Normal CT Brain (Non-contrast) — Key Radiological Features (Concise)
1. Symmetry
- Bilateral cerebral hemispheres symmetrical
- No midline shift
- Falx cerebri in midline
2. Grey–White Matter Differentiation
- Clear distinction:
- Grey matter (cortex, basal ganglia) → slightly hyperdense
- White matter → slightly hypodense
- Preserved corticomedullary junction
3. Ventricular System
- Lateral, 3rd, 4th ventricles:
- Normal size and configuration
- Symmetrical
- No dilatation or compression
4. Cisterns & Sulci
- Basal cisterns (suprasellar, ambient, quadrigeminal) → open and well-defined
- Cortical sulci:
- Normal for age
- No effacement (→ edema) or prominence (→ atrophy)
5. Basal Ganglia & Thalami
- Normal density and symmetry
- No focal hypo/hyperdense lesions
6. Brainstem & Cerebellum
- Normal size, contour, and density
- No focal lesion or compression
7. No Abnormal Densities
- No:
- Hyperdensity → hemorrhage
- Hypodensity → infarct/edema
- No calcification (except physiological: pineal, choroid plexus)
8. Midline Structures
- Falx, septum pellucidum → central
- No mass effect or shift
9. Bone & Extra-axial Structures
- Skull vault intact (no fracture)
- No:
- Extradural/subdural collection
- Scalp swelling
10. Orbits & Sinuses (Screening)
- Orbits normal
- Paranasal sinuses:
- Air-filled (no fluid level or opacification)
Ultra-short Mnemonic: “S G V C B B M B O”
- Symmetry
- Grey–white differentiation
- Ventricles
- Cisterns/sulci
- Basal ganglia
- Brainstem/cerebellum
- Midline
- Bones/extra-axial
- Orbits/sinuses


