Parathyroid identification by methylene blue infusion.

A preoperative infusion of methylene blue was employed in 20 patients undergoing neck exploration for hyperparathyroidism. The dye was noted to stain adenomas and hyperplastic glands a deep purple-blue colour. Normal parathyroid tissue stained to a lesser extent or not at all. All unstained parathyroid tissue was normal histologically. Methylene blue infusion is a safe method of more rapidly identifying parathyroid tissue. Its preferential staining of abnormal parathyroid tissue can assist the surgeon in deciding the extent of his parathyroid excision.