These hard technologies make medical imaging more precise | equipment | medical

Health Frontiers

The world's first full body 5.0T magnetic resonance imaging of the human body has been released, and China has taken the lead in achieving ultra high field high-resolution full body clinical universal imaging; The first domestic extracorporeal membrane oxygenation system was registered and certified, which filled the long-term gap in China at one fell swoop, and solved the "urgent need" of treating COVID-19 severe patients; The world's first non-invasive magnetic resonance guided ultrasound radiation force deep brain nerve regulation instrument has been successfully developed, allowing ultrasound to connect with neuroscience and providing a new technology and means for the treatment of complex functional brain diseases

In recent years, China's ability to independently innovate in science and technology has continued to improve, from following and running to leading, from assembling components to mastering core technologies. High end medical equipment with completely independent intellectual property rights has emerged, breaking through key core technologies and breaking foreign monopolies.

1. Develop high-end magnetic resonance equipment for Chinese people themselves

"Time goes back to just 10 years ago, when the high-end medical imaging equipment market in China was monopolized by overseas international medical equipment giants. Due to China's lack of core technology and technological constraints, domestic magnetic resonance equipment was mainly distributed in the mid to low end market, and high-end 3.0T magnetic resonance equipment relied 100% on imports." Li Ye, Deputy Director and Researcher of the Medical Engineering Institute of Shenzhen Advanced Hospital of the Chinese Academy of Sciences, recalled that 10 years ago, he joined the Shenzhen Advanced Technology Research Institute of the Chinese Academy of Sciences to work with the team here to independently develop high-end magnetic resonance equipment for the Chinese people.

According to Li Ye's recollection, more than a decade ago, even mid-range magnetic resonance imaging devices like 1.5T had a very low market share in domestic products. "High end medical imaging equipment has long relied on imports, with high import prices and high costs for patients to undergo relevant examinations. China is a populous country, and it is difficult to imagine that 1.4 billion people rely on imported equipment from abroad to seek medical treatment. Whether from an economic or clinical diagnostic perspective, people have always been looking forward to high-performance domestically produced equipment." Li Ye introduced that magnetic resonance signals are an electromagnetic wave, and magnetic resonance equipment is a very powerful imaging tool for clinical medical diagnosis. Its advantage is that it can perform high contrast multi parameter imaging of various parts of the body, and there is no ionizing radiation. This is another imaging technology revolution after CT. Magnetic resonance imaging larger than 3.0T is called ultra-high field magnetic resonance. The higher the magnetic resonance field strength, the higher the image resolution, and the more precise the medical imaging examination. Of course, it also poses greater technical challenges to the equipment.

Starting from scratch, challenges can be imagined. At that time, multinational giants had been occupying the high-end medical imaging equipment market for decades, and their accumulated technology "moat" was unattainable. In order to break through the core technology as soon as possible, the team worked tirelessly day and night. When asked about the hardships of the research and development process, Li Ye said there was nothing particularly worth mentioning. Anyway, "It's common to do experiments until one or two in the morning. If an experiment fails, summarize the experience and start over. If it succeeds, continue to move forward, knowing in your heart that you will definitely succeed in the end."

Ten years have passed, and things have been done like this. In November 2021, a team from the Shenzhen Advanced Institute of the Chinese Academy of Sciences collaborated with Lianying Medical and others to complete the "Independent Development and Industrialization of High Field Magnetic Resonance Medical Imaging Equipment" project, which won the first prize of the National Science and Technology Progress Award, achieving a major breakthrough in independent innovation of high-end medical equipment in China. "Last August, the world's first Lianying 5.0T ultra-high field human whole body magnetic resonance imaging system was approved for national medical device registration. This is the world's first clinical universal device for human whole body 5.0T high-resolution magnetic resonance imaging. Among them, we have solved scientific problems, broken through core technologies, and achieved international leadership." Li Ye said.

Liang Dong, Director and Researcher of the Medical Engineering Institute of Shenzhen Advanced Hospital, has been focusing on the development of fast imaging technology in magnetic resonance systems for a long time. He introduced that the 3.0T magnetic resonance equipment has two important characteristics: firstly, all core components are independently developed and no imported components are used, breaking through the bottleneck problem; The second is the rapid imaging technology that combines software and hardware. "If you have undergone medical imaging examinations in a hospital, you will find that magnetic resonance imaging takes much longer than CT examinations. It takes about 20-30 minutes to perform one examination, and a device can only examine 20-30 patients per day. Due to the large number of patients, it is common to wait for three to four weeks to schedule a magnetic resonance imaging examination." Liang Dong said that in order to avoid delaying treatment, it is necessary to develop high-end magnetic resonance imaging equipment that can be produced abroad and quickly imaged.

What does fast imaging speed mean? "Simply put, the previous equipment used to take photos, but now we can use this equipment to make movies." Liang Dong explained, "Because the imaging speed is fast enough, doctors can see more things that they couldn't see before during examinations. Moreover, the examination time for each patient has been shortened, so one device can complete the examination volume of the previous two devices. Taking stroke examination of the cerebral vascular wall as an example, this is an examination that requires high resolution and takes a long imaging time. In the past, it took about fifteen minutes to do this examination, but now using a 5.0T magnetic resonance imaging device to do sub millimeter high-resolution examination only takes about three and a half minutes. The implementation of such excellent fast high-resolution imaging relies on its background." The invention and system support of new system magnetic resonance imaging technology, "said Liang Dong.

As the first global user of 5.0T ultra-high field magnetic resonance imaging, Wang Yining, the chief physician of the Radiology Department at Peking Union Medical College Hospital, told reporters about a case where he once treated a 44 year old female patient with sudden limb weakness. From the 5.0T cranial imaging, cerebral hemorrhage and ischemia can be seen. What is the reason for this? "Through 5.0T vascular imaging, it was found that the middle cerebral artery presented a dual lumen structure. We considered that she had arterial dissection, so we performed a gold standard angiography and found that there was indeed arterial dissection with torn intima. This patient had also undergone a 3.0T examination before, but due to insufficient resolution, no issues with cerebral blood vessels were detected. Therefore, 5.0T high-resolution vascular imaging can help us identify the cause and diagnose and treat it earlier," said Wang Yining.

When the reporter and his team visited the Lianying 5.0T magnetic resonance equipment at Shenzhen Advanced Hospital, researchers were anesthetizing a monkey and pushing it into the equipment. This was an image guided neural regulation related experiment, exploring the higher value of this high-end magnetic resonance equipment in the field of neural regulation therapy.

2. Improve cure rate and reduce patient burden

The Shenzhen Advanced Institute of the Chinese Academy of Sciences can be regarded as the "national team" for innovative development of high-end medical equipment. In the medical imaging laboratory of the institute, rows of control lights on a high-precision instrument flicker alternately. The manipulation sound field formed by over 10000 probes emitting ultrasonic waves is like the "hand of God" passing through the skull of experimental animals, reaching deep into the brain, accurately "touching" some neurons, producing subtle deformations of only a few micrometers, which are keenly captured by magnetic resonance imaging machines.

This is a deep brain stimulation and neural regulation instrument based on ultrasound radiation force developed by the team led by Zheng Hairong, Vice President of Shenzhen Advanced Institute of Chinese Academy of Sciences. "This instrument allows ultrasound to 'hold hands' with neurons and use ultrasound to manipulate neuronal activity, effectively regulating the deep brain in a non-invasive and precise manner. This is of great help for the precise diagnosis and treatment of brain diseases such as Parkinson's disease, Alzheimer's disease, depression, and epilepsy." Zheng Hairong introduced that the device has now entered the clinical trial and industrialization stage.

Ultrasound is a mechanical wave that utilizes the scattering of waves in human tissues for imaging, commonly known as B-ultrasound and color ultrasound. Decades ago, scientists observed that ultrasound can cause tiny particles in the sound field to move. Based on the theory of acoustic tweezers and the research of acoustic radiation force technology, Zheng Hairong's team not only allows ultrasound to hold hands with neuroscience, but also develops ultrasound elastography equipment to assist in precise clinical diagnosis and early diagnosis.

"Our traditional B ultrasound color ultrasound uses the wave effect of ultrasound to see the changes in the organizational structure, but in the early stage of many diseases, its organizational structure may not change significantly, but there are some changes in hardness and softness, such as liver fibrosis and cirrhosis, which have a high incidence rate in China, and breast cancer, which has a high incidence rate in women." Zheng Hairong gave an example to introduce that when judging the benign and malignant of breast cancer tumors, in the general B ultrasound, its shape is a tumor, but the main difference is that the soft and hard are different. In the past, doctors usually had to rely on puncture biopsy to distinguish. Now with non-invasive ultrasound elastography equipment, doctors can use ultrasound mechanical effects to observe the softness and hardness of human tissue, and achieve non-invasive quantitative measurement of biomechanical parameters of human tissue. "Generally speaking, doctors can use this device to more accurately and conveniently judge whether early breast cancer is benign or malignant," Zheng Hairong concluded.

Liang Dong introduced that currently, in addition to structural imaging devices such as ultrasound, magnetic resonance imaging, and CT, molecular imaging devices are also assisting clinical practice in precise diagnosis and treatment, especially in early diagnosis.

"The imaging resolution of structural imaging devices such as magnetic resonance imaging and CT is getting higher and higher, and doctors can use these devices to find small lesions that were previously invisible. However, from an early diagnostic perspective, many diseases may not necessarily have structural changes in the early stages, and even with fine examination, doctors cannot make a clear diagnosis. Many diseases may experience metabolic and functional changes in tissues and organs in the early stages, such as degenerative diseases like Alzheimer's disease. In fact, patients have already experienced changes in the metabolic activity of nerve cells long before the brain shrinks. Therefore, molecular imaging devices that measure functional metabolic changes are particularly important in early diagnosis." said Yang Yongfeng, a researcher at the Institute of Medical Engineering at the Shenzhen Advanced Hospital of the Chinese Academy of Sciences.

Regarding early diagnosis, Yang Yongfeng introduced his leading research and development of the first high-definition magnetic resonance compatible PET functional imaging device for the human brain in China. What is the imaging principle of PET equipment? "We first inject drugs labeled with radioactive isotopes, such as glucose drugs, into the human body. After injection, the drugs will be metabolized in the body. Because cancer cells are generally more active and metabolize more sugar, the drugs we inject will gather here, and the drugs will decay through radiation. At this time, we can use PET detectors to measure the location and quantity of radioactive drug decay, and then know whether the person has cancer, where it is, the severity, and whether there is metastasis." Yang Yongfeng introduced that PET devices have obvious advantages in the early diagnosis of many diseases, such as Alzheimer's disease. Current research has found that PET devices combined with appropriate drugs can detect the appearance of the disease. "Diagnose it 15 years before the symptoms. For many diseases, if an early diagnosis can be made, doctors can intervene in advance, and patients do not have to wait until the late stage of the disease to spend high medical costs for treatment. This can not only reduce the pain and burden of patients, but also delay the development of the disease and improve the cure rate," said Yang Yongfeng.

3. How to develop high-end medical equipment in the future

Speaking of his experience in developing medical imaging equipment in recent years, Zheng Hairong summarized that he should carry out organized scientific research with strong goal orientation, break down innovation silos between disciplines, and build a collaborative innovation platform for industry, academia, research, and medicine.

"We have close cooperation with medical equipment companies and clinical hospitals. Based on the disciplinary characteristics of this instrument research and development field, we have also opened up corresponding 'special zones' for scientific researchers, allowing most technical personnel to only calmly consider scientific research difficulties without worrying about applying for research projects or writing papers. For example, as long as effective breakthroughs are made in technology and core technologies are mastered, promotion and recognition can be obtained without the need for research projects, papers, or hats. Under such a mechanism, many of our scientific researchers will set their minds to cooperate with enterprises, and scientists and engineers achieve' seamless integration '. Together with the engineering team, they work together to solve technical problems and achieve true integration and collaborative innovation between production and research." Zheng Hairong introduced.

"Good medical equipment is made and used," Zheng Hairong firmly believes in this. "So, the R&D team of high-end medical equipment should avoid talking about it on paper, write research results on the land of our country, target national needs, grasp clinical pain points, and develop medical equipment with clinical value. After the transformation of scientific and technological achievements, they should also timely connect with hospitals, and further improve and iterate through clinical feedback."

In Zheng Hairong's view, the goal of developing high-end medical equipment in the future is clear. "The goal of medical equipment research is to serve people's health, and the future direction of scientific research is to diagnose and treat more accurately." Zheng Hairong said that to achieve this goal, the medical research and development team must first focus on the classic field of diagnostic and treatment equipment, and develop advanced equipment that is "urgently needed in clinical practice and has significant support for medical treatment, such as multimodal high-resolution medical imaging equipment, functional imaging equipment, and large-scale proton therapy equipment for tumor treatment."

Regarding research on tumor treatment, Professor Xu Yingxin, former Deputy Director of the Institute of General Surgery at the General Hospital of the People's Liberation Army of China and a specially appointed expert in national health products, introduced that the reason why tumor treatment is comprehensive and very complex is because various existing treatment methods have their limitations. "For example, CAR-T has achieved good therapeutic effects in treating B-cell-derived tumors, but at the same time, it kills normal B lymphocytes, often requiring stem cell transplantation."

"At present, we are strengthening the basic and clinical application research of stem cells and immune cells. In the future, we will combine surgery, immune cell therapy, and stem cell transplantation technologies to develop different treatment plans according to the specific conditions of different patients." Xu Yingxin said.

In addition, for emerging revolutionary technologies that cannot be fully understood at present, active layout should also be made. Artificial intelligence, nanotechnology, high-temperature superconductivity, quantum technology at the forefront of physics, etc., these cutting-edge technologies may have more interdisciplinary fields with medicine in the future, nurturing new instrument technology changes. For example, it has been found that tumors also have weak quantum signals, and magnetic resonance equipment signals are derived from quantum effects. However, now we are using their macroscopic quantum signals. So, can we develop microscopic magnetic resonance imaging in the future, and can we develop extremely weak quantum magnetic resonance imaging diagnostic equipment? That may be a new weapon for tumor and brain disease examination. I think this is the development direction of high-end medical equipment worth paying attention to in the future. In short, as long as it is... "The demand for scientific discovery and precise clinical diagnosis and treatment are both worth cultivating. I think this is also the dream of the medical instrument development team," Zheng Hairong sighed.