How to measure substantia nigra hyperechogenicity in Parkinson disease: detailed guide with video.
The detection of an enlarged echogenic size ("hyperechogenicity") of the substantia nigra on transcranial sonography is increasingly used for the early and differential diagnosis of Parkinson disease. However, the diagnostic value of substantia nigra sonography depends on the quality of its execution. This article with an accompanying video presents a step-by-step description and demonstration of ultrasound system settings, typical errors in assessment of the substantia nigra, planimetric measurement of substantia nigra echogenicity according to current guidelines, and its diagnostic implications in 2 exemplary patients with parkinsonism. Published cutoff values for grading substantia nigra hyperechogenicity with different ultrasound systems and novel technologies are reviewed.
Department of Neurology, University of Rostock, Gehlsheimer Strasse 20, D-18147 Rostock, Germany. E-email: uwe.walter@med.uni-rostock.de.
Uwe
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Walter
D000368:Aged; D000465:Algorithms; D004453:Echoencephalography / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D010300:Parkinson Disease / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013378:Substantia Nigra / Q000000981:diagnostic imaging*
Parkinson disease; methodological standard; parkinsonism; substantia nigra; transcranial sonography