The FDA is warning of the risk that frameless stereotactic navigation systems, used to plan and conduct ear, nose & throat, brain and facial surgeries, might not be accurate if not used properly.
Stereotactic navigation uses computed tomography or magnetic resonance imaging scans to generate a “map” surgeons use to guide their instruments. Some systems use frame that’s fixed to the patient with screws or pins to orient the device, but the more common frameless systems do not.
The federal safety watchdog said it’s received reports of “navigational accuracy errors” during surgeries using the frameless devices.
“Some of these errors have led to patient deaths, serious or life-threatening injuries, and inaccurate, aborted, or prolonged medical procedures,” the FDA said. “Based on our analysis, the FDA believes that there are many factors that contribute to these errors, and no particular system carries greater risk than others.”
The safety bureau’s review of data revealed that the errors stem from a variety of causes, including:
- Navigation Software and Hardware, including software anomalies and hardware damage or defects;
- System Complexity (Human Factors), including use errors in inputs, system setup and execution of system and surgical techniques;
- Compatibility, including the use of incompatible accessory instruments with the stereotaxic navigation system;
- Anatomical Complexity, including surgical requirements and intraoperative shift (e.g., brain shift, local tissue deformation from tissue resection, spinal movement);
- Registration & Tracking, including poor registration and movement of the registration fiducials or reference array; and
- Medical Image Quality, including insufficient image resolution and incomplete images.
Although the FDA said it still believes that the benefits of frameless stereotactic navigation devices outweigh the risks, “in appropriately selected patients when used by properly trained surgeons,” physicians should take a number of precautions when using the devices.
“The FDA is working with device manufacturers to ensure accurate labeling that includes clear user instructions on how to minimize the occurrence of these issues,” the agency said.