SIGNA MR355 / SIGNA MR360
Service Manual
5856356-3EN Revision 5.0
Basic Service Documentation. Copyright General Electric Company.
Object ID: 00000018WIA30BAAF20GYZ
Topic ID: id_13107173 Version: 1.9
Date: Jul 6, 2019 12:03:28 AM

System Gain Head Calibration

Prerequisites

Table 1. Personnel requirements
Required persons	Preliminary requirements	Procedure	Finalization
1	Not Applicable	20 minutes	10 minutes

Table 2. Tools and test equipment
Item	Quantity	Effectivity	Part number	Manufacturer
NiCl TLT Head Sphere	1	-	46-265826G6	-

Table 3. Safety

Warning

POISON HAZARD!

1.5T, 1.0T, and 0.7T PHANTOMs CONTAINS NICKEL, A SUSPECTED CARCINOGEN.

DO NOT INGEST. DISPOSE OF AS A HAZARDOUS WASTE ACCORDING TO STATE AND FEDERAL REGULATIONS.

Warning

Poison Hazard!

3.0T phantoms contain dimethyl Silicone Fluid. Do Not ingest.

If Lead or spill occurs, wipe up or absorb in inert material and place in a container for disposal. Incineration or landfill is the recommended disposal method.

Table 4. Required conditions
Condition	Reference	Effectivity
Signa software is fully operational.	-	-
Gradient Calibration is completed.	-	-
No image artifacts are present.	-	-
System should be set to the English language.	-	-

Head System Gain Calibration

Procedure

For systems with the new Split-Top Head Coil, position the SNR Sphere in the head loader as shown.

Figure 1. Positioning SNR Sphere in Head Loader
Fasten the strap to the top of the Head Loader to secure the SNR Sphere in the loader. Position the head loader on top of the Head TLT Loader Holder in the head coil (as shown), so the loader is centered and the loader axial mark is at the center of the head coil window.

Figure 2. Landmarking Head SNR Sphere
For systems with the Quad Head Coil, position the DQA Phantom in the head coil.
1. Turn on the alignment lights, and align so the center of the DQA Phantom matches the axial beam.
2. Place the Head TLT Sphere in the Head Loader, and fasten the strap to the top of the loader to secure the sphere.
3. Remove the DQA Phantom and replace with the Head Loader/Sphere, centering it using the axial alignment lights.
At the keypad on the front of the magnet enclosure, press Landmark and Move to Scan.
Go to the Service Desktop and start the Service Browser if not already running. Start the System Gain Calibration as shown below.

Figure 3. Starting System Gain Tool
After the tool starts, type 2 and press Enter for Auto Mode shown below.

Figure 4. Selecting Auto Mode
Type 1 and press Enter for Manual Mode to begin the test.
Figure 5. Selecting Head Mode

When testing is completed, one of two responses will display:
- One will indicate the calibration is done and no adjustments are required.
- The other message will ask if the new Recon Scale Factor should be saved. Type Y and press Enter to save the new calibration file.
Figure 6. Calibration Output
When finished, type 4 and press Enter to exit the tool.

Finalization

Procedure

Remove all phantoms from the system.
Perform a check scan to ensure system operation.