Intraoperative freehand SPECT as an alternative imaging technique for use in radioguided parathyroidectomy.

Freehand single photon emission computed tomography (fhSPECT) is a technique that is used to monitor body's radioactivity intraoperatively. Accordingly, in this study, the feasibility of using fhSPECT for intraoperative 3D mapping in radioguided parathyroidectomy has been assessed. Patients, who were diagnosed with primary hyperparathyroidism consecutively, were scanned intraoperatively using fhSPECT to locate parathyroid adenomas before surgical procedure. The fhSPECT images were acquired intraoperatively using a declipseSPECT device (SurgicEye). The fhSPECT protocol could not be completed due to the technical problems in one patient. Parathyroid adenoma was located in the first patient with no lateral deviation. Nevertheless, a deviation of 8 mm was detected in the depth of the parathyroid adenoma, which is the distance of parathyroid adenoma from the skin. A 20 mm lateral deviation and a 10 mm deviation in depth were detected in the second patient. In the third patient, as was the case in the first patient, parathyroid adenoma was located with no lateral deviation. However, there was a 15 mm deviation in the depth of the parathyroid adenoma. A 5 mm lateral deviation was detected in the fourth patient yet with no deviation in the depth of parathyroid adenoma. Finally, neither lateral nor vertical deviation was detected in fifth patient. Based on the findings of this study, it was concluded that the fhSPECT technology can be helpful to a certain degree in locating the parathyroid adenoma. However, further studies are needed to support the findings of this preliminary study.