What are the white matter pathways in the brain?
Three major white matter pathways connect the posterior temporal region and the adjacent inferior parietal lobule with the lateral frontal cortex: the arcuate fasciculus (AF), and the second and third branches of the superior longitudinal fasciculus (SLF II and SLF III).
What is a perivascular space?
Perivascular spaces are fluid-filled spaces that follow a typical course of a vessel penetrating/transversing the brain through gray or white matter.
What is prominent perivascular?
Perivascular spaces (PVSs), also known as Virchow-Robin spaces, are pial-lined, fluid-filled structures found in characteristic locations throughout the brain. They can become abnormally enlarged or dilated and in rare cases can cause hydrocephalus.
What is a perivascular cyst?
What are lacunar spaces?
Lacunar infarcts are defined as small subcortical and deep infarcts (<15 mm in diameter) due to occlusion of a single deep penetrating artery and may be asymptomatic or present with specific lacunar or other neurological symptoms.
What is T2 and flair Hyperintensities?
Focal hyperintensities in the subcortical white matter demonstrated by T2-weighted or FLAIR images are a common incidental finding in patients undergoing brain MRI for indications other than stroke. They are indicative of chronic microvascular disease.
What is the indirect pathway of the basal ganglia?
The indirect pathway in the basal ganglia consists of excitatory input from the cortex via glutamate action or inhibitory input from the substantia nigra via dopamine action that synapses on inhibitory neurons in the striatum. The striatal neurons project to the external segment of the globus pallidus (GPe).
What are glioependymal (neuroglial) cysts?
Intracranial glioependymal (neuroglial) cysts: a systematic review The data collected from this review shows that GECs are rare and very often are erroneously named. They are congenital benign lesions with a neuroectodermal origin that share many radiological characteristics with a variety of intracranial benign cysts.
What happens to the basal ganglia after a lesion of the basal?
As we have learned so far, when the indirect pathway of the basal ganglia is stimulated, it sends signals to the motor cortex and brainstem, which ultimately inhibit muscle tone. Following a lesion of the basal ganglia, this inhibitory influence is lost and hypertonicity is manifested contralateral to the side of the lesion.
What are neuroneuroglial cysts?
Neuroglial cysts are congenital lesions that develop a sequestration of neural tube embryonic elements that develop into a fluid-filled cavity, lined by glial cell and located within the white matter 4 . They can be intra- or extra-parenchymal with the former being more common. The frontal lobe is thought to be the most typical location 1,3.