OBJECTIVE To compare the ability of ultra-high-resolution CT(U-HRCT)and multi-slice spiral CT(MSCT)to display key vocal transmission structures in the middle ear.METHODS Subjects with normal middle ear structures who underwent 0.1 mm layer thickness U-HRCT and 0.625 mm layer thickness MSCT scans at the same time in Beijing Friendship Hospital affiliated to Capital Medical University from December 2019 to August 2024 were retrospectively enrolled.Two experienced head and neck radiologists reconstruct standard transsectional,coronal images based on the thinnest layer thickness.According to the 5-point method,16 key sound transmission structures of the middle ear,including malleus,incus and stapes,as well as joints,ligaments and tendons,were evaluated for image quality scoring.The standard deviation(SD)value,signal noise ratio(SNR),and contrast noise ratio(CNR)of bone in the malleus region and intratympanic gas were measured and calculated on the two examination images.RESULTS Thirty patients(47 sides)with normal middle ear structure were included,including 18 males and 12 females.The two physicians compared the results of U-HRCT in showing malleus head,malleus neck,malleus handle,incus body,long process,and short process,5 points accounted for 100%,and the 5-point scores of incudomalleolar joint space,incudostapedial joint space,stapes footplate and annular ligament were 100%,98.29%,75.83%and 77.83%,respectively,which were significantly higher than those of MSCT(P<0.001).In addition,U-HRCT showed higher scores for lenticular process,stapes head,anterior arch of stapes,posterior arch of stapes,annular ligament,stapes muscle,and tendo musculi tensoris tympani than MSCT(P<0.001),and the lenticular process showed a 100%display rate.There was no significant difference in the SNR between the two groups(P>0.05),but the SD value of the malleus in U-HRCT was 161.6±36.4,which was significantly lower than that in MSCT(297.8±128.1),and the difference was statistically significant(P<0.001).CONCLUSION U-HRCT can clearly visualize the key sound transmission structures of the middle ear,and its visualization ability is significantly better than that of MSCT.

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 evaluate the relationship between transverse sinus stenosis (TSS) and cerebral blood flow in normal adults based on four-dimensional flow (4D Flow) MRI.Methods:The study was a cross-sectional study. Totally 81 normal volunteers who underwent magnetic resonance venography (MRV) and 4D Flow MRI were prospectively enrolled at Beijing Friendship Hospital, Capital Medical University from January 2020 to December 2022. Based on MRV evaluation of transverse sinus dysplasia, the volunteers were divided into a dysplasia group (26 cases) and a non-dysplasia group (55 cases); The area of the stenosis and the normal transverse sinus at the distal end were measured. The degree of TSS and the bilateral average transverse sinus stenosis (BA-TSS) were calculated. TSS was determined using TSS levels of 1/3, 1/2, and 2/3 as thresholds, and was divided into three groups: no TSS group, unilateral TSS group, and bilateral TSS group, with 28, 39, and 14 cases, 37, 37, and 7 cases, and 43, 36, and 2 cases, respectively. Based on 4D Flow MRI, the blood flow of the internal carotid artery, vertebral artery, superior sagittal sinus, straight sinus, and transverse sinus distal and proximal ends were measured. The cerebral blood flow (bilateral internal carotid artery blood flow+bilateral vertebral artery blood flow), venous sinus return blood flow 1 (superior sagittal sinus blood flow+straight sinus blood flow), return blood flow 2 (sum of bilateral transverse sinus distal end blood flow), return blood flow 3 (sum of bilateral transverse sinus proximal end blood flow), and the ratio of return blood flow to cerebral blood flow were calculated. Independent sample t-test was used to compare the differences between the group with and without transverse sinus dysplasia; Single factor analysis of variance was used to compare the differences between the TSS free group, unilateral TSS group, and bilateral TSS group. Based on single factor linear regression, the relationships between BA-TSS and blood flow parameters were analyzed.Results:There was no statistically significant difference in various blood flow parameters between the group with and without transverse sinus dysplasia (all P>0.05). When using 1/3, 1/2, and 2/3 as thresholds, there was no statistically significant difference in various blood flow parameters between the non TSS group, unilateral TSS group, and bilateral TSS group (all P>0.05). BA-TSS was linearly positively correlated with cerebral blood flow (β=0.986, 95% CI 0.108-1.865, P=0.028), but not linearly correlated with return blood flow 1, 2, and 3 (all P>0.05). The degree of BA-TSS was linearly negatively correlated with return blood flow 1/cerebral blood flow (β=-0.001, 95% CI -0.002-0, P=0.009) and return blood flow 2/cerebral blood flow (β=-0.001, 95% CI -0.002-0, P=0.018), but not with return blood flow 3/cerebral blood flow ( P=0.076). Conclusion:The BA-TSS degree in normal adults is positively correlated with cerebral blood inflow and negatively correlated with the proportion of venous sinus outflow.

Objective:To investigate the role of a modified positioning device in improving image quality and diagnostic efficacy for thyroid cancer in contrast-enhanced neck CT imaging.Methods:This prospective cross-sectional study included 137 patients with pathologically confirmed thyroid lesions who underwent contrast-enhanced neck CT at Zhangzhou Affiliated Hospital of Fujian Medical University from January to April 2024. Patients scanned in January and February (modified positioning group, n=62) underwent scanning using the modified positioning device, whereas those scanned in March and April (traditional positioning group, n=75) underwent scanning with conventional positioning. The estimated volume CT dose index (CTDI vol) in the thyroid region was recorded. Subjective image quality for thyroid and neck regions was evaluated using a 5-point Likert scale. Diagnostic assessments for thyroid cancer, capsule invasion, and lymph node metastasis were independently conducted by one junior radiologist and one senior radiologist using a 5-point scoring system, with scores≥3 considered positive diagnoses. The differences of CTDI vol and image quality scores between the 2 groups were compared using Mann-Whitney U test. The diagnostic performance was evaluated by the receiver operating characteristic curve analysis. Results:The estimated CTDI vol values for the thyroid region were significantly lower in the modified positioning group compared to the traditional positioning group [11.20 (8.37, 13.56) vs. 12.46 (10.10, 19.43) mGy, Z=1.99, P=0.026]. Subjective image quality scores for thyroid and neck regions were significantly higher in the modified positioning group than in the traditional positioning group (all P<0.001). For thyroid cancer diagnosis by the senior radiologist, the modified positioning group had a significantly higher area under the curve (AUC) of 0.842 (95% CI 0.728-0.956) compared to the traditional positioning group (AUC=0.666,95% CI 0.554-0.777, Z=2.17, P=0.031). No significant differences were observed in diagnostic performance between the junior and senior radiologists for thyroid cancer, capsule invasion, and lymph node metastasis in other subgroup comparisons (all P>0.05). Conclusion:The modified positioning device using in contrast-enhanced neck CT imaging can improve image quality and diagnostic efficacy for thyroid cancer while reducing radiation exposure to the thyroid gland.

Objective To investigate the imaging features and causes of missed diagnosis of colorectal cancer(CRC)in routine abdomi-nopelvic CT examinations.Methods A retrospective analysis was conducted on the clinical and imaging data of 38 patients with CRC which were initially overlooked in routine abdominopelvic CT examinations.The imaging features and causes of missed diagnosis were analyzed.Results Distribution of lesions:ten cases(26.3％)located in the caecum-ascending colon,6 cases(15.8％)located in the transverse colon,1 case(2.6％)located in the descending colon,18 cases(47.4％)located in the sigmoid colon and 3 cases(7.9％)located in the rectum.The mean length of diseased bowel was(2.8±1.3)cm.Pericolic fat stranding was found in 16 cases,locore-gional adenopathy was found in 19 cases,and focal pericolic neovascularity was found in 12 cases.The four reasons for missed diagno-sis included:(1)comprehensive assessment of colorectal conditions was not routinely performed;(2)small lesion size;(3)unfamiliar with the subtle secondary signs of CRC;(4)image-related reasons.Conclusion Radiologists should conduct conventional and com-prehensive assessment of the colorectum in routine abdominopelvic CT examinations.With the accumulation of diagnostic experience,it will be beneficial to reduce the missed diagnosis rate of CRC.

Purpose To measure the spatial resolution in MRI quality control testing automatically based on the American College of Radiology(ACR)phantom using the support vector machine(SVM)method,and the feasibility,accuracy and measurement speed of this method are explored.Materials and Methods Quality control tests were performed using eight MRI devices at Beijing Friendship Hospital of Capital Medical University.A retrospective study was conducted on 71 MRI quality control test images collected based on ACR phantoms between 2017 and 2019.The images were preprocessed by binarization,extraction region of interest and so on.An SVM-based classification model was constructed for analyzing the spatial resolution of dot arrays in row and column directions.The dataset was randomly split into a training set and a test set.The generalization performance of the classification model in this study was evaluated through accuracy,precision,recall and F1 score on the test set.Comparing the results of spatial resolution measurements obtained by both manual and automatic method,we demonstrated the feasibility and accuracy of the method.Additionally,the time taken for the automatic spatial resolution measurement was recorded.Results In this study,the proposed method of automatically measuring the spatial resolution of ACR phantom test images using SVM was feasible,high accuracy and short time.In classification performance test,the accuracy of the spatial resolution of the row directional latices was 95%,the precision was 100%.The accuracy of the spatial resolution of the column directional latices was 97%,the precision was 100%.Among the test cases,the results of automatic measurements matched those of manual measurements in 13 out of 14 cases.On average,automatic spatial resolution measurement took 0.158 seconds per case.Conclusion This study achieves automatic measurement of spatial resolution in MRI quality control based on the ACR phantom using SVM method.The method demonstrates high accuracy and fast measurement speeds,holding significant implications for future rapid MRI quality control stability testing.