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DOC. ID: DXSE0012 MANUFACTURING PROCEDURES GE Medical Systems LUNAR

REVISION: G DATE: 2/28/02 WRITTEN BY: Jeff Franz APPROVED ON CO: L10173

TITLE: DEXA PM Work Instructions

PURPOSE This procedure describes the steps necessary to do a Planned Maintenance Check on a DEXA scanning system at a customer's site, and to assure that the system is operating within GE-LUNAR's specifications and in compliance with applicable Federal and State regulations.

APPLICATION This procedure applies to all employees performing Planned Maintenance or Site Certification of DPX Series or PRODIGY, and DPX-NT scanning systems.

SAFETY PRECAUTIONS When power is applied this equipment generates ionizing radiation. Take precautions that no part of your body passes through the x-ray beam when the equipment is energized.

ASSOCIATED MATERIALS DXAP0008 DXAP2007 DXAP3002 DXQC0022 DXQC2022 DXSE0036 DXSE0038

DPX-Series Installation Test Procedures Prodigy Hacksaw Test DPX-NT Installation Test Procedures Aluminum Spine Phantom Scan Procedure enCORE software Aluminum Spine Phantom Scan Procedure OINK Daughter board and Limit Switch Field Replacement Instructions DEXA PM Quality record

DEFINITIONS DPX Series scanners are all non- Prodigy, non- DPX-NT/MD+ scanners. enCORE based systems are all PRODIGY and DPX-NT/MD+ scanners. PRODIGY I systems are defined as PRODIGY systems with system numbers 11999 and lower. DPX-NT (A) systems are defined as DPX NT systems with system numbers 71999 and lower. QUALITY SYSTEM DOCUMENT

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It is the responsibility of the user to verify this document originated from the controlled master and is the active revision prior to use. This document contains confidential or proprietary information of GE Lunar. Neither the document nor the information therein is to be reproduced, distributed, used or disclosed, either in whole or in part, except as specifically authorized by GE Lunar.

GE Medical Systems LUNAR

DOC ID: DXSE0012

REV: G

DATE: 2/28/02

CO: L10173

PROCEDURE A. QA HISTORY AND ERRORLOG. 1. Perform a Quality Assurance test to insure the system is operating. a. Verify that all tests on the QA are passing. 2. DPX Series scanners: The QA values needed may be found by viewing the QA database (F4 Database options – F2 QA History) and / or in the Daily QA printouts in the Customer’s QA binder. a. Verify that the Detector has not lost significant resolution by checking that the high and low energy air counts have not decreased by more than 10% from the date of installation or the date of the last tube head or detector change). b. Verify that the air ratio has not changed by more than .02. from the date of installation or last tube head or detector change (calculate from earliest QA or lookup on QA printouts). 3. Systems with enCORE software a. Copy the QA.mdb file to a diskette (Tools / Send Configuration / Select Error Log and QA Database, make sure compress Files is selected and select Span Multiple Disks if necessary). b. Select the appropriate drive (3 ½ floppy A: ) insert disk into drive and click OK. c. Label with system number and PM, the file may be mailed to Service Engineering or email file to [email protected] NOTE: This is only to gather statistical information on enCORE based systems performance, there will be no follow up regarding these QA histories. 4. Analysis of the QA History file a. DPX Series i. Verify % Spillover is between 6.3 and 9.5 ii. Check the Air Ratio – it cannot deviate more than .02 since the last detector / tube change iii. Check the low air counts – a change greater than 10% since the date of last detector change indicates a failing detector iv. Check the Large standard Mass – should not deviate more than 2%

QUALITY SYSTEM DOCUMENT

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It is the responsibility of the user to verify this document originated from the controlled master and is the active revision prior to use. This document contains confidential or proprietary information of GE Lunar. Neither the document nor the information therein is to be reproduced, distributed, used or disclosed, either in whole or in part, except as specifically authorized by GE Lunar.

GE Medical Systems LUNAR

DOC ID: DXSE0012

REV: G

DATE: 2/28/02

CO: L10173

v. If any of the above parameters are failing, call GE-Lunar Customer Support for help diagnosing the system. 1. To aid in diagnosis, email the QA.MDB file to [email protected] 5. Review the error log(s). b. DPX Series systems print from DOS prompt i. C:\> ERRDUMP –L –N >PRN

c. d. e.

f. g.

1. See DPX Series CSB Vol 9 for DPX Series Error Log Interpretation enCORE based systems Tools\ Error Log – add to instructions Verify that there are no hardware subsystem failures (X-ray, Detector, Mechanical) Contact Lunar Service Department if any unexplained or unusual errors are discovered in the error log. i. Error Log may be faxed to 608-826-7107 to aid in interpretation. Delete error log for DPX Series (C:\LUNAR> del err_320.bin or C:\LUNAR del errlog.bin). Start a new error log for enCORE-based systems by clicking on Initialize Log.

B. HOST PC MAINTENANCE 1. Clean the Printer according to the manufacturer’s instructions a. For Hewlett Packard Printers go to www.hp.com and search the support pages for the customer’s printer model. 2. DPX series systems: a. From a DOS prompt i. Delete contents of C:\SCRATCH and C:\PRNTMNGR directories. ii. Delete all *.CHK files in C:\ directory. 3. Software updates a. DPX Series systems: all DPX-IQ densitometers may be updated to version 4.7e software free of charge. b. All other (non-IQ) DPX Series Densitometers should be running version 3.65 or 4.7e (if upgraded to IQ software) c. If the customer is running a version lower than 4.7e, or 3.65 ask them if they are interested in this free update, they may get by contacting the GELunar Apps line (USA) or you may order it from GE-Lunar at [email protected] or at 866-225-4771. QUALITY SYSTEM DOCUMENT

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It is the responsibility of the user to verify this document originated from the controlled master and is the active revision prior to use. This document contains confidential or proprietary information of GE Lunar. Neither the document nor the information therein is to be reproduced, distributed, used or disclosed, either in whole or in part, except as specifically authorized by GE Lunar.

GE Medical Systems LUNAR

DOC ID: DXSE0012

REV: G

DATE: 2/28/02

CO: L10173

d. enCORE based systems: i. Contract and Warranty customers are entitled to free software updates (all software versions 6.0 is considered an upgrade and all customers must purchase it) ii. Billable customers may purchase software updates by contacting GE-Lunar at 866-225-4771.

C. SCAN TABLE MAINTENANCE 1. Remove the scanner tabletop. a. Power down the scan table. b. DPX Series tables – unlock the end panel doors and remove the tabletop screws. i. DPX-IQ ii. Non DPX-IQ c. DPX-NT – unlock the end panels and remove the tabletop screws. i. d. PRODIGY – lift up the table pad and remove the 4 counter sunk 1/8” hex head screws in the 4 corners of the tabletop. 2. Clean the scanner interior a. Clean the electronics pan of dust and dirt. b. Wipe the dust and dirt off of the rear longitudinal rail and the transverse rail. 3. Inspect mechanical parts and cables for wear and breakage. a. Check all cables on the cable trough for wear b. Check the v-wheels on the rear longitudinal carriage for appropriate tension Insert V-wheel instructions. 4. X-Ray Generator a. Power up the scan table. b. Ramp the scanner to the appropriate kV / mA and read the test points on the appropriate board as indicated in the X-Ray Settings table on DXSE0038. i. DPX Series 1. Load the version specific diagnostic software from the Tools disk – from a DOS prompt type: A:/diags/diagnos load c:/lunar 2. Enter the diagnostic software – from a C:\LUNAR prompt type: diags 3. Choose option 5 Static Counter QUALITY SYSTEM DOCUMENT

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It is the responsibility of the user to verify this document originated from the controlled master and is the active revision prior to use. This document contains confidential or proprietary information of GE Lunar. Neither the document nor the information therein is to be reproduced, distributed, used or disclosed, either in whole or in part, except as specifically authorized by GE Lunar.

GE Medical Systems LUNAR

DOC ID: DXSE0012

REV: G

DATE: 2/28/02

CO: L10173

ii. EnCORE based systems 1. Place the scanner in Service Mode a. Options / User Options / check the check box for Service – Enter Password (Smile sw ver 1.0 – 2.05 or Award ver 2.10 +) 2. Go to Tools / Diagnostics / Scanner X-ray 3. Enter desired kV and ma – click on ramp NOTE: Be sure to use your anti-static wrist strap when working on or near circuit board assemblies. . 5. Wedge Test (Rollover Test – DPX Series Only) a. Select the Static Counter from the initial menu. When the static counter screen appears, use the arrow key to move the cursor to Operating Voltage, and enter 76.0. b. Move the cursor to Tube Current and enter the number 150. c. Set the "Repeat" number to 20 and the "Printer" to ON. i. If the AGS is operating properly, the low channel counts will be approximately 600,000 to 800,000 counts, and there will be fewer high channel counts in the range of approximately 400,000 to 700,000. Both counts will be stable to approximately +/- 3000 counts from one sample to the next. d. Place the aluminum wedge test tool on the top of the collimator, with the thin edge toward the collimator’s larger aperture, and the thick edge away from the aperture. Insure that the aluminum wedge is NOT in the beam. e. Press and the shutter will open. Allow a 7 samples to appear on the monitor, and then slowly move the Aluminum Wedge through the radiation beam, starting with the thin edge of the wedge. f. Move the wedge very slowly until the beam reaches an aluminum thickness of approximately 2 mm. g. In the results displayed on the monitor, note the sample number where the high channel air counts begin to be reduced. At this point the counts in both channels should be reduced for the following samples. In other words: both the high and low channel counts must decrease consistently as the wedge enters the beam. h. If the low channel counts increase at any point instead of decreasing, the AGS is not properly adjusted or the detector is failing. i. This may cause "bone points" or white pixels in the image around the outside of a patient's Total Body scan and or white streaks in femur scans. QUALITY SYSTEM DOCUMENT

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It is the responsibility of the user to verify this document originated from the controlled master and is the active revision prior to use. This document contains confidential or proprietary information of GE Lunar. Neither the document nor the information therein is to be reproduced, distributed, used or disclosed, either in whole or in part, except as specifically authorized by GE Lunar.

GE Medical Systems LUNAR i.

DOC ID: DXSE0012

REV: G

DATE: 2/28/02

CO: L10173

Run the AGS wedge test and verify that it passes attach results to PM Check sheet.

6. Alignment verification / Mechanical / Cabling check a. Run Air Matrix Scan i. Remove the tabletop if it is on. ii. In DIAGS select F4 QUALITY ASSURANCE TESTS, select option 3 – PERFORM AIR MATRIX SCAN. Choose 1 - Perform A Scan. Change the number of lines to the maximum value, also change the number of steps to the maximum value. iii. Note the filename here_____________________________. This will have to be entered to analyze the data (filename format: XM followed by the 4-digit system number followed by MO.01A. Subsequent scans have extensions 01B, 01C, etc.) Then Press Esc to continue. iv. Remove the detector collimator (non-IQ / MD systems only) and install the Air Matrix Piece (attenuation insert) or tape a 0.25 inch piece of aluminum over the detector (over on top of the collimator) to reduce the intensity of the beam. v. Press Esc to begin the scan. The scan will take approx. 30 minutes to complete. NOTE: If anything passes through the beam during this test, IT WILL FAIL. vi. Analyze the Air Matrix scan in DIAGS by selecting option F4 QUALITY ASSURANCE TESTS then select option 4 ANALIZE AIR MATRIX SCAN. vii. Enter the Air Matrix file name when prompted and press the enter key. viii. All categories must pass, see table 1 for Air Matrix values. Category Limit Chi Squared 45 Skew +/- 0.07 Kurtosis +/- 0.07 Table 1: Failure Limits for the Air Matrix Test ix. Print the overall values by answering Y (yes) when the software prompts x. Return the printout of the passing Air Matrix with the PM Checksheet report (DXSE0038).

QUALITY SYSTEM DOCUMENT

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It is the responsibility of the user to verify this document originated from the controlled master and is the active revision prior to use. This document contains confidential or proprietary information of GE Lunar. Neither the document nor the information therein is to be reproduced, distributed, used or disclosed, either in whole or in part, except as specifically authorized by GE Lunar.

GE Medical Systems LUNAR

DOC ID: DXSE0012

REV: G

DATE: 2/28/02

CO: L10173

xi.

If any categories fail, check the deviation image for possible electronic or alignment problems, consult GE-Lunar OLC for assistance. xii. Run a Daily QA from the system software, or a Peak from the diagnostic software, before trying the Air Matrix. xiii. Once an acceptable Air Matrix scan is printed, delete the Air Matrix files (these files begin with "XM" or "XP" plus the System Number, and they are generally the only files beginning with "X" in the C:\LUNAR subdirectory). b. Beam Wobble scan (Prodigy systems with software version 2.20 and greater DXAP2011) or Alignment scan (Prodigy systems with software versions lower than 2.20 and DPX-NT/MD+ systems- DXAP3001) as appropriate and verify that it passes (attach the results). 7. Limit Switches a. Verify Limit Switch distances (DPX series Diags – F1 Limit Switch Diagnostics / 1 Limit to Limit Distance; enCORE systems - tools / Diagnostics / scanner motion b. DPX Series Only - Home the scanner c. Mark the home position on the Home Jig

QUALITY SYSTEM DOCUMENT

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It is the responsibility of the user to verify this document originated from the controlled master and is the active revision prior to use. This document contains confidential or proprietary information of GE Lunar. Neither the document nor the information therein is to be reproduced, distributed, used or disclosed, either in whole or in part, except as specifically authorized by GE Lunar.

GE Medical Systems LUNAR

DPXIQ / MD180 or DPXα w/ 4.1d or greate r host

DPXL

DPXIQ / MD240 or DPXL w/ 4.1d or greate r host

DPXSF

10920 – 10960

1078010820

1244 01248 0

1243012470

13360 – 13400

1328013320

1988 01992 0

10920 – 10960

1078010820

13360 – 13400 w/ 3.63 host

1328013320

DPXα

(4-3) Transverse Steps

(1-2) Longitudina l Steps

(3-4) Transverse Steps

(2-1) Longitudina l Steps

DOC ID: DXSE0012

REV: G

DATE: 2/28/02

CO: L10173

DPXSF w/ 4.1d or greate r host

PRODIGY

PRODIGY

240cm Table

180cm Table

1092 0– 1096 0

1078010820

12475 +/- 25

12475 +/- 25

12450 +/- 20

12450 +/- 20

1973019770

4225 – 4265

41954235

19890 +/- 35

13790 +/- 35

19605 +/- 20

13530 +/-20

1244 0– 1248 0

1243012470

1092 0– 1096 0

1078010820

12475 +/- 25

12475 +/- 20

12450 +/-20

12450 +/- 20

1988 0– 1992 0 w/ 3.63 host

1973019770

4225 4265 w/ 3.63 host

41954235

19890 +/- 35

13790 +/- 35

19605 +/- 20

13530 +/- 20

DPXNT / MD+ 240c m Table

DPXNT/MD+ 180cm Table

8. Replace the table top and screw down. a. DPX Series Only – Insure Home position is correct by using the Home Jig b. If necessary adjust limit switches 9. Daily QA Tests a. DPX Series only – check the peak setting on the QA last run i. If peak is not 500 +/- 25 units adjust the peak 1. The voltage to the detector is controlled by the adjustment of the potentiometer on the SBC board labeled HV ADJ - R43. 2. The voltage at TP18 of the SBC is equal to the detector voltage divided by 1000. If R43 is adjusted to decrease the voltage at TP18 by 0.001, the peak will increase by 5 units. 3. The last peak value obtained during a Quality Assurance scan is stored in the Quality Assurance History database file. QUALITY SYSTEM DOCUMENT

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It is the responsibility of the user to verify this document originated from the controlled master and is the active revision prior to use. This document contains confidential or proprietary information of GE Lunar. Neither the document nor the information therein is to be reproduced, distributed, used or disclosed, either in whole or in part, except as specifically authorized by GE Lunar.

GE Medical Systems LUNAR

DOC ID: DXSE0012

REV: G

DATE: 2/28/02

CO: L10173

If the next peak value obtained differs from the last value stored in the database by more than 50 units, the Quality Assurance scan will fail. If the peak must be shifted by more than 50 units to return it to 500 units +25, the peak must be adjusted in steps of less than 50 units (40 unit steps are recommended). 4. A complete QA must be run 5. between each step to update the Quality Assurance History database file. 6. If the software peak setting corresponds to where both the high and low channel counts are at a maximum, (see fig. 6.3) follow the steps outlined below. The graph on the QA will look similar to the one shown in fig 6.3 with the dashed vertical line (where the software thinks the peak is) on the graph at a point where both the high and low energy plots are maximized (the dashed curved lines). If the graph on the QA is unlike fig 6.3, go to part B of this procedure. 7. select "Peak / Set AMP Gain", then select "Perform Peak" and [Esc] to run the peak. Observe the results generated by the QA to determine if the software has selected the Amplifier Setting where both high and low channel counts are at a maximum. If not go to part B. 8. 3. If the peak requires adjustment, (is not within +/- 25 units of 500) connect a voltage meter to the SBC at TP18 (see fig 6.2). Put the meter to the VDC scale and record the voltage reading (e.g. 0.703VDC 9. Using the voltage recorded in step 3 and the peak value recorded in step 2 determine the appropriate voltage adjustment for R43. 10. To determine voltage adjustment: a. If Peak >500: /5 * + Old VTP18

New

VTP18

= (Current Peak – 500)

b. Peak