Compact PET or CT
Sedecal offers their Compact PET or Compact CT systems as an alternative to the SuperArgus PET/CT. The Compact PET system incorporates the same state-of-the-art detectors and electronics as the SuperArgus systems. The compact systems have a bore size of 55mm making it ideal for mouse imaging. There is a common bed to transport the animal between imaging systems if the researcher is looking to coregister the images.
The core of the compact scanner is the unique phoswich PET detector technology, which provides true depth-of-interaction (tDOI), providing resolution (≤1.0mm) uniformity across the entire field of view. These detectors are also some of the most sensitive (11% at 100-700keV), allowing for real-time imaging (up to 2.5msec frame rate if desired).
The Compact PET system includes 32 tDOI phoswich detectors, configured in 4 rings, with an axial field of view of 45mm, and a trans-axial field of view of 100mm. The Compact CT system has the same axial and trans-axial fields of view, with a maximum resolution of 65µm. Both systems have the same overall dimensions of 60 x 60 x 40cm; with the Compact CT system being self-shielded to meet FDA standards. The animal handling system from each system is interchangeable with the other, allowing the mouse to remain in position while moved from one system to the other for multi-modal image acquisitions.
The Compact PET system includes Sedecal’s state-of-the-art detectors resulting in one of the most sensitive systems on the market today, this and the Compact CT system have been designed as mouse only systems for those who do not require the axial field of view provided by the larger SuperArgus systems.
The phoswich detectors are key to the unique features of the system:
- Provide true depth of interaction (tDOI) information resulting in
- Highest resolution on the market; ≤1.0mm
- Uniform resolution across the entire field of view (45mm axial FOV), with the field of view filling the majority of the bore of the system due to the parallax error correction
- Highest sensitivity on the market; 14% at 100-700keV
Sedecal has optimized the electronics and algorithms to perform precise image reconstruction very quickly. These are some of the more common reconstructions available on the system:
- FBP (Filtered Back Projection) completed in less than 5 seconds
- 2D OSEM (Ordered Subset Expectation Maximization) completed in less than 1 minutes
- 3D OSEM completed in less than 2 minutes
Taken as a whole, the Compact PET or CT systems provide best-in-class image quality, as seen here on an 18F PET bone scan image:
The Compact PET system is a 4 ring system, including 32 tDOI phoswich detectors, with an axial field of view of 45mm, and a trans-axial field of view of 100mm. The Compact CT system has been designed to minimize the radiation exposure, making it ideally suited for longitudinal imaging studies. This system as the same axial and trans-axial fields of view as the Compact PET system, with a maximum resolution of 65µm. Both systems have the same overall dimensions of 60 x 60 x 40cm; with the Compact CT system being self-shielded to meet FDA standards. The animal handling system from each system is interchangeable with the other, allowing the mouse to remain in position while moved from one system to the other for multi-modal image acquisitions. The systems provide integrated inhaled anesthesia connections along with heating options to help maintain the temperature of the mouse throughout the imaging session.
The key benefits of the Compact systems include:
- State-of-the-art phoswich detectors in the Compact PET system, providing
- Provide true depth of interaction (tDOI) information resulting in
- Highest resolution on the market; ≤1.0mm
- Uniform resolution across the entire field of view (45mm), with the field of view filling the majority of the bore of the system due to the parallax error correction
- Highest sensitivity on the market; 14% at 100-700keV
- Provide true depth of interaction (tDOI) information resulting in
Optimized reconstruction algorithms on the Compact PET system- FBP (Filtered Back Projection) completed in less than 5 seconds
- 2D OSEM (Ordered Subset Expectation Maximization) completed in less than 1 minutes
- 3D OSEM completed in less than 2 minutes
- Interchangeable animal handling systems to allow multi-modal imaging, as the system moves from the Compact PET to Compact CT system seamlessly
- Self-shielded design of the Compact CT system, meeting FDA guidelines, reducing infrastructure requirements for installation
Oncology is one of the most common applications of PET in preclinical imaging. Used clinically to detect small metastatic lesions throughout the body, preclinical applications of PET imaging are diverse. PET tracers have been developed to study:
PET imaging may be used on any type of tumor model, as the radiotracers are typically injected intravenously for distribution to all areas of the body. Specifically, PET imaging may be used on orthotopic and transgenic/spontaneous tumors, as well as xenografts or metastatic lesions. |   The above images and data come from a paper published by R.C. Mease et al. in Clinical Cancer Research [2008; 14(10)]. In this study they investigated the time vs. intensity curve of 18F-DCFBC, a radiotracer specifically designed to target prostate-specific membrane antigen. In this study the tumor on the left shoulder of the mouse was PSMA+ while the tumor on the right was PSMA-. This group also studied the activity in other organs such as the blood, kidneys, and liver. The above images were acquired using the SuperArgus PET/CT system; however, the same performance can be expected from the Compact PET systems for mouse only imaging. |
Neurological applications of PET are commonplace both clinically and preclinically. Preclinical PET tracers have been developed to study:
PET imaging has been used to study the pathological processes, response to therapeutics, and resolution of many disease models, including Parkinson’s Disease, Alzheimer’s Disease, Huntington’s Disease, Stroke, Epilepsy, Traumatic Brain Injury, and Neuropsychiatric disorders. |  In the study above, which was featured on the cover of Journal of Neurochemistry [2015. Vol. 133(3)], Dr. Stephanie Kramer’s group studied the biodistribution of a novel metabotropic glutamate receptor 5 (m-Glu-R5) which utilized F-18 rather than C-11. This tracer is important in studying the synaptic plasticity and modulation of neural network activity, which is relevant in a number of psychiatric and neurological disorders. Previously, this work typically used a C-11 tracer; with the development of an F-18 tracer to do similar work the logistics of carrying out such studies becomes increasingly easier due to the longer half-life of F-18 compared to C-11. The above images were acquired using the SuperArgus PET/CT system; however, the same performance can be expected from the Compact PET systems for mouse only imaging. |
Cardiology applications of PET are commonplace both clinically and preclinically. Preclinical PET tracers have been developed to study:
Many different cardiovascular diseases may be investigated using PET imaging, including coronary artery disease, myocardial infarction, or heart failure. | |
The recent COVID-19 pandemic has brought to the forefront the importance of PET imaging in immunological and infectious disease research. A survey of the literature shows that preclinical PET imaging has been shown to be invaluable in studying the following:
- Understanding disease progression and pathogenesis
- Diagnosis of disease, by targeting the specific pathogenic agent
- Studying therapeutic efficacy of target compounds
- Optimizing treatment regimens and studying the resolution of infections
- Understanding the host’s immune response to infection
- Studying the efficacy of vaccines
Infectious diseases and immunology are not limited to the study of viruses, but rather go well beyond these specific agents to look at models of bacterial, viral, parasite, and prion infections. The only limitation to this type of work is in the PET tracers available to investigate both the infectious agent as well as the host’s response.
| Dynamic PET imaging is often used to study the kinetics of a newly developed PET tracer, or to investigate target concentrations, or biodistribution. Time-activity curves are often prepared along with assessments of radiotracer accumulation and biodistribution kinetic modeling.
In the images and data shown above, the first pass of FDG (flurodeoxy glucose) can be quantified in the tail vein, as well as the subsequent saline flush at approximately 14 seconds. The above images were acquired using the SuperArgus PET/CT system; however, the same performance can be expected from the Compact PET systems for mouse only imaging. |
| A variety of bone diseases may be studied using PET imaging, these include but are not limited to osteoporosis, osteomalacia, rickets, or rheumatoid arthritis. A wide variety of other diseases, including metabolic disorders, can also be studied using PET imaging. There is truly no limit on the application of PET in preclinical imaging, it is merely dependent on the development of specific and relevant PET tracers. |  The above image shows increased metabolic activity in the paws of this arthritic rat model. |
| Model | Argus Compact | SuperArgus PET/CT 2r | SuperArgus PET/CT 4r | SuperArgus PET/CT 6r | SuperArgus PET/CT 2R | SuperArgus PET/CT 4R | SuperArgus PET/CT 6R | SuperArgus PET/CT 4P | SuperArgus PET/CT 6P |
| Animals | Mice only | Mice, rats and marmosets | Mice, rats and marmosets | Mice, rats and marmosets | Mice, rats, marmosets, rabbits (3 kg) | Mice, rats, marmosets, rabbits (3 kg) | Mice, rats, marmosets, rabbits (3 kg) | Non-human primates; canine; porcine, murine (10 kg) | Non-human primates; canine; porcine, murine (10kg) |
| Dynamic AFOV | 100 mm | 220 mm | 220 mm | 220 mm | 350 mm | 350 mm | 350 mm | 650 mm | 650 mm |
| Static AFOV | 100 mm | 50 mm | 100 mm | 150 mm | 50 mm | 100 mm | 151 mm | 100 mm | 150 mm |
| TFOV | 50 mm | 80 mm | 80 mm | 80 mm | 120 mm | 120 mm | 120 mm | 210 mm | 210 mm |
| Bore size | 55 mm | 90 mm | 90 mm | 90 mm | 160 mm | 160 mm | 160 mm | 260 mm | 260 mm |
| Detectors | 32 | 28 | 56 | 84 | 48 | 96 | 144 | 128 | 192 |
| DOI crystals | 10816 | 9464 | 18928 | 28392 | 16224 | 32448 | 48672 | 43264 | 64896 |
| Model | Basic | Advanced | Extended |
| Rotation | Continuos | Continuous | Continuous |
| FOV | 70 x 180 mm | 120 x 350 mm | 210 x 650 mm |
| Zoom | No | Yes | Yes |
| Acquisition time | 15 s | 15 s | 15 s |
| Spatial resolution | 50 µm | 15 µm | 20 µm |
| Flat panel | CMOS and Cs plate | CMOS and Cs plate | CMOS and Cs plate |
| FPS | 86 | 86 | 86 |
| Detector Active Area | 12 x 15 cm | 23 x 15 cm | 29 x 23 cm |
| Number of pixels | 1944 x 1536 | 3072 x 1944 | 3888 x 3072 |
| X Ray Energy peak | 50 kV | 130 kV | 130 kV |
| Source spot | 35 µm | 7 to 100 µm | 7 to 100 µm |
| Max Power | 50 W | 65 W | 65 W |
| X Ray Protection | Auto shielded according FDA | ||
