Scanner troubleshooting

• I was scanning successfully and after saving a regular series I was unable to perform “Prepare to Scan” as the button was disabled (grayed out). How should I proceed?
• The scanner reports an error "prescription not accepted" and fails after running a prep scan. What do I do?
• The Paradigm Manager has crashed again! What do I do?
• While scanning the host computer froze. Should I reboot the host computer?
• While scanning a warning “patient comfort level exceeded” shows up in the upper-left error message window. How should I proceed?
• How do I perform TPS reset?
• What happened to the dynamic_EPI_constant resetting?
• Why the patient table becomes sometimes unresponsive when moved out of the scanner bore?
• The console computer is running very slowly when reconstructing images! What's up with that?

• I was scanning successfully and after saving a regular series I was unable to perform “Prepare to Scan” as the button was disabled (grayed out), or  the BrainWaveRT window was not displayed. How should I proceed?
  

It is advisable to perform TPS reset before each exam. This may fix some of GE GUI problems.
If BrainWave is causing too much trouble it is advisable to bypass it and use Research option in the fMRI Screen. 
Otherwise try the following tricks: (i) make sure the BrainWave RT window is closed (the most common reason for inability to continue with a scan following a fMRI scan); (ii) start with a fresh (after copying and pasting series) series; (iii) as the last resort perform TPS reset. Then select Instruments Desktop, and press TPS reset button. Confirm the operation. TPS reset takes ~2 min to complete. Then press New Pt button, and start a new exam. Using mr command in the patient field brings back subject information of the previous exam and in most cases restores previous landmark, so that no new landmark (which involves moving the patient table out to the landmark position) is needed. A new localizer is necessary in order to proceed with the study.

•  The scanner reports an error "prescription not accepted" and fails after running a prep scan. What do I do?

The error occurs when the hard disk is full. Check the disk space. It is reported in the upper left corner of the GE GUI. If it the disk is over 80% full, switch to the exam browser desktop, and delete a few oldest exams (select oldest exams in the browser, and click on remove button) until the disk is less than 50% full.  

•  The Paradigm Manager has crashed again! What do I do?

If you're fed up with buggy BrainWave+Paradigm Manager software, select Research option in the fMRI screen, which allows to bypass both. Otherwise, some solutions are provided in the document Using and Restarting the Paradigm Manager

• While scanning the host computer froze. What should I do???

If the host computer stops responding the program controlling the GE scanner can be restarted by rebooting the Linux. Select restart on the popup sub-menu that can be accessed by pressing the right mouse button on empty desktop space and selecting Service Tools. If there's no response to mouse clicks, open the PC container door and press the power button on the Linux Workstation.

• While scanning a warning “patient comfort level exceeded” shows up in the upper-left error message window. How should I proceed?

This warning indicates that the scanner bore temperature has reached 30 degrees  due to the heating generated by the rapid switching of currents in gradient coils. The highest rate of gradient switching occurs while running functional EPI pulse sequence with many slices (e.g. 16/sec) and using high bandwidth (e.g. 125 KHz ).  If the bore temprature reaches 34 degrees, the scanner will stop and at least 30mins is required for the scanner to return back to the operational state.
Therefore, when you see the "patient comfort level" warning, it is recommended to insert small gaps (~ 5 minutes) in between scans or intealeve lower gradient switching scans (such as structural) with the high gradient-switching scans.

• How do I perform TPS reset?

It is advisable to perform TPS reset before each exam. This may fix some of GE GUI problems.
In case you need to reset TPS, Press <TPS Reset> button on the Tools desktop. It takes less than 2 min to complete it. Then start a new exam and in the Patient ID field type mr (Most Recent) and press <Enter>. This will recover information about previous exam. In addition, in most cases it would also recover previous landmark.  However, occasionally the scanner will refuse to scan and demand a new landmark, in which case move the patient out by using Back to Landmark button (blue with an arrow out and a zero on top). This way the old table position will be preserved. Run a new localizer. In order to carry over previous prescriptions it is necessary to write down prescription parameters (LR, AP, IS positions, # slices, FOV etc) - then they can be entered manually.

• What happened to the dynamic_EPI_constant resetting?

After GE updated their software, this constant no longer helps with ghosting.

• The console computer is running very slowly when reconstructing images!???

This occurs when some exams are queued for network transfer over DICOM server. The queue simply needs to be cleared by going to the Network desktop, selecting  Queue->Network, and remove all entries in the queue.
If that does not help, a problem report should be filed since in this case the DICOM database needs to be reset by Center's presonnel.

• · Why the patient table becomes sometimes unresponsive when moved out of the scanner bore?

The table control mechanism
Usually this occurs if the table fails to completely reach the end of the gurney. In that case pull the table completely to the end of the gurney. In addition it may be necessary to press TWICE a blue (table motion) button on the panel above the scanner bore in order to make the table to respond.