PET-CT
PET-CT integrates CT and PET. CT provides precise anatomical positioning of the lesion, while PET provides detailed molecular information such as function and metabolism of the lesion. It has the characteristics of sensitivity, accuracy, specificity and precise positioning. It can obtain tomographic images from all directions of the whole body in one imaging, and can understand the overall condition of the whole body at a glance, so as to achieve the purpose of early detection of lesions and diagnosis of diseases. The emergence of PET-CT is another revolution in medical imaging, which has been recognized and widely concerned by the medical community.
PET/CT is currently the world's most high-end medical imaging diagnostic equipment, and can be called "the crown of modern medical high technology."
PET (Positron Emission Computed Tomography, PET) stands for positron emission computed tomography. It is the most advanced medical imaging technology. PET technology is currently the only technology that uses anatomical morphology to perform functional, metabolic and receptor imaging, and is non-invasive. It is one of the best methods currently used clinically to diagnose and guide the treatment of tumors.
The unique function of PET is based on metabolic imaging and quantitative analysis. It uses short-lived nuclides that make up the main elements of the human body, such as 11C, 13N, 15O, 18F and other positron nuclides as tracers. It not only Multi-slice tomographic images, three-dimensional quantitative results and three-dimensional whole-body scans can be quickly obtained, and the physiological and biochemical changes of metabolites or drugs in the human body can be dynamically observed from the molecular level to study human physiology, biochemistry, chemical transmitters, Receptors and even genes change. In recent years, PET has shown unique advantages in diagnosing and guiding the treatment of tumors, coronary heart disease, and brain diseases.
PET/CT organically combines PET and CT (computed tomography), using the same examination bed and the same image processing workstation to fuse PET images and CT images, allowing simultaneous Screening the pathophysiological changes and morphological structure of the lesions can significantly improve the accuracy of diagnosis.
1. PET-CT can perform early diagnosis and differential diagnosis of tumors, identify tumor recurrence, stage and restage tumors, find primary tumors and metastases, and guide and determine tumor treatment. Plan and evaluate efficacy. Among tumor patients, a considerable number of patients have changed their treatment plans after PET-CT examination because of a clear diagnosis; PET-CT can accurately evaluate the efficacy, adjust the treatment plan in a timely manner, and avoid ineffective treatment. Overall, medical expenses are greatly saved and valuable treatment time is saved.
2. PET-CT can accurately locate epileptic lesions and is also a unique examination method for diagnosing depression, Parkinson's disease, Alzheimer's disease and other diseases. The treatment of epilepsy is one of the top ten medical problems in the world. The difficulty lies in the accurate location of the epileptogenic focus. PET-CT can easily solve this medical problem. Under the guidance of PET-CT, X-knife or γ-knife treatment was used, and good therapeutic effects were achieved.
3. PET-CT can identify whether the myocardium is viable and provide objective basis for whether surgery is needed. Currently, PET-CT myocardial imaging is recognized as the “gold standard” for estimating myocardial viability. It is a necessary examination before myocardial infarction revascularization (revascularization) and other treatments, and provides a basis for radiotherapy evaluation. PET-CT is also of great value in the diagnosis of early coronary heart disease.
4. PET-CT is also a means of health examination. It can complete the whole body examination in one imaging, and can early detect tumors and heart and brain diseases that seriously endanger people's health, so as to achieve early treatment of diseases. disease prevention purposes.
Modern medicine believes that most diseases are the result of imbalance of biochemical processes in the body. PET-CT can dynamically and quantitatively observe biochemical changes at the molecular level in the body under physiological conditions. With the decryption of human genes, the occurrence, development and treatment outcomes of tumors, heart and brain diseases, and various hereditary diseases that endanger human health will be fundamentally understood, and it is also expected to find fundamentally effective treatments. Treatment options.
PET-CT gene imaging is a "bridge" connecting clinical and basic genetic research.
The following is the Chinese translation of the JNM article recommended by Professor He Zuoxiang of Fuwai: Journal of Nuclear Medicine Vol. 46 No. 3 385
Written by James W. Fletcher, MD Fang Tingzhengyi There is no doubt that the era of PET/CT has arrived. At present, at least 3 of every 4 ECT machines sold are PET/CT featuring hardware fusion. However, since the early 1990s when PET examinations based on 18F-FDG imaging began to be put into routine commercial operation in clinical practice, the development of PET technology has been tightly controlled in the hands of the nuclear medicine industry and no one from other fields has interfered. . In the past 5 years, PET technology, including PET/CT commercial manufacturing, has developed rapidly. The advantage of PET/CT over dedicated PET comes from the perfect combination of two imaging technologies that provide structural information and functional information respectively. These advantages and the resulting improvement in the ability to locate and characterize diseases have now been grasped by a broad range of medical professionals far larger than the nuclear medicine community. In this case certain members of the nuclear medicine community - specialized physicians - may be in danger of becoming obsolete. The reason is obvious. Just as PET/CT will replace dedicated PET on a large scale, PET/CT equipped with diagnostic-grade CT that can use oral and interventional enhancers and has higher electrical power will also replace single CT. Since many nuclear medicine physicians are not proficient in CT cross-sectional anatomy, they are currently unable to professionally interpret CT information in PET/CT. And if PET/CT examination only needs to stay at the primary level of using its CT part for attenuation correction and lesion localization in 18F-FDG PET imaging, then there is no need to conduct diagnostic-level CT examinations, and there is no need to analyze CT information. Perform a formal interpretation. For radiologists who are not well versed in PET imaging, they are facing the exact opposite problem, and some have argued that PET and CT should be interpreted separately by physicians qualified in their respective fields. However, in the long run, this suggestion does not solve the problem. In order to ensure that patients undergoing PET/CT examinations receive the best treatment, the physicians who perform this work must be equally proficient in both PET and CT. The highest level of this comprehensive work requires physicians to use diagnostic-grade CT imaging information together with PET imaging information to diagnose patients. This goal can only be accomplished by professionals who have received rigorous training and reached a considerable level in both fields. Unfortunately, current academic education in nuclear medicine and radiology is unrelated and does not provide the experience and training required to achieve the above professional standards. This lack of curriculum prevents both patients and the professional community from achieving the goals they expect.
Correcting this situation requires starting from two levels. At the academic level, there must be courses of sufficient length and coverage to enable residents to receive education and training in both tomography and PET. At the clinical practice level, there must be adequate and well-mixed continuing education and experience learning to enable practitioners to achieve the same high level of diagnostic, interpretive, and comprehensive abilities in both areas. For residents, it is necessary to evaluate and adjust the level of training and experience provided by school courses in order to meet the requirements of PET and CT education in the new situation. For clinicians, it is necessary for relevant professional associations to discuss and establish specific measures for continuing education and experience summarization. These measures will improve and professionalize the qualifications of PET/CT clinical practitioners and gain widespread recognition and respect. . These measures and approaches are being put into action, which will surely be a victory for the nuclear medicine community and good news for patients.
PET-CT is by no means a panacea, but it is definitely a revolutionary breakthrough in imaging technology. It will play an increasingly important role in the clinical diagnosis and treatment of tumors!
Medical prospects
In recent years, the number of PET/CT machines in our country has increased rapidly. According to surveys, 54 PET/CT machines were installed by the end of August 2006. The current problems are: The development of various regions is unbalanced and the preparation is unreasonable; there is a lack of examination guidelines and diagnosis and treatment standards for PET/CT; there is a lack of innovation in scientific research, a lack of multi-center research results, a lack of summary reports on large numbers of cases, and research on health economics evaluation has just started; There is an obvious shortage of talents in comprehensive imaging and radiopharmaceuticals, and the urgent need can be solved through continuing education.
PET/CT is mainly used for malignant tumors, and malignant tumors have become the main killer of people's health in our country. It is not uncommon for families to become poor because their relatives suffer from tumors. The actual situation is: Although the high-end equipment PET/CT is very helpful in the diagnosis and treatment of patients, a considerable number of patients have to give up using it because they cannot afford the expensive examination fees. For this reason, except for a few of the above-mentioned 54 centers, it is difficult for a center to perform more than 1,500 examinations throughout the year, resulting in most PET/CT and accelerators not functioning. It can be expected that as the application of PET/CT gradually matures, the clinical value of PET/CT will definitely be recognized. Once the examination fees for some diseases (such as certain malignant tumors) are included in medical insurance, the demand for PET/CT examinations will increase. The dosage will increase significantly and it will play a greater clinical role.