203 years ago, a British doctor published an article entitled Research on Paralysis Agitans, which detailed 6 patients he ever met with such symptoms as severe tremor and postural instability. He couldn't have imagined that this was the first case of Parkinson's disease that had been systematically recorded in history. The name of the doctor was James Parkinson. Such disease he described was named after him, and his birthday April 11 was also designated as the World Parkinson's Disease Day.
Parkinson's disease is a common neurodegenerative disease, with symptoms including resting tremor and bradykinesia, which is often accompanied by mental disorders such as dementia. Although it is not lethal, it will greatly impact the patient’s life.
At present, there is no specific treatment for Parkinson's disease yet, and early detection and timely intervention are of crucial importance. However, early diagnosis of Parkinson's disease is no easy task. Parkinson's disease was also known as a “silent killer” since its symptoms at the early stage are not obvious, and it is easy to be ignored or misdiagnosed. However, when the typical symptoms appear, it is already too late.
To this end, research on diagnosis of Parkinson's disease at early stage has been strengthened in the medical field in recent years, among which, transcranial ultrasound has emerged as a new diagnostic method with prominent effects. In 2013, the European Federation of Neurological Societies Guidelines stated that transcranial ultrasound could be used for the diagnosis of early Parkinson's disease; in 2016, the Diagnostic Criteria for Parkinson's Disease in China also pointed out that abnormal substantia nigra echoes could help distinguish Parkinson's disease from Parkinsonian-plus syndrome.
For the transcranial ultrasound examination for Parkinson's disease, the probe is attached to the temporal window on one side of the patient’s skull for scanning to observe the midbrain horizontal section, and it can be seen that the midbrain is butterfly-shaped; then a further observation of the intensity and area of substantia nigra (SN) echo is conducted, if the high echo area of the SN is more than 0.20 cm², or the total area of the high echo of SN on both sides/ total area of midbrain is no less than 7%, it can be judged as a positive SN ultrasound, which can be used as one of the bases for diagnosis of Parkinson's disease.
In addition, studies have demonstrated that the detection of the width of the third ventricle and the width of the frontal angle by transcranial ultrasound also comes as a good diagnostic method for judging whether Parkinson's disease is accompanied by dementia.
The use of transcranial ultrasound for diagnosis of Parkinson's disease has many advantages in clinical applications. Transcranial ultrasound method shows the abnormal high echo area of the midbrain SN clearly, while it is difficult for MRI and CT to show the structural changes accurately. In addition, the transcranial ultrasound also features such advantages as non-invasiveness, repeatability, no radiation damage, real-time display and low cost, etc.
However, the application of transcranial ultrasound is not completely unconditional. First, the subject (the person to be tested) needs to have a bone window with good ultrasound penetration. Secondly, the performance requirements of the ultrasound equipment are high. Taking VINNO as an example, VINNO G80, VINNO M80, and VINNO M86 three series of high-end color Doppler ultrasound equipment can support transcranial ultrasound applications well. Xcen technology possesses better bone window penetration, high precision polar beam imaging technology can achieve good midbrain image presentation.
VINNO M86 VINNO M80 VINNO G80
In 2019, the Second Affiliated Hospital of Soochow University chose VINNO G80 for the transcranial ultrasound research project. During this period, VINNO G80 assisted the scientific research experts in performing transcranial ultrasound testing on nearly 100 patients. Reliable data and image basis are recognized by experts.
It is reported that China has about 2.50 - 3.00 million patients with Parkinson’s disease, accounting for about 50% of the world; however, there are only more than 1,000 specialist doctors in China. In the face of such a dilemma, the use of transcranial ultrasound for efficient diagnosis comes as a powerful countermeasure to make breakthroughs, and there is no denying that ultrasound technology has much to offer in the diagnosis and treatment of Parkinson's disease in the future.