Brain parenchyma sonography discriminates Parkinson's disease and atypical parkinsonian syndromes.

Abstract

To the Editor: We read with interest the article by Walter et al. regarding sonographic findings in brain parenchyma in Parkinson disease (PD), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP).1 However, we regard the conclusion that this might become a standard investigation to aid discrimination of PD from atypical parkinsonian syndromes (MSA, PSP) as premature, for the following reasons. 1. This study examined patients with established disease with a mean disease duration of 5.7 years for PD, 3.7 years for MSA, and 4.8 years for PSP and clinically probable syndromes. Confirmation of syndrome type at this stage is not as helpful as detection would be at an earlier disease stage when diagnosis is clinically uncertain. Before this test can be deemed useful clinically it must show adequate sensitivity and specificity in patients with clinically uncertain parkinsonian syndromes where the differential …