PERFORMING MINIMALLY INVASIVE PARATHYROID SURGERY: The New Approach to Treating Hyperparathyroidism

Hyperparathyroidism is a condition causing high blood-calcium levels that afflicts about 100,000 Americans each year. It is caused by the overproduction of parathyroid hormone (PTH) by one or more of the four parathyroid glands located in the neck. This chronic condition may result in kidney stones, osteoporosis, abdominal problems, fatigue, and depression, among other illnesses. It can successfully be treated by removing the abnormal parathyroid gland(s).

Surgery to remove abnormal parathyroid glands is indicated for moderate to severe symptoms of hyperparathyroidism. In cases where the problem is an adenoma (benign tumor), just the one gland will be removed. If all four glands are enlarged (hyperplasia), the surgeon will likely remove most (three and a half) or all of them.

Traditionally, parathyroid surgery has involved a long incision, exploration on both sides of the neck, and general anesthesia. Four parathyroid glands were identified through a bilateral neck exploration, and an enlarged parathyroid gland was excised. The patient experienced cure with marked resolution of his symptoms and signs of hyperparathyroidism. The results in large series with this procedure demonstrate cure rates that exceed 95%, with complication rates in the range of 1% to 2%.

A new technique — known in the medical literature as minimally invasive parathyroidectomy (MIP) — offers a safer and less invasive approach. It can be performed in the ambulatory surgery setting, under local anesthesia, through a small incision with minimal risk to the patient.

Preoperatively, a radioisotope “sestamibi” scan is used to help locate a tumor or abnormal parathyroid gland prior to surgery. The radioactive isotope is absorbed only by the overactive parathyroid gland(s) — not healthy ones and therefore helps determine where the abnormal gland is. During the operation, the surgeon uses the sestamibi scan results and/or ultrasound as a map to pinpoint the location of the abnormal gland. In some cases, a miniature hand-held probe that detects radioactivity, much as a Geiger counter does, is used to confirm the location.

The entire MIP operation can usually be performed through a small (about 1-inch) incision in the neck. It generally takes less than an hour and usually can be performed under local anesthesia, the use of which avoids a general anesthetic and enables the patient to go home a few hours after surgery.

Once the abnormal parathyroid gland has been removed, a blood sample is drawn from the patient and sent for rapid assay of PTH. Stony Brook’s special laboratory services can provide the results within half an hour. A drop in the level of the hormone to normal or near-normal range helps the surgeon be confident that the operation is complete — that is, whether or not another “normal” gland will need to be removed. It is generally not necessary to perform more extensive exploration to find any other parathyroid glands, and this avoidance of further exploration minimizes the risk of surgical complications.

The newly developed minimally invasive approach to parathyroid surgery is well tolerated by patients, and is associated with cure rates that are at least as good as those attained through traditional bilateral neck exploration. Moreover, the complication rate is less than 1%, which is exceedingly low.