MON-115 Inappropriate Ordering of Parathyroid Scintigraphy in an Academic Medical Center

Abstract Introduction: The diagnosis of primary hyperparathyroidism is a biochemical, not radiologic one. Unfortunately, many practitioners even in academic centers order parathyroid scintigraphy to “confirm a diagnosis of adenoma” or distinguish primary from secondary hyperparathyroidism. Knowing the location of single or multiple parathyroid adenomas is unnecessary unless parathyroidectomy is planned. The financial burden of nuclear imaging is substantial. The goals of this study were to determine the proportion of inappropriately ordered parathyroid scans and the cost to the health care system. Methods: We generated a database of patients who had consulted with at least one physician at our institution and underwent parathyroid scan between December 2012 and December 2017. We focused on the subset that did not undergo parathyroidectomy. “Slicer dicer” software in our EMR was used to generate the database. Chart review extracted data on diagnoses and reasons for parathyroid scintigraphy. Results: Over 5 years, a total of 325 parathyroid scans were performed. 171 of these did not have parathyroidectomy in our system. However, 18 underwent surgery elsewhere leaving 153 that received parathyroid scans but no surgery (47% of the total). Of the 91 cases so far analyzed of the 153 in our database, average age is 64, with 28 males and 63 females. 61 of the 91 scans (67%) were performed to confirm the diagnosis of parathyroid adenoma; 3 performed because of possible parathyroid adenoma seen on other imaging; and 24 (26%) were done supposedly to localize the adenoma for surgery. Ordering physicians were from primary care (41%), endocrinology (26%), nephrology (18%), and surgery (10%). Final diagnoses for these 91 patients were true primary hyperparathyroidism in 37 (41%), secondary hyperparathyroidism in 38 (42%), unclear in 10 and FHH in 4. In the primary hyperparathyroidism group, 19/37 met criteria for consideration of parathyroidectomy, but only 5/19 received surgical consultation. These 5 patients either refused surgery or surgeon decided against, usually because of high surgical risk. Conclusion: 47% of parathyroid scans at an academic institution were performed in patients who did not undergo parathyroidectomy. Many parathyroid scans were ordered inappropriately to “confirm” a diagnosis of primary hyperparathyroidism, leading to unnecessary charges and resource waste. Physician charges for sestamibi scans range from $237-$1942, depending on whether planar imaging, SPECT, or SPECT-CT is used; hospital charges are $1165-$3211. We propose to change the ordering system for parathyroid imaging to clarify that this is not a method to diagnose parathyroid adenoma, rather a tool to optimize surgical planning when the diagnosis is secure.