Objective: Accurate evaluation of inflammation severity in ulcerative colitis (UC) can guide treatment strategy selection. The potential value of the pericolic fat attenuation index (FAI) on CT as an indicator of disease severity remains unknown.This study aimed to assess the diagnostic accuracy of pericolic FAI in predicting UC severity. Materials and Methods: This retrospective study enrolled 148 patients (mean age 48 years; 87 males). The fat attenuation on CT was measured in four different locations: the mesocolic vascular side (MS) and opposite side of MS (OMS) around the most severe bowel lesion, the retroperitoneal space (RS), and the subcutaneous area. The fat attenuation indices (FAI MS, FAI OMS, and FAI RS) were calculated as the fat attenuation measured in MS, OMS, and RS, respectively, minus that of the subcutaneous area, and were obtained in the non-enhanced, arterial, and delayed phases. Correlations between the FAI and UC Endoscopic Index of Severity (UCEIS) were assessed using Spearman’s correlation. Predictors of severe UC (UCEIS ≥7) were selected by univariable analysis. The performance of FAI in predicting severe UC was evaluated using the area under the receiver operating characteristic curve (AUC). Results: The FAIMS and FAI OMS scores were significantly higher than FAI RS in three phases (all P < 0.001). The FAIMS and FAI OMS scores moderately correlated with the UCEIS score (r = 0.474–0.649 among the three phases). Additionally, FAI MS and FAI OMS identified severe UC, with AUC varying from 0.77 to 0.85. Conclusion Increased CT attenuation of pericolic adipose tissue could serve as a noninvasive marker for evaluating UC severity. FAI MS and FAI OMS of three phases showed similar prediction accuracies for severe UC identification.

Objective: Accurate evaluation of inflammation severity in ulcerative colitis (UC) can guide treatment strategy selection. The potential value of the pericolic fat attenuation index (FAI) on CT as an indicator of disease severity remains unknown.This study aimed to assess the diagnostic accuracy of pericolic FAI in predicting UC severity. Materials and Methods: This retrospective study enrolled 148 patients (mean age 48 years; 87 males). The fat attenuation on CT was measured in four different locations: the mesocolic vascular side (MS) and opposite side of MS (OMS) around the most severe bowel lesion, the retroperitoneal space (RS), and the subcutaneous area. The fat attenuation indices (FAI MS, FAI OMS, and FAI RS) were calculated as the fat attenuation measured in MS, OMS, and RS, respectively, minus that of the subcutaneous area, and were obtained in the non-enhanced, arterial, and delayed phases. Correlations between the FAI and UC Endoscopic Index of Severity (UCEIS) were assessed using Spearman’s correlation. Predictors of severe UC (UCEIS ≥7) were selected by univariable analysis. The performance of FAI in predicting severe UC was evaluated using the area under the receiver operating characteristic curve (AUC). Results: The FAIMS and FAI OMS scores were significantly higher than FAI RS in three phases (all P < 0.001). The FAIMS and FAI OMS scores moderately correlated with the UCEIS score (r = 0.474–0.649 among the three phases). Additionally, FAI MS and FAI OMS identified severe UC, with AUC varying from 0.77 to 0.85. Conclusion Increased CT attenuation of pericolic adipose tissue could serve as a noninvasive marker for evaluating UC severity. FAI MS and FAI OMS of three phases showed similar prediction accuracies for severe UC identification.

Objective: Accurate evaluation of inflammation severity in ulcerative colitis (UC) can guide treatment strategy selection. The potential value of the pericolic fat attenuation index (FAI) on CT as an indicator of disease severity remains unknown.This study aimed to assess the diagnostic accuracy of pericolic FAI in predicting UC severity. Materials and Methods: This retrospective study enrolled 148 patients (mean age 48 years; 87 males). The fat attenuation on CT was measured in four different locations: the mesocolic vascular side (MS) and opposite side of MS (OMS) around the most severe bowel lesion, the retroperitoneal space (RS), and the subcutaneous area. The fat attenuation indices (FAI MS, FAI OMS, and FAI RS) were calculated as the fat attenuation measured in MS, OMS, and RS, respectively, minus that of the subcutaneous area, and were obtained in the non-enhanced, arterial, and delayed phases. Correlations between the FAI and UC Endoscopic Index of Severity (UCEIS) were assessed using Spearman’s correlation. Predictors of severe UC (UCEIS ≥7) were selected by univariable analysis. The performance of FAI in predicting severe UC was evaluated using the area under the receiver operating characteristic curve (AUC). Results: The FAIMS and FAI OMS scores were significantly higher than FAI RS in three phases (all P < 0.001). The FAIMS and FAI OMS scores moderately correlated with the UCEIS score (r = 0.474–0.649 among the three phases). Additionally, FAI MS and FAI OMS identified severe UC, with AUC varying from 0.77 to 0.85. Conclusion Increased CT attenuation of pericolic adipose tissue could serve as a noninvasive marker for evaluating UC severity. FAI MS and FAI OMS of three phases showed similar prediction accuracies for severe UC identification.

Objective: Accurate evaluation of inflammation severity in ulcerative colitis (UC) can guide treatment strategy selection. The potential value of the pericolic fat attenuation index (FAI) on CT as an indicator of disease severity remains unknown.This study aimed to assess the diagnostic accuracy of pericolic FAI in predicting UC severity. Materials and Methods: This retrospective study enrolled 148 patients (mean age 48 years; 87 males). The fat attenuation on CT was measured in four different locations: the mesocolic vascular side (MS) and opposite side of MS (OMS) around the most severe bowel lesion, the retroperitoneal space (RS), and the subcutaneous area. The fat attenuation indices (FAI MS, FAI OMS, and FAI RS) were calculated as the fat attenuation measured in MS, OMS, and RS, respectively, minus that of the subcutaneous area, and were obtained in the non-enhanced, arterial, and delayed phases. Correlations between the FAI and UC Endoscopic Index of Severity (UCEIS) were assessed using Spearman’s correlation. Predictors of severe UC (UCEIS ≥7) were selected by univariable analysis. The performance of FAI in predicting severe UC was evaluated using the area under the receiver operating characteristic curve (AUC). Results: The FAIMS and FAI OMS scores were significantly higher than FAI RS in three phases (all P < 0.001). The FAIMS and FAI OMS scores moderately correlated with the UCEIS score (r = 0.474–0.649 among the three phases). Additionally, FAI MS and FAI OMS identified severe UC, with AUC varying from 0.77 to 0.85. Conclusion Increased CT attenuation of pericolic adipose tissue could serve as a noninvasive marker for evaluating UC severity. FAI MS and FAI OMS of three phases showed similar prediction accuracies for severe UC identification.

Objective: Accurate evaluation of inflammation severity in ulcerative colitis (UC) can guide treatment strategy selection. The potential value of the pericolic fat attenuation index (FAI) on CT as an indicator of disease severity remains unknown.This study aimed to assess the diagnostic accuracy of pericolic FAI in predicting UC severity. Materials and Methods: This retrospective study enrolled 148 patients (mean age 48 years; 87 males). The fat attenuation on CT was measured in four different locations: the mesocolic vascular side (MS) and opposite side of MS (OMS) around the most severe bowel lesion, the retroperitoneal space (RS), and the subcutaneous area. The fat attenuation indices (FAI MS, FAI OMS, and FAI RS) were calculated as the fat attenuation measured in MS, OMS, and RS, respectively, minus that of the subcutaneous area, and were obtained in the non-enhanced, arterial, and delayed phases. Correlations between the FAI and UC Endoscopic Index of Severity (UCEIS) were assessed using Spearman’s correlation. Predictors of severe UC (UCEIS ≥7) were selected by univariable analysis. The performance of FAI in predicting severe UC was evaluated using the area under the receiver operating characteristic curve (AUC). Results: The FAIMS and FAI OMS scores were significantly higher than FAI RS in three phases (all P < 0.001). The FAIMS and FAI OMS scores moderately correlated with the UCEIS score (r = 0.474–0.649 among the three phases). Additionally, FAI MS and FAI OMS identified severe UC, with AUC varying from 0.77 to 0.85. Conclusion Increased CT attenuation of pericolic adipose tissue could serve as a noninvasive marker for evaluating UC severity. FAI MS and FAI OMS of three phases showed similar prediction accuracies for severe UC identification.

Objective:To investigate the application value of magnetic resonance imaging(MRI) in evaluating the efficacy of anti-PD-1 combined with neoadjuvant therapy for microsatellite stability (MSS)/proficient mismatch repair (pMMR) locally advanced rectal cancer (LARC).Methods:The prospective single-arm phase Ⅱ study was conducted. The clinicopathological data of 37 patients with MSS/pMMR LARC who were admitted to Beijing Friendship Hospital of Capital Medical University from April 2021 to September 2022 were collected. All patients underwent anti-PD-1 combined with neoadjuvant therapy and radical total mesorectal excision. Observation indicators: (1) enrolled pati-ents; (2) MRI and pathological examination; (3) concordance analysis of MRI examination reading; (4) evaluation of MRI examination. Measurement data with normal distribution were represented as Mean± SD. Count data were expressed as absolute numbers or percentages. Linear weighted κ value was used to evaluate the concordance of radiologist assessment. Sensitivity, negative predictive value, accuracy, overstaging rate and understaging rate were used to evaluate the predictive value. Results:(1) Enrolled patients. A total of 37 eligible patients were screened out, including 21 males and 16 females, aged (61±11)years. MRI examination was performed before and after combined therapy, and pathological examination was performed after radical resection. (2) MRI and pathological examination of patients. Among the 37 patients, MRI before combined therapy showed 0, 0, 5, 24 and 8 cases in stage T0, T1, T2, T3 and T4, 10, 17 and 10 cases in stage N0, N1 and N2, 28 and 9 cases of positive and negative extramural vascular invasion (EMVI), 4 and 33 cases of positive and negative mesorectal fascia (MRF), respectively. MRI examination after combined therapy showed 15, 4, 7, 10 and 1 cases in stage T0, T1, T2, T3 and T4, 34, 2 and 1 cases in stage N0, N1 and N2, 9 and 28 cases of positive and negative EMVI, 1 and 36 cases of positive and negative MRF. There were 16, 13, 8 and 0 cases of tumor regression grading (TRG) 0, 1, 2 and 3, respectively. Postoperative pathological examination showed 18, 4, 3, 11, 1 cases in stage T0, T1, T2, T3, T4, 33, 3, 1 cases in stage N0, N1, N2, positive and negative EMVI and unknown data in 1, 35, 1 cases, positive and negative circumferential margin in 0 and 37 cases, grade 0, grade 1, grade 2, grade 3 of American Joint Committee on Cancer TRG in 18, 9, 8, 2 cases, respectively. Pathological complete response rate was 48.6%(18/37) and approximate pathological complete response rate was 24.3%(9/37). (3)Concordance analysis of MRI examination reading. The κ value of T staging and N staging on MRI before combined therapy was 0.839 ( P<0.05) and 0.838 ( P<0.05), respectively. The κ value of T staging and N staging on MRI after combined therapy was 0.531 ( P<0.05) and 0.846 ( P<0.05), respectively. The κ value of EMVI and MRF was 0.708 ( P<0.05) and 0.680 ( P<0.05) before combined therapy, and they were 0.561 ( P<0.05) and 1.000 ( P<0.05) after combined therapy, respectively. The κ value of TRG 3-round reading for TRG was 0.448 ( P<0.05). (4) Evaluation of MRI examination. ① MRI evaluation of T and N staging. The accuracy of MRI examination after combined therapy for distinguishing stage T0 was 75.7%[28/37, 95% confidence interval ( CI) as 62.2%-89.2%], the understaging rate was 8.1%(3/37, 95% CI as 0-18.9%), the overstaging rate was 16.2%(6/37, 95% CI as 5.4%-29.7%). The accuracy of MRI examination for distinguishing stage T0-T2 was 86.5%(32/37, 95% CI as 73.0%-97.3%), its understaging rate and overstaging rate were 8.1%(3/37, 95% CI as 0-18.9%) and 5.4% (2/37, 95% CI as 0-13.5%), respectively. The accuracy of MRI examination for distinguishing N staging was 91.9%(34/37, 95% CI was 81.1%-100.0%), its understaging rate and overstaging rate were 5.4%(2/37, 95% CI as 0-13.5%) and 2.7%(1/37, 95% CI as 0-8.1%), respectively. Among 18 patients in pathological stage T0, the overstaging rate of MRI was 33.3%(6/18). All the 4 patients in pathological stage T1 and 3 pati-ents in pathological stage T2 had correct diagnosis. There were 3 cases with understaging among 12 patients in pathological stage T3-T4. Among the 37 patients in pathological stage N0-N2, 34 cases had correct diagnosis, 1 case was overstaged as stage N1 due to a round mesorectal lymph node with short diameter as 6 mm, and 2 cases were diagnosed as stage N0 due to the small lymph nodes with the maximum short diameter as 3 mm. ② MRI evaluation of EMVI and MRF. The accuracy, sensitivity and negative predictive value of MRI for evaluating EMVI were 86.5%(32/37, 95% CI as 75.0%-97.2%), 100.0% and 100.0%, respectively, and the overestimation rate of EMVI was 13.9%(5/36, 95% CI as 2.8%-25.0%), and no underestimation occurred. Of 35 pathologically negative EMVI patients, a rate of 14.3%(5/35) of patients were positive on MRI. The main reason for overestaging was that thickened fibrous tissue outside the rectal wall was mistaken for vascular invasion. The accuracy of MRI for evaluating MRF was 97.3%(36/37, 95% CI as 91.9%-100.0%), and 1 case (1/37, 2.7%, 95% CI as 0-8.1%) was overestimated as positive MRF due to misdiagnosis of pararectal MRF lymph nodes. The negative predictive value of MRI for assessing MRF was 100.0%. ③ MRI evaluation of TRG. The accuracy, understaging and overstaging rates of MRI for evaluating pathological TRG 0 were 78.4%(29/37, 95% CI as 64.9%-91.9%), 8.1%(3/37, 95% CI as 0-18.9%), 13.5%(5/37, 95% CI as 5.4%-27.0%), respectively. The accuracy, understaging and overstaging rates of MRI for evaluating pathological TRG 0-1 were 89.2%(33/37, 95% CI as 78.4%-97.3%), 8.1%(3/37, 95% CI as 0-18.9%), 2.7%(1/37, 95% CI as 0-8.1%), respectively. Of the 18 patients with pathologic complete response, 5 cases were diagnosed as pathological TRG 1 and 13 cases as pathological TRG 0. One near-pCR patient was assessed as pathological TRG 2. Two patients with pathological TRG 3 were incorrectly diagnosed on MRI. Conclusions:Anti-PD-1 combined with neoadjuvant therapy can downstage the LARC pati-ents with MSS/pMMR. MRI is effective in predicting T staging, N staging, EMVI, MRF and TRG. However, overstaging should be prevented.

Purpose To evaluate the value of MRI T1 mapping combined with biliary tract paravertebral muscle signal intensity ratio in liver function.Materials and Methods A total of 72 patients with Gd-EOB-DTPA enhanced MRI were prospectively collected in Beijing Friendship Hospital from August 2020 to February 2022 and divided into three groups according to Child-Pugh classification of liver function:22 patients in normal liver function group,35 patients in grade A group and 15 patients in grade B+C group.The T1 mapping sequence was scanned in all patients before and 20 min after enhancement to measure the pre-enhancement and post-enhancement(T1post)T1 relaxation time of liver parenchyma,and the reduction rate of liver T1 relaxation time(ΔT1)was calculated.Biliary tract signal and paravertebral muscle signal were measured on hepatobiliary stage images,and biliary tract paravertebral muscle signal intensity ratio(SIR)was calculated.The consistency of measurement results among physicians was evaluated.The correlation between each index and liver function grade was observed.The differences among different groups were compared.The diagnostic efficiency of each image index were evaluated.Results T1post was positively correlated with liver function grade(r=0.683,P<0.001),and it increased gradually with the severity of liver function impairment.ΔT1,SIR,SIR×ΔT1 were negatively correlated with liver function grade(r=-0.764,-0.729,-0.826,all P<0.001),and gradually decreased with the severity of liver function impairment.T1post,ΔT1,SIR,SIR×ΔT1 had statistical significance in liver function classification among all groups(F=27.491,55.782,48.410,46.809,all P<0.05).In pairwise comparison,the differences of each index were also statistically significant(P<0.05).The best diagnostic efficacy of each index was SIR×ΔT1,and the area under the curve of normal liver function group and cirrhosis group,grade A group and grade B+C group were 0.915 and 0.984,respectively.Conclusion T1post,ΔT1,SIR and SIR×ΔT1 are strongly correlated with Child-Pugh grade of liver function.SIR×ΔT1 can be used as an imaging index for quantitative evaluation of liver function.

Hepatocellular carcinoma (HCC) is the most common primary malignant tumor of the liver. MRI has become an important imaging method for non-invasive diagnosis and evaluation of HCC in clinics because of its advantageous aspects, such as its non-radiative nature, superior detection, and qualitative accuracy over CT and ultrasound. Various MRI techniques, including hepatobiliary-specific contrast agents, magnetic resonance elastography, diffusion-weighted imaging, and others, can diagnose HCC or evaluate its malignant biological behavior from different dimensions such as blood supply, cell function, tissue hardness, and water molecule diffusion. This article introduces the current status and prospects of various MRI techniques for HCC diagnosis and evaluation.

Objective:To investigate the hemodynamic characteristics of transverse sinus with sigmoid sinus wall dehiscence (SSWD) of pulsatile tinnitus (PT) based on 4D flow MRI.Methods:Retrospective analysis was performed on all patients admitted to Beijing Friendship Hospital, Capital Medical University from January 2019 to January 2021 for dehiscent sigmoid plate pulsatile tinnitus. A total of 26 patients (sides) who met the criteria and underwent 4D flow MRI were included. A total of 26 subjects (46 sides), matched 1∶1 according to gender and age, were included in the normal healthy control group. Nonparametric rank sum test, Student′s t test, and ANOVA were performed by SPSS 19.0 software. Binary Logistic regression was applied to the data with statistical significance. Results:There were more patients with dominant drainage on the affected side in PT group than in control group (73.1% vs. 42.3%). The incidence of transverse with a focal intraluminal filling defect and tapered stenosis was higher than that in control group (21.7% vs. 69.2%; 17.4% vs. 42.3%). Average through-plane velocity and maximum through-plane velocity in PT group were higher than those in control group [(33.75±13.88) cm/s vs. (15.84±7.21) cm/s; (93.19±33.55) cm/s vs. (40.40±14.40) cm/s]. The middle part and proximal end of Flow avg (ml/s) in PT group were larger than those in control group [4.69 (2.87; 5.62) ml/s vs. 2.76 (1.67; 4.99) ml/s; 3.41 (2.16; 5.47) ml/s vs. 2.67 (1.68; 4.41) ml/s]. In control group, the velocity of transverse sinus changed relatively gently, while in PT group, the velocity of proximal sinus increased significantly. Binary Logistic regression showed that SSWD PT was independently correlated with proximal maximum flow velocity [ OR=1.086(1.029-1.146), P=0.003]. Conclusion:4D flow MRI showed that the dominant drainage and higher velocity at the proximal end of the transverse sinus might be an important hemodynamic characteristics of dehiscent sigmoid plate pulsatile tinnitus.