Postsurgical hypoparathyroidism or hypocalcemia are known to frequently occur after all thyroid surgeries due to misidentification and/or accidental disruption of the blood supply to the healthy parathyroid glands. Such accidental removal or injury of the parathyroid glands may lead to complications that result in lifelong sequelae. Because of the small size, variable position, and similar appearance to the surrounding tissues such as the lymph node, fat, and thyroid gland, it is often difficult for low-volume surgeons to distinguish the parathyroid glands from the thyroid tissue. Furthermore, blood supply to the parathyroid glands is fragile and can be easily damaged during dissection. This is a challenging problem because it is clinically difficult to tell by visual inspection if a gland is still viable after manipulation. Currently, there is no standardized or practical equipment available to localize and assess the parathyroid gland viability in real time and in a noninvasive manner during operation. Thus, any viable solution would be considered significant to the endocrine community. In this study, to address these unmet clinical needs, we propose to develop a noninvasive, dual- sensor RGB/NIR handheld imager that will potentially be a paradigm changing tool for patients with thyroid tumors. Our imaging solution, called hANDY-i™, permits 1) noninvasive parathyroid gland identification and 2) seamless display of tissue viability in real time for the preservation of the parathyroid glands during thyroid surgery. This research will be a joint effort combining the technical and clinical expertise of Optosurgical LLC and Johns Hopkins Hospital. To test this hypothesis, we will study the following specific aims: Aim1: To characterize and deliver a compact, operating room-ready hANDY-i device; and Aim 2: To validate hANDY-i to identify the parathyroid glands and assess viability in an early feasibility study (N=10). Upon successful completion of this SBIR Phase I project, we will proceed to the Phase II project, wherein we will engineer a commercial-grade version of the hANDY-i device and execute large-scale multicenter clinical trials. We envision that our technology will open a new door for the digital imaging paradigm of dye-free, temporally unlimited, and quantitative tissue perfusion assessment. Successful translation of this technology will potentially reduce the risk of hypoparathyroidism during thyroid surgery and improve clinical outcomes.