PET imaging in Huntington disease shows decreased glucose metabolism in which brain structures?

PET imaging in Huntington disease shows decreased glucose metabolism in which brain structures?

• A. Caudate nucleus and putamen.
• B. Frontal cortex.
• C. Hippocampus.
• D. Occipital lobe.

Answer: (A)

In Huntington disease, the most pronounced metabolic decline on PET occurs in the striatum—the caudate nucleus and putamen. This region is the primary site of neurodegeneration, with loss of the medium spiny GABAergic neurons that disrupt cortico-basal ganglia circuits. As these neurons die, the local neuronal activity and glucose utilization drop, producing decreased FDG uptake on PET scans. The frontal cortex and other areas may show later involvement, but early hypometabolism is concentrated in the caudate and putamen. The hippocampus and occipital lobe are not the characteristic sites of early metabolic change in Huntington.

In Huntington disease, the most pronounced metabolic decline on PET occurs in the striatum—the caudate nucleus and putamen. This region is the primary site of neurodegeneration, with loss of the medium spiny GABAergic neurons that disrupt cortico-basal ganglia circuits. As these neurons die, the local neuronal activity and glucose utilization drop, producing decreased FDG uptake on PET scans. The frontal cortex and other areas may show later involvement, but early hypometabolism is concentrated in the caudate and putamen. The hippocampus and occipital lobe are not the characteristic sites of early metabolic change in Huntington.