Nuclear Medicine / Molecular Imaging
Gamma Camera Acceptance Tests
Siemens / General Electric / Philips / Others
The purpose of acceptance testing is to verify a new or moved gamma camera meets NEMA, manufacturer and/or class specifications.
Acceptance tests are the most thorough and, therefore, the most costly tests necessary on gamma cameras.
Some of the images I acquire include intinsic flood field uniformity, intrinsic spatial resolution,
multiple window spatial registration and tomography.
The American College of Radiology (ACR) and some states require acceptance tests on all new gamma camera installations and
cameras that have been moved.
According to the ACR's Nuclear Medicine and PET Requirements
, "Acceptance tests must be performed on systems when they are installed."
Considering the cost of acceptance tests represents a very small percentage of the purchase price of the camera, acceptance
testing should always be performed even if your state or the ACR doesn't require it.
I have seen these tests pay for themselves on many occasions.
Dr. L. Stephen Graham reported to a AAPM group in 2000 that less than 25% of new gamma cameras installed met all specifications.
The two images above are from a 2009 acceptance test taken on the same day, one week after installation.
Both images are from the same gamma camera and detector manufacturerd in 2009 by one of the top three manufacturers.
This detector exceeded all factory test specifications and even the uncorrected image on the left shows nothing unusual.
I sent the image on the right to factory service engineers for evaluation after I noticed the artifacts and
it was later confirmed the detector has crystal hydration.
The manufacturer replaced the detector costing over $100,000 and paid for me to retest the camera.
Without acceptance tests by an experienced physicist, patients would have been imaged with the defective detector.
Furthermore, it is likely the crystal hydration would have gone unnoticed until after the warranty expired because artifacts can be masked by correction.
It is not part of any nuclear medicine technologist quality control protocol to perform the tests I did that revealed the crystal damage.
Photo shows NEMA hardware used for Acceptance Tests
on General Electric Infinia H3000WT dual-detector SPECT camera
Some manufacturers or installation engineers may perform a few NEMA tests after installation but I have never seen even half
of the tests performed that the majority of the American Association of Physicists in Medicine considered necessary in a 2009 survey.
Furthermore, the only factory NEMA tests I have seen were performed with Co-57 and not with any isotopes used on actual patients.
Only when an acceptable protocol of acceptance tests have been performed after installation can you be sure a camera is ready for patient use.
An unbiased third party can provide quantitative verification and a written report that your new system meets the standards and specifications you paid for.
Dates and times:
I require two days for acceptance tests.
I prefer to start no later than 3:00 PM. If the camera is operating
per factory specifications, I can complete acceptance
tests on a dual-detector camera in two days. There's no way to guarantee
a finish time and re-testing all or parts of the protocol are possible.
I've had mechanical problems that have delayed
finishing the tests on the first or
second day with or without warning.
Items that must be provided by your facility:
1. Hardware may be required for acceptance tests on your nuclear medicine cameras.
Please call me with the make and model of your system for testing requirements.
It may take some time to get required hardware shipped to your facility so please call me as soon as possible.
Any remaining hardware and phantoms will be provided by myself.
2. Isotope(s). I'll specify what's needed at your facility for each day.
3. Hot lab access with needles and syringes.
I'm licensed to handle isotopes.
I'm also a Radiation Safety Officer.
Please contact me for a proposal today.
Assurance tests are highly recommended and may be required at
your facility on a regular basis once the instrument has passed the
[ACR Nuclear Medicine Accreditation]
[Gamma Camera Performance Tests]
[Nuclear Medicine Scintillation Camera Acceptance Tests]
[Nuclear Medicine Resources]
© 2006 - 2011, Daryl Graham. All rights reserved.