Dichorionic triamniotic triplets after two blastocysts transfer underwent multifetal pregnancy reduction: two case reports and literature review.

BACKGROUND: The increase in the rate of multiple pregnancies in clinical practice is associated with assisted reproductive technology (ART). Given the high risk of dichorionic triamniotic (DCTA) triplet pregnancies, reducing DCTA triplet pregnancies to twin or singleton pregnancies is often beneficial. CASE PRESENTATION: This article reports on two cases of DCTA triplet pregnancies resulting from two blastocyst transfers. Given the high risk of complications such as twin-to-twin transfusion syndrome (TTTS) in monochorionic diamniotic (MCDA) twin pregnancies, patients have a strong desire to preserve the dichorionic diamniotic (DCDA) twins. Multifetal pregnancy reduction (MFPR) was performed in both cases to continue the pregnancy with DCDA twins by reducing one of the MCDA twins. Both of the pregnant women in this report eventually gave birth to healthy twins at 37 weeks. CONCLUSIONS: For infertile couples with multiple pregnancies but with a strong desire to remain the DCDA twins, our report suggests that reducing DCTA triplets to DCDA twin pregnancies may be an option based on clinical operability and assessment of surgical difficulty.

Quantification of morpho-hemodynamic changes in unruptured intracranial aneurysms with irregular pulsation during the cardiac cycle using 4D-CTA.

Background and purpose: Previous studies predicting the rupture risk of intracranial aneurysms (IAs) have predominantly utilized static imaging data, overlooking the dynamic blood flow and biomechanical properties of the aneurysm wall. Irregular pulsation detected by 4D-CTA is a potential predictor of aneurysm rupture, albeit with uncertain clinical significance. This study aimed to analyze the changes in morpho-hemodynamic characteristics of IAs during the cardiac cycle to elucidate the dynamic changes and the associated hemodynamic mechanisms. Methods: A retrospective review was conducted on the 4D-CTA data of IA patients between January 2017 and September 2019. R-R intervals were segmented into 20-time phases, reconstructing 20 CT datasets to identify irregular pulsation and extract 3D aneurysm models. Computational fluid dynamics (CFD) simulations analyzed hemodynamic parameters such as oscillatory shear index (OSI) and relative residence time (RRT). Changes in morpho-hemodynamic characteristics were quantified in terms of the absolute change (parameter*) and relative change rate (parameter%). Rupture risk was assessed using the rupture resemblance model (RRS). Results: Eleven UIAs from 10 patients were finally included, with five aneurysms showing irregular pulsation (45.45%). No significant differences in morpho-hemodynamic characteristics were observed between aneurysms with or without irregular pulsation. More remarkable changes in aneurysm size (size*: 0.59 ± 0.14 mm vs. 0.32 ± 0.12 mm, p = 0.010; size%: 10.49% ± 1.43% vs. 3.95% ± 1.79%, p < 0.001), volume (volume%: 13.72% vs. 6.39%, p = 0.009), OSI (OSI*: 0.02 ± 0.01 vs. 0.004 ± 0.005, p = 0.004; OSI%: 200% vs. 12.50%, p = 0.004) and RRT (RRT%: 97.14% vs. 43.95, p = 0.052) over the cardiac cycle were significantly linked to irregular pulsation. Aneurysms with irregular pulsation demonstrated a more unfavorable hemodynamic environment during the cardiac cycle, irrespective of the predicted rupture risk. Furthermore, irregular pulsation at the aneurysm dome exhibited higher hemodynamic instability than at the sidewall. Conclusion: Irregular pulsation may indicate hemodynamic instability within the aneurysm, leading to an increased rupture risk in the area where irregular pulsation occurs. This proof-of-concept study could enhance understanding of dynamic changes in UIAs during the cardiac cycle and the underlying hemodynamic mechanisms.

Thyroid Arteriovenous Malformation in Hereditary Hemorrhagic Telangiectasia: Insights on Successful Noninvasive Imaging.

Hereditary hemorrhagic telangiectasia (HHT) causes arteriovenous malformations (AVMs) in several organs. This report is the first to document and image a thyroid AVM complication in HHT. A 72-year-old woman with HHT was referred for thyroid nodule evaluation. Ultrasonography showed a hypervascularized nodule in the right thyroid lobe which was initially suspected to be malignant. However, 3-dimensional computed tomography angiography demonstrated a thyroid AVM with abnormal anastomosis of the superior thyroid artery and the inferior thyroid vein. In the formation of thyroid AVM, here, chronic thyroiditis and hypothyroidism complications may have been a second hit, due to the predisposing first-hit germline mutation. This report sheds light on overlooked thyroid lesions in HHT and advocates a noninvasive imaging approach in diagnosing thyroid AVMs. Furthermore, this case suggests a potential mechanism of AVM formation in human HHT, possibly supporting the second-hit hypothesis.

Quantifying irregular pulsation of intracranial aneurysms using 4D-CTA.

Recent studies have suggested that irregular pulsation of intracranial aneurysm during the cardiac cycle may be potentially associated with aneurysm rupture risk. However, there is a lack of quantification method for irregular pulsations. This study aims to quantify irregular pulsations by the displacement and strain distribution of the intracranial aneurysm surface during the cardiac cycle using four-dimensional CT angiographic image data. Four-dimensional CT angiography was performed in 8 patients. The image data of a cardiac cycle was divided into approximately 20 phases, and irregular pulsations were detected in four intracranial aneurysms by visual observation, and then the displacement and strain of the intracranial aneurysm was quantified using coherent point drift and finite element method. The displacement and strain were compared between aneurysms with irregular and normal pulsations in two different ways (total and stepwise). The stepwise first principal strain was significantly higher in aneurysms with irregular than normal pulsations (0.20±0.01 vs 0.16±0.02, p=0.033). It was found that the irregular pulsations in intracranial aneurysms usually occur during the consecutive ascending or descending phase of volume changes during the cardiac cycle. In addition, no statistically significant difference was found in the aneurysm volume changes over the cardiac cycle between the two groups. Our method can successfully quantify the displacement and strain changes in the intracranial aneurysm during the cardiac cycle, which may be proven to be a useful tool to quantify intracranial aneurysm deformability and aid in aneurysm rupture risk assessment.

Application of Synthetic Time-Of-Flight Magnetic Resonance Angiography-Computed Tomography Fusion Imaging in Preoperative Planning for Aneurysm Clipping Surgery: A Comparative Study with Three-Dimensional Computed Tomography Angiography.

OBJECTIVE: Some patients with intracranial aneurysms (IAs) cannot undergo three-dimensional computed tomography angiography (3D-CTA) or digital subtraction angiography due to contraindications to contrast agents or radiation. Time-of-flight magnetic resonance angiography (TOF-MRA) offers a contrast-free alternative but lacks cranial bone detail critical for surgical planning. This study evaluates the feasibility of using 3D Slicer to fuse TOF-MRA with thin-section CT images to generate synthetic images resembling CTA for surgical clipping planning. METHODS: This prospective study included 22 patients with unruptured IAs and 8 with ruptured IAs undergoing aneurysm clipping surgery (≥3 mm). TOF-MRA and CT/3D-CTA scans were fused using 3D Slicer. Neuroradiologists and neurosurgeons independently assessed 3D-CTA and synthetic TOF-MRA-CT images for aneurysm detection rates, morphology, and dimensions. Evaluation metrics included dice similarity coefficient and 95% Hausdorff distance. RESULTS: Evaluation of aneurysm detection rates, morphology, and dimensions showed no significant differences between synthetic TOF-MRA-CT fusion images and 3D-CTA (all P > 0.05). Neuroradiologist assessments revealed strong concordance in aneurysm morphology between synthetic TOF-MRA-CT fusion images and 3D-CTA (κ = 0.867, P < 0.001). The dice similarity coefficient (0.937 ± 0.012) and Hausdorff distance (4.54 ± 0.26) indicated a high degree of image overlap between synthetic TOF-MRA-CT fusion images and 3D-CTA. Surgeons rated the consistency of aneurysm morphology between synthetic TOF-MRA-CT fusion images and intraoperative findings as strongly concordant (κ = 0.873, P < 0.001). CONCLUSIONS: Synthetic TOF-MRA-CT fusion images closely match 3D-CTA for ≥3 mm aneurysms, demonstrating comparable diagnostic and surgical clipping planning effectiveness. They represent a promising alternative for personalized preoperative planning, particularly when contrast agents are contraindicated.

Relationships between irregular pulsation and variations in morphological characteristics during the cardiac cycle in unruptured intracranial aneurysms by 4D-CTA.

Background and purpose: Irregular pulsation of the aneurysmal wall has been suggested as a novel predictor for aneurysm rupture. Aneurysm volume variations during the cardiac cycle and the association between irregular pulsation and morphological features have been discussed, but the clinical significance remains unclear. The purpose of this study was to quantify changes in morphological characteristics over the cardiac cycle and examine their correlation with irregular pulsation to facilitate comprehension of aneurysm dynamics. Materials and methods: Fourteen unruptured intracranial aneurysms (UIAs) from 11 patients were included in this study, and each of them underwent 4D-CTA after diagnosis by DSA. The R-R intervals were divided into 20-time phases at 5% intervals to determine whether an aneurysm had irregular pulsation throughout the cardiac cycle. CT images from the 20-time phases were used to reconstruct 3D aneurysm models, measure 14 morphological parameters, and quantify each parameter's absolute change and relative rates of change during the cardiac cycle. Results: Seven of 14 UIAs exhibited irregular pulsation over the cardiac cycle by 4D-CTA, 5 of which were small aneurysms (< 7 mm). The UIAs with irregular pulsation exhibited greater changes in morphological characteristics. As aneurysm size increased, the absolute change in aneurysm volume increased (p = 0.035), but the relative rates of change in aneurysm size (p = 0.013), height (p = 0.014), width (p = 0.008), height-to-width ratio (p = 0.009), dome-to-neck ratio (p = 0.019) and bottleneck factor (p = 0.012) decreased. Conclusion: Although the larger the aneurysm, the greater the amplitude of its volumetric variation, small aneurysms are prone to irregular pulsation during the cardiac cycle and have more pronounced and dramatic morphological changes during the cardiac cycle that may increase the risk of rupture. This proof-of-concept study could help to explain the importance of dynamic changes using 4D-CTA in assessing the rupture risk of UIAs.

Pregnancy and obstetric outcomes of dichorionic triamniotic triplet pregnancies with selective foetal reduction after assisted reproductive technology.

BACKGROUND: It is generally beneficial and recommended that dichorionic triamniotic (DCTA) triplet pregnancies be reduced to monochorionic (MC) twin or singleton pregnancies after assisted reproductive technology (ART). However, some infertile couples still have a firm desire to retain twins. For this reason, the best foetal reduction strategies need to be available for infertile couples and clinicians. Given that data on the elective reduction of DCTA triplet pregnancies to twin pregnancies are scarce, we investigated the outcomes of elective reduction of DCTA triplet pregnancies through the retrospective analysis of previous data. METHOD: Patients with DCTA triplet pregnancies who underwent elective foetal reduction between January 2012 and June 2020 were recruited. A total of 67 eligible patients with DCTA triplet pregnancies were divided into two groups: a DCTA-to-dichorionic diamniotic (DCDA) twin group (n = 38) and a DCTA-to-monochorionic diamniotic (MCDA) twin group (n = 29); the basic clinical data of the two groups were collected for comparison. RESULTS: Compared with the DCDA-to-MCDA twin group, the DCTA-to-DCDA twin group had lower rates of complete miscarriage (7.89% versus 31.03%, p = 0.014), early complete miscarriage (5.26% versus 24.14%, p = 0.034), late preterm birth (25.71% versus 65.00%, p = 0.009) and very low birth weight (0 versus 11.11%, p = 0.025). In addition, the DCTA-to-DCDA twin group had higher rates of full-term delivery (65.71% versus 25.00%, p = 0.005), survival (92.11% versus 68.97%, p = 0.023), and taking the babies home (92.11% versus 68.97%, p = 0.023) than did the DCTA-to-MCDA twin group. In terms of neonatal outcomes, a significantly greater gestational age (38.06 ± 2.39 versus 36.28 ± 2.30, p = 0.009), average birth weight (3020.77 ± 497.33 versus 2401.39 ± 570.48, p < 0.001), weight of twins (2746.47 ± 339.64 versus 2251.56 ± 391.26, p < 0.001), weight of the larger neonate (2832.94 ± 320.58 versus 2376.25 ± 349.95, p < 0.001) and weight of the smaller neonate (2660.00 ± 345.34 versus 2126.88 ± 400.93, p < 0.001) was observed in the DCTA-to-DCDA twin group compared to the DCTA-to-MCDA twin group. CONCLUSION: The DCTA-to-DCDA twin group had better pregnancy and neonatal outcomes than the DCTA-to-MCDA twin group. This reduction approach may be beneficial for patients with dichorionic triamniotic triplet pregnancies who have a strong desire to have DCDA twins.

Regulation of Aerobic Succinate Transporter dctA of E. coli by cAMP-CRP, DcuS-DcuR, and EIIAGlc: Succinate as a Carbon Substrate and Signaling Molecule.

INTRODUCTION: C4-dicarboxylates (C4-DC) have emerged as significant growth substrates and signaling molecules for various Enterobacteriaceae during their colonization of mammalian hosts. Particularly noteworthy is the essential role of fumarate respiration during colonization of pathogenic bacteria. To investigate the regulation of aerobic C4-DC metabolism, the study explored the transcriptional control of the main aerobic C4-DC transporter, dctA, under different carbohydrate conditions. In addition, mutants related to carbon catabolite repression (CCR) and C4-DC regulation (DcuS-DcuR) were examined to better understand the regulatory integration of aerobic C4-DC metabolism into CCR. For initial insight into posttranslational regulation, the interaction between the aerobic C4-DC transporter DctA and EIIAGlc from the glucose-specific phosphotransferase system was investigated. METHODS: The expression of dctA was characterized in the presence of various carbohydrates and regulatory mutants affecting CCR. This was accomplished by fusing the dctA promoter (PdctA) to the lacZ reporter gene. Additionally, the interaction between DctA and EIIAGlc of the glucose-specific phosphotransferase system was examined in vivo using a bacterial two-hybrid system. RESULTS: The dctA promoter region contains a class I cAMP-CRP-binding site at position -81.5 and a DcuR-binding site at position -105.5. DcuR, the response regulator of the C4-DC-activated DcuS-DcuR two-component system, and cAMP-CRP stimulate dctA expression. The expression of dctA is subject to the influence of various carbohydrates via cAMP-CRP, which differently modulate cAMP levels. Here we show that EIIAGlc of the glucose-specific phosphotransferase system strongly interacts with DctA, potentially resulting in the exclusion of C4-DCs when preferred carbon substrates, such as sugars, are present. In contrast to the classical inducer exclusion known for lactose permease LacY, inhibition of C4-DC uptake into the cytoplasm affects only its role as a substrate, but not as an inducer since DcuS detects C4-DCs in the periplasmic space ("substrate exclusion"). The work shows an interplay between cAMP-CRP and the DcuS-DcuR regulatory system for the regulation of dctA at both transcriptional and posttranslational levels. CONCLUSION: The study highlights a hierarchical interplay between global (cAMP-CRP) and specific (DcuS-DcuR) regulation of dctA at the transcriptional and posttranslational levels. The integration of global and specific transcriptional regulation of dctA, along with the influence of EIIAGlc on DctA, fine-tunes C4-DC catabolism in response to the availability of other preferred carbon sources. It attributes DctA a central role in the control of aerobic C4-DC catabolism and suggests a new role to EIIAGlc on transporters (control of substrate uptake by substrate exclusion).

Value of Head and Neck 4D-CTA Combined with SDF-1a/CXCR4 Signaling Pathway in Assessing the Risk of Ruptured Intracranial Posterior Communicating Aneurysms / 昆明医科大学学报

Objective To investigate the value of 4D-CTA combined with SDF-1a/CXCR4 signaling pathway in evaluating the risk of intracranial aneurysm rupture.Methods Fifty patients with unruptured intracranial posterior communicating aneurysms and 50 patients with ruptured intracranial posterior communicating aneurysms were divided into unruptured group 1 and ruptured group 1.All patients underwent 4D-CTA examination and serumSDF-1alevel was detected.Non-ruptured group 1 was followed up for 12 months(After conservative treatment),on this basis,patients with ruptured posterior communicating aneurysms were included in ruptured group 2,and patients with unruptured posterior communicating aneurysms were included in non-ruptured group 2.Results The AUC values of Wn,AR,L,SR,SDF-1a and their combinations in diagnosing ruptured intracranial posterior communicating aneurysms were all greater than 0.70.The AUC values of Wn,AR,L,SR,SDF-1a and their combinations in predicting ruptured intracranial posterior communicating aneurysms in ruptured group 2 were all greater than 0.70.Conclusion 4D-CTA combined with SDF-1acan effectively distinguish ruptured intracranial posterior communicating aneurysms and predict the risk of rupture.

Constrained estimation of intracranial aneurysm surface deformation using 4D-CTA.

BACKGROUND AND OBJECTIVE: Intracranial aneurysms are relatively common life-threatening diseases, and assessing aneurysm rupture risk and identifying the associated risk factors is essential. Parameters such as the Oscillatory Shear Index, Pressure Loss Coefficient, and Wall Shear Stress are reliable indicators of intracranial aneurysm development and rupture risk, but aneurysm surface irregular pulsation has also received attention in aneurysm rupture risk assessment. METHODS: The present paper proposed a new approach to estimate aneurysm surface deformation. This method transforms the estimation of aneurysm surface deformation into a constrained optimization problem, which minimizes the error between the displacement estimated by the model and the sparse data point displacements from the four-dimensional CT angiography (4D-CTA) imaging data. RESULTS: The effect of the number of sparse data points on the results has been discussed in both simulation and experimental results, and it shows that the proposed method can accurately estimate the surface deformation of intracranial aneurysms when using sufficient sparse data points. CONCLUSIONS: Due to a potential association between aneurysm rupture and surface irregular pulsation, the estimation of aneurysm surface deformation is needed. This paper proposed a method based on 4D-CTA imaging data, offering a novel solution for the estimation of intracranial aneurysm surface deformation.

Correlation between the rate of morphological changes and rupture of intracranial aneurysms during one cardiac cycle analyzed by 4D-CTA.

Objective: This study aimed to analyze the relationship between the rate of morphological changes and intracranial aneurysm rupture during the cardiac cycle. Methods: Eighty-four patients with intracranial aneurysms were retrospectively analyzed and divided into the rupture (42 cases) and unruptured (42 cases) groups. Four-dimensional computed tomography angiography (4D-CTA) was performed to collect quantitative parameters of aneurysm morphology and calculate the morphological change rate. The potential factors associated with aneurysm rupture were determined by comparing the general clinical data and rate of change in the location and morphology of the aneurysm between the two groups. Results: Each morphological change rate in the rupture group was generally higher than that of the unruptured group. The rate of dome height change and aneurysm volume change were independent factors associated with aneurysm rupture. ROC curve analysis revealed that the diagnostic accuracy of the aneurysm volume change rate was higher. When the volume change rate was 12.33%, the sensitivity and specificity of rupture were 90.5 and 55.8%, respectively. Conclusion: The rate of change in dome height and volume of intracranial aneurysms during one cardiac cycle were independent factors associated with aneurysm rupture.

Dynamic evaluation of unruptured intracranial aneurysms by 4D-CT angiography: comparison with digital subtraction angiography (DSA) and surgical findings.

BACKGROUND: This study was to prospectively investigate the feasibility of four-dimensional computed tomography angiography (4D-CTA) with electrocardiogram-gated (ECG) reconstruction for preoperative evaluation of morphological parameters, and compared with digital subtraction angiography (DSA). We also aimed to detect pulsation in unruptured intracranial aneurysms (UIAs) by using 4D-CTA, as a potential predicting factor of growth or rupture. MATERIALS: 64 patients with 64 UIAs underwent ECG-gated dynamic 4D-CTA imaging before treatment, of which 46 patients additionally underwent DSA. Original scanning data were reconstructed to produce 20 data sets of cardiac cycles with 5%-time intervals. The extent of agreement on UIAs morphological features assessed with 4D-CTA and DSA was estimated using the k coefficient of the Kappa test. The radiation doses were also calculated and compared between 4D-CTA and DSA. In the aneurysmal surgically treated in our institution, we were able to compare the surgical findings of the aneurysm wall with 4D-CTA images. We performed long-term follow-up on untreated patients. RESULTS: The morphological characteristics detected by 4D-CTA and DSA were consistent in aneurysm location (k = 1.0), shape (k = 0.76), maximum diameter (k = 0.94), aneurysm neck (k = 0.79) and proximity to parent and branch vessels (k = 0.85). 4D-CTA required lower radiation doses (0.32 ± 0.11 mSv) than DSA (0.84 ± 0.37 mSv, P < 0.001). Pulsation was detected in 26 of the 64 unruptured aneurysms, and all underwent neurosurgical clipping or interventional embolization. In aneurysms surgically treated in our hospital, we observed a significant correlation between 4D-CTA findings and surgical evaluation of the aneurysmal wall, in particular the irregular pulsations detected on 4D-CTA have demonstrated to correspond to dark-reddish thinner wall at surgery. CONCLUSIONS: In this proof-of-concept study, 4D-CTA provided real-time, non-invasive preoperative assessments of UIAs comparable to DSA. Moreover, optimal correlation between the irregular pulsation detected by 4D-CTA and the surgical findings support a possible role of this technique to identify aneurysms with a higher risk of rupture.

[Evaluation of the Usefulness of Variable-speed Injection Method in Neck to Lower-extremity Three-dimensional Computed Tomography Angiography].

PURPOSE: The purpose of this study was to investigate the contrast effect of arteries and the distribution of contrast medium along the z-axis in three-dimensional computed tomography angiography from neck to lower extremity (neck-lower-extremity 3D-CTA) using the F variable-speed injection method. METHOD: The subjects were 112 patients who underwent neck-lower-extremity 3D-CTA. In the fixed-speed injection method, contrast medium was injected at the same rate for 35 s. In the variable-speed injection method, contrast medium was injected for 35 s at varying rates. CT values were measured in the common carotid artery (CCA), ascending aorta (AAo), abdominal aorta (AA), superficial femoral artery (SFA), popliteal artery (PA), anterior tibial artery (ATA), and dorsalis pedis artery (DPA). We normalized the CT values of each artery for each patient, defined the contrast uniformity, and compared them. We also performed a four-level visual evaluation. RESULT: A significant difference was found in the PA, ATA, and DPA, with the variable-speed injection method showing a higher CT value than the fixed-speed injection method (p<0.01). There were no significant differences in the CCA, AAo, AA, and SFA. Similarly, the variable-speed injection method scored significantly higher in the visual evaluation. CONCLUSION: The variable-speed injection method is useful in neck-lower-extremity 3D-CTA.

Vagus Nerve Visualization Using Fused Images of 3D-CT Angiography and MRI as Preoperative Evaluation for Vagus Nerve Stimulation.

Vagus nerve stimulation (VNS) is an effective surgical option for intractable epilepsy. Although the surgical procedure is not so complicated, vagus nerve detection is sometimes difficult due to its anatomical variations, which may lead to surgical manipulation-associated complications. Thus, this study aimed to visualize the vagus nerve location preoperatively by fused images of three-dimensional computed tomography angiography (3D-CTA) and magnetic resonance imaging (MRI). This technique was applied to two cases. The neck 3D-CTA and MRI were performed, and the fused images were generated using the software. The vagus nerve and its anatomical relationship with the internal jugular vein (IJV) and common carotid artery were clearly visualized. The authors predicted that the vagus nerve was detected by laterally pulling the IJV according to the images. Intraoperatively, the vagus nerve was located as the authors predicted. The time of the surgery until the vagus nerve detection was <60 min in both cases. This novel radiological technique for visualizing the vagus nerve is effective to quickly detect the vagus nerve, which has anatomical variations, during the VNS.

Fumarate, a central electron acceptor for Enterobacteriaceae beyond fumarate respiration and energy conservation.

C4-dicarboxylates (C4-DCs) such as fumarate, l-malate and l-aspartate are key substrates for Enterobacteria such as Escherichia coli or Salmonella typhimurium during anaerobic growth. In general, C4-DCs are oxidants during biosynthesis, e.g., of pyrimidine or heme, acceptors for redox balancing, a high-quality nitrogen source (l-aspartate) and electron acceptor for fumarate respiration. Fumarate reduction is required for efficient colonization of the murine intestine, even though the colon contains only small amounts of C4-DCs. However, fumarate can be produced endogenously by central metabolism, allowing autonomous production of an electron acceptor for biosynthesis and redox balancing. Bacteria possess a complex set of transporters for the uptake (DctA), antiport (DcuA, DcuB, TtdT) and excretion (DcuC) of C4-DCs. DctA and DcuB exert regulatory functions and link transport to metabolic control through interaction with regulatory proteins. The sensor kinase DcuS of the C4-DC two-component system DcuS-DcuR forms complexes with DctA (aerobic) or DcuB (anaerobic), representing the functional state of the sensor. Moreover, EIIAGlc from the glucose phospho-transferase system binds to DctA and presumably inhibits C4-DC uptake. Overall, the function of fumarate as an oxidant in biosynthesis and redox balancing explains the pivotal role of fumarate reductase for intestinal colonization, while the role of fumarate in energy conservation (fumarate respiration) is of minor importance.

Detection of Intracranial Aneurysms Using Multiphase CT Angiography with a Deep Learning Model.

RATIONALE AND OBJECTIVES: Determine the effect of a multiphase fusion deep-learning model with automatic phase selection in detection of intracranial aneurysm (IA) from computed tomography angiography (CTA) images. MATERIALS AND METHODS: CTA images of intracranial arteries from patients at Ningbo First Hospital were retrospectively analyzed. Images were randomly classified as training data, internal validation data, or test data. CTA images from cases examined by digital subtraction angiography (DSA) were examined for independent validation. A deep-learning model was constructed by automatic phase selection of multiphase fusion, and compared to the single-phase algorithm to evaluate algorithm sensitivity. RESULTS: We analyzed 1110 patients (1493 aneurysms) as training data, 139 patients (174 aneurysms) as internal validation data, and 134 patients (175 aneurysms) as test data. The sensitivity of the multiphase analysis of the internal validation data, test data, and independent validation data were greater than from the single-phase analysis. The recall of the multiphase selection was greater or equal to that of single-phase selection in the aneurysm position, shape, size, and rupture status. Use of the test data to determine the presence and absence of aneurysm rupture led to a recall from multiphase selection of 94.8% and 87.6% respectively; both of these values were greater than those from single-phase selection (89.6% and 79.4%). CONCLUSION: A multiphase fusion deep learning model with automatic phase selection provided automated detection of IAs with high sensitivity.

Correlation of 4D-CTA Imaging and Rupture Risk of Anterior Communicating Aneurysms / 昆明医科大学学报

Objective To explore the correlation between 4D-CTA imaging and the risk factors for the rupture of anterior communicating aneurysms.Methods A total of 100 patients with anterior communicating aneurysms in the Department of Radiology of Yan'an Hospital of Kunming City from June 2020 to March 2023 were selected as the study objects.The patients were divided into ruptured group and unruptured group based on whether the aneurysm had ruptured(with 50 cases in each group).The unruptured group(50 cases)received conservative treatment and follow-up observation for 1-12 months.The measurements included the aneurysm neck width(Wn),aneurysm height(H),average diameter of the carrying artery(DA),aneurysm length(L),aneurysm neck ratio(AR),the ratio of aneurysm height to carrying artery diameter(SR),aneurysm volume to aneurysm base area(VOR),and the search for the pulsation point of the aneurysm,analyzing the correlation between these measurements and aneurysm rupture.Results Wn,AR,L and SR in ruptured group 1 were higher than those in non-ruptured group 1(P<0.05).Wn,AR,L and SR in fracture group 2 were higher than those in non-fracture group 2(P<0.05).The CT values of internal carotid artery and middle cerebral artery,and the CT values and noise of brain parenchyma in 4D-CTA were higher than those in 3D-CTA(P<0.05).Conclusion The use of 4D-CTA imaging for quantitative analysis of anterior communicating aneurysms can not only predict the risk of rupture,but also provide better image quality compared to 3D imaging while reducing radiation dosage.4D-CTA imaging has a positive impact on the diagnosis and treatment of clinical aneurysms.

Significant Slowed Cortical Venous Blood Flow in Patients with Acute Ischemic Stroke with Large Vessel Occlusion Suggests Poor Collateral Circulation and Prognosis.

RATIONALE AND OBJECTIVES: To investigate the change of cortical venous flow in acute ischemic stroke patients with large vessel occlusion (LVO-AIS) and its clinical value. MATERIALS AND METHODS: Baseline whole-brain 4D-CTA/CTP and clinical data of LVO-AIS and a control group were collected from June 2020 to October 2021. Venous inflow time (VIT), venous peak time (VPT), and venous outflow time (VOT) were analyzed on both sides of patients and normal controls. The VIT/VPT/VOT were statistically described and compared between the patient group and normal controls, then, in patients with different collateral circulation and prognoses. Next, the correlation between cortical venous drainage time and collateral circulation grading was analyzed. Finally, logistic regression analysis was used to explore the relationship between the three venous times and prognosis, and receiver operating characteristic (ROC) curves were plotted to assess the value of delayed cortical venous imaging in predicting prognosis. RESULTS: 149 LVO-AIS and 73 normal controls were collected. VIT, VPT, and VOT were significantly delayed on the affected side in the patient group compared with the healthy side (p<0.05) and the controls (p<0.05); VIT and VPT were also significantly delayed on the healthy side of patients compared with the controls (p<0.05). Delayed VIT and VPT on the affected side in the patient group were more significant in patients with poor collateral circulation (p<0.05), and VIT and VPT on the affected side in the patient group were negatively correlated with arterial collateral scores. VIT and VPT were significantly delayed in both sides of patients in the poor prognosis group compared with the good prognosis group (p<0.05). logistic regression showed that patients' affected VPT, arterial collateral scores, and NIHSS were independent predictors of poor prognosis, with an accuracy of 79.6% in predicting poor prognosis. The affected VPT and NIHSS were independent predictors of poor prognosis for patients presenting within 24 hours, with an accuracy of 79.6% in predicting poor prognosis. CONCLUSION: Cortical venous flow was significantly slowed in both sides of LVO-AIS patients. delayed ipsilateral VPT in LVO-AIS patients can be used as an imaging indicator to determine poor collateral circulation and predict poor prognosis.

Fetoscopic laser surgery for twin-to-twin transfusion syndrome in DCTA triplets compared to MCDA twins: collaborative study and literature review.

OBJECTIVE: To compare the outcomes of dichorionic triamniotic (DCTA) triplets with that of monochorionic diamniotic (MCDA) twin gestations undergoing fetoscopic laser surgery (FLS) for treatment of twin-to-twin transfusion syndrome (TTTS). METHODS: Retrospective cohort study of prospectively collected data of consecutive DCTA triplet and MCDA twin pregnancies with TTTS that underwent FLS at two fetal treatment centers between 2012 and 2020. Preoperative, operative and, postoperative variables were collected. Perinatal outcomes were investigated. Primary outcome was survival to birth and to neonatal period. Secondary outcomes were gestational age (GA) at birth and procedure-to-delivery interval. Literature review was conducted in which PubMed, Web of Science, and Scopus were searched from inception to September, 2020. RESULTS: Twenty four sets of DCTA triplets were compared to MCDA twins during the study period. There were no significant differences in survival (no survivor, single, or double survivors) to birth and to the neonatal period of the MC twin pairs of the DCTA triplets vs MCDA twins. Median GA at delivery was approximately three weeks earlier in DCTA triplets compared to MCDA twins (28.4 weeks vs 31.4 weeks, p = .035, respectively). Rates of preterm birth (PTB) less than 32 and less than 28 weeks were significantly higher in DCTA triplets compared to twins (<32 weeks: 70.8% vs 51.1%, p = .037, respectively, and <28 weeks: 37.5% vs 20.8%, p = .033, respectively). CONCLUSION: Perinatal survival including fetal and neonatal are comparable between DCTA triplets and MCDA twins. However, this might have resulted from the small sample size of the DCTA triplets. GA at delivery is earlier in triplets, which could be due to the nature of triplet gestation rather than to the laser procedure itself.

Image level detection of large vessel occlusion on 4D-CTA perfusion data using deep learning in acute stroke.

OBJECTIVES: Automated image-level detection of large vessel occlusions (LVO) could expedite patient triage for mechanical thrombectomy. A few studies have previously attempted LVO detection using artificial intelligence (AI) on CT angiography (CTA) images. To our knowledge this is the first study to detect LVO existence and location on raw 4D-CTA/ CT perfusion (CTP) images using neural network (NN) models. MATERIALS AND METHODS: Retrospective study using data from a level-I stroke center was performed. A total of 306 (187 with LVO, and 119 without) patients were evaluated. Image pre-processing included co-registration, normalization and skull stripping. Five consecutive time-points for each patient were selected to provide variable contrast density in data. Additional data augmentation included rotation and horizonal image flipping. Our model architecture consisted of two neural networks, first for classification (based on hemispheric asymmetry), followed by second model for exact site of LVO detection. Only cases deemed positive by the classification model were routed to the detection model, thereby reducing false positives and improving specificity. The results were compared with expert annotated LVO detection. RESULTS: Using a 80:20 split for training and validation, the combination of both classification and detection model achieved a sensitivity of 86.5%, a specificity of 89.5%, and an accuracy of 87.5%. A 5-fold cross-validation using the entire data achieved a mean sensitivity of 82.7%, a specificity of 89.8%, and an accuracy of 85.5% and a mean AUC of 0.89 (95% CI: 0.85-0.93). CONCLUSION: Our findings suggest that accurate image-level LVO detection is feasible on CTP raw images.