Assessing Intraoperative Laser Speckle Contrast Imaging of Parathyroid Glands in Relation to Thyroidectomy Patient Outcomes.

Abstract

BACKGROUND\nAccurate assessment of parathyroid gland vascularity is important during thyroidectomy to preserve the function of parathyroid glands and prevent postoperative hypocalcemia. Laser speckle contrast imaging (LSCI) has been shown to be accurate in detecting differences in parathyroid vascularity. In this surgeon-blinded prognostic study, we evaluate the relationship between intraoperative LSCI measurements and postoperative outcomes of thyroidectomy patients.\n\n\nMETHODS\nEighty-one thyroidectomy patients were included in this study. After thyroid resection, an LSCI device was used to image all parathyroid glands identified, and a speckle contrast value was calculated for each. An average value was calculated for each patient and the data was grouped according to whether the patient had normal (16-77 pg/mL) or low levels of parathyroid hormone (PTH) measured on postoperative day 1. The aim of this study was to establish a speckle contrast threshold for classifying a parathyroid gland as adequately perfused, and to determine how many such glands are required for normal postoperative parathyroid function.\n\n\nRESULTS\nA speckle contrast threshold was identified that separated the normoparathyroid and hypoparathyroid groups with 90% sensitivity and 82.8% specificity. Taking this value as the threshold for adequate parathyroid perfusion, it was determined that only one vascularized gland was needed for normal postoperative parathyroid function: 91.4% of patients with at least one vascularized gland (determined by LSCI) had normal postoperative PTH, while 100% of patients with no vascularized glands had low postoperative PTH. Overall, the rates of temporary and permanent hypoparathyroidism in this study were 10.8% and 1.4% respectively.\n\n\nCONCLUSION\nLaser speckle contrast imaging is a promising technique for assessing parathyroid gland vascularity. It has the potential to help reduce the incidence of hypocalcemia after thyroidectomy by providing surgeons with additional information during surgery to aid in the preservation of parathyroid function.