Table 2.
Common sources that impact the reliability of the MRI subsystem.
| Source | Mechanism | Manifestation | Frequency per system | Typical return to service time |
|---|---|---|---|---|
| Torso RF Coils | Broken components | Signal loss, image noise or artifact | 6/yr | <30 min† |
| MRI RTC disconnects | Communications issues | Loss of communications halts operations | <2/month | <30 min |
| MRI‐GO | Real time feedback | Software disconnects between subsystems | <3/month | <30 min* |
| Patient table | Sensor failure | Table error halts operations | <1/month | SW: <30 minHW: <1.5 days |
| MLC failure | Stuck MLC | MLC error halts operations | <2/month | <30 min |
| Gantry | Sensor failure | Rotation error halts operations | <3/yr | SW: 20 minHW: <1.5 days |
| 60Co | Delivery errors | Software and source errors halt operations | <2/month | <45 min |
| Linac | Delivery errors | Software errors halt operations | <6/month | <45 min |
MLC: Multi‐leaf collimator, RTC: Radiation therapy control. Return to service times depend on software version and assume a field service engineer is present on site. SW: software repair (e.g., system reboot). HW: hardware repair (e.g., part replacement).
*
Return to service times have decreased since April 2019 software patch installation.
†
Assumes spare RF coil is available on site, otherwise ~1 day.