Use of dual-layer spectral detector computed tomography in the diagnosis of pancreatic neuroendocrine neoplasms

To explore the optimal energy level of dual-layer spectral detector computed tomography (DLCT) images of pancreatic neuroendocrine neoplasms (pNENs) and investigate the value in their detection.This retrospective analysis included 134 pNEN patients with 136 lesions; they underwent contrast-enhanced DLCT scanning with histopathological confirmation of pNENs. Virtual monoenergetic images (VMI) of 40-100 keV, iodine concentration map (IC map), Z-effective atomic number map (Zeff map), and conventional images were analysed. The optimal energy level was obtained by comparing the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). The lesion detection rates of DLCT and conventional images were compared. Subjective image analysis was performed by two readers who assessed the image quality and lesion conspicuity on a 5-point scale.The SNR of VMIs from 40 to 80 keV (arterial phase, P 0.001; venous phase, P 0.05) and CNR from 40 to 60 keV (arterial and venous phases, each P 0.05) were higher than that of conventional images; VMIThe VMI