A Prospective Comparative Study of Parathyroid Dual-Phase Scintigraphy, Dual-Isotope Subtraction Scintigraphy, 4D-CT, and Ultrasonography in Primary Hyperparathyroidism

Activity: Talk or presentationLecture and oral contribution


Purpose: Preoperative localization of the diseased parathyroid gland
(s) in primary hyperparathyroidism allows for minimally invasive surgery.
This study was designed to establish the optimal first-line preoperative im-
aging modality.
Patients and Methods: Ninety-one patients were studied consecutively in a
prospective head-to-head comparison of dual isotope (99mTc-MIBI vs 123I)
subtraction parathyroid scintigraphy (PS), dual-phase PS, 4-dimensional
(4D) CT, and ultrasonography (US). Surgery, histological confirmation,
and postoperative normalization of Ca++ and parathyroid hormone were the
reference standard.
Results: Ninety-seven hyperfunctioning parathyroid glands (HPGs) were
identified by the reference standard. Sensitivity and specificity for subtrac-
tion PS, dual-phase PS, 4D-CT, and US were 93%, 65%, 58%, and 57%
as well as 99%, 99.6%, 86%, and 95%, respectively. Interrater agreement
was excellent for subtraction PS (! = 0.96) while only fair for 4D-CT (! =
0.34). Pinhole imaging and subtraction of delayed images (the latter espe-
cially in case of a nodular thyroid gland) increased the sensitivity of subtrac-
tion PS. SPECT/low-dose CT did not increase sensitivity but aided in the
exact localization of the HPGs. Of 7 negative subtraction PS studies,
4D-CT and US were able to locate 3 and 1 additional HPGs, respectively.
Conclusions: Dual isotope pinhole subtraction PS has higher diagnostic ac-
curacy compared with dual-phase PS, 4D-CT, and US as a first-line imaging
study in primary hyperparathyroidism. In case of a negative scintigraphy or
suspicion of multiglandular disease, 4D-CTand/or US is recommended as a
second-line modality. However, diagnostic algorithms should be adapted in
accordance with local availability and expertise.
Period11 Oct 2015
Event titleEANM 2015
Event typeConference
LocationHamborg, GermanyShow on map