Lunar DPX-IQ, Operator'S Manual, Page: 41 / 166

DPX-IQ Operator’s Manual Quality Assurance 3-3
Figure 3-2. Quality Assurance printout
3.1.2 Collimation Ratio Test
If the system fails the Collimation Ratio test, you cannot access the forearm and small
animal acquisition programs. A warning message shows when you try to enter either
program. Call the LUNAR Customer Support Department if your system fails the
collimation ratio test.
NOTE: Scan modes turned off by a Collimation Ratio failure are not shown
in the Mode window during scan acquisition.
3.1.3 Quality Assurance Warning Messages
If you do not complete daily QA tests, a warning message shows on the screen.
No Valid QA Results within the Past 48 Hours
If you start a scan, and did not complete a QA procedure in the last 48 hours, a
warning message is shown. Complete a QA test when this message is shown: 1) select
!
to access the Acquisition screen, or select
/
to go back to the Options screen;
and 2) select
%
to begin a QA procedure.
QUALITY ASSURANCE RESULTS
X-Ray Voltage (kVp) 76.0 Date 01/01/98
X-Ray Current (uA) 150.0 System 0000
AMPLIFIER COUNTS COUNTS
SETTING LOW keV HIGH keV
265 59862 1882
315 66818 1466
365 61837 5421
415 49942 22550
465 59495 58717
515 71869 66958
565 66845 59814
615 46454 49888
665 24989 57616
715 11056 78989
765 4861 68768
DETECTOR
AMPLIFIER SETTING
C
O
U
N
T
S
PROCEDURE VALUE EVALUATION
Lights - Pass
Peak Setting 520 units Pass
Background (Low keV) 2 cps
(High keV) 1 cps Pass
Beam Stop Action - Pass
Percent Spillover 8.33 % Pass-Good
Chi Square 2 Pass
Air Counts (Low keV) 748500 cps Pass
(High keV) 467236 cps Pass
Air Ratio 0.62 Pass
Transverse Mechanics 10948/10949 steps Pass
Longitudinal Mechanics 13378/13378 steps Pass
Tissue Value 1.313 Pass
Collimation Ratio 4.254 Pass
--------------------- ---------------- ------------
1 2 3 4 5 MEAN SD %CV
------ ------ ----- ------ ------ ----- ------ ------
LARGE BM 276.6 277.0 277.1 277.2 277.3 277.0 0.25 0.09
WIDTH 500 499 499 498 499 499 0.63 0.13
MEDIUM BM 203.3 206.8 206.4 205.2 205.5 206.0 0.58 0.28
WIDTH 434 434 429 429 432 432 2.24 0.52
SMALL BM 147.0 146.9 147.5 146.5 147.6 147.1 0.42 0.28
WIDTH 366 364 363 362 362 363 1.50 0.41