Jaszczak phantom

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A Jaszczak phantom (pronounced "JAY-zak") aka Data Spectrum ECT phantom [1] is an imaging phantom used for validating scanner geometry, 3D contrast, uniformity, resolution, attenuation and scatter correction or alignment tasks in nuclear medicine. It is commonly used in academic centers and hospitals to characterize a SPECT or some gamma camera systems for quality control purposes. It is used for accreditation by clinical and academic facilities for the American College of Radiology. [2] [3]

Contents

The phantom was developed by Ronald J. Jaszczak [4] of Duke University, [5] and was filed for a patent in 1982. [6] It is a cylinder containing fillable inserts that is often used with a radionuclide such as Technetium-99m [7] or Fluorine-18. [8]

Although the phantom can be used for acceptance testing, the National Electrical Manufacturers Association recommends a 30 million count acquisition and section reconstruction of the phantom be performed quarterly. [9]

In 1981 Ronald J. Jaszczak founded Data Spectrum Corporation which manufactures the Jaszczak phantom and several other nuclear imaging tools, [10] such as the Hoffman Brain phantom.

Structure and composition

Jaszczak phantoms consist of a main cylinder or tank made of acrylic plastic with several inserts. The circular phantom comes in two varieties: flanged and flangeless. The latter is recommended by the American College of Radiology for accreditation of nuclear medicine departments. [11] All Jaszczak phantoms have six solid spheres and six sets of 'cold' rods. In flanged models, the sizes of the spheres vary. The number of rods in each set depends on the size of the rod in that set as different models of the phantom have rods of different sizes. In flangeless models, the diameters of the spheres are 9.5, 12.7, 15.9, 19.1, 25.4 and 31.8 mm, while the rod diameters are 4.8, 6.4, 7.9, 9.5, 11.1 and 12.7 mm. Both solid spheres and rod inserts mimic cold lesions in a hot background. Spheres are used to measure the image contrast while the rods are used to investigate the image resolution in SPECT systems. [12]

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Molecular imaging

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PET-MRI

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Cardiac imaging

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References

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  3. "ACR Nuclear Medicine & PET Accreditation".
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  5. "Ronald Jaszczak, PhD". SNMMI Annual Meeting. Archived from the original on 2016-10-11. Retrieved 2016-07-02.
  6. USPATENT 4499375,Ronald J Jaszczak,"Nuclear imaging phantom",issued 1985-02-12
  7. Mattsson S, Hoeschen C. Radiation Protection in Nuclear Medicine. Springer. 2003. ISBN   978-3-642-31166-6. p.82
  8. Waterstram-Rich KM, Christian PE. Nuclear Medicine and PET/CT. 7th Ed. Elsevier Health Sciences, 2013. ISBN   0323277047 p.345
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  10. Jaszczak, Ronald Jack (7 July 2006). "The early years of single photon emission computed tomography (SPECT): an anthology of selected reminiscences" (PDF). Physics in Medicine and Biology. 51 (13): R99–R115. CiteSeerX   10.1.1.456.9131 . doi:10.1088/0031-9155/51/13/R07. PMID   16790923.
  11. "Phantom Testing: Nuclear Medicine". Accreditation Support. American College of Radiology. 4 February 2021. Retrieved 8 March 2022.
  12. Bailey DL, Humm JL, et al. Nuclear Medicine Physics: A Handbook for Teachers and Students. 2014. International Atomic Energy Agency publications. ISBN   978-92-0-143810-2. p.563