Transcranial sonography on Parkinson’s disease and essential tremor in a Chinese population

Abstract

We analyzed the results of transcranial sonography (TCS) on 110 Parkinson's disease (PD) patients, 30 essential tremor (ET) patients and 110 controls in a Chinese population and compared our findings to the previous literatures. The echo signal intensity of midbrain substantia nigra (SN) was measured and divided into grade I-V. If the high echo signal intensity (grade III, IV or V) was detected in either side of SN, it was measured as well as the whole area of midbrain and the ratio of both sides of SN hyperechogenicity to the whole area of midbrain (S/M) were calculated. In addition, the width of the third ventricle in the level of thalamus was also determined. There were more individuals with the grade of SN ≥ III in PD group (100/110, 85.45%) than these in ET group (4/30, 13.33%, x ( 2 ) = 58.38, P < 0.001) and control group (11/110, 10%, x ( 2 ) = 125.51, P < 0.001). The median and quartile range of SN hyperechogenicity area and S/M in PD patients were greater than those in ET patients and controls. Both the area of SN hyperechogenicity ≥0.2 cm(2) and the S/M ≥ 0.07 were useful indexes to distinguish PD and ET in Chinese population. In conclusion, TCS is an effective and useful tool to detect PD and to distinguish PD from ET in Chinese patients.

Increased substantia nigra echogenicity correlated with visual hallucinations in Parkinson’s disease: a Chinese population-based study

“…The cutoff value in our study is higher compared with other researches [8,38,39]. To investigate the reason for this phenomenon, Table 3 demonstrates the clinical features of our study and 5 other studies [7,8,[38][39][40]. The mean age was calculated using the information from all the participants, while the disease duration and H-Y stage were from only the PD patients.…”

Alteration of brainstem raphe measured by transcranial sonography in depression patients with or without Parkinson’s disease

“…The occurrence of an abnormal substantia nigra could increase with increasing age, especially because it is present in 10 % of individuals more than 60 years old [7,8].…”

“…As a neuroimaging technology, transcranial sonography (TCS) can show the enlarged area of increased echogenicity in substantia nigra compared to the surrounding tissue in PD [5][6][7][8][9]. TCS has also been used to show structural alteration of the mesencephalic brainstem raphe (BR) nucleus in depression patients.…”

How to Measure Substantia Nigra Hyperechogenicity in Parkinson Disease

“…High intra‐ and inter‐rater reliability and diagnostic accuracy of planimetric substantia nigra echogenicity measurements have been demonstrated by numerous groups 7 , 14 , 20 , 22 , 26 – 28 , 35 – 38 . Another group reported less favorable reliability; however, no transcranial sonograms were presented in their publications 39 , 40 .…”

“…2,3 High intra-and inter-rater reliability and diagnostic accuracy of planimetric substantia nigra echogenicity measurements have been demonstrated by numerous groups. 7,14,20,22,[26][27][28][35][36][37][38] Another group reported less favorable reliability; however, no transcranial sonograms were presented in their publications. 39,40 A number of investigator-and laboratory-related pitfalls can impair the reliability of transcranial sonography and need to be excluded before diagnostic application (Table 2).…”