A RETROSPECTIVE COHORT STUDY COMPARING DUAL-ISOTOPE SUBTRACTION SPECT/CT WITH DUAL-PHASE SPECT/CT FOR PREOPERATIVE LOCALIZATION BEFORE PARATHYROIDECTOMY

AUTHORS:
S. O'Connor (Cork, Ireland) , L. Kent (Cork, Ireland) , R.Y. Teo (Cork, Ireland) , H. Al Harthi (Cork, Ireland) , Y. Al Mukhaizeem (Cork, Ireland) , S. Paul (Cork, Ireland) , S. Rupani (Cork, Ireland) , A. Mehmood (Cork, Ireland) , B. O'Flynn (Cork, Ireland) , P. Redmond (Cork, Ireland) , M. Moore (Cork, Ireland)
Background:
The gold standard treatment for primary hyperparathyroidism is parathyroidectomy. Preoperative localization of parathyroid adenomas enables minimally invasive surgery. The aim of this study was to directly compare the diagnostic accuracy of dual-isotope subtraction single-photon emission computed tomography/computerized tomography /SPECT/CT with dual phase SPECT/CT for localization of abnormal parathyroid glands in patients with primary hyperparathyroidism. While a number of studies have reviewed the accuracy of these preoperative modalities independently, few have directlycompared their sensitivity and specificity.
Methods:
Methods: We conducted a single centre retrospective cohort study including patients who underwent dual isotope SPECT/CT or dual phase SPECT/CT and parathyroidectomy for primary hyperparathyroidism in Cork University Hospital from July 2022 to September 2023. We analyzed the reports of their radiological scans and assessed concordance with final pathological reports.
Results:
Results: A total of 72 patients were included in this study. 36 underwent dual-isotope subtraction SPECT/CT and 36 underwent dual phase SPECT/CT. Sensitivity of dual isotope scanning was 76% while sensitivity of dual phase imaging was 53%. Specificity of both modalities was 100%. 20 of 36 lateralized correctly on dual-isotope imaging while 14 of 36 lateralized correctly on dual phase imaging. 13 of 27 localized correctly on dual isotope while 6 of 27 localized correctly on dual phase imaging.
Conclusions:
Dual isotope imaging was more specific than dual phase imaging for parathyroid disease. Dual isotope imaging was also a superior modality for lateralizing and localizing parathyroid disease. Further studies should include larger cohorts to confirm these findings.