neoprobe
TM
GDS Operation Manual
AW-000639
Page
27 of 38
4.
Press Radionuclide Selection button on back of unit to select an open energy window (select
125
I Radionuclide
for units with v2.01 or earlier software or press
and hold Radionuclide button for an open energy window in
units with v2.02 or later software.)
5.
Press and hold Target Count Button to perform a 10 second count. Record this value. Divide
57
Co 10-second
count by open energy window 10-second count. Results should be greater than 50%.
6.
Count-rate ratio determined by this procedure should be stable and consistent over time within expected
+10% statistical variations of radioactive emissions during recommended counting intervals.
If result indicates variation from specified amount, and indicates performance has changed or is not stable, check for
proper setup with desired Radionuclide selected, and that all external factors (source, strength, source distance, stray
radiation, etc.) have been determined and controlled. Contact Devicor Medical Products, Inc. for technical assistance.
Performance Check
Perform periodic performance checks to assure proper performance of product. No calibration or adjustments are
needed. Regardless of probe type or radioisotope in use, this performance check is a simplified procedure that will
check proper performance of system with either probe type.
Performance check procedure
This performance check should be performed before each use.
1.
Place probe near source of radioactivity, i.e., injection site on patient. Verify that registered counts are greater
than zero.
2.
Position probe several feet away from source of radioactivity. Verify that registered count level decreases from
source count level.
If performance check does not meet conditions of Steps #1 and #2 above, consider following:
If probe fails to detect measureable levels of gamma emissions when positioned over source of radioactivity,
check that power is on and that correct radionuclide is selected. For low counts, run system diagnostic checks to
test all visual indicators are functioning properly. Contact Devicor Medical Products, Inc. for technical assistance
if problem continues.
If console displays error codes “
error 2
” through “
error 6
” when powered on, or anytime during operation,
cycle power to console. Contact Devicor Medical Products, Inc. if error codes continue.
If console indicates high level of gamma emissions when probe is pointed away from radioactive source, and no
other source of radiation is known, move to another room and repeat low count performance check.
o
If counts go down, there must be another source of radioactivity in room or patient source is too high.
o
If counts do not go down, probe may be contaminated and should be cleaned with a radioactive
decontaminant solution (e.g., Radiacwash®), or probe has internal mechanical damage.
Troubleshooting
Use this table to identify and correct problems. Additional information is provided in service manual.
Artwork No: AW-000639 Revision: A Artwork Status: Released Lifecycle Name: Artwork
PCO No: N/A ECN No: ECN-000214 Release Date: 10/09/2012 Effective Date: 10/09/2012
