Presentation
The patient exhibited upper limb choreic and dystonic movements. There were subtle facial movements, motor impersistence of the tongue and lower limb toe chorea. Gait was unsteady and wide-based. There was a recent psychiatric admission due to presentation with a persecutory delusion that his father had locked up his (imaginary) daughter.
Patient Data
Marked atrophy of the caudate nucleus and putamen are noted. No restricted diffusion or susceptibility artifact. No enhancing lesions on the post-contrast study.
There is atrophy of the frontoparietal and occipital lobes. No atrophy of the cerebellum.
Neuropsychiatry Unit Cognitive Assessment Tool (NUCOG) performed on this patient.
Scores across most domains are more than two standard deviations below normal.
Reduced uptake is seen in the heads of the caudate nuclei, worse on the left side. In addition, hypoperfusion is seen in the parietal lobes particularly in the left superior parietal lobe. The perfusion is also mildly reduced in the mesial temporal lobes.
MRI Frontal horn width to intercaudate ratio
This frontal horn width to intercaudate ratio (FH/CC) is demonstrated in this image taken from the above patient.
FH/CC = 3.33/2.44 = 1.36 (normal 2.2-2.6)
Case Discussion
This patient presented with moderate stage symptoms (motor, cognitive, psychiatric). Gene testing demonstrated HTT allele I size 18, allele II size 46 (normal range <36). The MRI brain shows significant global atrophy. The caudate heads are flat and putamen is atrophied.
These are typical and characteristic appearances of Huntington's disease.