With real-time autofluorescence, you have the advantage of looking and working at the same time, and this expedites the procedure. It’s a smoother, more efficient evaluation. —Phillip K. Pellitteri, DO
Explore This IssueFebruary 2021
The goal of faster surgery is a lower rate of complications, said Dr. Pellitteri. “We want to preoperatively or intraoperatively identify abnormal parathyroid tissue so it can be targeted in the operating room and removed. One scenario [for its use] is when parathyroid surgery has to be repeated, and there is re-emergence of hypocalcemia. You’re at the best advantage when you target those glands and remove them with as little disturbance as possible.”
Near-Infrared Systems: Pros and Cons
Currently, there are two devices based on autofluorescence in the near-infrared spectrum approved by the FDA to identify parathyroid tissue during surgery: the Parathyroid Detection PTEye System, manufactured by AIBiomed Inc. in Santa Barbara, and Fluobeam, manufactured by Fluoptics in France. Dr. Terris believes that this is “a disruptive, meaningful new technology that will improve outcomes,” is more practical to use than ICG, and eliminates the need to inject any dyes.
PTEye is “almost like a Geiger counter. You hold it up to the tissues, and if the tissue is parathyroid, the number will be very high. It works very well and is best used for tissue verification,” he said. “You want to preserve the glands. You don’t want to overlook them or mistake them for fat. Sometimes, we’ll send a frozen section to the lab during the operation, but that’s time consuming.” PTEye eliminates the need for this step, he noted. Fluobeam consists of a device aimed into the wound that quickly causes the parathyroids to appear white when compared to nearby tissues, said Dr. Terris. “Anything that isn’t parathyroid, such as muscle or fat, looks sort of dark gray. We want to accurately identify the parathyroids if we can, so we can dissect them away from the thyroid and preserve them.” These devices could also be useful as a way to scan a removed thyroid to identify if any parathyroid tissue was accidentally taken out with it, allowing surgeons to re-implant it during the procedure, he noted.
Before the COVID-19 pandemic, Dr. Stack traveled to Geneva, Switzerland, to train on both PTEye and Fluobeam systems. He believes that as these devices are used by more surgeons in the coming years, the technology will be modified and improved by manufacturers.
“Fluobeam provides a more panoramic visual identification, while PTEye uses an auditory signal and a numerical display,” said Dr. Stack. Both he and Dr. Terris said that Fluobeam would be easier to use during surgery if the light source and camera were smaller in diameter and gave this feedback to manufacturers. “If the parathyroid gland is more than 1-2 millimeters within the tissue, you may not get enough exposure of light from the Fluobeam, and it won’t stimulate parathyroid autofluorescence.”