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1 http://www.meshalkinclinic.ru/departments/images/isotop/gamma5.jpghttp://www.stresslabs.com/first_pass_gam.html

2 Multicrystal Gamma Camera Higher detection efficiency than Anger Cameras Uses a physical matrix of scintillation crystals separated by lead strips Collimator with holes corresponding to each crystal X/Y “lightpipe/PMT assembly replaces Anger positioning logic http://www.stresslabs.com/first_pass_gam.html

3 Old Style (True) Multicrystal Gamma Camera 294 Crystals 294 Collimator Holes Each Crystal : Two Lucite Lightpipes One Lightpipe : X Axis One Lightpipe : Y Axis Bank of 35 PMTs Minimizes “Crosstalk” Pulses from more than one crystal Improves Efficiency Paul Early, D. Bruce Sodee, Principles and Practice of Nuclear Medicine, 2nd Ed., (St. Louis: Mosby 1995), pg. 254.

4 Scinticor-Type “Multicrystal” Camera Not really a multicrystal Camera Uses crystal kind of like “Starbright” – slotted http://www.stresslabs.com/first_pass_gam.html Paul Christian, Donald Bernier, James Langan, Nuclear Medicine and Pet: Technology and Techniques, 5th Ed. (St. Louis: Mosby 2004) pg 69.

5 Multicrystal Gamma Camera Paul Early, D. Bruce Sodee, Principles and Practice of Nuclear Medicine, 2nd Ed., (St. Louis: Mosby 1995), pg. 254. 20 X 20 Crystal Elements 115 PMTs Anger-like Positioning Logic

6 Multicrystal Primary Use: First Pass http://www.bcit.ca/health/nuclearmed/gatedventricul.shtml http://www.stresslabs.com/first_pass_gam.html Bolus dose : Hi Concentration of Activity Quantifying Information Need Accurate Reading of Counts “Saturates” Anger Camera (Inaccurate Counts)

7 Solid State Gamma Camera http://www.asnc.org/section_96.cfm Uses an array of many scintillation crystals (either Cadmium Zinc Telluride or Thallium Activated Cesium Iodide) Based on the formation of “electron- hole pairs” (has to do with an electron moving between valence band and conduction band) Each crystal has its own photodiode (instead of PMT) Creates a positioning matrix rather than the positioning logic of the Anger system.

8 Solid State Gamma Camera—Digirad System http://www.digirad.com/tech_detector.shtm# 4,096 CsI(Tl) Crystals and Photodiodes Good Efficiency Hi Noise Potential Very Good Resolution (2mm Intrinsic) “Pixelated” FOV property lends itself to digitization Consistent performance across entire FOV

9 Cadmium Zinc Telluride Crystals http://www.answers.com/topic/bonded-assembly-jpghttp://www.answers.com/topic/cadmium-zinc-telluride?cat=technology

10 Solid State Gamma Cameras Have a small FOV Useful for dedicated purposes such as heart, breast, and brain imaging Are portable—useful in ICU situations Watch these---may eventually become the basis for all gamma cameras http://medgadget.com/archives/2006/12/scintimammograp.html

11 Images from Solid State System http://www.digirad.com/tech_results.shtm

12 Nuclear medicine techs and physician view cowardly lion scan http://www.homevideos.com/revmusic/10b.htm


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