The value and role of low dose methylene blue in the surgical management of hyperparathyroidism.

INTRODUCTION

Methylene blue (MB) has been used in the identification of abnormal parathyroid glands in surgery for hyperparathyroidism. Its efficacy and safety profile have been questioned recently and this study sought to demonstrate such aspects in a unit where its use is routine.

METHODS

Prospective data collected over six years in a single surgeon's practice were interrogated to identify factors affecting MB staining, side effects suffered and unusual cases where the dye was invaluable in locating the diseased gland.

RESULTS

A total of 98 patients underwent MB infusion. Of these, 77 cases (78.6%) stained positively with MB and 21 (21.4%) did not. Six patients suffered side effects but there were no cases of neurotoxicity. No positive predictive factors of dye uptake were found. MB was particularly useful in cases of intrathyroidal and ectopic glands as well as improving efficiency in both targeted and open parathyroidectomy.

CONCLUSIONS

This series shows that when used correctly, MB is efficacious in locating diseased parathyroid glands, with similar sensitivity rates to preoperative ultrasonography and radionucleotide imaging. Adverse effects were much lower than published previously, which may be attributed to the low dose of MB used (3.5 mg/kg).