title: Parathyroid Imaging with Simultaneous Acquisition of 99mTc-Sestamibi and 123I: The Relative Merits of Pinhole Collimation and SPECT/CT.
abstract: The objective of this study was to determine the relative utility of 3 state-of-the-art parathyroid imaging protocols: single-time-point simultaneous acquisition of (99m)Tc-sestamibi and (123)I images with pinhole collimation in the anterior and bilateral anterior oblique projections, single-time-point simultaneous acquisition of (99m)Tc-sestamibi and (123)I images with SPECT/CT, and the combination of the first and second protocols.
  
  
  METHODS
  Fifty-nine patients with surgical proof of parathyroid adenomas were evaluated retrospectively. All 3 protocols included perfectly coregistered subtraction images created by subtracting the (123)I images from the (99m)Tc-sestamibi images, plus an anterior parallel-hole collimator image of the neck and upper chest. The pinhole protocol was performed first, followed by the SPECT/CT protocol. Three image sets were derived from each study in each patient according to the above protocols. Two experienced observers recorded the size, location, and degree of certainty of any identified lesion.
  
  
  RESULTS
  The 59 patients had 61 adenomas. For the 2 observers combined, the localization success rate was 88% for the pinhole protocol, 69% for the SPECT/CT protocol, and 81% for the combined protocol. The pinhole protocol detected more adenomas than the SPECT/CT protocol and missed fewer adenomas than either the SPECT/CT protocol or the combined pinhole and SPECT/CT protocol (P < 0.01). The 2 protocols that included SPECT/CT provided superior anatomic information relative to the location and size of the parathyroid adenomas.
  
  
  CONCLUSIONS
  The pinhole protocol localized significantly more adenomas than the SPECT/CT protocol. However, the protocols that included SPECT/CT provided more anatomic information than pinhole imaging alone.
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, University of Colorado School of Medicine, Aurora, Colorado paraag.bhatt@ucdenver.edu.
authors.forename: Paraag R
authors.initials: PR
authors.lastname: Bhatt
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: William C
authors.initials: WC
authors.lastname: Klingensmith
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Brian M
authors.initials: BM
authors.lastname: Bagrosky
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Jacob C
authors.initials: JC
authors.lastname: Walter
authors.affiliation: Department of Biostatistics and Informatics, Colorado School of Public Health, Aurora, Colorado; and.
authors.forename: Kim K
authors.initials: KK
authors.lastname: McFann
authors.affiliation: Division of GI, Tumor and Endocrine Surgery, Department of Surgery, University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Robert C
authors.initials: RC
authors.lastname: McIntyre
authors.affiliation: Division of GI, Tumor and Endocrine Surgery, Department of Surgery, University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Raeburn
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Koo
mesh_terms: D000328:Adult; D000368:Aged; D003413:Cricoid Cartilage / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D010280:Parathyroid Glands / Q000000981:diagnostic imaging*; D017256:Technetium Tc 99m Sestamibi; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
chemical_list: D007457:Iodine Radioisotopes; D017256:Technetium Tc 99m Sestamibi
keywords: I-123; SPECT/CT; Tc-99m-sestamibi; camera-based high energy imaging; endocrine; parathyroid imaging; pinhole collimation