Is non-contrast-enhanced magnetic resonance imaging cost-effective for screening of hepatocellular carcinoma?

INTRODUCTION@#Ultrasonography (US) is the current standard of care for imaging surveillance in patients at risk of hepatocellular carcinoma (HCC). Magnetic resonance imaging (MRI) has been explored as an alternative, given the higher sensitivity of MRI, although this comes at a higher cost. We performed a cost-effective analysis comparing US and dual-sequence non-contrast-enhanced MRI (NCEMRI) for HCC surveillance in the local setting.@*METHODS@#Cost-effectiveness analysis of no surveillance, US surveillance and NCEMRI surveillance was performed using Markov modelling and microsimulation. At-risk patient cohort was simulated and followed up for 40 years to estimate the patients' disease status, direct medical costs and effectiveness. Quality-adjusted life years (QALYs) and incremental cost-effectiveness ratio were calculated.@*RESULTS@#Exactly 482,000 patients with an average age of 40 years were simulated and followed up for 40 years. The average total costs and QALYs for the three scenarios - no surveillance, US surveillance and NCEMRI surveillance - were SGD 1,193/7.460 QALYs, SGD 8,099/11.195 QALYs and SGD 9,720/11.366 QALYs, respectively.@*CONCLUSION@#Despite NCEMRI having a superior diagnostic accuracy, it is a less cost-effective strategy than US for HCC surveillance in the general at-risk population. Future local cost-effectiveness analyses should include stratifying surveillance methods with a variety of imaging techniques (US, NCEMRI, contrast-enhanced MRI) based on patients' risk profiles.

Correlation of mRNA expression levels and DNA methylation levels of APTR with HBV infection / 中华临床感染病杂志

Objective:To investigate the correlation of mRNA expression levels and DNA methylation levels of Alu-mediated p21 transcriptional regulator (APTR) with hepatitis B virus infection.Methods:One hundred patients with HBV infection admitted in Affiliated Hospital of Yunnan University during January to December 2019 were enrolled in the study, including 50 patients with chronic hepatitis B (CHB group) and 50 asymptomatic HBV carriers (ASC group); and 50 healthy subjects were also enrolled as the healthy control group. The DNA methylation levels of APTR gene were detected by methylation-sensitive high-resolution melting (MS-HRM); the expression levels of APTR mRNA were detected by fluorescence real-time quantitative PCR (qRT-PCR). Pearson correlation or Spearman rank correlation was used for correlation analysis.Results:There were significant differences in the APTR DNA methylation levels among the CHB, ASC and healthy control groups {[12.02 (9.30, 23.32)]%, [10.02 (8.46, 17.44)]% and [8.86 (7.82, 11.57)]%, χ2=13.360, P<0.01}. The APTR DNA methylation levels were significantly higher in CHB group than those in healthy control group( Z=31.480, P<0.01). There were significant differences in the APTR mRNA expression levels among CHB, ASC and healthy control groups (2.38±1.41, 5.78±2.78 and 5.70±2.66, F=33.720, P<0.01). The APTR mRNA expression levels were significantly lower in CHB group than those in healthy control and ASC groups ( t=7.808 and 7.724, both P<0.01). Correlation analysis showed that the DNA methylation level of APTR gene was negatively correlated with mRNA expression levels ( r=-0.305, P<0.01) in all subjects. The DNA methylation level of APTR gene was positively correlated with HBsAg level ( r=0.231, P=0.022), and the mRNA expression level was negatively correlated with HBsAg level ( r=-0.245, P=0.014) in patients with HBV infection. Conclusion:There are differences in DNA methylation and mRNA expression of APTR gene in different stages of HBV infection, suggesting that APTR gene may be involved in the immune regulation of HBV infection.

Value of novel dual-layer spectral detector CT in preoperative T staging of rectal cancer / 中华放射学杂志

Objective:To explore the optimal keV for the visualization of rectal cancer and to investigate its diagnostic performance in the preoperative T staging of rectal cancer using virtual monoenergetic image (VMI) on a novel dual-layer spectral detector CT.Methods:Totally 43 patients with pathologically confirmed rectal cancer were involved in this retrospective study in Ruijin Hospital, Shanghai Jiao Tong University School of Medicine from May to October 2019. All the patients underwent novel dual-layer spectral detector CT scanning within 1 week before surgery. The 40, 50, 60, 70 keV VMI and 120 kVp conventional polyenergetic image (PI) were reconstructed based on the venous phase imagings. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the rectal cancer were measured and the image quality was scored using a 5-point scale to obtain the best keV VMI. Taking pathological results as golden standard, the accuracy rate of T staging was calculated and compared between the best keV VMI and 120 kVp PI. The CT attenuation, SNR and CNR were compared with one-way ANOVA analysis among the 5 groups of images.Image quality scores were assessed with Friedman test,and the accuracy rate was compared by McNemar test or Fisher exact test.Results:The SNR and CNR of rectal cancer at 40-70 keV VMI was better than 120 kVp PI ( P<0.05), the SNR at 40 keV VMI was the highest among all the VMI ( P<0.05), the CNR at 40 keV VMI was better, but there was no significant difference between 40 and 50 keV VMI ( P>0.05). The image scores at 40-60 keV VMI were all significantly superior to those of the 120 kVp PI ( P<0.001). 40 keV VMI was the best image. The accuracy rate of 40 keV VMI (67.4%, 29/43) was higher than that of 120 kVp PI (48.8%, 21/43) in the T stage ( P=0.008). The 40 keV VMI had a higher diagnostic accuracy rate (83.7%, 36/43) and specificity （58.8%, 10/17） in diagnosis of locally advanced rectal cancer (T3-4, P=0.016, 0.031). Conclusion:The image quality of novel dual-layer spectral detector CT at 40 keV VMI is good, which can improve the accuracy rate of preoperative T staging of rectal cancer.

Clinics in diagnostic imaging (197). Left ischiofemoral impingement syndrome

A 48-year-old woman presented with progressive left hip pain over six months, along with left lower limb weakness for two weeks. Magnetic resonance imaging of the left hip showed narrowing of the left ischiofemoral space, oedema of the left quadratus femoris muscle and left sciatic nerve, and mild bone marrow oedema of the left ischial tuberosity. The diagnosis of left ischiofemoral impingement syndrome was made. The imaging features of ischiofemoral impingement syndrome and the associated aetiologies and complications are discussed.