Acronym

ADC - Apparent Diffusion Coefficient

Apparent Diffusion Coefficient

Quantitative map derived from DWI showing water diffusion

Expansion

Apparent Diffusion Coefficient

Purpose

Confirms restricted diffusion (low ADC equals restricted equals ischaemia or tumour)

Clinical Context

ADC calculated from DWI with different b-values. Units millimetres squared per second. Ischaemic stroke shows low ADC. High ADC suggests T2 shine-through (non-specific).

  • DWI
  • Diffusion metrics

Key Points

  • Always check ADC when interpreting DWI; bright DWI with low ADC equals restricted diffusion equals abnormal