horizontal view t2 mri radiograph
This radiograph is a view of the brain taken in the same plane, horizontally, closer to the plane of the brain section (see Figure 27), but a little higher than the previous radiograph. Parameters of the MRI have been adjusted to generate a T2-weighted image (see explanation with Figure 3). In this view, the CSF of the ventricles is white, while the bones of the skull are dark.
This MRI shows the brain as if it were an anatomical specimen (compare with the previous illustration) — there is a good differentiation between the gray matter and the white matter. There is a clear visualization of the basal ganglia and its subdivisions (head of the caudate, lenti-form nucleus), as well as the thalamus. (Note: The line separating the putamen from the globus pallidus can "almost" be seen on the right side of the photograph.) In addition, the area of the internal capsule is also clearly seen.
The anterior horns of the lateral ventricle are present, and the section has passed through the formina of Monro (see Figure 20A, Figure 20B, and Figure 21). The lateral ventricle posteriorly is cut at the level of its widening, the atrium or trigone, as it curves into the temporal lobe (see Figure 20A). The third ventricle is in the midline, between the thalami (see Figure 6, Figure 7, and Figure 9A).
The linear marking in the white matter behind the atrium likely represents the optic radiation, from the lateral geniculate to the calcarine cortex (see Figure 41A and Figure 41C).
Clinical Aspect
The MRI has proved to be invaluable in assessing lesions of the CNS — infarcts, tumors, plaques of multiple sclerosis, and numerous other lesions. An MRI can also be enhanced with intravenous gadolinium, which escapes with the blood when there is a breakdown of the BBB, and helps in the evaluation of pathology, such as tumors.
Tables of skull
Marrow of skull
Gray matter White matter
Caudate n. (head)
Lentiform n. (putamen and globus pallidus)
Thalamus
Optic radiation
Tables of skull
Marrow of skull
Gray matter White matter
Caudate n. (head)
Lentiform n. (putamen and globus pallidus)
Thalamus
Optic radiation
Lateral ventricle (anterior horn)
Internal capsule:
Anterior limb Posterior limb
Foramen of Monro 3rd ventricle
Lateral ventricle (atrium)
Lateral ventricle (anterior horn)
Internal capsule:
Anterior limb Posterior limb
Foramen of Monro 3rd ventricle
Lateral ventricle (atrium)
F = Frontal lobe P = Parietal lobe O = Occipital lobe
FIGURE 28B: Basal Ganglia 8 — MRI: Horizontal View (radiograph)
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