On this page
Asset Type
Manufacturer
Model
What This Guide Helps With
Troubleshooting collimator recognition, seating, lock, exchange, or detector setup issues before repair escalation.
Step-by-Step Troubleshooting
Ensure Patient Safety First
Confirm the Symbia Evo is not actively being used for a patient study.
If the issue occurs during patient setup, stop the exam workflow and move the patient away from the detector, table, gantry, and collimator area before troubleshooting.
Expected outcome: No patient is positioned near moving or improperly seated collimator components.
Confirm the Exact Collimator Complaint
Ask the operator what happened during setup or exchange.
Determine whether the issue involves:
- Collimator not recognized
- Wrong collimator displayed
- Collimator appears seated but system reports an error
- Collimator exchange will not complete
- Collimator lock or latch concern
- Detector head reports a collimator mismatch
- Error occurs with one specific collimator or multiple collimators
- Issue occurs on one detector head or both
Expected outcome: The fault is narrowed to recognition, seating, locking, workflow, or a specific collimator.
Verify the Correct Collimator Is Being Used
Confirm the collimator installed matches the intended protocol and detector configuration.
Check that the collimator type selected or expected by the acquisition protocol matches the physical collimator installed.
Expected outcome: The system and physical setup agree on the required collimator type.
If the wrong collimator was installed or selected, correct the setup, repeat recognition, and stop if the issue is resolved.
Inspect the Collimator Seating Externally
Visually confirm the collimator is fully seated and evenly positioned on the detector head.
Look for obvious gaps, uneven alignment, foreign material, obstruction, or anything preventing full seating.
Do not place hands near pinch points or attempt to force the collimator into position.
Expected outcome: The collimator appears mechanically seated, aligned, and unobstructed.
Check Collimator Lock or Latch Status
Verify the collimator locking mechanism appears fully engaged according to normal user workflow.
If the system reports the collimator is unlocked or not seated, have trained Nuclear Medicine staff repeat the normal seating or exchange process.
Expected outcome: The system recognizes the collimator as seated and locked after a normal, safe exchange attempt.
If recognition returns after reseating, document the issue and stop.
Check for Obvious Physical Damage
Inspect the collimator exterior, mounting surfaces, visible identification area, and detector-side seating area for damage.
Look for bent edges, chipped surfaces, loose hardware, damaged labels, cracked covers, or signs the collimator was dropped.
Expected outcome: No visible physical damage is found that would interfere with seating or recognition.
If damage is found, remove the affected collimator from use and escalate for evaluation.
Confirm the Issue Does Not Follow One Collimator
If safe and allowed by site policy, compare with another approved collimator of the correct type.
Determine whether the fault follows the same collimator or remains with the detector head or exchange position.
Expected outcome: The issue is isolated to either a specific collimator or the system recognition/seating path.
If only one collimator fails, remove that collimator from service and label it for repair evaluation.
Confirm the Issue Does Not Follow One Detector Head
If the system has multiple detector heads, determine whether the recognition fault occurs on one head or both.
A single-head failure may suggest a detector-side recognition, seating, sensor, or lock detection issue.
Expected outcome: The affected detector head or recognition location is identified.
Check for Workflow or Software State Issues
Confirm the system is not mid-protocol, mid-exchange, or in a partially completed acquisition setup.
Return to a safe home/setup state if permitted by normal operator workflow, then attempt recognition again.
Expected outcome: The system is in the correct state to recognize the installed collimator.
If the issue clears after returning to the correct setup state, document the workflow condition and stop.
Review System Messages and Event Details
Record the exact error message, detector head involved, collimator type, protocol selected, and when the message appears.
Note whether the error appears during startup, exchange, protocol selection, detector positioning, or acquisition setup.
Expected outcome: Clear fault details are available for repair escalation if needed.
Power Cycle Only When Safe and Appropriate
If no patient is present and the department agrees, perform a controlled system restart using approved site workflow.
Do not power cycle during an active acquisition or while the system is in an unsafe mechanical state.
Expected outcome: Temporary software recognition issues are cleared without creating a mechanical or patient safety hazard.
If the collimator is recognized after restart, verify operation with the department and document the action taken.
Do Not Force Movement or Exchange
If the collimator will not seat, release, lock, or be recognized after normal external checks, stop troubleshooting.
Forcing a collimator or repeating failed exchange attempts can create equipment damage and staff safety risk.
Expected outcome: Troubleshooting stops before unsafe mechanical intervention occurs.
If the Problem Persists
If the collimator is still not recognized, will not seat correctly, will not lock, or the exchange process repeatedly fails, common external causes have been ruled out.
The Symbia Evo or affected collimator should be:
- Removed from clinical use
- Labeled Out of Service
- Prevented from being used for patient imaging
- Sent for repair or bench evaluation by qualified service personnel
Knowing when to stop is proper troubleshooting. Collimator seating and recognition issues involve mechanical safety, detector alignment, and image quality, so unresolved faults should not be worked around.
Clinical Use Tip
Do not troubleshoot a collimator seating or exchange issue with a patient on the table or positioned near the detector heads. Move the patient away first, then investigate the system only when the gantry, detector, table, and collimator area are safe.
Do not troubleshoot on an active patient. Move the patient to a backup device first when needed to maintain therapy continuity.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
"Nuclear Medicine reported the Symbia Evo would not recognize the installed collimator during exam setup."
Cause
What was observed during troubleshooting.
Example:
"Verified the correct protocol was selected, reseated the collimator, and found the recognition fault followed one specific collimator."
Resolution
What action was taken.
Example:
"Removed the affected collimator from service, labeled it Out of Service, documented the error behavior, and escalated for repair evaluation."
Helpful Details to Include (If Known)
- Collimator type installed
- Detector head involved
- Whether issue affected one collimator or multiple collimators
- Whether issue affected one detector head or both
- Exact error message displayed
- Alarm behavior
- Accessories swapped
- Power behavior
- Environmental factors
- Indicator lights
- Whether collimator appeared fully seated
- Lock or latch status
- Any visible damage
- Whether the issue occurred after recent exchange, cleaning, or service
- Whether restart changed the behavior
- Final device and collimator status
Final Thought
Collimator troubleshooting should always protect patient safety first, then follow a logical path through protocol selection, seating, lock status, visible damage, and recognition behavior. If the issue cannot be resolved with safe external checks, escalation is the correct response. Accurate CCR documentation helps service identify whether the fault is collimator-specific, detector-specific, or workflow-related.
That is successful troubleshooting.