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IMAGE INTERPRETATION · BRAIN IMAGING

Normal Tc-99m ECD Brain SPECT: Gray vs White Matter

Brain perfusion SPECT (Tc-99m ECD), transverse slices — normal study
Brain perfusion SPECT (Tc-99m ECD), transverse slices — normal study

Provided clinical image

Question

These transverse brain slices show symmetric, bilateral tracer distribution throughout the cerebral cortex with a uniform appearance. In a properly acquired normal brain perfusion study, which description best characterizes the expected tracer distribution pattern?

  1. AWhite matter structures show higher uptake than gray matter cortex due to greater myelinated fiber density
  2. BGray and white matter display identical uptake levels with no differentiation visible between brain structures
  3. CGray matter cortex and basal ganglia show higher uptake than white matter, with minimal activity in ventricular regions
  4. DActivity is confined to deep white matter with cortical gray matter appearing nearly photopenic throughout the study
Show the answer and explanation

C. Gray matter cortex and basal ganglia show higher uptake than white matter, with minimal activity in ventricular regions

In a normal brain perfusion SPECT, gray matter structures — including the cerebral cortex, basal ganglia, thalami, and cerebellum — show significantly higher tracer uptake compared to white matter because they have greater metabolic demand and blood flow per unit volume. The ventricular regions appear as areas of very low or absent activity. Clear gray-white matter differentiation is also an important quality indicator: poor differentiation may suggest technical issues, sedation effects, or generalized hypoperfusion.

More brain imaging images

Brain perfusion SPECT (Tc-99m ECD), transverse slices — normal studyBrain SPECT: When to Image After ECD Injection DaTSCAN (I-123 ioflupane) SPECT — midbrain axial sliceDaTscan (I-123 Ioflupane): What It Evaluates Tc-99m HMPAO or ECD brain perfusion SPECT — normal distributionNormal Brain Perfusion SPECT with Tc-99m HMPAO Brain perfusion SPECT — transaxial, coronal, sagittal, and temporal slices showing regional cerebral blood flow pattern in dementiaAlzheimer’s Disease on Brain Perfusion SPECT DaTSCAN (I-123 ioflupane) SPECT — normal striatal uptakeParkinson’s Disease on DaTscan: Loss of the Comma Shape Brain perfusion SPECT — frontal lobe hypoperfusion patternFrontotemporal Dementia on Brain Perfusion SPECT
← Brain Perfusion SPECT: Injection EnvironmentBrain SPECT: When to Image After ECD Injection →

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