Positron emission computed tomography (PET/CT)

Method

Positron emission computed tomography (PET/CT) is a radionuclide tomographic method for the study of internal human organs. The method is based on the registration of a pair of gamma quanta that occur during annihilation of positrons with electrons. Pozitrons occur during the beta decay of radionuclide, which is part of the radiopharmaceutical, which is intravenously injected into the body before the study and selectively accumulated in tumor tissues.

Differences in imaging methods on the example of the brain

This method is based on the ability, using special detection equipment (PET scanner), to track the distribution in the body of biologically active compounds labeled with positron-emitting radioisotopes. To date, PET mainly uses positron-emitting isotopes of elements of the second period of the periodic system, most often fluorine-18, which has optimal characteristics for use in PET: a short half-life and the least radiation energy.

Most often, for positron emission tomography, a biological analogue of glucose is used - fluorodeoxyglucose (FDG), the molecule of which contains radioactive (positron-emitting) nuclide fluorine-18 (18-FDG). FDG is administered to the patient, after which it is distributed throughout the body. Tumor cells consume glucose much more intensively than others, this allows you to register areas of drug accumulation (FDG) using a PET scanner - clusters of tumor cells.

The use of a radiopharmaceutical requires the organization of a full-fledged production - a cyclotron complex in the immediate vicinity of a medical institution. To obtain fluorine-18, a cyclic accelerator such as a medical cyclotron, less often a linear accelerator, is used. The target is usually pure or oxygen-enriched-18 water that is proton bombarded. Oxygen-18, in turn, is obtained by the method of low-temperature rectification.

There are already similar PET centers in Russia, for example, in Moscow, St. Petersburg, Khabarovsk, Khanty-Mansiysk, Kazan. At the beginning of 2019, there are about thirty such operating centers with their own production in Russia.

How does a PET scanner differ from a gamma camera?

PET scanners and gamma cameras (scintigraphy machines) are nuclear diagnostic installations that are considered the most accurate in oncology, cardiology and neurosurgery. How are they different? The principle of operation is approximately the same: the patient is injected with a radiopharmaceutical (RMP), which accumulates in a certain organ or tissue and emits weak energy quanta, and the diagnostic installation captures this radiation and forms images. Thanks to the short half-life, the FPM is quickly removed from the body (from several hours to two days) and does not harm the patient, so you should not be afraid of radiation. The dose of radiation received during one examination is ten times less than the dose received after the image on the X-ray apparatus.

The difference between PET and gamma camera is the number of images. PET forms a 3D volumetric image of the area under study, and the gamma camera forms only given projections. I.e. PET (which is usually combined with CT) gives a more accurate picture. But the equipment of the gamma camera is cheaper and easier to install/launch. Therefore, gamma cameras are more common. However, according to 2009 data, 80% of those 200 gamma cameras installed in Russia are already morally and physically outdated. For comparison, in the United States at that time, more than 12 thousand gamma cameras functioned and annually more than 15 million patients undergo scintigraphy on them.

Chronicle of the development of technology

2025

Russian physicists have made a quantum breakthrough in PET diagnostics: Scanners will be able to "see" invisible tumors

Russian physicists from the Moscow Institute of Physics and Technology, together with colleagues from the Institute for Nuclear Research of the Russian Academy of Sciences, made a revolutionary discovery in the field of quantum physics, which will radically change the diagnosis of cancer using positron emission tomography. Scientists have proven that quantum entanglement between gamma photons persists even after they scatter in the tissues of the human body, researchers said in July 2025.

The discovery concerns one of the most modern methods for diagnosing cancer and Alzheimer's disease - positron emission tomography. Until now, it was believed that photons subjected to Compton scattering when passing through body tissues lose their quantum properties and become a source of noise that degrades image quality.

𝓲

Фото: Freepik

Medical specialists traditionally filtered such signals, considering them useless for diagnostic purposes. Scattered radiation was seen as an obstacle that reduces the accuracy of the resulting images and makes it difficult to detect pathological changes in the body.

Experiments by Russian scientists have demonstrated opposite results. Even after significant scattering, the photons retain quantum entanglement with their paired particles. This means that information that was previously considered unsuitable and excluded from analysis actually contains valuable data on the location of tumor cells.

The results of the study are published in the authoritative scientific journal Scientific Reports and have been confirmed in independent experiments by British colleagues from the University of York. International recognition of the discovery confirms its scientific significance and potential for practical application.^[1]

Quantum entanglement could improve cancer diagnosis

Scientists at the Moscow Institute of Physics and Technology (MIPT), together with the Institute for Nuclear Research of the Russian Academy of Sciences, received unexpected results regarding the preservation of quantum entanglement in Compton photon scattering. The obtained data can seriously affect the development of technologies in medical imaging, in particular, positron emission tomography. MIPT announced this on July 1, 2025.

𝓲

Фото: MIPT

Quantum entanglement is one of the most surprising properties of quantum theory. This is the ability to maintain superposition (being in several states at the same time) of quantum states at macro-distances. This effect was first experimentally investigated 70 years ago in a system of two photons formed by annihilation (mutual destruction in collision) of positrons and electrons. It was previously believed that the interaction of photons with the environment leads to a loss of entanglement, however, new research has shown that this is not the case.

According to the results that we obtained at the installation at the INR RAS, quantum entanglement remains almost completely even at significant scattering angles. This discovery casts doubt on existing ideas about the interaction of photons and opens up new opportunities for creating new generation positron emission tomographs (PETs), "said Sultan Mussin, one of the authors of the study, assistant of the Department of General Physics at MIPT.

A positron emission tomograph (PET) is a medical tool for visualizing metabolic processes in the body. It uses radiopharmaceuticals labeled with positrons, which accumulate in active tissues such as tumors. During annihilation of positrons and electrons, gamma rays occur, which are recorded by the scanner.

In PET machines, it is important to accurately determine the location of the tumor by registering pairs of photons that occur during the annihilation process. However, scattering these photons when interacting with surrounding tissues distorts the data, creating noise and reducing image clarity. The studies conducted call into question the reliability of using polarization correlations to filter these noises.

It was initially suggested that differences in polarization between initial and scattered photons could improve imaging quality, but the experiments performed did not confirm this. Scientists found no expected differences in polarization correlations. In their opinion, this makes the current approach to creating quantum tomographs based on polarization impractical.

Our results showed that the entangled states of annihilation photons do not collapse to separable as previously thought. This discovery not only changes ideas about quantum entanglement, but also poses a challenge for the further development of quantum technologies in the field of medical imaging, Sultan Mussin added.

The discovered effects pave the way for new approaches in quantum technology using the transmission of entangled photon states, scientists say, and may lead to more effective medical diagnostic techniques in the future.

2024

The volume of the global market for PET scanners for detecting cancer for the year reached $11.74 billion

In 2024, the costs of the global positron emission tomography (PET) market for detecting malignancies reached $11.74 billion. More than half of global spending was in the North American region. Such data are contained in a Fortune Business Insights study, the results of which were published on July 31, 2025.

PET is a painless, non-invasive imaging technique that is used to diagnose serious diseases early, including cancer. The method is based on the registration of a pair of gamma quanta that occur during annihilation of positrons with electrons. To detect pathological processes, radiopharmaceuticals are used, which are introduced into the body before scanning. The key advantages of PET diagnostics are the high reliability of the results, the ability to detect tumors at the asymptomatic stage, the absence of age restrictions and safety.

𝓲

Фото: Freepik

One of the main drivers of the market is the increase in the prevalence of cancer. According to the World Health Organization (WHO), in 2022, approximately 20 million new cases of cancer and 9.7 million deaths caused by it were registered. Lung cancer is the main cause of death from malignancies on a global scale: it accounted for 1.8 million deaths in 2022, or 18.7% of the total. Next come colorectal cancer (900 thousand deaths, 9.3%), liver cancer (760 thousand deaths, 7.8%), breast cancer (670 thousand deaths, 6.9%) and stomach cancer (660 thousand deaths, 6.8%). Despite the progress made in early cancer detection, treatment and care of cancer patients, significant differences in therapy outcomes persist not only between high and low-income regions of the world, but also within countries themselves. Against this background, the demand for PET diagnostics increases, which allows detecting cancer at the earliest stages.

The expansion of the industry is facilitated by the introduction of artificial intelligence. Neural networks help analyze medical images, minimizing human error. This improves diagnostic accuracy and streamlines the workflow, allowing radiologists and nuclear medicine professionals to make faster and more informed decisions. In addition, AI algorithms make it possible to form personalized treatment plans taking into account the physiological characteristics of a particular patient and his condition.

The authors of the study call the high cost of oncological positron emission tomographs and corresponding diagnostic procedures a deterrent. Problems in supply chains create additional obstacles to the development of the industry.

Geographically, North America was leading in 2024, accounting for 52.6% of spending, or $6.17 billion. The highest growth rates are recorded in the Asia-Pacific region, driven by increased demand for advanced imaging systems and significant investment in health care. Globally, significant players are named:

• GE Healthcare;
• Sonic Healthcare;
• Oncovision;
• Koninklijke Philips;
• Apex Radiology;
• Alliance Medical;
• Novant Health;
• Canon Medical Systems;
• Dignity Health;
• Concord Medical;
• Siemens Healthcare;
• Mediworks.

In 2025, the market size is expected to reach $12.31 billion. Fortune Business Insights analysts believe that in the future, the CAGR will be 5.6%. Thus, by 2032, costs may increase to $18.04 billion.^[2]

Global Heart PET Research Market Growth to $1.91 Billion

At the end of 2024, the costs on the global market for positron emission tomography (PET) of the heart amounted to $1.91 billion. More than half of global spending was provided by the North American region. Such data are provided in the Fortune Business Insights review published on July 2, 2025.

PET is a diagnostic technology involving the use of radiopharmaceuticals. The method is based on tracking the distribution in the body of biologically active compounds labeled with positron-emitting radioisotopes. With such a scan, pathological changes are recorded at the molecular level, due to which diseases can be detected at the initial stage. Isotopes enter the patient's body in minimal doses that do not harm health. Among the advantages of PET diagnostics are high reliability of results, lack of age restrictions, painlessness and safety.

𝓲

Фото: Freepik

When used in cardiology, PET diagnostics make it possible to assess the state of heart muscle tissues and, based on the obtained data, form a treatment plan or determine the need for surgery. In particular, the diagnosis of coronary heart disease is based on the identification of myocardial ischemia zones against the background of load.

One of the drivers of the analytics market is the increase in the prevalence of cardiovascular diseases (CVD), coupled with an increase in the number of elderly people. According to the World Organization, health care CVDs are the leading cause of death worldwide, killing 17.9 million people each year. More than four in five CVD deaths occur as a result heart attack of and, stroke with a third of these deaths being premature and occurring among people under the age of 70. In such a situation, the demand for diagnostic procedures, including PET, is growing.

Technological advances have a stimulating effect on the industry. Market leaders are investing heavily in the development of advanced visualization systems that provide high detail. Such equipment helps in the formation of personalized treatment strategies, which leads to an increase in the effectiveness of therapy. Combined PET/CT systems are gaining popularity, combining two imaging technologies - positron emission and computed tomography. In this case, PET allows obtaining data on the functional features of the body, and CT makes it possible to form a three-dimensional model of the examined organ.

Among the restraining factors, analysts call the high cost of PET scanners, as well as the lack of qualified specialists in the field of nuclear medicine. In addition, in some regions there may be problems with the availability of radiopharmaceuticals.

Geographically, North America leads the global PET heart research market with a 55.5% share, or $1.06 billion. The Asia-Pacific region shows the highest growth rate. Significant players on a global scale are:

• RadNet;
• Sonic Healthcare Limited;
• Akumin;
• Apex Radiology;
• Alliance Medical Limited;
• Novant Health;
• InHealth Group;
• Dignity Health;
• Concord Medical;
• Siemens Healthcare Limited;
• Mediworks.

In 2025, the costs in the market under consideration are expected to reach $1.97 billion. Fortune Business Insights analysts believe that in the future, the CAGR will be 3.8%. As a result, by 2032, spending could increase to about $2.56 billion.^[3]

Metropolitan scientists have created a calculator for calculating the effective dose of radiation load of a patient in radionuclide diagnostics

Specialists of the Moscow Center for Diagnostics and Telemedicine DZM have created calculators to calculate the effective dose of radiation load of patients during radionuclide diagnostics. According to the 3-DOZ Federal Reporting, such studies in Moscow occupy a leading position among high-dose procedures, so it is extremely important to correctly determine the effective dose and correctly register it in medical documents. These calculators greatly speed up these processes. Access to such tools was provided to all medical institutions in the country. This was announced on November 8, 2024 by Yuri Vasiliev, chief radiologist of Moscow, director of the Center for Diagnostics and Telemedicine of the Moscow Department of Health. Read more here.

2023

PET/full-body CT scanner presented, which is inexpensive and displays images without noise

On June 24, 2023, American researchers at Washington University in St. Louis (WUSTL) reported the development of a new system that combines positron emission (PET) and computer (CT) tomography capabilities. The solution is designed to scan the whole body to detect malignancies. Read more here.

A new word in treating depression and Alzheimer's. The resolution of PET scanners was first increased to a level that allows counting the nuclei of the brain stem

On June 24, 2023, Canadian researchers at the Sherbrooke Center for Molecular Imaging announced the development of an ultra-high resolution positron emission tomograph (PET). This scanner is expected to help treat all sorts of ailments, including Alzheimer's disease.

PET is an actively developing diagnostic and research method of nuclear medicine. It is based on the registration of a pair of gamma quanta arising from the annihilation of positrons with electrons. The method makes it possible to study various processes, such as metabolism, transport of substances, ligand-receptor interactions, gene expression, etc.

Canadian researchers at Sherbrooke Center for Molecular Imaging announce development of ultra-high resolution positron emission tomograph (PET)

The new PET scanner provides high spatial resolution - 1.25 mm, which is twice as much as a high-resolution research tomograph (HRRT). In this way, the nuclei of the brain stem can be visualized and quantified. This makes it possible to detect early changes associated with many diseases.

Positron emission tomography is useful in the study of neurological phenomena and for diagnostic purposes, but until now its potential has been somewhat limited by poor spatial resolution. The ultra-high resolution scanner is a qualitative leap in PET technology. It opens up new possibilities for early diagnosis of various conditions, "said Vincent Doyon, a master's student in radiation sciences and biomedical research.

The developed system allows characterizing previously indistinguishable areas of the brain that can be associated, in particular, with Alzheimer's disease, depressive disorders, visual perception disorders, tinnitus and other conditions. In addition, the new scanner can be used for research purposes.^[4]

New PET scan method developed to detect inflammation

At the end of January 2023, a tool called a LW223 for a positron emission tomograph for scanning to detect inflammation was presented. Researchers received just under $2.5 million to test it. Read more here.

2022

GE Healthcare has released its first all-digital PET/CT scanner

In mid-October 2022, GE Healthcare introduced the first fully digital PET/CT system in its range for the diagnosis of cancer. Positron emission tomography combined with X-ray computed tomography, which is a hybrid radionuclide diagnostic technique widely used in oncology worldwide. Read more here.

A portable PET device for scanning certain organs is presented

In early July 2022, Radialis Medical introduced the Radialis PET Imager portable positron emission tomography imaging machine. The system entered the market with the ability to adapt to the patient, and not vice versa, the manufacturer claims. Read more here.

2021

PET/full-body CT scanner announced for $8.9 million

At the end of July 2021, Quibim, which develops AI solutions for analyzing medical images, joined a Spanish project worth $8.9 million to create a PET/CT scanner for simultaneous imaging of the entire body. Read more here.

PET is the most effective tool for detecting recurrent brain metastases

In early May 2021, a study was published in The Journal of Nuclear Medicine, the results of which say that positron emission tomography (PET) is the most effective tool for detecting metastases brain and evaluating the effectiveness of modern treatments. When the results MRI of -monitoring are unclear, the addition of PET with 18F-FET helps physicians accurately diagnose recurrent brain metastases and reliably assess the patient's response to therapy.

New treatment options for patients with brain metastases, such as immune checkpoint inhibitors and targeted therapy, are quite effective but can cause many side effects. In this regard, the results of MRI imaging with contrast enhancement can vary greatly, and it becomes difficult to assess the response to treatment.

PET is the most effective tool for detecting brain metastases

In fact, these new treatments require brain imaging that cannot be performed with conventional MRI, "explained Norbert Galldiks, professor of neurology, neurologist and neuro-oncologist at the University Hospital of Cologne and Research Center in Jülich. - In our study, we tried to determine whether adding PET 18F-FET could help overcome some of these problems.

The retrospective study included patients with melanoma and lung cancer with brain metastases who received treatment with immune checkpoint inhibitors or targeted therapy alone or in combination with radiation therapy. Researchers have shown that PET results with 18F-FET can help doctors assess the response when routine MRI data is insufficient. Thanks to PET, doctors were able to correctly identify recurrence of brain metastases and identify patients who responded to treatment.^[5]

2020: New PET/CT method for prostate cancer diagnosis emerges

At the end of October 2020, the researchers presented evidence that the PET/CT technique with PSMA (prostate specific membrane antigen) allows us to effectively differentiate localized and metastatic cases of high-risk prostate cancer (PC).

The stage of PCa is usually determined by computed tomography, in particular the abdominal cavity and pelvis, as well as osteoscintigraphy. However, in such cases, the volume of disease often remains underestimated due to the low sensitivity of these methods. The researchers conducted a posterior analysis and believe that a higher sensitivity of PET/CT with PSMA allows us to detect PCa metastases in time, and conception can favorably affect the results of PCa treatment at high risk.

New PET/CT scan to diagnose prostate cancer comes

The study evaluated 249 high-risk/very high-risk PCa patients who underwent PET with PSMA between December 2016 and January 2020. The new technique made it possible to accurately assess the status of the disease, and also revealed the local spread of cancer beyond the prostate gland, invasion of the seminal vesicles or into the surrounding structures in 8.1% of patients assigned to stage T2 in previous MRI. Overall, PET with PSMA revealed 19.7% of patients with regional lymph node involvement and 9.4% of patients with metastatic involvement. Although these areas have not always been confirmed by biopsy, it can be argued from previous studies that 85-98% of the lesions detected are PC metastases.

The researchers believe that earlier detection of metastases will allow personalization of treatments and significantly improve the results of therapy in patients during the early stages of metastasis. Despite the high sensitivity of the method, the use of PET/CT with PSMA is still limited.^[6]

2017: Siemens Healthcare fixes vulnerabilities in PET scanners

On August 7, 2017, Siemens Healthineers announced a software update for positron emission tomography scanners. The company fixes vulnerabilities that hackers could theoretically exploit to break into this medical equipment. Read more here.

Notes