Preoperative ultrasound and thallium-technetium subtraction scintigraphy in localizing parathyroid lesions in patients with hyperparathyroidism.

Clinical and biochemical evaluation of patients with hypercalcemia are today extremely accurate in identifying those with primary hyperparathyroidism. Neck exploration by an experienced parathyroid surgeon is equally likely to identify correctly the diseased gland or glands. It has been suggested that recently devised localization techniques may allow the surgeon to limit the extent of the procedure to one side of the neck. The present retrospective study was undertaken to determine the reliability with which two such imaging procedures, ultrasonography (US) and thallium-technetium subtraction scanning (TTSS) localize these lesions by specific site or side. The identity of each patient undergoing parathyroidectomy at a metropolitan medical center was determined by review of the operating room log. From the records of each subject were noted the results of any imaging studies done, the location of lesions found at surgery, and the histologic diagnosis. Accuracy and positive predictive value of US and TTSS were then calculated on the basis of precise and lateralizing localization. Seventy-four patients underwent primary neck exploration during the study period. In 69 patients US, TTSS, or both were performed preoperatively, and among these, data were complete in 65. Ultrasound correctly localized the site of a lesion in 31 of 63 subjects, and TTSS in 25 of 45. Ultrasound correctly localized the side on which the lesion lay in 35 of 62 subjects, and TTSS in 27 of 45. In 29 of 42, one or both studies correctly identified the side on which the lesion lay. In only one of 13 subjects with hyperplasia were all four glands correctly identified as hyperplastic.(ABSTRACT TRUNCATED AT 250 WORDS)