Parathyroid Disease
Parathyroid disease is due to abnormal function of one of four parathyroid glands in your neck. These are located on each side of your thyroid gland, although sometimes they can be in abnormal locations when they enlarge. Most patients (95%) with parathyroid disease have one of four glands enlarged (a parathyroid adenoma). The other 5% have all four glands enlarged (parathyroid hyperplasia). Rarely there may be a so-called double adenoma. For those patients with one gland enlarged, surgery has evolved into Minimally Invasive Parathyroid Surgery. Patients with hyperplasia will usually require the traditional operation exploring both sides of the neck. They may require the removal of more then one gland.
Traditional and Minimally Invasive Parathyroid Surgery and
Intraoperative PTH
Traditional parathyroid surgery explores both sides of the neck to identify normal or abnormal parathyroid glands. The average patient has 4 glands, less the 1% may have 5 or more. Minimally invasive parathyroid surgery relies on pre-operative tests to localize the abnormal gland to one side. This permits a focused operation, significantly lowers the complication rate, operative time and post-operative course.
Minimally Invasive Parathyroid Surgery relies on either a pre-operative study using radioactive isotopes (Sestamibi) or ultrasound. Sometimes both studies are done, and at times ultrasound is combined with CT scanning for further accuracy. Some medical centers report accuracy rates of almost 95% in localizing the side of an abnormal parathyroid gland before surgery.
If the gland is found with a radioisotope before surgery, a device can be used during the surgery to help find the abnormal gland. (Gamma-probe, Navigator, etc.) This is called Minimally Invasive Radio-guided Parathyroid Surgery.
PTH stands for parathyroid hormone. It is produced by the parathyroid gland and is the hormone or chemical in your blood that controls calcium levels in your body. It increases with parathyroid disease. PTH can be measured in the operating room to make sure it is returning to normal levels because of the parathyroid surgery being performed. It is known in the medical literature as Intraoperative PTH or IPTH.
Minimally Invasive Radio-guided Parathyroid Surgery (MIRP)
MIRP is not new. It has been performed throughout the United States for over 5 years. The technique utilizes the fact that most single enlarged parathyroid glands emit radioactivity when certain radioactive isotopes are injected into the human body. These isotopes concentrate in the parathyroid gland. The one almost all parathyroid surgeons use is called Sestamibi. It is rapidly taken up and rapidly excreted. The radioactive emission is very low and has no effect on other parts of the body in the diagnostic doses that are used. This technique is reserved for patients who have had a positive Sestamibi study preoperatively.
Patients are usually injected 1 to 1 1/2 hours prior to surgery They are then brought to the operating room. The operation can be performed under either general or local anesthesia. This depends on the surgeons preference and the location of the abnormal gland. After anesthesia is obtained a small horizontal incision is made in a natural skin crease in the lower neck. The deeper tissue on the side of the abnormal gland is explored and the area where the gland may reside is exposed. A radioactivity reading device, a gamma probe (see picture) is now used to map the surgical site, with higher emissions suggesting the location of the abnormal gland.
The Risks of Parathyroid Surgery
The main risks of parathyroid surgery are:
• Anesthetic risk
• Bleeding after surgery
• Injury to the nerves that work your vocal cords
• Low blood calcium level
• Failure to cure the disease
What to expect after surgery
You will usually wake up in the recovery room You will have some pain in your throat and of your neck. You may have to go to the bathroom. There will be nurses in the recovery room to take care of your every need. They will administer medications and pain medicines and perform any other functions that are required for your post-operative care. You will be able to talk and will be able to start oral intake when you are fully awake. You will be followed closely by the surgical team. Blood will be drawn to follow your blood calcium level. If it is low it will be replaced.
There will be a large bandage around your neck which will be removed before your discharge. Once you are discharged from the recovery room to a step-down or out-take unit you will be able to get out of bed, eat and converse with members of your family.
Most parathyroid surgery patients go home after a 6 hour post-operative stay.
You will usually see your surgeon 4 to 7 days after your surgery for suture removal and wound inspection. Your medications may be adjusted at that time.
