Maximum Cross-sectional Area Research Articles

The Effect of Steel Reinforcement Diameter on the Behavior of Concrete Beams with Corrosion

Corrosion is one of the main problems affecting reinforced concrete (RC) structures, yet there remains a lack of studies in which the electrochemical and structural behavior of corroded RC elements are studied together. In this work, four RC beams with and without corrosion were studied to evaluate their electrochemical and structural behavior via the variable of the diameter of the longitudinal tension steel reinforcement (LTR). The beams were initially tested to determine their initial structural behavior and then subjected to sustained loads and wetting and drying cycles by applying a NaCl solution. The beams were tested a second time to determine their final structural behavior. The variations in the corrosion potential and corrosion rate of the LTR with time, together with concrete resistivity, cracking patterns, and load–displacement curves of the RC beam, are presented. It was found that the electrochemical parameters of the beams with corrosion were similar regardless of the steel reinforcement diameter; these parameters indicated a high level of corrosion. The maximum flexural strength loss was observed for beams with an LTR of 10 mm compared to those with a 13 mm diameter. The maximum cross-sectional area loss associated with pitting corrosion was greater for the beam with an LTR of 10 mm.

Comparative analysis of small-incision and traditional techniques in costal cartilage harvesting: Outcomes on thoracic deformities and scar appearance.

This study aims to compare the postoperative thoracic deformity and scar aesthetic outcomes of auricular reconstruction between the conventional large-incision technique and small-incision technique with perichondrium preservation for costal cartilage harvesting. A retrospective analysis was performed on 134 patients who underwent auricular reconstruction using tissue expanders and autologous costal cartilage harvested from the right chest wall between January 2021 and September 2023. Patients were divided into two groups according to the harvesting technique: the traditional large-incision group (n=64) and the small-incision group with perichondrium preservation (n=70). Preoperative and postoperative chest CT scans were reviewed for thoracic deformities by measurements of the modified Haller Index (mHI) and modified correction index (mCI). Thoracic scar dimensions were measured in postoperative follow-up. In the conventional group, significant difference were observed between the left and right hemithorax in anterior-posterior diameter, maximum transverse diameter, cross-sectional area, and mHI values (p<0.05), showing thoracic deformities. In contrast, within the small-incision group, there were no significant differences between hemithoraces. Additionally, postoperative thoracic scars were significantly smaller in the small-incision group, with shorter scar length (5.63±1.33 cm vs. 11.44±1.31cm) and width (1.41±0.55cm vs. 3.75±1.54cm; p<0.001). The small-incision technique with perichondrium preservation significantly reduces postoperative thoracic deformities and results in smaller, less conspicuous scars compared to the traditional large-incision method. This approach minimizes disruption to the chest wall structure and reduces donor-site morbidity, offering improved patient outcomes.

Analysis of imaging risk factors for prognosis in children with spinal cord injury without radiologic abnormalities

This study aimed to identify imaging risk factors for spinal cord injury without radiologic abnormalities (SCIWORA) in children. We retrospectively analyzed the medical records and magnetic resonance imaging (MRI) findings of children with SCIWORA admitted to our hospital between January 1, 2012, and September 30, 2022. Univariate and binary logistic regression analyses were used to evaluate the prognostic impact of various factors including MRI type, maximum cross-sectional area of spinal cord injury, injury length, injury signal intensity ratio. The American Spinal Injury Association (ASIA) impairment scale (AIS) was used to assess neurological improvement of spinal cord injury. A total of 39 patients met the inclusion criteria, comprising three males and 36 females aged 6.38 ± 1.7 years. The injuries were predominantly dance-related (25 patients), followed by car accidents (4 patients), and falls/sprains (10 patients). Seventeen patients showed improvement in the AIS grade, while 22 did not. Binary logistic regression analysis revealed that the maximum cross-sectional area and length of the damaged segment were significant prognostic factors. Receiver operating characteristic curve analysis demonstrated an area under the curve (AUC) of 0.91, with a maximum cutoff value, sensitivity, and specificity of 0.12, 81.80%, and 88.20%, respectively, for the maximum damage cross-sectional area. For the damaged segment length, the AUC, maximum cutoff value, sensitivity, and specificity were 0.78, 6.50, 50%, and 41%, respectively. Whole-spine MRI plays a crucial role in the diagnosis and prognosis of pediatric patients with SCIWORA. The cross-sectional area and length of spinal cord injury are risk factors for poor prognosis.Level of evidence: IV

Patterns of Extraocular Muscle Enlargement in Graves' Orbitopathy and Acromegaly.

Purpose: Extraocular muscle (EOM) enlargement occurs in both acromegaly and Graves' disease, but the degree and pattern of enlargement have not been directly compared in these patient groups. This study investigated whether acromegaly and Graves' orbitopathy (GO) are associated with different patterns of EOM enlargement at the time of diagnosis. Study Design: Retrospective cohort. Methods: All new patients with a diagnosis of acromegaly or GO who presented to St Joseph's Health Care in London, Ontario, between January 1, 2015, and July 1, 2020, and who underwent computed tomography (CT) scanning with adequate orbital imaging were considered for inclusion. We included age- and sex-matched control patients with pituitary macroadenomas without thyroid or growth hormone abnormalities. Orbital CT scans were analyzed by a single neuroradiologist, who measured the maximum diameter and cross-sectional area of each EOM. The relative likelihood of involvement of each rectus EOM was analyzed separately using an analysis of variance test. Results: We included 16 patients with GO, 17 with acromegaly, and 18 controls. Ages (mean ± standard deviation) of groups were 55.6 ± 18.0, 50.2 ± 15.7, and 49.3 ± 14.0 years. The mean maximum diameter of EOMs in GO, acromegaly, and controls was inferior rectus (IR) = 4.77 ± 1.53, 4.66 ± 0.61, and 3.68 ± 0.61 mm; medial rectus (MR) = 5.35 ± 2.23, 4.84 ± 0.81, and 3.65 ± 0.42 mm; superior rectus (SR) = 4.94 ± 1.84, 4.88 ± 0.91, and 3.68 ± 0.61 mm; and lateral rectus (LR) = 3.91 ± 1.59, 4.55 ± 0.60, and 3.20 ± 0.43 mm. The IR, MR, and SR muscles were significantly larger in the GO group compared with controls (IR, p = 0.020; SR, p = 0.004; MR, p < 0.001; and LR, p = 0.166), and all four EOMs were larger in acromegaly compared with controls (IR, p = 0.039; SR, p = 0.006; MR, p = 0.006; and LR, p = 0.001). There was no significant difference between the GO and acromegaly groups (IR, p = 0.959; SR, p = 0.987; MR, p = 0.408; and LR, p = 0.250). Conclusions: GO and acromegaly groups demonstrated the enlargement of the IR, MR, and SR muscles when compared with controls. The GO group did not show significantly larger EOM sizes compared with the acromegaly group. In the GO group, the IR, MR, and SR were similarly affected and did not follow previously described patterns of enlargement in GO.

Factors Affecting Liver Function Abnormalities After Laparoscopic Esophageal Hiatal Hernia Repair.

In this study, we investigated the factors related to abnormal liver function in patients undergoing laparoscopic esophageal hiatal hernia repair. The clinical data of 347 patients who underwent elective laparoscopic esophageal hiatal hernia repair at Beijing Chao-yang Hospital of Capital Medical University between January 2018 and November 2023 were retrospectively collected. The patients comprised 131 males and 216 females, ranging in age from 24 to 87 years, and were assessed using the ASA grading system between grades I and III. The patients were divided into 2 groups based on the presence or absence of liver function abnormalities on the first day after surgery: a normal liver function group (NLA group) and an abnormal liver function group (LA group). Patients with elevation in any of the following indicators were included in the LA group: alanine aminotransferase >40U/L, glutamine aminotransferase >40U/L, γ-glutamyltransferase >49U/L, alkaline phosphatase >135U/L, total bilirubin >17.1μmol/L, or direct bilirubin >6.8μmol/L. The clinical data of the 2 groups of patients were compared, and only the indicators with a P-value <0.15 were included in a binary logistic regression model analysis. There were 238 patients (68.6%) who developed liver function abnormalities on the first postoperative day. In comparison to the NLA group, the LA group had a significantly higher proportion of patients with esophageal hiatal hernia type II, type III, and type IV, hypotension, and high PETCO2. Furthermore, the LA group had a significantly lower proportion of patients receiving blood transfusions. The maximum length and maximum cross-sectional area of the esophageal hiatal hernia were also significantly larger in the LA group. In addition, the operation time was significantly longer in the LA group. (all P-values are <0.15). The binary logistic regression analysis revealed that prolonged operation time (OR=1.017, 95% CI: 1.007-1.028) was the only risk factor associated with postoperative liver function abnormalities. The sole risk factor for postoperative liver function abnormalities was prolonged surgical time.

Risk factors for mortality in patients with spontaneous cerebellar hemorrhage based on Mimics software analysis

To investigate the independent risk factors for short-term mortality in patients with spontaneous cerebellar hemorrhage (SCH) based on Mimics software of medical image control system. The clinical data of SCH patients treated at Shengjing Hospital of China Medical University from January, 2010 to December, 2021 was retrospectively analyzed and compared, including gender, age, underlyin g diseases, Glasgow coma scale (GCS) and blood pressure at admission, laboratory indicators, imaging data, and short-term (3 weeks after onset) survival status. The imaging examination parameters were accurately calculated using Mimics software, including hematoma volume, longest diameter, and maximum cross-sectional area of cerebellar hemorrhage. Multivariate Logistic regression analysis was used to evaluate the independent risk factors for short-term death in SCH patients. Receiver operator characteristic curve (ROC curve) was drawn to analyze the predictive value of the four significant factors on short-term mortality in SCH patients. A total of 202 patients with SCH were included, of which 42 patients (20.8%) died within 3 weeks of onset and 160 patients (79.2%) survived. Univariate analysis showed that, compared with the survival group, the death group had significantly higher blood glucose, hematoma volume, hematoma longest diameter, hematoma maximum cross-sectional area, the ratio of hematoma maximum cross-section area and the corresponding posterior cranial fossa area, while GCS score was significantly lower, the distance from hematoma edge to the cerebral aqueduct center, and the distance from hematoma edge to the edge of brainstem were significantly shorter, the differences were statistically significant. Multivariate Logistic regression analysis showed that GCS score at admission [odds ratio (OR) = 0.875, 95% confidence interval (95%CI) was 0.767-0.998], hematoma volume (OR = 1.068, 95%CI was 1.022-1.115), the longest diameter of hematoma (OR = 1.086, 95%CI was 1.049-1.124), and the ratio of hematoma maximum cross-section area and the corresponding posterior cranial fossa area (OR = 1.119, 95%CI was 1.060-1.181) were independent risk factors for short-term mortality in SCH patients (all P < 0.05). ROC curve analysis showed that the area under the ROC curve (AUC) for predicting short-term death of patients with SCH were 0.738, 0.839, 0.728 and 0.727, respectively. When the GCS score was 12 at admission, the sensitivity was 85.0% and the specificity was 57.1%. When the hematoma volume was 8.40 mL, the sensitivity was 95.2% and the specificity was 65.0%. When the longest diameter of the hematoma was 47.10 mm, the sensitivity was 57.1% and the specificity was 80.6%. When the ratio of hematoma maximum cross-section area and the corresponding posterior cranial fossa area was 0.11, the sensitivity was 88.1% and the specificity was 48.7%. GCS score < 12 on admission, hematoma volume > 8.40 mL, hematoma longest diameter > 47.10 mm, the ratio of hematoma maximum cross-section area and the corresponding posterior cranial fossa area > 0.11 suggest a higher risk of short-term mortality in SCH patients.

Application of CT radiomics in investigating the anatomical basis of chronic dacryocystitis

Objective:To explore the relevant anatomical factors in the pathogenesis of chronic dacryocystitis based on CT radiomics. Methods:A retrospective analysis was conducted on the general data and sinus CT materials of 85 patients with chronic dacryocystitis（case group） admitted to our department from December 2020 to December 2023, and 85 individuals undergoing physical examination（control group） during the same period. The differences in anatomical parameters between the two groups were compared to study the morphological characteristics of the nasolacrimal duct in patients with chronic dacryocystitis. Univariate and multivariate logistic regression analyses were used to explore the relevant anatomical factors in the pathogenesis of chronic dacryocystitis. Results:There were statistically significant differences（P<0.05） in the proportion of combined nasal septal deviation, the distance between the anterior and posterior ridges of the lacrimal fossa, the angle between the long axis of the nasolacrimal duct and the projection on the midsagittal plane, the maximum transverse diameter of the bony nasolacrimal duct, the maximum cross-sectional area of the bony nasolacrimal duct, and the thickness of the frontal process of the maxilla between the two groups. There were no statistically significant differences（P>0.05） in whether there was a combined high-position nasal septal deviation, whether there was a combined non-high-position nasal septal deviation, and whether there was a combined pneumatized middle turbinate. Multivariate analysis showed that nasal septal deviation, the distance between the anterior and posterior ridges of the lacrimal fossa, the angle between the long axis of the nasolacrimal duct and the projection on the midsagittal plane, and the maximum cross-sectional area of the bony nasolacrimal duct are independent anatomical factors affecting the pathogenesis of chronic dacryocystitis. Conclusion:Nasal septal deviation, a large distance between the anterior and posterior ridges of the lacrimal fossa, a large angle between the long axis of the nasolacrimal duct and the projection on the midsagittal plane, and a small maximum transverse diameter of the bony nasolacrimal duct are important anatomical bases for the pathogenesis of chronic dacryocystitis, providing a basis for an in-depth understanding of the disease occurrence.

Ultrasound Visualization of the Recurrent Laryngeal Nerve: A Prospective Clinical Validation Study.

This study aimed to optimize a lateral transthyroid approach by using high-resolution ultrasonography (HRUS) for recurrent laryngeal nerve (RLN) visualization. In this prospective study of 85 patients undergoing thyroidectomy, the RLN was visualized preoperatively by using a lateral transthyroid approach via HRUS. The inferior thyroid artery, thyroid nodule, and cricoid cartilage were used as landmarks. RLN visibility was graded from poor to excellent. The accuracy of the preoperative localization of the RLN was determined by intraoperative HRUS, neuromonitoring, and surgical findings. RLN visualization and localization were verified intraoperatively by ultrasound-guided stimulation via a neuromonitoring probe in eight patients with extended incisions owing to the need for neck dissection. A total of 110 RLNs were present in 85 patients, and the locations of 103 RLNs detected by preoperative ultrasound were confirmed intraoperatively, with an accuracy rate of 93.6%. All detected RLNs were well visualized at the inferior thyroid artery and thyroid nodule levels. The RLN was visible in 83.5% of cases at the cricoid cartilage level. The maximum short-axis diameter and cross-sectional area of the RLN at all three levels were significantly larger in males than in females (p < 0.05). In total, ten RLNs were bifurcated and two showed tumor invasions. These findings were confirmed intraoperatively. Effective RLN visualization can be achieved using a lateral transthyroid approach via HRUS. The precise localization, prediction of anatomic variation, and invasion of RLN provide significant advantages in the individualized treatment, surgical planning, and nerve protection of patients with thyroid lesions.

Preparation of CIP@Fe3O4 particles and their impact on the fenton reaction processing performance of single-crystal SiC

This study proposes the preparation of CIP@Fe3O4 composite magnetic particles, which maintain excellent magnetic properties while exhibiting superior Fenton reaction performance for the magnetorheological chemical polishing of single-crystal SiC. The CIP@Fe3O4 particles were prepared by coating a nanoscale layer of Fe3O4 onto micron-sized carbonyl iron powder (CIP) using the co-precipitation method. Their Fenton reaction performance and magnetic properties were characterized, and CIP@Fe3O4 was used as a solid-phase catalyst in Fenton reaction-induced etching, frictional wear, and polishing experiments on single-crystal SiC. The prepared CIP@Fe3O4 particles have a saturation magnetization of 184.3 emu/g, representing only an 8.7 % reduction compared to CIP, yet achieved a decolorization rate of 76.2 % for the methyl orange indicator (compared to only 17.2 % with CIP alone). The Fenton reaction using CIP@Fe3O4 resulted in a prominent corrosion layer on the surface of single-crystal SiC, with the oxygen atomic fraction reaching 22.15 %. The study examined material removal from SiC under Fenton reactions with different solid-phase catalysts: CIP, CIP@Fe3O4, and CIP + Fe3O4. Frictional wear results indicated that the maximum scratch cross-sectional removal area on the SiC surface under the Fenton reaction with CIP@Fe3O4 was 474.38 μm2, representing a 207.3 % increase compared to without the Fenton reaction. Additionally, Si-O compounds were identified in the debris. Polishing experiments showed that the material removal rate (MRR) with the Fenton reaction was 3295 nm/h, an increase of 220.2 % compared to without the Fenton reaction, and the surface roughness was reduced to Ra 0.895 nm, a 73.4 % reduction compared to without the Fenton reaction. This study provides additional evidence for the application of magnetorheological technology and the Fenton reaction in the polishing field of single-crystal SiC.

Application of improved urate analysis algorithm based on spectral parameters in Podagra: A prospective study

ObjectivesTo explore whether the improved urate analysis (IUA) algorithm based on spectral parameters can reduce false positives in CT gout images compared with current urate analysis (CUA) algorithm. Materials and methodsThis prospective study was performed from May 2022 to May 2023. Spectral feet CT images of suspected gout participants were reconstructed by IUA and CUA algorithm. Qualitative diagnosis of IUA and CUA images was recorded and compared with the reference standard (ultrasound + conventional CT). Artifacts on IUA and CUA images of non-gout participants were recorded and compared; the maximum cross-sectional area of the maximum tophi (SIT-max) on IUA and CUA images of participants with gout were measured and compared. ResultsThere are 65 participants (mean age, 43.9 years ± 13.1 [SD]; 65 men) with 114 feet studies in the gout group, and 33 participants (mean age, 43.4 years ± 15.0 [SD]; 30 men) with 65 feet studies in the non-gout group. For all 179 feet studies, IUA images had higher specificity (19.2–86.6 % vs. 1.3–44.3 %) and accuracy (63.1–88.8 % vs. 41.3–57.0 %) than CUA images (P < 0.001). In the non-gout group, the reduction rates of artifacts from the nail bed, skin, beam hardening, vascular structures, tendons, and total artifacts on the IUA images compared to the CUA images was 40.5 %, 48.9 %, 74.3 %, 99.2 %, 99.6 %, and 80.0 %, respectively (P < 0.001). For 82 feet studies with tophi, SIT-max was higher on CUA images than IUA images (P < 0.05). ConclusionThe improved urate analysis algorithm based on spectral parameters can reduce image artifacts and improve diagnostic efficacy.

New staging criteria predicting m-tor inhibitors treatment effect of renal angiomyolipoma in tuberous sclerosis complex patients.

We aimed to launched new staging criteria to predict mTOR inhibitors treatment effect of renal angiomyolipomas (r-AMLs) in TSC patients. 40 TSC patients with 69 r-AMLs were divided into two groups based on the efficacy of 6-month mTOR inhibitor treatment. Epidemiological data, therapeutic response, and predictive factors of enrolled patients were collected and analyzed. Age, sex, maximum diameter, maximum cross-sectional area (CSAmax), unenhanced mean CT value, enhanced mean CT value, and added value of enhanced CT of largest r-AML at baseline were assessed as potential influencing factors. Receiver operating characteristic (ROC) curve analysis and the area under the ROC curve (AUC) was used to estimate prediction power. After 6 months of mTOR inhibitor treatment, the tumor reduction rates in the two groups were 55.87% and 16.44% (P < 0.001). At the start of treatment, the maximum diameters, CSAmax, added value of enhanced CT of the target lesion in two groups were 7.70 ± 0.73cm vs. 13.18 ± 1.23cm(P = 0.028), 57.40 ± 10.76cm2 vs. 167.29 ± 33.09cm2 (P = 0.015), and 62.32 ± 5.03HU vs. 33.06 ± 3.13HU (P = 0.009), respectively. AUCs of CSAmax, added value of enhanced CT, and combination of both were 0.8024, 0.7672, and 0.8116, respectively (P < 0.001). Cut-off values of CSAmax combined with the added value of enhanced CT were 40cm2 and 46HU. AUCs of maximum diameters, combination of maximum diameters and added value of enhanced CT were 0.7600 and 0.8100, respectively (P < 0.001), with cut-off values of 6.6cm and 46 HU. New staging criteria, based on CSAmax and added value of enhanced CT, can predict the treatment efficiency of m-TOR inhibitors for r-AMLs in TSC patients. A simplified version based on maximum diameter and added value of enhanced CT of lesion has also been proposed.

Can the Newer Model of Breast-Specific Positron Emission Tomography Reduce the "Blind Area"?

Objectives: Breast-specific positron emission tomography (PET) provides higher sensitivity and spatial resolution than whole-body PET/CT, but it has a blind area. Mammary glands near the chest wall sometimes present outside the field of view (FOV). A newer, dedicated breast PET (dbPET) model has a cylindrical detector with a larger diameter than previous models, so it is expected to eliminate or reduce blind areas. This study aimed to compare breast images acquired on the new dbPET model with images acquired on an older dbPET model to evaluate blind area reduction. Methods: The nipple-to-chest wall distance (mm), maximum breast cross-sectional area at the FOV edge (cm2) on the dbPET transverse images of the scanners, and the effects of patient age and body mass index (BMI) were compared. Results: There was no significant difference in the nipple-to-chest wall distance between the models (p = 0.223). The maximum breast cross-sectional area at the FOV edge was significantly larger on the newer model's images (p < 0.001). There was no significant correlation between breast size and the rate of change in both parameters. Conclusions: The new ring-type dbPET scanners with larger diameter detectors did not reduce the blind area observed on older dbPET scanners.

Application of small animal ultrasound imaging technology for identification of polycystic ovary syndrome in a mouse model

Background and AimsPolycystic ovary syndrome (PCOS) is a hormonal disorder common among women of reproductive age, characterized by irregular menstrual periods, elevated levels of androgens, and polycystic ovaries, leading to various symptoms and complications such as infertility, metabolic issues, and increased risk of diabetes and heart disease. This study aimed to compare traditional histological methods and ultrasound imaging for consistency in identifying PCOS in a mouse model. The shortest time to construct the PCOS model using letrozole was determined. MethodsFemale C57/BL mice were randomly divided into three groups: Group A received normal saline and a regular diet; Group B received 1 mg/kg/day of letrozole with a regular diet; and Group C received 1 mg/kg/day of letrozole with a high-fat diet. All mice were administered letrozole by intragastric gavage daily for five weeks. The traditional identification method included measuring body weight, examining vaginal smears, monitoring the estrous cycle, measuring serum androgen levels, and performing H&E staining of ovarian tissues. The PCOS model was evaluated using ultrasound imaging to identify and monitor follicles. The significance of the difference between the traditional identification method and the ultrasonic method was calculated using the nonparametric McNemar test, and consistency between the two methods was assessed with the kappa-coefficient test. On this basis, the ultrasound imaging technology was used to monitor the model-making process for 2, 3 and 4 weeks, and to monitor the parameters of the ovary and follicles to judge the shortest time that gavage letrozole caused the appearance of vesicular follicles in the mouse ovary. ResultsThe traditional identification method showed no PCOS phenotype in group A mice, while groups B and C showed multiple ovarian cystic follicles, indicating successful model induction. The ultrasound imaging results were consistent with the traditional method, showing no PCOS in group A and multiple cystic follicles in groups B and C. The McNemar test revealed no significant difference between the traditional and ultrasonic identification methods. The kappa-coefficient test assessed consistency, yielding a value of 0.903, indicating strong agreement between the methods. The ovarian area, diameter, and the number and diameter of cystic follicles were not significantly changed at two weeks in the letrozole group compared with the control group. At three weeks, there were significant increases in the number and in the diameter of vesicular follicles compared with control cells. At four weeks, the number and diameter, the maximum cross-sectional area and diameter of the ovary were significantly increased compared with the control group. ConclusionsThe ultrasound and traditional methods provide consistent results for identifying PCOS in a mouse model. Construction of the PCOS model by letrozole gavage takes at least three weeks.

Orientation optimization of the Halbach PMG for the levitation and guidance performance of the HTS maglev system

High-temperature superconducting maglev technology has great application potential in rail transit applications due to its advantages such as passive stable levitation and green environmental protection. As one of the key components of the HTS maglev system, the Halbach-type permanent magnet guideway (PMG) enhances the magnetic field on one side of the guideway and weakens that on the other side. Optimizing the PMG, including the geometry and magnetic properties of the magnet, is an effective method to improve the levitation and guidance performance of the system. In addition, since NdFeB permanent magnets are expensive, optimizing the design of the PMG for the HTS maglev system is also an important work to reduce the application cost. In this paper, the Nelder–Mead Simplex method (NMS) in the optimization solver in COMSOL software is used to optimize the geometric parameters of the Halbach PMG according to the different objective requirements of the HTS maglev system. The optimization objectives include the maximum levitation force and guidance force under the constraint of the maximum cross-sectional area of the PMG, as well as the minimum cross-sectional area of the PMG with a minimum levitation force constraint. The results indicate that the NMS method is effective. By comparing four PMGs during the optimization process, it is found that this method can fully improve the utilization of the magnetic field by changing the geometric parameters of the Halbach PMG. This study can provide a valuable reference for the optimal design of the PMG for HTS maglev systems in the future.

Quantitative parameters of HRCT target scan to predict the risk of lung adenocarcinoma based on the detection of lung ground-glass nodules.

To explore the value of high-resolution computed tomography (HRCT) in the differential diagnosis of benign and malignant ground-glass nodules (GGNs), and to provide a theoretical basis for the clinical application of HRCT. A total of 208 patients with GGN who had been clinically confirmed by surgical pathology and clinical confirmation were collected, and HRCT target scanning technology was used to scan and collect general information of patients, and observe the distribution of GGN, GGN size, GGN cross-sectional area, diameter, transverse diameter, solid composition, relationship with bronchi, and relationship with blood vessels and other indicators. Multivariate regression analysis and risk factor prediction are performed. The differences were statistically significant in multivariate regression analysis, such as nodule location, maximum diameter, maximum cross-sectional area, GGN status, nodule boundary and relationship with blood vessels (P < 0.05). The results of ROC curve showed that the AUC value of nodule site and nodule boundary was greater than 0.5, and the nodule boundary AUC value was 0.676, which was more sensitive to predict whether GGN deteriorated to lung adenocarcinoma (LUAD). Nodule site and nodule boundary are effective risk predictors for LUAD in patients with GGN, and nodule boundary is the most valuable independent predictor.

Combinations of Clinical Factors, CT Signs, and Radiomics for Differentiating High-Density Areas after Mechanical Thrombectomy in Patients with Acute Ischemic Stroke.

Clinically, hemorrhagic transformation (HT) after mechanical thrombectomy (MT) is a common complication. This study aimed to investigate the value of clinical factors, CT signs, and radiomics in the differential diagnosis of high-density areas (HDAs) in the brain after MT in patients with acute ischemic stroke with large-vessel occlusion (AIS-LVO). A total of 156 eligible patients with AIS-LVO in Center I from December 2015 to June 2023 were retrospectively enrolled and randomly divided into training (n = 109) and internal validation (n = 47) sets at a ratio of 7:3. The data of 63 patients in Center II were collected as an external validation set. According to the diagnostic criteria, the patients in the 3 data sets were divided into an HT group and a non-HT group. The clinical and imaging data from Centers I and II were used to construct a clinical factor and CT-sign model, a radiomics model, and a combined model by logistic regression. Receiver operating characteristic analysis was used to evaluate the diagnostic efficacy of each model in the 3 data sets. Clinical blood glucose and the maximum cross-sectional area on CT were associated with the HT or non-HT of the HDA according to multivariate logistic regression analyses (P < .05). Among the 3 models, the combined model had the highest diagnostic efficiency, with area under the curve values of 0.895, 0.882, and 0.820 in the 3 data sets, which were significantly greater than the area under the curve values of the radiomics model (0.887, 0.898, 0.798) and clinical factor and CT-sign model (0.831, 0.744, 0.684). The combined model based on radiomics had the best performance, indicating that radiomics features can be used as imaging biomarkers to aid in the clinical judgment of the nature of HDA after MT.

PMEL is a predictive biomarker for mTORC1 inhibitor treatment of renal angiomyolipoma in tuberous sclerosis complex patients

BackgroundWe aimed to demonstrate the function of premelanosome protein (PMEL) as a biomarker to predict the effectiveness of mammalian target of rapamycin complex 1 (mTORC1) inhibitor treatment in renal angiomyolipomas (RAMLs) in tuberous sclerosis complex (TSC) patients. Methods95 whole blood samples from 49 patients diagnosed with TSC-RAMLs were collected. PMEL, N4BP2, and PCSK1N expression in the plasma samples were tested by quantitative sandwich ELISA. The target tumor volume assessed by maximum cross-sectional area (CSAmax) in CT scans. Correlation analysis was used to determine the relationship between PMEL expression and target tumors, as well as the tumor reduction rate. ResultsThe tumor size of TSC-RAMLs positivity correlated with PMEL expression (r = 0.30, p = 0.036) and PCSK1N expression (r = 0.23, p = 0.027), but had no significant relationship with N4BP2 (r = 0.06, p = 0.89). The positive correlation between TSC-RAML tumor volume and PMEL expression still existed in TSC patients before (r = 0.30, p = 0.026) and after mTORC1 inhibitor treatment (r = 0.41, p = 0.0017), but the correlation between tumor volume and PCSK1N expression no longer existed. Further analysis found that PMEL expression negatively correlated with the reduction rate of TSC-RAMLs after mTORC1 inhibitor treatment (r = −0.50, p = 0.0022), both after 3 months (r = −0.47, p = 0.048) and 6 months of treatment (r = −0.52, p = 0.028). ConclusionPMEL expression positively correlated with the tumor size of TSC-RAMLs, and inversely with the reduction rate of TSC-RAMLs after mTORC1 inhibitor treatment, which may suggest that PMEL may serve as a predictive biomarker for the efficacy of mTORC1 inhibitor treatment.

Computed tomography-derived normative values and z-scores of the pulmonary valve annulus and sino-tubular junction in the pediatric population

BackgroundAccurate assessment of the pulmonary valve can dictate clinical management of patients with right ventricular outflow tract (RVOT) anomalies. Comparisons with available normal reference values are essential for accurate evaluation. The aim of the study was to generate normative data for the pulmonary valve annulus and sino-tubular (ST) junction using CT measurements derived from a heterogeneous pediatric population and create z-scores useful for clinical practice. MethodsPatients without heart disease who underwent cardiac CT between April 2014 and February 2021 ​at Children's Hospital Colorado were included. Minimum and maximum diameter (mm) and cross-sectional area (mm2) for the pulmonary valve annulus and ST junction were measured. Previously validated models were used to normalize the measurements and calculate z-scores. Each measurement was plotted against BSA, and z-score distributions were used as reference lines. ResultsThree-hundred-sixty-seven healthy patients with a mean age of 8.8 years (1–21), 56% male, and BSA of 1.1 ​m2 (0.4–2.1) were analyzed. The Haycock formula was used to present data as predicted values for a given BSA and within equations relating each measurement to BSA. Predicted values and z-score boundaries for all measurements are graphically re-presented. ConclusionsCT-derived normative data for the pulmonary valve annulus and ST junction is reported from a heterogenous cohort of healthy children.

A new magnetic resonance imaging-based PUMCH classification system for congenital cervical malformations: devising a standardised diagnosis pathway

ObjectivesTo develop an innovative magnetic resonance imaging (MRI)-based PUMCH (Peking Union Medical College Hospital) classification system aimed at standardising the diagnosis of congenital cervical malformations (CCMs) by identifying their distinctive MRI features.MethodsSeventy-nine consecutive patients with CCM underwent pre-treatment pelvic MRI; three experienced gynaecological radiologists retrospectively analysed these images. Qualitative assessments included Rock et al’s classification; PUMCH classification; haematometra; cervical signal features; ovarian endometriosis; haematosalpinx; and uterine, vaginal, urinary, and musculoskeletal malformations. Quantitative assessments involved the uterine volume, sagittal cervical length, and maximum ovarian cross-sectional area. The surgical treatment types were also recorded. Statistical methods were used to incorporate differences in clinical features and surgical methods into our classification.ResultsMorphologically, CCMs were categorised into three types: type I (53%) was characterised by the presence of a cervix with visible cervical canals; type II (23%) featured an existing cervix with concealed cervical canals; and type III (24%) indicated cervical aplasia, which involves a blind end in the lower part of the uterine corpus. Haematometra was significantly more prevalent in patients with type I CCM than in those with type II (p < 0.001). There were three cervical signal patterns: no signal (27%), no evident layer differentiation (21%), and multi-layer differentiation with haematocele (52%). Most patients (94%) had complete vaginal atresia. Type I CCM patients had a higher likelihood of regaining normal uterovaginal anatomy compared to types II and III.ConclusionsOur proposed PUMCH classification system has a high potential for enhancing the efficiency of clinical diagnosis among patients with CCM.Critical relevance statementThe proposed new PUMCH classification promised to elevate the conventional diagnostic trajectory for congenital cervical malformations, offering a valuable framework to refine the selection and planning of surgical interventions, thereby enhancing overall clinical efficacy.Key PointsEffective classification of congenital cervical malformations is desirable to optimise the diagnostic process.We presented a PUMCH classification of congenital cervical malformations using pelvic MRI.The new classification significantly aids clinical triage for congenital cervical malformations.Graphical

Estimate of the hydraulic force in the aging heart: a cardiovascular magnetic resonance imaging study

BackgroundCoupling between left ventricle (LV) and left atrium (LA) plays a central role in the process of cardiac remodeling during aging and development of cardiac disease. The hydraulic force (HyF) is related to variation in size between LV and LA. The objectives of this study were to: (1) derive an estimate of left atrioventricular HyF using cine- Magnetic Resonance Imaging (MRI) in healthy subjects with a wide age range, and (2) study its relationship with age and conventional diastolic function parameters, as estimated by reference echocardiography.MethodsWe studied 119 healthy volunteers (mean age 44 ± 17 years, 58 women) who underwent Doppler echocardiography and MRI on the same day. Conventional transmitral flow early (E) and late (A) LV filling peak velocities as well as mitral annulus diastolic longitudinal peak velocity (E’) were derived from echocardiography. MRI cine SSFP images in longitudinal two and four chamber views were acquired, and analyzed using feature tracking (FT) software. In addition to conventional LV and LA strain measurements, FT-derived LV and LA contours were further used to calculate chamber cross-sectional areas. HyF was approximated as the difference between the LV and LA maximal cross-sectional areas in the diastasis phase corresponding to the lowest LV-LA pressure gradient. Univariate and multivariate analyses while adjusting for appropriate variables were used to study the associations between HyF and age as well as diastolic function and strain indices.ResultsHyF decreased significantly with age (R²=0.34, p < 0.0001). In addition, HyF was significantly associated with conventional indices of diastolic function and LA strain: E/A: R²=0.24, p < 0.0001; E’: R²=0.24, p < 0.0001; E/E’: R²=0.12, p = 0.0004; LA conduit longitudinal strain: R²=0.27, p < 0.0001. In multivariate analysis, associations with E/A (R2 = 0.39, p = 0.03) and LA conduit strain (R2 = 0.37, p = 0.02) remained significant after adjustment for age, sex, and body mass index.ConclusionsHyF, estimated using FT contours, which are primarily used to quantify LV/LA strain on standard cardiac cine MRI, varied significantly with age in association with subclinical changes in ventricular filling. Its usefulness in cohorts of patients with left heart disease to detect LV-LA uncoupling remains to be evaluated.