Improved preoperative planning for directed parathyroidectomy with 4-dimensional computed tomography

100

BACKGROUND AND PURPOSE: 4D-CT is a novel method of multiphase CT imaging. When used to localize parathyroid adenomas and hyperplasia, this technique may allow for more robust diagnostic accuracy than traditional sonography and nuclear scintigraphy techniques. The purpose of our study is to assess the accuracy of 4D-CT for localizing pathologically proved parathyroid adenomas and hyperplasia found during surgery.

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Diagnostic Accuracy of 4D-CT for Parathyroid Adenomas and Hyperplasia

Chazen

Gupta²,

Dunning³

et al. 2011

100

“…Therefore investigators have tried to identify acquisition schemes by using a combination of unenhanced and multiple postcontrast phases including 2 [25][26][27] with the time interval ranging from 30 to 90 seconds, each with strengths and limitations.…”

Section: Discussionmentioning

confidence: 99%

Dynamic 4D MRI for Characterization of Parathyroid Adenomas: Multiparametric Analysis

Nael

Hur

Bauer

et al. 2015

“…5 The "fourth" dimension of 4D-CT is the perfusion information derived from noncontrast, arterial, and venous phase imaging. Since this paper was published, different institutions have produced modified protocols.…”

mentioning

confidence: 99%

Parathyroid Lesions: Characterization with Dual-Phase Arterial and Venous Enhanced CT of the Neck

Gafton

Glastonbury

Eastwood

et al. 2012

SUMMARY:This clinical report describes the enhancement characteristics of hypersecreting parathyroid lesions on dual-phase neck CT. We retrospectively analyzed the enhancement characteristics of 5 pathologically confirmed PTH-secreting lesions on dual-phase CT examinations. Attenuation values were measured for PTH-secreting lesions, vascular structures (CCA and IJV), and soft tissue structures (thyroid gland, jugulodigastric lymph node, and submandibular gland). From the attenuation values, "relative enhancement washout percentage" and "tissue-vascular ratio" were calculated and compared. All lesions decreased in attenuation from arterial to venous phase, while the mean attenuation values of other soft tissue structures increased. A high relative enhancement washout percentage was correlated with parathyroid lesions (P Ͻ .006). The tissue-CCA ratio and tissue-IJV ratio for PTHsecreting lesions in the arterial phase were statistically significantly higher compared with soft tissue structures (P Ͻ .05). If these results are validated in future larger studies, noncontrast and delayed venous phases of 4D-CT could be eliminated to markedly reduce radiation exposure.ABBREVIATIONS: CCA ϭ common carotid artery; HU ϭ Hounsfield units; IJV ϭ internal jugular vein; PTH ϭ parathyroid hormone; ROC ϭ receiver operating characteristic curve M ost cases of primary hyperparathyroidism are due to benign parathyroid adenomas and parathyroid hyperplasia. These lesions are sometimes difficult to identify at surgery and on imaging due to variations in number and location of abnormal parathyroid glands, with multiglandular hyperplasia and multiglandular adenomas occurring in up to 14% of cases.1,2 Ectopic parathyroid adenomas and ectopic parathyroid hyperplasia account for 20 -25% of cases.3,4 Initial work-up in a patient with primary hyperparathyroidism usually consists of sonography or technetium (Tc)99m sestamibi scintigraphy with or without SPECT imaging. When these tests are negative, second-tier imaging investigations, such as 4D-CT and MR imaging of the neck, can be helpful in preoperative planning.The original description of 4D-CT includes image sets in 3 planes (axial, coronal, and sagittal).5 The "fourth" dimension of 4D-CT is the perfusion information derived from noncontrast, arterial, and venous phase imaging. Since this paper was published, different institutions have produced modified protocols. Some have interpreted "4D" as a 4-phase neck CT with precontrast and 3 postcontrast phases of neck imaging. 6-9Others image with precontrast and single postcontrast neck phases, 10 or postcontrast arterial and venous phases only. 11Because of these multiple phases of imaging, 4D-CT has been criticized for its high radiation dose. To reduce radiation dose, but still obtain perfusion information that might allow detection of parathyroid lesions, we have modified the protocol at our institution to dual-phase scanning with only arterial and venous phase imaging. The aim of this clinical report is to describe the enhancement characte...