INTRAOPERATIVE PARATHYROID LOCALIZATION I N PRIMARY HYPERPARATHYROIDISM BY METHYLENE-BLUE GIVEN PREOPERATIVELY

Is surgery for primary hyperparathyroidism easier when methylene blue (MB) is given preoperatively? This retrospective study compares the du rations of interventions for primary hyperparathyroidism carried out a fter iv MB administration to those when no MB was given. Over a period of 20 years (June 1976 to December 1996), 175 consecutive patients (5 6 men and 119 women, with ages ranging from 16 to 92, mean 59.6) were operated upon for primary hyperparathyroidism; 55 were operated before February 1986 - the period when BM was introduced routinely, and 120 after. Thirty-two other patients were excluded from the study: 14 had had a previous cervicotomy and 18 another procedure in addition to the parathyroidectomy (usually on the thyroid gland), two conditions whic h prolonged the time devoted to parathyroid identification and excisio n. Preoperative calcemia averaged 2.97 mmol/L (2.34 to 4.59) and mean preoperative PTH was equal to 2.6 times the upper normal limit (0.5 to 24.1). Both groups were similar for as age, sex, preoperative calcium and PTH, and histologies. Methylene blue was administered intravenous ly (5 mg/kg diluted in 500 cc of 5% glucose) over a period of time of one hour starting two hours prior to surgery. All 175 procedures were performed by two surgeons and duration of surgery was recorded from th e anesthesiologist's notes. There were 149 adenomas (85%), 24 hyperpla sias (14%), a combination of both in two, and unspecified in two other s. Except for a case of acute lower back pain synchronous to the injec tion of the dye (which was immediately stopped), MB was well tolerated . Mean duration for the 55 interventions performed without MB was 68 m inutes (35 to 140, median 60), compared to 49 minutes for the 120 proc edures carried out after MB had been given (20 to 155, median 45). Dif ferences in operative times were highly significant (p < 10(-6)) and r epresented a gain of time of 27%. Surgery for primary hyperparathyroid ism was significantly shorter when it was preceded by the administrati on of MB, a dye which facilitates the identification of pathologic par athyroid gland(s).