Objective This study aimed to distinguish between esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) using spectral computed tomography (CT) and to discuss the accuracy according to an optimal threshold of single and combined parameters. Methods In this monoinstitution study, 61 patients, 35 of whom had ESCC and 26 had EAC confirmed by surgery or esophagoscopy, were recruited from August 2016 to March 2017. Enrolled patients underwent dual-phase chest CT enhancement. The spectral CT parameters (NIC, NICD, NICratio, Z eff, Z eff-C, K 40–70 keV, K 80–100 keV, and K 110–140 keV) were measured during arterial phase (AP) and venous phase (VP). Binary logistic regression was used to calculate combined predictive probability. Thresholds of quantitative parameters and diagnostic accuracy were calculated using receiver operating characteristic curve. Results Compared with ESCC, higher NICAP, NICVP, NICD, Z eff AP, Z eff VP, Z eff-C AP, and Z eff-C VP were observed for EAC, whereas NICratio was lower for EAC. Higher K 40–70 keV, K 80–100 keV, and K 110–140 keV were exhibited in EAC than in ESCC. Area under the curve (AUC) of NICAP, K 40–70 keV AP, and Zeff AP were 0.720, 0.730, and 0.706, respectively. The area under the curve of new combined predictive value of NICAP and λ40–0 keV AP was 0.804. The sensitivity and specificity were 77.80% and 80.60%, respectively, when the threshold of new predictive value was 0.60. Conclusion The diagnostic accuracy obtained by using NICAP and K 40–70 keV AP combined is better than that obtained using a single parameter in differentiation between a diagnosis of squamous cell carcinoma and adenocarcinoma.

AIMTo evaluate the T stage of esophageal squamous cell carcinoma (ESCC) using preoperative low-dose esophageal insufflation computed tomography (EICT).METHODSOne hundred and twenty ESCC patients confirmed by surgery or esophagoscopy were divided into three groups. Groups B and C were injected with 300 mgI/kg contrast medium for automatic spectral imaging assist (GSI assist), while group A underwent a conventional 120 kVp computed tomography (CT) scan with a 450 mgI/kg contrast medium injection. EICT was performed in group C. Group A was reconstructed with filtered back projection, and groups B and C were reconstructed with 50% adaptive statistical iterative reconstruction. The contrast-to-noise ratio of lesion-to-mediastinal adipose tissue and the radiation dose were measured. Specific imaging features were observed, and T stage ESCCs were evaluated.RESULTSThe sensitivity and accuracy of the T1/2 stage were higher in group C than in groups A and B (sensitivity: 43.75% vs 31.82% and 33.33%; accuracy: 54.29% vs 46.67% and 52.50%, respectively). With regard to the T3 stage, the sensitivity and specificity in group C were higher than those in groups A and B (sensitivity: 56.25% vs 41.17% and 44.44%; specificity: 73.68% vs 67.86% and 63.64%, respectively). The diagnostic sensitivity, specificity and accuracy of the T4 stage were similar among all groups. There were no significant differences in volume CT dose index [(5.91 ± 2.57) mGy vs (3.24 ± 1.20) vs (3.65 ± 1.77) mGy], dose-length product [(167.10 ± 99.08) mGy•cm vs (113.24 ± 54.46) mGy•cm vs (117.98 ± 32.32) mGy•cm] and effective dose [(2.52 ± 1.39) vs (1.63 ± 0.76) vs (1.73 ± 0.44) mSv] among the groups (P > 0.05). However, groups B and C received similar effective doses but lower iodine loads than group A [(300 vs 450) mgI/kg].CONCLUSIONEICT combined with GSI assist allows differential diagnosis between the T1/2 and T3 stages. The ability to differentially diagnose the T3 and T4 stages of medullary ESCC can be improved by quantitatively and qualitatively analyzing the adipose tissue in front of the vertebral body.

Background: This study aimed to explore the performance of Revolution CT virtual monoenergetic images (VMI) combined with the multi-material artifact reduction (MMAR) technique in reducing metal artifacts in oral and maxillofacial imaging. Results: There were significant differences in image quality scores between VMI + MMAR images and VMI+MARS (multiple artifact reduction system) images at each monochromatic energy level (p = 0.000). Compared with the MARS technology, the MMAR technology further reduced metal artifacts and improved the image quality. At VMI 90 keV and VMI 110 keV , the SD, CNR, and AI in the Revolution CT group were significantly lower than in the Discovery CT, but no significant differences in these parameters were found between two groups at VMI 50 keV , VMI 70 keV , and VMI 130 keV (p > 0.05). The attenuation was comparable between two groups at any energy level (p > 0.05). Conclusions:Compared with the MARS reconstruction technique of Discovery CT, the MMAR technique of Revolution CT is better to reduce the artifacts of dental implants in oral and maxillofacial imaging, which improves the image quality and the diagnostic value of surrounding soft tissues.Compared to the 64-slice Discovery CT VMI + MARS technique for image reconstruction, 256-slice Revolution CT VMI + MMAR technique for image reconstruction is better to reduce metal artifacts and background SD. The combined use of VMI 110 keV + MMAR technique is helpful for the observation and evaluation of small structures around the metal implants. The combined use of VMI 110 keV + MMAR technique also provides a better diagnostic tool in clinical practice.

BACKGROUND The rare incidence of esophageal neuroendocrine carcinoma (NEC) and limited treatment experience result in insufficient clinical observations and unsuitable guidelines for its management. AIM To investigate the prognostic value of pretreatment contrast-enhanced computed tomography (CT) characteristics in patients with esophageal NEC. METHODS Seventy-seven esophageal NEC patients who received contrast-enhanced CT at two hospitals were enrolled in this study from June 2014 to December 2019. The clinical features and image characteristics were recorded accordingly. Univariate survival analysis was performed using the Kaplan-Meier method and log-rank test, and multivariate analysis was carried out with a Cox proportional hazards model. RESULTS The multivariate analysis performed using the Cox proportional hazards model showed that N stage, adjuvant chemotherapy, and degree of enhancement were independent prognostic factors for overall survival (OS). Meanwhile, adjuvant chemotherapy was an independent prognostic factor for progression-free survival (PFS). The hazard ratios (HRs) of N stage, adjuvant chemotherapy, and degree of enhancement (mild vs moderate/marked) for OS were 0.426 ( P = 0.024), 3.862 ( P = 0.006), and 2.169/0.809 ( P = 0.037), respectively. The HR of adjuvant chemotherapy for PFS was 6.432 ( P < 0.001). Adjuvant chemotherapy was significantly associated with degree of enhancement ( P = 0.018). CONCLUSION Adjuvant chemotherapy is an independent prognostic factor for OS and PFS. Additionally, N stage and degree of enhancement are prognostic factors for OS in patients with esophageal NEC.