Minimally Invasive Radio-guided Parathyroidectomy (MIRP)
If a single abnormal gland is identified on sestamibi scan, this patient becomes a candidate for minimally invasive radio-guided parathyroidectomy guided (MIRP) by a gamma probe. Once the abnormally functioning gland has been removed, the incision is closed without any further exploration. If an abnormally functioning gland is not identified using the minimal invasive approach, the procedure is converted to a standard neck exploration.
Preoperative localization using the technetium sestamibi radioisotope scan is performed as part of the diagnostic work up prior to the day of surgery. This allows clear identification of suitable candidates for the minimal invasive approach and those who would need a standard bilateral neck exploration.
Prior to MIRP on the day of surgery, the patient receives an additional dose of technetium sestamibi.
In the operating room, the gamma probe is used to locate the abnormal gland because of the radioactivity given off by the sestamibi. Exploration is carried out through a smaller incision than the standard neck exploration, limited to the site in the neck with the highest radioactivity counts. Precisely guided by the gamma probe, the abnormal gland can be identified with minimal dissection of the deeper tissues and then removed. The incision is closed without drains. Most patients are discharged on the same day as surgery or by the following morning. Minimal postoperative care is required. The incision is cleaned with a daily shower and antibiotic ointment applied. Calcium levels are obtained in the recovery room and the next day. Outpatients are contacted the next day by a health care professional to determine their status.
Since defining a clearly positive sestamibi scan as selection criteria for minimally invasive radioguided parathyroidectomy, we have not found it necessary to convert to standard neck exploration on a patient selected for a minimally invasive approach.
Not all patients with primary hyperparathyroidism are candidates for this minimally invasive approach. If the sestamibi scan does not identify a single abnormal gland, standard bilateral neck exploration is recommended. The measurement of PTH Intra operatively determines the extert of surgical exploration. PTH assay is obtained prior to neck exploration. In the operating room, standard bilateral neck exploration is carried out with the identification of abnormal gland or glands. The abnormal gland or glands are removed. Intraoperative parathyroid hormone measurements (PTH assay) are performed before and after the abnormal appearing glands have been removed. With appropriate fall in the PTH level, the incision is closed. A few of these patients are discharged on the same day as surgery. Most will leave the hospital within 23 hours.
