RT Journal Article
SR Electronic
T1 Parathyroid Imaging: The Importance of Pinhole Collimation with Both Single- and Dual-Tracer Acquisition
JF Journal of Nuclear Medicine Technology
JO J. Nucl. Med. Technol.
FD Society of Nuclear Medicine
SP 99
OP 104
DO 10.2967/jnmt.112.118208
VO 41
IS 2
A1 Klingensmith, William C.
A1 Koo, Phillip J.
A1 Summerlin, Adam
A1 Fehrenbach, Bradley W.
A1 Karki, Ramesh
A1 Shulman, Benjamin C.
A1 Raeburn, Christopher D.
A1 McIntyre, Robert C.
YR 2013
UL http://tech.snmjournals.org/content/41/2/99.abstract
AB Our objective was to rigorously compare pinhole and parallel-hole collimation in an intrapatient, intrastudy design in 2 parathyroid imaging protocols: the first was dual-phase 99mTc-sestamibi imaging, and the second was dual-phase 99mTc-sestamibi plus dual-tracer (99mTc-sestamibi and 123I) simultaneous-acquisition subtraction imaging. Methods: Thirty-three patients with 37 surgically proven nonectopic parathyroid adenomas were evaluated. Anterior pinhole and parallel-hole images of the neck were available for 99mTc-sestamibi at 15 min and 3 h, and for simultaneously acquired 99mTc-sestamibi and 123I subtraction at 15 min, all from a single study. The images were modified so that all had a square border and so that the thyroid filled approximately three quarters of the image. The images were evaluated by 2 experienced nuclear medicine physicians who did not know the surgical results or whether the images were acquired with pinhole or parallel-hole collimation. The observers indicated the location of any identified adenoma and graded the certainty of diagnosis on a 3-point scale. Results: The localization success rate for the 2 observers combined for the single-tracer dual-phase images was 66.2% with pinhole collimation and 43.2% with parallel-hole collimation (P < 0.0001). The localization success rate with the addition of the dual-tracer simultaneous-acquisition subtraction image was 83.8% with pinhole collimation and 62.2% with parallel-hole collimation (P = 0.0018). In addition, the degree of certainty of localization was greater with pinhole collimation with both imaging protocols (P < 0.001 in both cases). Conclusion: In the anterior projection, pinhole collimation is superior to parallel-hole collimation for parathyroid imaging with either dual-phase 99mTc-sestamibi or dual-phase 99mTc-sestamibi plus dual-tracer (99mTc-sestamibi and 123I) simultaneous-acquisition subtraction.