In 2 prospective studies performed at 3.0T, the sensitivity of MRI neck without and with IV contrast ranged between 64% and 98%, and the PPV ranged between 67% and 95% [49,50]. A third prospective study of MRI without and with IV contrast performed at 3.0T reported accurate localization of parathyroid adenomas in 92% (34/37) of patients with single-gland disease and 74% (35/47) of patients with MGD [51]. For MRI without IV contrast, the reported sensitivity was 67% at 1.5T [52]. There is no relevant literature regarding the use of 3.0T MRI without IV contrast in the initial imaging evaluation of PHPT. Sestamibi Dual-Phase Scan Neck Dual-phase Tc-99m sestamibi planar parathyroid scintigraphy is an accepted and traditionally widely utilized method for parathyroid adenoma localization in PHPT. The sensitivity of this method (typically reported as localization to the correct quadrant or to an ectopic location) varies widely in the literature, ranging from 41% to 96% [45,52-63]. A larger retrospective study of 180 patients reported a sensitivity of 79% [58]. A systematic review of 11 studies reported a pooled sensitivity of 76% [17]. Some variability in these results may arise from varied technical parameters of these scans (eg, timing of early and delayed scans, use of pinhole versus parallel collimators, addition of oblique acquisitions, etc). There is no clear consensus regarding the superiority between sestamibi dual-phase and dual-tracer subtraction planar imaging. One recent study of 63 patients showed greater sensitivity with dual-phase sestamibi (79%) over both dual-tracer (sestamibi and pertechnetate) (69%) and a combined dual-tracer/dual-phase technique (65%) [59]. However, other studies report similar or improved sensitivity of dual-tracer methods (either pertechnetate or I-123, plus sestamibi) over dual-phase sestamibi when utilizing a planar technique [45,54,64,65]. There is a growing Parathyroid Adenoma
Parathyroid Adenoma. In 2 prospective studies performed at 3.0T, the sensitivity of MRI neck without and with IV contrast ranged between 64% and 98%, and the PPV ranged between 67% and 95% [49,50]. A third prospective study of MRI without and with IV contrast performed at 3.0T reported accurate localization of parathyroid adenomas in 92% (34/37) of patients with single-gland disease and 74% (35/47) of patients with MGD [51]. For MRI without IV contrast, the reported sensitivity was 67% at 1.5T [52]. There is no relevant literature regarding the use of 3.0T MRI without IV contrast in the initial imaging evaluation of PHPT. Sestamibi Dual-Phase Scan Neck Dual-phase Tc-99m sestamibi planar parathyroid scintigraphy is an accepted and traditionally widely utilized method for parathyroid adenoma localization in PHPT. The sensitivity of this method (typically reported as localization to the correct quadrant or to an ectopic location) varies widely in the literature, ranging from 41% to 96% [45,52-63]. A larger retrospective study of 180 patients reported a sensitivity of 79% [58]. A systematic review of 11 studies reported a pooled sensitivity of 76% [17]. Some variability in these results may arise from varied technical parameters of these scans (eg, timing of early and delayed scans, use of pinhole versus parallel collimators, addition of oblique acquisitions, etc). There is no clear consensus regarding the superiority between sestamibi dual-phase and dual-tracer subtraction planar imaging. One recent study of 63 patients showed greater sensitivity with dual-phase sestamibi (79%) over both dual-tracer (sestamibi and pertechnetate) (69%) and a combined dual-tracer/dual-phase technique (65%) [59]. However, other studies report similar or improved sensitivity of dual-tracer methods (either pertechnetate or I-123, plus sestamibi) over dual-phase sestamibi when utilizing a planar technique [45,54,64,65]. There is a growing Parathyroid Adenoma