Effect of minimally invasive radioguided parathyroidectomy on efficacy, length of stay, and costs in the management of primary hyperparathyroidism

Abstract

Objective: To compare the first 20 patients who underwent minimally invasive radioguided parathyroidectomies (MIRPs) performed at the authors' institution with 20 similar patients who underwent a more conventional surgical approach for primary hyperparathyroidism.

Summary background data: The technique of parathyroidectomy has traditionally involved a bilateral exploration of the neck with the intent of visualizing four parathyroid glands and resecting enlarged parathyroid glands. Parathyroid scanning using radioisotopes has evolved and now can localize adenomas in 80% to 90% of patients. MIRP combines parathyroid scanning with a hand-held intraoperative detector that guides the surgeon to the adenoma.

Methods: Forty patients with documented primary hyperparathyroidism who underwent surgery by a single surgeon between January 1998 and May 1999 were included in this study. Twenty of these patients underwent MIRP. The technique involved injecting 20 mCi technetium-99m sestamibi 2 hours before surgery and performing a parathyroid scan. If the scan was considered positive for a single adenoma, patients were taken to the operating room and given the choice of either general anesthesia or intravenous sedation with local anesthesia. Using an incision of 4 cm or less, the dissection down to the adenoma was guided by the Navigator miniature hand-held probe. An additional 20 patients who underwent more conventional bilateral or unilateral neck exploration were chosen to match the MIRP patient population. Both groups included four patients undergoing repeat surgery for persistent or recurrent primary hyperparathyroidism and one patient with multiple endocrine neoplasia type 1 syndrome. Patient demographics, preoperative calcium and parathyroid hormone levels, operative time, total time in the operating room, time in the recovery room, complications, hospital charges for the operating room, and total hospital charges were analyzed.

Results: There were no differences in patient demographics, presenting symptoms, or preoperative calcium level between patients undergoing the standard procedure versus MIRP. Operative time, total time in the operating room, operative charges, and total hospital charges were significantly reduced in the MIRP group. All 40 patients were cured of primary hyperparathyroidism. There were no recurrent laryngeal nerve injures in either group. The mean length of stay in the standard group was 1. 35 days; in the MIRP group, 65% of patients were discharged within 5 hours after surgery.

Conclusions: The MIRP technique resulted in excellent cure rates for primary hyperparathyroidism while simultaneously decreasing operative time and hospital stays. These resulted in significant cost reductions without compromising patient safety. The technique may significantly change the management of primary hyperparathyroidism.

Figure 1. Initial (A) and delayed (B) parathyroid scans demonstrating a large right parathyroid adenoma. The use of anterior, left anterior oblique, and right anterior oblique views helped to demonstrate that the adenoma lay quite posterior and medial relative to the right thyroid lobe.

Figure 2. Initial (A) and delayed (B) parathyroid scans demonstrating a small right-sided parathyroid adenoma. This patient was referred after having undergone two previous unsuccessful neck explorations. The use of anterior, left anterior oblique, and right anterior oblique views helped to demonstrate that the adenoma was either close to the right thyroid lobe or was an intrathyroidal adenoma. The adenoma was, in fact, completely intrathyroidal.

Figure 3. A minimally invasive radioguided parathyroidectomy (MIRP). Through a small incision, the hand-held gamma probe helps to determine the line of dissection down to the right inferior parathyroid adenoma.

Figure 4. Algorithm followed by patients scheduled to undergo minimally invasive radioguided parathyroidectomy (MIRP).

Figure 5. Sestamibi parathyroid scan from a patient with MEN1 syndrome. Twenty years ago, only the two inferior parathyroid glands were identified and removed. The scan identified the location of the two missed superior parathyroid glands.