The mesencephalic nucleus of substantia nigra (SN) was examined by means of transcranial color-coded sonography (TCCS) in 15 patients suffering from Parkinson’s disease and in 14 healthy volunteers. Two devices were used for the investigations: ESAOTE AU4 with a probe of 2.5 MHz, and ATL HDI 5000 with a probe of 2–3 MHz. On the base of published data, there was created a semiquantitative scale of echogenity within the range of arbitrary values of 1–5, when echogenity 5 was the highest value found out by our examinations. The scale is comparing the SN echogenity with that of the brain stem and of basal cisterns when the brain stem is anechogenic (stage 1), basal cisterns are hyperechogenic (stage 4). The increased SN echogenity was revealed in 13 patients with Parkinson’s disease, the decreased SN echogenity was present in 2 patients. The elevated SN echogenity was found out only in one healthy volunteer. Our pilot study has shown that hyperechogenic SN is well detected in patients with PD and, on the contrary, hypoechogenic SN is found nearly exceptionally in subjects without PD. The abnormal SN echogenity in patients with PD is probably caused by a not quite elucidated re-building of a nucleus during the decline of nigral neurons. Our results are in correlation with the data from recent pilot studies carried out in abroad, and TCCS examination seems to be a possible contribution for non-invasive differential diagnostics of Parkinson’s disease. However, this must be further verified in larger sets of patients, namely in correlation with other methods.

        Key words: ultrasound of the brain stem, Parkinson’s disease, substantia nigra