Acronym

DWI - Diffusion-Weighted Imaging

Diffusion-Weighted Imaging

MRI sequence sensitive to water motion (Brownian diffusion)

Expansion

Diffusion-Weighted Imaging

Purpose

Detects restricted diffusion (ischaemic stroke, abscess, malignancy)

Clinical Context

DWI uses diffusion-sensitising gradients. Restricted diffusion (cytotoxic oedema) appears bright on DWI and dark on ADC. Confirms acute ischaemia.

  • ADC
  • Stroke imaging
  • Cancer detection

Key Points

  • DWI is most sensitive sequence for acute ischaemic stroke. Abnormal within minutes of symptom onset