Spectral CT/Dual-Energy CT

Dual‐energy CT iodine quantification for characterizing focal thyroid lesions

“…In this study, we used a recently implemented DECT scanner, which only a few studies used . This scanner achieves spectral separation using a different method from the previous fast‐kVp switching scanner in which the X‐ray tube rapidly modulates tube voltage . In contrast, our DECT scanner built with 2 scintillating layers has a single X‐ray source that operates at a fixed tube potential, typically 120 or 140 kVp .…”

“…[30][31][32][33][34][35] This scanner achieves spectral separation using a different method from the previous fast-kVp switching scanner in which the X-ray tube rapidly modulates tube voltage. 7,8,10 In contrast, our DECT scanner built with 2 scintillating layers has a single X-ray source that operates at a fixed tube potential, typically 120 or 140 kVp. 7,8,10 Its upper yttrium-based layer mostly absorbs low-energy photons, whereas the lower gadoliniumbased layer mostly absorbs high-energy photons.…”

“…7,8,10 In contrast, our DECT scanner built with 2 scintillating layers has a single X-ray source that operates at a fixed tube potential, typically 120 or 140 kVp. 7,8,10 Its upper yttrium-based layer mostly absorbs low-energy photons, whereas the lower gadoliniumbased layer mostly absorbs high-energy photons. These simultaneously obtained different energy data sets are decomposed in projection space to generate a materialspecific or energy-specific display based on the differences in X-ray attenuation and changes in attenuation at different energy levels, in addition to routine diagnostic images by directly combing data from the top and bottom layers.…”

“…1,6 The recent technical advance of dual-energy CT (DECT) has provided the material-specific imaging, also known as material decomposition, which can separate several numbers of substances, such as water, iodine, calcium, uric acid, and fat. [7][8][9][10] Especially, quantitative information for iodine distribution, among the DECT-based material decomposition techniques, has been considered a promising tool for lesion characterization to distinguish not only malignancy from benignity but also hyperdense cystic lesions or hematomas from enhancing lesions. 7,8,[10][11][12][13][14][15][16][17][18] In the head and neck region, several studies showed iodine concentration (IC) could be useful in CT imaging of cervical lymph nodes or patients with underlying neck malignancy.…”

“…[7][8][9][10] Especially, quantitative information for iodine distribution, among the DECT-based material decomposition techniques, has been considered a promising tool for lesion characterization to distinguish not only malignancy from benignity but also hyperdense cystic lesions or hematomas from enhancing lesions. 7,8,[10][11][12][13][14][15][16][17][18] In the head and neck region, several studies showed iodine concentration (IC) could be useful in CT imaging of cervical lymph nodes or patients with underlying neck malignancy. [19][20][21][22] Until now, a few studies have evaluated IC of thyroid nodules using the DECT data sets to find the malignancy or intranodular hemorrhage; however, they decided the individual CT images for quantification without the detailed topographic knowledge based on ultrasound, which is widely considered as reference imaging modality to assess thyroid nodule.…”