As much as 50% of thyroid procedures result in post-surgical hypoparathyroidism and consequent hypocalcemia. This can be due to accidental removal of the parathyroid glands or damage to their blood supply that renders them non-viable. The parathyroids are the body’s main organs for regulating calcium, so loss of their function will require lifelong medication to maintain normal calcium levels. Work has been done separately to address both causes of parathyroid function loss. Autofluorescence spectroscopy/imaging has been shown to be highly accurate in distinguishing parathyroid glands from other tissues in the neck, helping avoid accidental removal of parathyroid glands. Laser speckle contrast imaging (LSCI) is capable of accurately identifying parathyroid glands that have suffered vascular compromise, providing guidance on whether to transplant a parathyroid. Here, we present an instrument that combines both techniques to enable parathyroid identification and viability assessment. Additionally, we developed algorithms to automate the extraction of parathyroid viability information from speckle contrast images using information from fluorescence images. This makes the device more autonomous and speeds up the process of providing information to the surgeon. Testing on ex vivo parathyroid and thyroid specimens revealed that the algorithm performs best when the ratio of parathyroid to thyroid fluorescence is at least 1.5. The device will also be tested on patients undergoing parathyroidectomy at Vanderbilt University Medical Center. Autofluorescence data will be validated by histology to confirm parathyroid tissue, and LSCI data will be validated by ligating the blood supply to the diseased parathyroid gland in preparation for removal.
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