FDA has cleared a modified version of the Monteris Medical NeuroBlate probe designed to eliminate the unintended heating problem that triggered a Class I recall and posed a possible risk to brain tissue.
The agency alerted healthcare professionals to dangers related to the neurosurgical ablation device and a rival product from Medtronic earlier this year after receiving reports of adverse events that may have stemmed from inaccurate temperature readings.
Monteris responded to cases of unintended heating by replacing the metallic thermocouple temperature sensor found in its original device with a non-metallic fiber optic sensor.
Magnetic resonance-guided laser interstitial thermal therapy is a delicate procedure that can yield positive outcomes in hard-to-treat populations, such as patients with certain forms of brain cancer. A laser probe is placed into the tumor or other tissue that needs to be ablated. Once in place, the laser emits energy to heat up and kill the targeted tissue while surgeons monitor its effects in real time.
In April, FDA reported doubts about the accuracy of the magnetic resonance thermometry readings surgeons use to monitor the procedure. FDA was concerned parameters such as image resolution and capture time were contributing to inaccurate readings, and devices were failing to factor in the fact the thermal energy can continue to spread to surrounding tissues even as the target area cools.
Monteris has redesigned its device in response to the concerns. FDA cleared a premarket submission of the modified device and is advising healthcare professionals to contact Monteris to find out when it will be available.
In the meantime, FDA wants healthcare providers to consider the risks and alternatives before using the old metallic probe. FDA reiterated Thursday the recommendations it issued in April, which are designed to mitigate the risk of harm by capping the maximum temperature and taking other precautions.
FDA also maintained its advice to users of Medtronic's Visualase Thermal Therapy System. Medtronic initiated a recall of the device in June and sent three advisory letters to healthcare professionals over the summer. The letters detailed strategies for mitigating the risks posed by the system, which Medtronic acquired in its $105 million cash takeover of Visualase in 2014.
Visualase gained FDA clearance before the agency signed off on Monteris' rival device, and has benefited from the marketing might of Medtronic for the past few years. That stacked the odds against Monteris but the recent recall-triggered revisions have given it a new angle in the fight for market share. Monteris now highlights its use of fiber optics as differentiator.