Sakeena J Payne1, Joanne E Smucker1, Michael A Bruno2, Louis S Winner2, Brian D Saunders3, David Goldenberg4. 1. Division of Otolaryngology Head and Neck Surgery, The Pennsylvania State University, College of Medicine, Hershey, PA, USA. 2. Department of Radiology, The Pennsylvania State University, College of Medicine, Hershey, PA, USA. 3. Division of General Surgery Subspecialties and Surgical Oncology, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, PA, USA. 4. Division of Otolaryngology Head and Neck Surgery, The Pennsylvania State University, College of Medicine, Hershey, PA, USA. Electronic address: dgoldenberg@hmc.psu.edu.
Abstract
PURPOSE: Patients with primary hyperparathyroidism routinely undergo preoperative imaging to localize the abnormal gland to facilitate a guided parathyroidectomy. These techniques include neck ultrasound (US), dual phase planar technetium-99m ((99m)TC) sestamibi (MIBI) scans, single photon emission computed tomography (SPECT), combined SPECT/CT, and four dimensional CT scans (4D CT). Despite appropriate preoperative imaging, non-localization of abnormal glands does occur. This study aims to determine whether non-localization is the result of radiologic interpretive error or a representation of a subset of truly non-localizing parathyroid adenomas. MATERIALS AND METHODS: A retrospective study was performed; two senior radiologists reinterpreted the preoperative imaging (US and MIBI scans) of 30 patients with initially non-localizing studies. All patients underwent parathyroidectomy for primary hyperparathyroidism at a tertiary referral center. Both radiologists were blinded to the scores of his colleague. The results were compared for inter-reader reliability using Cohen's kappa test. RESULTS: Twenty-nine of thirty nuclear studies were found to be negative on reinterpretation. The readers agreed in 86.67% of their observations, with a kappa (κ) value of 0.706 (SE=±0.131, 95% confidence interval for κ =0.449-0.962). One of eighteen ultrasounds had positive localizations on reexamination, however, the inter-observer agreement was only 55.6%, with a kappa value of 0.351 (SE=±0.139, and 95% confidence interval for κ =0.080-0.623). Overall, no statistically significant difference in preoperative and retrospective interpretation was found. CONCLUSION: This study identifies a subset of parathyroid adenomas that do not localize on preoperative imaging despite sound radiographic evaluation.
PURPOSE:Patients with primary hyperparathyroidism routinely undergo preoperative imaging to localize the abnormal gland to facilitate a guided parathyroidectomy. These techniques include neck ultrasound (US), dual phase planar technetium-99m ((99m)TC) sestamibi (MIBI) scans, single photon emission computed tomography (SPECT), combined SPECT/CT, and four dimensional CT scans (4D CT). Despite appropriate preoperative imaging, non-localization of abnormal glands does occur. This study aims to determine whether non-localization is the result of radiologic interpretive error or a representation of a subset of truly non-localizing parathyroid adenomas. MATERIALS AND METHODS: A retrospective study was performed; two senior radiologists reinterpreted the preoperative imaging (US and MIBI scans) of 30 patients with initially non-localizing studies. All patients underwent parathyroidectomy for primary hyperparathyroidism at a tertiary referral center. Both radiologists were blinded to the scores of his colleague. The results were compared for inter-reader reliability using Cohen's kappa test. RESULTS: Twenty-nine of thirty nuclear studies were found to be negative on reinterpretation. The readers agreed in 86.67% of their observations, with a kappa (κ) value of 0.706 (SE=±0.131, 95% confidence interval for κ =0.449-0.962). One of eighteen ultrasounds had positive localizations on reexamination, however, the inter-observer agreement was only 55.6%, with a kappa value of 0.351 (SE=±0.139, and 95% confidence interval for κ =0.080-0.623). Overall, no statistically significant difference in preoperative and retrospective interpretation was found. CONCLUSION: This study identifies a subset of parathyroid adenomas that do not localize on preoperative imaging despite sound radiographic evaluation.