Intraoperative scintigraphy in surgical treatment of thyroid carcinoma: evaluation of a new technique.

Abstract

AbstractEven when thyroidectomy with lymphadenectomy for thyroid carcinoma is macroscopic‐ally radical, postoperative scintigraphy sometimes reveals iodine uptake in residual or ectopic thyroid tissue or lymph nodes, necessitating radioiodine ablation. In order to detect such tissue during the operation, a technique for intraoperative scintigraphy was devised. It was tested in 20 patients undergoing total thyroidectomy for highly differentiated thyroid carcinoma. The patients received 20 mBq125I intravenously 24 hours before the operation. After removal of all macroscopically visible thyroid tissue and metastatic growth, the operative field was examined with a cadmium‐telluride detector placed in a sterile tube of stainless steel. By using this technique, iodine uptake was found in 16 of the 20 patients. All of this tissue was removed in 11 patients, leading to a negative postoperative scintiscan in 9 patients. In 2 patients, the perioperative scanning identified minimal residual uptake in a minute remnant of thyroid tissue adjoining the nerve entrance and not requiring postoperative radioiodine ablation. Scintigraphy was repeated in all patients 6 weeks after thyroidectomy. Recordings over different‐sized tissue fragments showed the detector to have a very high sensitivity, with capacity to detect tissue fragments weighing less than 2 mg. The results indicate that intraoperative scintigraphy, according to this technique, increases the possibilities to perform a complete removal of thyroid and tumor tissue and significantly reduces the need of postoperative radioiodine ablation.