartoma was submitted to a stereotactically guided lesion by thermocoagulation. The target was based on magnetic resonance (MR) images merged with computed tomography scan images taken on the day of surgery while patient was on a stereotactic frame. In order to reveal structures not discernible in MR images, the Schaltenbrand digital brain atlas was merged onto the patient’s images. Target and trajectory of the depth electrode were chosen based on three-dimensional imaging reconstructions. A surgical plan was devised to disconnect the hypothalamic hamartoma from the hypothalamus, medial forebrain bundle, Fasciculus princeps, and Dorsal Longitudinal Fasciculus. Our target was placed at the inferior portion of the posterolateral component of the hamartoma, bordering the normal hypothalamus. The patient evolved with marked lessening of aggressiveness. Seizure frequency was reduced from several seizures per day to less than one tonic-clonic seizure during sleep per month and only two episodes suggestive of partial complex seizures during daytime. These results have remained consistent over a 24-month postoperative follow-up. Functional neuroanatomy of hypothalamic connections involved in seizure propagation and aggressive behavior was reviewed.

T Hayakawa - One of the best experts on this subject based on the ideXlab platform.

  • Descending projections from the paraventricular hypothalamic nucleus to the spinal cord: anterograde tracing study in the rat.
    Okajimas folia anatomica Japonica, 1995
    Co-Authors: J Q Zheng, M Seki, T Hayakawa
    Abstract:

    We investigated the direct projections from the paraventricular hypothalamic nucleus (PVH) to the spinal cord. When Phaseolus vulgaris leucoagglutinin (PHA-L) was injected into the PVH, labeled descending fibers were observed running bilaterally through three pathways. The first pathway ran into the Dorsal Longitudinal Fasciculus and projected to the central gray matter, Edinger-Westphal nucleus, pedunculopontine tegmental nucleus, nucleus of the locus ceruleus and parabrachial nucleus. The second and third pathways coursed through the medial forebrain bundle, ventral tegmental area, and ventral part of the medulla oblongata. At the medulla oblongata, the second pathway curved dorsolaterally and joined Rexed's lamina V of C1 after giving many projections to the nucleus ambiguus, nucleus of the solitary tract, Dorsal motor nucleus of the vagus, and a few to the area postrema. The fibers descended through lamina V until C5, and coursed through lamina I from C6 to the upper coccygeal segments. They gave collateral projections to lamina I from the cervical through the upper coccygeal segments. The third pathway coursed laterally and descended through the lateral funiculus after giving projections to the lateral reticular nucleus and the marginal layer of the spinal trigeminal nucleus. These fibers gave off many projections to the intermediolateral cell column of the thoracic cord and the sacral parasympathetic nucleus. Lamina X received many projections from the fibers of the lateral funiculus at C5 through the b-segment of sacral spinal cord. These results indicate that the PVH may integrate directly with the medullary and spinal autonomic regulatory nuclei, including the vagus complex, sympathetic intermediolateral cell column, laminae I and X, and sacral parasympathetic nucleus.