|NEMA® SCA&I Cardiovascular/Fluoroscopic Benchmark Phantom.|
For voluntary compliance with NEMA XR 21|
The CIRS Model 901 NEMA SCA&I phantom was designed to evaluate and standardize catheterization image quality. It is
|the result of collaborative efforts between the Society for Cardiac Angiography and Interventions and the National
Electric Manufacturers Association. The phantom specifically enables voluntary compliance with the recently published
performance standard NEMA XR 21.|
The Model 901 is manufactured from PMMA with x-ray absorption properties similar to soft tissue at diagnostic energies. It contains a variety of static and dynamic test targets for objective assessment of resolution, motion unsharpness and radiation exposure. The sectional design allows for configuration in a wide range of thicknesses from 5 cm to 30 cm simulating PA thicknesses from infants to large adult patients.
The phantom is ideal for routine assessment of the entire imaging system.
|NEMA® Cardiology Phantom.|
The NEMA Cardiology Phantom was designed by collaboration with SCA&I to provide a cardiovascular fluoroscopy benchmark phantom. It is used to test systems under conditions simulating normal clinical use for fluoroscopically guided invasive and interventional procedures.
The phantom test ensemble includes tests for imaging-field geometry, spatial resolution, and low-contrast iodine detectability, working thickness range, motion unsharpness and phantom entrance dose.
Test objects are positioned at the center of the NEMA Cardiology Phantom. This simulates the location of clinically important organs. The NEMA Cardiology Phantom, positioned with its center at the x-ray system's isocenter, simulates clinical imaging geometry. Therefore, the geometric magnification of the test objects is similar to that of the clinical target. The receptor blur, focal spot penumbra blur and x-ray scatter are also similar in test and clinical conditions. The entrance surface of a thick phantom is closer to the x-ray tube than the entrance surface of a thin phantom. This is an additional reason why patient (phantom) dose increases with phantom thickness.
|iodine dispersed in epoxy. The relative areal concentration of iodine in the four patterns is 20, 10, 5, 2.5 mg/cm2. The
test operator is required to identify the smallest visible pair of targets in each pattern. See Figure 4
How does the NEMA Cardiology Phantom actually work?
The field size plate is placed on top of the phantom. A second plate with a centered radiopaque dot is placed in the base. The imaging gantry is adjusted until the cross wires intersect the approximate center of the disk. See Figure 7
- Photographs A and B demonstrate acceptable alignment of the NEMA phantom.
- In fluorograph A, the spatial resolution test plate and several of the low contrast detectability targets are shown. Both lines cross at the dot.
- Fluorograph B shows both lines crossing at the dot. (The test plates have been removed.)
- Fluorographs C and D demonstrate poor alignment of the NEMA phantom.
- In fluorograph C, the spatial resolution test plate and several of the low contrast detectability targets are also seen in this image. The instersection of the two lines is outside the dot.
- Fluorograph D shows the instersection of the two lines outside the dot. (The test plates have been removed.)
Included accessories: Phantom, rotation target (110 V or 22 V), test stand, alignment pins, x-ray test pattern, and carrying case.