Minimally invasive parathyroid surgery (MIP)
It is performed targeting on one specific parathyroid glad that is known to be enlarged on localization studies. The surgery is performed under general anaesthetic, but it can be done under local anaesthetic. This concept is based on principle that 85% of patients will have unilateral disease. There are several types and not all are performed in New Zealand.
Unilateral neck exploration – Exploring/identifying both parathyroid glands on the side that has been shown on localization studies. The enlarged gland is removed. If second gland is found to be normal, then there is no need to perform bilateral (both sides) exploration. If both glands are bound to be enlarged or normal, then bilateral gland exploration is performed.
Open minimally invasive parathyroidectomy - performed through smaller 2-4cm incision. Only 1 gland is explored, the one that has been found to be enlarged on the localization studies. This procedure may be day procedure and can be associated with overnight stay. It has less complications then the bilateral or 4 gland exploration (1% vs 3%) and is much shorter procedure. This is the procedure I tend to perform. I also usually perform unilateral cervical block (using local anaesthetic agent) to minimize post-operative pain.
Minimally invasive radionucleotide guided parathyroidectomy – not performed in New Zealand or most places in the world. Radioactive nucleotide is injected prior to surgery and used to target the enlarged gland, a bit similar to sentinel node biopsy (in the breast section of my website).
Endoscopic parathyroidectomy – is not performed in New Zealand or most places in the world. Many approaches have been used. More expensive and longer surgery, without any obvious improvement to open MIP apart from less pain relief use.
Bilateral parathyroidectomy or 4-gland exploration
It is performed when the enlarged parathyroid gland was not identified on the localization studies or patient has secondary hyperparathyroidism. This surgery is performed under general anaesthesia with transverse (collar like) incision in the middle of the anterior neck. I usually also perform bilateral cervical block to help with post-operative pain relief. All 4 parathyroid glands are identified and the enlarged gland removed. In cases of secondary hyperparathyroidism, at least 3-3.5 glands are removed. At times the surgeon may not be able to identify all 4 glands due to unusual position of the glands.
The surgeon will then use their experience and knowledge of the positions that the parathyroid glands may be found and explore them. The success of the surgery depends mostly on the experience of the surgeon performing the procedure. Patients should always look for experienced surgeon to perform this procedure to minimize the risk of complications and failure to find the gland causing the hyperparathyroidism. The risk of failure is still up to 8% even in experienced hands and increases in the cases of re-operative surgery.