Across
- 1. method used by the computer to filter out bad beats
- 4. allows for only the PMTs in the immediate vicinity of the event to contribute to the position location
- 5. mode that caps out the potential counts at 255 in a pixel
- 10. is a correction that is done by creating a linearity correction map by imaging precise linear phantoms & measuring the amount of displacement to produce straight lines in the image
- 12. creates a time activity curve
- 17. _____ smoothing used with dynamic(perfusion) image sets; weighted averaging occurs by looking at the frame before and after the frame to be altered and the frame being smoothed is given twice the weight
- 18. occurs when imaging too high an activity such that the pulses leaving the amplifier occur so rapidly that multiple pulses are handled as a single event and are rejected by the PHA
- 19. camera's ability to stop gamma rays and collect counts
- 20. _____ activity is the main loss of contrast in planar nuclear medicine
- 21. used to improve the spatial resolution of small organs, such as the heart or thyroid
- 22. a dynamic sequence of images viewed in a continuous loop
- 23. mode that equals 16 bits of information (2 bytes); takes up 2X the memory requirements
- 26. occurs when counts in each pixel in the image matrix are compared and lowest count pixel is used as a reference and the counts in the higher counting pixels are lowered
- 27. of the camera is placed inside the matrix
- 28. uniform shading between all count levels
Down
- 2. mode where a digital image is built in the computer's memory as the signals are received
- 3. method that assigns gray scale to pixel display suppressing high count pixels while increasing number of shades of gray to the lower count pixels
- 6. is done by collecting a high number of counts and setting up slightly different energy windows for each pixel in the matrix
- 7. a shading that enhances differences in the high count pixels
- 8. _____ smoothing is readjusting pixel count by looking at its 8 nearest neighbors; reduces image noise from low count values in individual pixels
- 9. statistical variations in the number of counts in the pixels that create the image
- 11. can occur in the camera display from spatial distortion and energy variation
- 13. method of increasing the camera's sensitivity by stopping the signal collection at the PMT anode after most of the scintillation photons have been registered
- 14. analyzed by PHA; determines if energy is counted or not (fit in the window)
- 15. occurs when a high count pixel is selected and the counts in the other pixels are increased
- 16. the camera's ability to clearly see detail; seeing objects as two separate objects
- 24. used in bkg subtraction when the ROI drawn is smaller than the ROI drawn around the organ of interest
- 25. mode that allows you to reformat a flow study by shortening the acquisition times of the individual frames that might have been collected over too long of a time interval