Alison May Berner BA, MBBS, Presenter: Nothing to Disclose

Ewa Nowosinska MBBS, MRCP, Abstract Co-Author: Nothing to Disclose

Athar Haroon MBBS, Abstract Co-Author: Nothing to Disclose

Mo Luqman, Abstract Co-Author: Nothing to Disclose

Margaret W. Newell PhD, Abstract Co-Author: Nothing to Disclose

Hikmat Jan MD, MBChB, Abstract Co-Author: Nothing to Disclose

To evaluate the sensitivity and specificity of SMADT (sequential multiphase and dual tracer) technique utilising 99mTcO4 and Dynamic 99mTc MIBI with SPECT/CT for detection and localisation of hyper-functioning parathyroid tissue and to compare with ultrasound (US).

64 patients (16 male, 48 female, mean age 55 years) with hyperparathyroidism were scanned over 4 years. For SMADT technique, 80 MBq 99mTcO4 was injected with dynamic thyroid image acquisition started at 20 minutes, 900 MBq 99mTc MIBI injection at 30 minutes and dynamic imaging continued until 50 minutes. SPECT was acquired at 60 minutes with further SPECT/CT of the neck at 3 hours. Subsequent subtraction and statistical difference analyses were performed following processing of dynamic data. Neck US was carried out within 3 months. Findings for each parathyroid gland and the thyroid were classified as positive or negative. Patients underwent surgical resection of parathyroid tissue according to imaging results. Histology for each sample was classified as normal, indeterminate, hyperplasia, adenoma or carcinoma. SMADT findings were correlated with histology.  

86 histological samples were resected (18 normal, 6 indeterminate, 9 hyperplasia, 50 adenoma, 3 carcinoma). The sensitivity of both SMADT and neck US for detecting parathyroid hyperplasia, adenoma, carcinoma or indeterminate lesions was 82.3% (95% CI = 70.1-90.4). Sensitivity for localisation to individual glands for SMADT was 70.6% (95% CI = 58.1-80.7) and for neck US was 60.3% (95% CI = 47.7-71.8). Specificity for localisation was 94.4% (95% CI = 70.6-99.7) for SMADT and 72.2% (95% CI = 46.4-89.2) for neck US. SMADT imaging detected two intrathyroidal lesions not seen on neck US.  

SMADT and neck US are equally sensitive for detection of hyper-functioning parathyroid tissue in hyperparathyroid patients. The use of sequential multiphase and dual tracer imaging better facilitates lesion localisation for varying parathyroid pathologies.

Sequential multiphase and dual tracer technique complements the role of previously available imaging modalities for detection and localisation of hyper-functioning parathyroid tissue prior to surgery.

Berner, A, Nowosinska, E, Haroon, A, Luqman, M, Newell, M, Jan, H, “Sequential Multiphase and Dual Tracer” (SMADT) Imaging of the Neck for Detection and Localisation of Parathyroid Disease and Comparison with Ultrasound.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14001695.html