Best Clinical Scenarios for Use
While these surgeons agree that the new imaging technologies are a positive disruption, questions remain as to the best situations for their use. This has yet to be defined, said Dr. Pelliterri.
Explore This IssueFebruary 2021
“Right now, I think this technology’s greatest utility is for identifying the parathyroid glands during thyroidectomy,” he said, adding that ICG, which is tracer-dependent, may have a place in parathyroid re-exploration surgery, while autofluorescence may be of use during abnormal parathyroid gland surgery. “As experience is gained in using these for parathyroid exploration, the technology will improve. The initial efforts were quite clunky and difficult to use in the operating room. Now, they’re more streamlined and efficient to use to identify the glands, to secure the identification with autofluorescence, and to protect the parathyroid glands during the removal of the thyroid.”
Dr. Zafereo has used autofluorescence devices in about 75 surgical cases so far, and while it does fluoresce most normal parathyroid glands, challenges remain for its use in standard clinical practice, “including a lot of false-positive fluorescence associated with cancerous lymph nodes, brown fat, or other artifacts, as well as the need to turn off the surgical lights in order to use the device, which slows down the surgery.” For the most challenging cases, patients with significant nodal metastases, autofluorescence imaging isn’t as useful due to the significant levels of false positive fluorescence, he said.
Dr. Terris suggested combining both imaging techniques, using an autofluorescence device to identify the parathyroid glands and ICG to sense blood flow to them through tiny vessels that may look intact to the naked eye, but can be easily damaged during surgery. He added that that these imaging devices may be most useful for surgeons who perform a low volume of procedures because they’re less comfortable distinguishing these tissues due to limited experience.
Dr. Pellitteri agreed. “Autofluorescence systems may give less-experienced surgeons more confidence to achieve successful parathyroid surgery, and it may also play a useful role in surgical training,” he said. “ICG also has some potential toxicity risk, which is eliminated entirely in autofluorescence technologies. While ICG has a role, as autofluorescence improves, I think it will probably become the pre-eminent modality.”
Susan Bernstein is a freelance medical writer based in Georgia.