Systematic Approach to Reading a Non-Contrast Head CT Scan.

Systematic Approach to Reading a Non-Contrast Head CT Scan

Systematic Approach

Assess each component of the intracranial cavity

1. Blood2. Brain3. Bone4. CSF

Blood

1. Epidural Hematoma (EDH)Arterial Bleed: High-Pressure “Lens” ShapeMiddle Meningeal Laceration (Skull Fracture)

2. Subdural Hematoma (SDH)Venous Bleed: Low-Pressure “Crescent” ShapeAcute / Chronic (Is Patient Anticoagulated? Alcoholic?)

3. Subarachnoid Hemorrhage (SAH)Traumatic / Aneurysmal

4. Intraventricular Hemorrhage (IVH)5. Intraparenchymal Hemorrhage (IPH)

Hypertensive Basal Ganglia or Lobar Cerebral Contusion “Coup-Contrecoup”

EDH

SDH: Acute/Chronic

SAH (Aneurysmal)

IVH

IPH

IPH

Contusion

Coup (Red) Contrecoup Contusion (Orange) (at 180 degrees)

Brain

1. Symmetry (of Hemispheres)Hyper-/Hypodensities (Masses, Edema, Stroke)

2. Grey/White Matter BorderLost Grey-White Differentiation in Anoxic Injury

3. Midline Shift4. Gyri/Sulci

Wide Sulci: Atrophy Effaced Sulci: Edematous “Tight/Swollen” Brain

5. Pneumocephalus (Air in Brain)Open Fracture (or Craniotomy)Fracture through Sinus

Mass

Midline Shift

Sulci/Gyri: Atrophy/Edema

Bone

1. FracturesEspecially Temporal Bones

2. Sinuses & Air CellsLook for Air-Fluid Levels

Pneumocephalus

Temporal Bone Fracture

CSF: Ventricles & Cisterns

1. VentriclesBlood in Ventricles?Effacement/Asymmetry: Compression from Mass/HematomaHydrocephalus

Atrophy (“Ex Vacuo”) Communicating / Obstructive HydrocephalusIf Obstructive, Where?

Look at Lateral, 3rd, and 4th Ventricles

2. CisternsLook for Effacement (Edema/Early Herniation)Look for Blood

Cisterns/Effacement

Ventricles/Hydrocephalus