Basal ganglia echogenicity in tauopathies

Area of Science:

• Neurology
• Neuroimaging
• Diagnostic Tools

Background:

• Transcranial sonography (TCS) is increasingly recognized for its utility in diagnosing Parkinson's disease.
• The diagnostic value of basal ganglia abnormalities detected by TCS in atypical parkinsonian syndromes requires further investigation.

Purpose of the Study:

• To assess the relevance of basal ganglia abnormalities using TCS in patients with progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS).
• To evaluate the diagnostic accuracy of specific TCS findings for differentiating between PSP and CBS.

Main Methods:

• Utilized transcranial sonography (TCS) to examine 20 patients with PSP and 13 patients with CBS.
• Assessed the echogenicity of the substantia nigra (SN) and lenticular nucleus (LN) in all participants.

Main Results:

• Substantia nigra (SN) hyperechogenicity was observed in 66.6% of CBS patients but in none of the PSP patients.
• Lenticular nucleus (LN) hyperechogenicity was detected in 9/20 PSP patients and 0/11 CBS patients.
• A combination of SN isoechogenicity and LN hyperechogenicity demonstrated 100% sensitivity and positive predictive value for PSP diagnosis.

Conclusions:

• Substantia nigra (SN) hyperechogenicity on TCS should prompt consideration of corticobasal syndrome (CBS) in patients with parkinsonian syndromes.
• Normal SN echogenicity coupled with LN hyperechogenicity effectively excludes CBS, strongly suggesting PSP.