What steps should be considered in the patient who has had a negative cervical exploration for primary hyperparathyroidism?

The key to cure of the patient with persistent primary hyperparathyroidism is a clear understanding of the investigations, operative procedure and pathology related to the initial procedure. Reinvestigation and subsequent surgery should be performed in a specialist unit. A logical pathway of increasingly sophisticated localization studies (MIBI, ultrasound, CT/MRI, selective venous catheterization for PTH) will usually guide the surgeon to the missing parathyroid gland/s. Improved preoperative localization can facilitate the use of a minimally invasive small incision approach. The surgeon must have a detailed knowledge of the nuances of parathyroid embryology and a meticulous surgical technique, not only to identify and safely remove the retained gland/s but also do so without causing unnecessary morbidity. Results of re-operation (84-98% cure) from centres of excellence are highly commendable, yet the use of 'new' technology (that includes intra-operative PTH) has not translated into improved outcomes in all cases. Some parathyroid glands are extremely difficult to find! Re-operative parathyroid surgery is a challenge, sometimes easy, and on other occasions extremely difficult.