NEMA Standard Phantoms
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NEMA NU 4-2008
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SPECT-IQ
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Key features
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• Bubble trap to keep air out of the active volume
• Chamfers added in corners to remove undesired air bubbles • Countersunk screws allowing easy of filling on flat surface • Automatic segmentation and analysis with Imalytics (Gremse-IT) Preclinical Software -Quantification generated with the click of a button -Resolution -Scatter -Recovery coefficients -Uniformity • Customization available • Compatible with most imaging systems and modalities, including MRI |
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Description & Applications
Phantech manufactures economical phantoms that adhere to the National Electrical Manufacturers Association (NEMA) standards. Assembled with three main pieces and associated hardware, these standard NEMA phantoms are available in two configurations: NEMA NU4-2008 (NU4IQ) and SPECT-IQ (as detailed in E.P. Visser et al. 2011, Nuclear Instruments and Methods in Physics Research A). These standard phantoms feature three fillable regions that allow the assessment of PET or SPECT scanner image quality (IQ) by representing typical hot, cold and uniform radioactivity in an animal.
Common applications:
Common applications:
- Image quality & performance assessment
- spatial resolution
- uniformity
- signal-to-noise
- attenuation correction
- scatter correction
- spill-over
- scatter fraction/correction
- count losses
- random coincidences
- recovery coefficient
- Partial volume correction for dosimetry
- Co-registration (PET, SPECT, CT, optical, MRI, MPI)
- Reconstruction optimization
- Multi-modality applications
- Standardization
- Training
- Marketing
NEMA NU 4-2008 Additional Info
The National Electrical Manufacturers Association (NEMA)) developed the NEMA NU-4 2008 standard in order to assess the performance of small animal Positron Emission Tomographs (PET) systems regardless of their camera setup. Per the scope of this NEMA standard, “[c]amera designs such as circular ring geometry of discrete crystal or continuous block detectors, planar detector (rotating or stationary), continuous crystals, gas avalanche detectors, time-of-flight or no time-of-flight, single slice or multi-slice dedicated PET tomographs and other coincidence capable imaging systems are covered by this procedure.”
The NU4IQ phantom has a main body that is fillable with ~20.5mLs of a homogenous concentration of radioactivity. Adjacent to it is solid non-radioactive material with five radioactive fillable rods varying in diameter from 1-5mm. The lid to the large homogenous volume contains two chambers of ~0.75mLs that are filled with either non-radioactive water or air. With these compartments, one can assess the spatial resolution, recovery coefficient, uniformity, signal-to-noise, attenuation, scatter correction, spill-over, and scatter correction performance of a preclinical PET scanner.
Reference: NEMA, National Electrical Manufacturers Association, NEMA Standards Publication NU 4-2008. Rosslyn, VA, National Electrical Manufacturers Association, 2008
The NU4IQ phantom has a main body that is fillable with ~20.5mLs of a homogenous concentration of radioactivity. Adjacent to it is solid non-radioactive material with five radioactive fillable rods varying in diameter from 1-5mm. The lid to the large homogenous volume contains two chambers of ~0.75mLs that are filled with either non-radioactive water or air. With these compartments, one can assess the spatial resolution, recovery coefficient, uniformity, signal-to-noise, attenuation, scatter correction, spill-over, and scatter correction performance of a preclinical PET scanner.
Reference: NEMA, National Electrical Manufacturers Association, NEMA Standards Publication NU 4-2008. Rosslyn, VA, National Electrical Manufacturers Association, 2008
SPECT-IQ Additional Info
The SPECT-IQ phantom is essentially the NEMA NU-4 2008 phantom scaled down by 70 percent. However, the rod diameters are specifically chosen to be 0.35, 0.5, 0.75, 1.0 and 1.5 mm to accommodate the higher resolution capabilities of small animal SPECT scanners.
With these compartments, one can assess the spatial resolution, recovery coefficient, effective whole-body sensitivity, uniformity, signal-to-noise, attenuation, scatter correction, spill-over, and scatter correction performance of a preclinical SPECT scanner. Additionally, since there is a tradeoff between resolution and sensitivity with different collimators, one can use this phantom to characterize collimators in order to choose the most appropriate collimator for a specific application. Lastly, this phantom can be used to assist in making decisions for acquisition and image reconstruction parameters. For example, one can scan this phantom to determine the ideal number of iterations to use in a reconstruction that would recover enough signal to resolve small structures but would not introduce too much noise.
Reference: E.P. Visser, et al., Nucl. Instr. and Meth. A (2011), doi:10.1016/j.nima.2011.06.036
With these compartments, one can assess the spatial resolution, recovery coefficient, effective whole-body sensitivity, uniformity, signal-to-noise, attenuation, scatter correction, spill-over, and scatter correction performance of a preclinical SPECT scanner. Additionally, since there is a tradeoff between resolution and sensitivity with different collimators, one can use this phantom to characterize collimators in order to choose the most appropriate collimator for a specific application. Lastly, this phantom can be used to assist in making decisions for acquisition and image reconstruction parameters. For example, one can scan this phantom to determine the ideal number of iterations to use in a reconstruction that would recover enough signal to resolve small structures but would not introduce too much noise.
Reference: E.P. Visser, et al., Nucl. Instr. and Meth. A (2011), doi:10.1016/j.nima.2011.06.036
Available sizes
NEMA NU 4-2008 Phantom |
SPECT-IQ Phantom |
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Drawings and dimensions (units in mm)
Customization
Yes, we can customize our NEMA phantoms. Customization options include rod diameter, length and configuration, and overall outside diameter and length.
Contact us at [email protected] for custom requests!
Contact us at [email protected] for custom requests!
image and video gallery
PET Images (F-18)
Axial CT slice of the NEMA phantom showing the filled resolution rods, and the fiducial identification markers (cone shape) for the Imalytics automated analysis.
Imalytics Preclinical sofware volume rendering of SPECT-IQ scan with 99mTc
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Axial CT slice of the NEMA phantom showing the air and water chamber to assess scatter.
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SPecificiation sheet
| Phantech_NEMANU4-2008-GrIT&SPECT-IQ-GrIT_SpecSheet.pdf |
INNOVATIVE DESIGN
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This assembly consists of three manufactured components (two of which are sealed permanently together) and four separate pieces of commercial hardware for assembly.
The NEMA and SPECT-IQ phantoms have five hot rods with varying diameters and a large uniform region with two separately fillable chambers within it. |
AUTOMATED ANALYSIS WITH IMALYTICS PRECLINICAL (GREMSE-IT)
Automated Analysis Workflow
1. Fill NEMA/SPECT-IQ phantom
2. Perform imaging scan
3. Load image file into Imalytics
4. Select the phantom from the dropdown menu
5. Generate and save report
1. Fill NEMA/SPECT-IQ phantom
2. Perform imaging scan
3. Load image file into Imalytics
4. Select the phantom from the dropdown menu
5. Generate and save report
ORDER!