Learning Objectives
- Identify the bone and sinus structures of the skull (Diploe, Frontal Sinus).
- Distinguish between the Basal Ganglia components (Caudate, Putamen) and the Thalamus.
- Locate the white matter pathways, specifically the Internal Capsule and Corpus Callosum.
- Trace the dural folds and venous sinuses, including the Falx Cerebri and Superior Sagittal Sinus.
Superficial & Cranial Landmarks
- Musculature: Frontalis (anterior/forehead), Temporalis (lateral/temple), and Occipitalis (posterior/occiput).
- Bone Structure: The Diploe is the spongy bone layer sandwiched between the inner and outer tables of the skull.
- Frontal Sinus: An air-filled cavity within the frontal bone, visible anteriorly.
Dural Structures & Ventricles
- Falx Cerebri: The crescent-shaped fold of dura mater that descends vertically into the longitudinal fissure between the cerebral hemispheres.
- Superior Sagittal Sinus: Located within the superior margin of the falx cerebri; a major venous drainage pathway.
- Lateral Ventricles: The large, C-shaped cavities containing cerebrospinal fluid (CSF).
Deep Gray Matter & White Matter
This section is critical for identifying the Basal Ganglia and their relationship to the internal capsule:
| Structure | Description & Positioning |
|---|---|
| Caudate Nucleus | Located on the floor of the anterior horn of the lateral ventricle. |
| Putamen | The more lateral portion of the basal ganglia is separated from the thalamus by the internal capsule. |
| Thalamus | The large, egg-shaped relay center is located medial to the internal capsule. |
| Internal Capsule | A V-shaped white matter tract. The “knee” (Genu) sits between the anterior and posterior limbs. |
The Corpus Callosum
The primary commissural tract connecting the two hemispheres. In this axial slice, two parts are visible:
- Genu: The anterior portion of the corpus callosum.
- Splenium: The thickened posterior end of the corpus callosum.
Activity