Transcranial brain sonography findings in two main variants of progressive supranuclear palsy

Background and purpose Progressive supranuclear palsy (PSP) can occur with two main clinical presentations, classified as classical Richardson's syndrome (PSP‐RS) and as PSP‐parkinsonism (PSP‐P), the most common atypical PSP variant. The differential diagnosis between them is challenging. Therefore, we studied different ultrasound markers by transcranial sonography in individuals with PSP‐RS and PSP‐P, to test their value in the diagnostic work up of these patients. Methods Transcranial sonography was performed in 21 patients with PSP‐RS and 11 patients with PSP‐P. Echogenic sizes of the substantia nigra (SN) and the lenticular nuclei (LN), as well as the width of the third ventricle, were measured. Results Among the patients with PSP‐RS and PSP‐P, three (14%) and eight (73%) patients had a hyperechogenic SN (P = 0.020), respectively. Uni‐ or bilateral hyperechogenicity of the LN was observed in 67% and 36% of patients with PSP‐RS and PSP‐P, respectively (P = 0.101). Third ventricle was significantly wider in patients with PSP‐RS (11.2 ± 2.3 mm) when compared with patients with PSP‐P (7.5 ± 1.4 mm; P = 0.001). Conclusion Our data, possibly reflecting pathological differences, primarily contribute supporting the view that the neurodegenerative process differs in the two PSP variants.