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Topic

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Lateral longitudinal fasciculus

The lateral longitudinal fasciculus is a prominent white matter tract located within the central nervous system, playing a key role in interconnecting various regions of the brain. It is primarily involved in facilitating communication between cortical and subcortical structures, contributing to complex neurological functions. Though less commonly discussed than the medial longitudinal fasciculus, the lateral longitudinal fasciculus remains essential for coordinating sensory and motor pathways across different brain areas.

Synonyms

  • Lateral fasciculus

  • Lateral longitudinal bundle

Arterial Supply

  • Primarily supplied by small perforating branches of the middle cerebral artery (MCA)

  • Additional minor contributions from branches of the anterior cerebral artery (ACA)

  • Segmental arterial supply depending on the specific region within the brain

Venous Drainage

  • Drained via deep cerebral veins

  • Ultimately empties into the internal cerebral vein and then the great cerebral vein of Galen

  • Regional superficial venous drainage may also contribute depending on tract location

Function

  • Acts as a conduit for communication between different lobes of the brain, particularly linking frontal, parietal, and temporal regions

  • Supports sensorimotor integration

  • Facilitates cognitive processing and coordination of voluntary movement

  • May play a role in language pathways and higher-order associative functions

MRI Appearance

  • T1-weighted Images:

    • Appears as a hypointense (dark) band, consistent with other white matter tracts

    • Well-delineated against adjacent gray matter

  • T2-weighted Images:

    • Appears mild hyperintense, as typical for myelinated white matter

    • Easily distinguished from gray matter structures

  • FLAIR Images:

    • Usually shows as a moderately hyperintense band

    • White matter pathology (e.g., demyelination or infarct) within the fasciculus may appear as focal areas of high signal

CT Appearance

  • Difficult to visualize directly due to limited contrast resolution for white matter tracts

  • Appears isodense to surrounding brain tissue under normal conditions

MRI images

lateral longitudinal fasciculus mri 3t axial image