The rupture risk of intracranial saccular aneurysm: a case-control study based on a three-dimensional computed tomography angiography model

Background

Assessing the risk of rupture in intracranial aneurysms is crucial. Advancements in medical imaging now allow for three-dimensional (3D) assessments of aneurysms, providing a more detailed understanding of their morphology and associated risks. This study aimed to compare the 3D morphological parameters of ruptured and unruptured intracranial saccular aneurysms (ISAs) using computed tomography angiography (CTA) and to analyze risk factors linked to ISA rupture.

Methods

This retrospective case-control study included patients diagnosed with ISAs via CTA, for which data were sourced from both the Emergency Department and Inpatient Unit in The First Affiliated Hospital of Jinan University. The patients were categorized into rupture and unrupture groups. We used 3D-Slicer (version 5.2.2, Slicer Community) to construct morphological models of the ISAs and their parent arteries. These models facilitated assessments of intracranial aneurysmal volume (IAV), aneurysmal surface area (ASA), and maximum sectional area (MSA). Differences in 3D morphological parameters between ruptured and unruptured ISAs were then analyzed. For statistical analysis, we first performed single factor analysis on the data, constructed a receiver operating characteristic (ROC) curve one by one with statistically significant parameters, and screened out ROC curves that met the sample requirements. Second, we performed multiparameter logistic regression analysis to construct a ROC curve model and analyzed its predictive performance.

Results

The analysis encompassed 97 patients comprising 97 ISAs diagnosed from March 2016 to March 2022. Significant differences in morphological parameters were observed between the rupture and unrupture groups (P<0.05), including IAV, ASA, MSA, IAV/diameter (IAV/D), IAV/neck width (IAV/N), MSA/diameter (MSA/D), MSA/neck width (MSA/N), ASA/neck width (ASA/N), and ASA/MSA. It was found that the IAV, ASA, and MSA values of the rupture group were larger than those of the unrupture group. Meanwhile, the IAV/D, IAV/N, MSA/D, MSA/N, and ASA/N values were larger in the rupture group, while ASA/MSA and ASA/IAV were smaller.

Conclusions

This study underscores the significance of specific morphological indicators, such as ASA/N and ASA/MSA, in predicting the rupture risk of ISAs. The IAV, MSA, and ASA parameters, especially in relation to diameter and neck width, provide crucial insights into the rupture potential of ISAs.

Sonographic Features of Uterine Arteriovenous Malformation: A Case Series

Uterine arteriovenous malformation (AVM) is very rare but potentially life-threatening. Early and accurate diagnosis is the cornerstone of its management. The objective of this study is to encourage sonographers to become familiar with a variety of grayscale sonographic features, facilitating rapid recognition of the patterns and prompting them to apply color flow Doppler for a diagnosis of uterine AVM and possible further investigations or interventions. We present six cases of uterine AVM presenting with abnormal uterine bleeding at varying degrees of severity, from abnormal menstruation to life-threatening bleeding following curettage. All initially provided some clues of uterine AVM upon grayscale ultrasound, leading to the application of color Doppler flow to support a diagnosis, with confirmation using abdominal computer tomography angiography (CTA) in most cases, resulting in definitive treatment using uterine artery embolization or other interventions. Most importantly, this study provides various sonographic features of uterine AVM, such as appearances of small tubular structures, spongy patterns, a conceptive-product-like appearance, and spaghetti-like patterns. Hopefully, familiarity with these sonographic features can facilitate practitioners to make an early diagnosis, leading to proper further investigation and intervention, and to prevent serious complications from potentially being caused by this subtle but very serious disorder.

FL% is associated with the severity of acute DeBakey type I aortic dissection in patients undergoing frozen elephant trunk and total arch replacement

Objectives

The diameter, area, and volume of the true lumen and false lumen (FL) have been measured in previous studies to evaluate the extent of DeBakey type I aortic dissection. However, these indicators have limitations because of the irregular shapes of the true and false lumens and the constant oscillation of intimal flap during systole and diastole. The ratio of arch lengths seems to be a more reliable indicator. FL% was defined as the ratio of the arch length of FL to the circumference of the aorta at the different levels of the aorta. The purpose of this article was to investigate whether FL% is a predictor of the severity of acute DeBakey type I aortic dissection in patients undergoing frozen elephant trunk (FET) and total arch replacement.

Methods

In this retrospective observational study, we analyzed a total of 344 patients with acute DeBakey type I aortic dissection that underwent FET and total arch replacement at our center from October 2015 to October 2019. The patients were divided into two groups by cluster analysis according to the perioperative course. Binary logistic regression analyses were performed to determine whether FL% could predict the severity of acute DeBakey type I aortic dissection. The area under the receiver operating characteristic curve (AUROC) was used to assess the power of the multivariate logistic regression model for the severity of acute DeBakey type I aortic dissection.

Results

The patients in the ultra-high-risk group (109 patients) had significantly more severe clinical comorbidities and complications than the patients in the high-risk group (235 patients). The ascending aortic FL% [odds ratio (OR), 11.929 (95% CI: 1.421-100.11); P = 0.022], location of initial tear [OR, 0.68 (95% CI: 0.47-0.98); P = 0.041], the degree of left iliac artery involvement [OR, 1.95 (95% CI: 1.15-3.30); P = 0.013], and the degree of right coronary artery involvement [OR, 1.46 (95% CI: 1.01-2.12); P = 0.045] on preoperative computed tomography angiography were associated with the severity of acute DeBakey type I aortic dissection. The AUROC value of this multivariate logistic regression analysis was 0.940 (95% CI: 0.914-0.967; P < 0.001). The AUROC value of ascending aortic FL% was 0.841 (95% CI: 0.798-0.884; P < 0.001) for the severity of acute DeBakey type I aortic dissection in patients undergoing FET and total arch replacement.

Conclusions

Ascending aortic FL% was validated as an essential radiologic index for assessing the severity of acute DeBakey type I aortic dissection in patients undergoing FET and total arch replacement. Higher values of ascending aortic FL% were more severe.

Compare deep learning model and conventional logistic regression model for the identification of unstable saccular intracranial aneurysms in computed tomography angiography

Background

It is crucial to distinguish unstable from stable intracranial aneurysms (IAs) as early as possible to derive optimal clinical decision-making for further treatment or follow-up. The aim of this study was to investigate the value of a deep learning model (DLM) in identifying unstable IAs from computed tomography angiography (CTA) images and to compare its discriminatory ability with that of a conventional logistic regression model (LRM).

Methods

From August 2011 to May 2021, a total of 1,049 patients with 681 unstable IAs and 556 stable IAs were retrospectively analyzed. IAs were randomly divided into training (64%), internal validation (16%), and test sets (20%). Convolutional neural network (CNN) analysis and conventional logistic regression (LR) were used to predict which IAs were unstable. The area under the curve (AUC), sensitivity, specificity and accuracy were calculated to evaluate the discriminating ability of the models. One hundred and ninety-seven patients with 229 IAs from Banan Hospital were used for external validation sets.

Results

The conventional LRM showed 11 unstable risk factors, including clinical and IA characteristics. The LRM had an AUC of 0.963 [95% confidence interval (CI): 0.941-0.986], a sensitivity, specificity and accuracy on the external validation set of 0.922, 0.906, and 0.913, respectively, in predicting unstable IAs. In predicting unstable IAs, the DLM had an AUC of 0.771 (95% CI: 0.582-0.960), a sensitivity, specificity and accuracy on the external validation set of 0.694, 0.929, and 0.782, respectively.

Conclusions

The CNN-based DLM applied to CTA images did not outperform the conventional LRM in predicting unstable IAs. The patient clinical and IA morphological parameters remain critical factors for ensuring IA stability. Further studies are needed to enhance the diagnostic accuracy.

Application of deep learning image reconstruction-high algorithm in one-stop coronary and carotid-cerebrovascular CT angiography with low radiation and contrast doses

Background

For patients with suspected simultaneous coronary and cerebrovascular atherosclerosis, conventional single-site computed tomography angiography (CTA) for both sites can result in nonnegligible radiation and contrast agent dose. The purpose of this study was to validate the feasibility of one-stop coronary and carotid-cerebrovascular CTA (C&CC-CTA) with a "double-low" (low radiation and contrast) dose protocol reconstructed with deep learning image reconstruction with high setting (DLIR-H) algorithm.

Methods

From February 2018 to January 2019, 60 patients referred to C&CC-CTA simultaneously in West China Hospital were recruited in this prospective cohort study. By random assignment, patients were divided into two groups: double-low dose group (n=30) used 80 kVp and 24 mgI/kg/s contrast dose with images reconstructed using DLIR-H; and routine-dose group (n=30) used 100 kVp and 32 mgI/kg/s contrast dose with images reconstructed using 50% adaptive statistical iterative reconstruction-V (ASIR-V50%). Radiation and contrast doses, subjective image quality score, CT attenuation values, noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured and compared between the groups.

Results

The DLIR-H group used 30% less contrast dose (35.80±4.85 vs. 51.13±6.91 mL) and 48% less overall radiation dose (1.00±0.09 vs. 1.91±0.42 mSv) than the ASIR-V50% group (both P<0.001). There was no statistically significant difference on subjective quality score between the two groups (C-CTA: 4.38±0.67 vs. 4.17±0.81, P=0.337 and CC-CTA: 4.18±0.87 vs. 4.08±0.79, P=0.604). For coronary CTA, lower background noise (18.93±1.43 vs. 22.86±3.75 HU) was reached in DLIR-H group, and SNR and CNR at all assessed branches were significantly increased compared to ASIR-V50% group (all P<0.05), except SNR of left anterior descending (P>0.05). For carotid-cerebrovascular CTA, DLIR-H group was comparable in background noise (19.25±1.42 vs. 20.23±2.40 HU), SNR and CNR at all assessed branches with ASIR-V50% group (all P>0.05).

Conclusions

The "double-low" dose one-stop C&CC-CTA with DLIR-H obtained higher image quality compared with the routine-dose protocol with ASIR-V50% while achieving 48% and 30% reduction in radiation and contrast dose, respectively.

Feasibility of using 8 mL of iodinated contrast media in cerebral computed tomographic angiography with a dual-layer spectral detector

Background

Virtual monoenergetic images (VMIs) at a low energy level can improve image quality when the amount of iodinated contrast media (CM) is reduced. The purpose was to evaluate the feasibility of using an extremely low CM volume and injection rate in cerebral computed tomography angiography (CTA) on a dual-layer spectral detector computed tomography (CT).

Methods

Patients who were clinically suspected of intracranial aneurysm or cerebrovascular diseases were included in our study (from June to November 2022). In this prospective study, 80 patients were randomly enrolled into group A (8 mL of CM with a 1-mL/s flow rate) or group B (40 mL of CM with 4-mL/s flow rate). The VMIs at 40-70 keV in group A and polychromatic conventional images in the 2 groups were reconstructed. CT attenuation, image noise, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR) were evaluated via the t-test or Mann-Whitney test (2 groups), while analysis of variance or Kruskal-Wallis test (multiple groups). Subjective image quality was assessed on a 5-point scale.

Results

In group A, the subjective image quality score, CT attenuation, and CNR of the internal carotid artery (ICA) and middle cerebral artery (MCA) were the highest on VMIs at 40 keV. The image noise on VMIs at 40 keV was 5.08±0.84 Hounsfield units. The subjective image quality score, CT value of the ICA, MCA, and cerebral parenchyma on VMIs at 40 keV in group A were similar to those in group B (all P values >0.05). Compared to those in group B, the VMIs at 40 keV in group A demonstrated a significantly higher mean SNR and CNR of the ICA (mean SNR: 46.22±20.18 vs. 34.32±12.40, P=0.002; CNR: 55.47±13.43 vs. 46.18±12.30, P=0.002) and MCA [SNR: 13.66 (9.78, 20.29) vs. 9.99 (7.53, 14.00), P=0.003; CNR: 47.00±12.71 vs. 39.45±10.47, P=0.005].

Conclusions

Cerebral CTA on VMIs at 40 keV with 8 mL of CM and a 1-mL/s injection rate can provide diagnostic image quality.

Midterm follow-up after computed tomography angiography planned left atrial appendage closure

BACKGROUND

While studies have shown the advantages of computed tomography angiography (CTA) over transesophageal echocardiography (TEE) in left atrial appendage closure (LAAC) preprocedural planning for WATCHMAN™ legacy and FLX devices, there has been no reported long-term data for this approach.

OBJECTIVES

We sought to evaluate long-term outcomes using CTA-based preprocedural planning for LAAC using the WATCHMAN™ device.

METHODS

A prospective analysis of 231 consecutive patients who underwent LAAC in a single, large academic hospital in the United States was conducted over a 5-year period. CTA-guided preprocedural planning was performed in all. Procedural success, adverse events, length of procedure, number of devices used, and length of stay were evaluated. Rates of death, cerebral embolism, systemic embolism, and major and minor bleeding were recorded. Adjusted predicted stroke and major bleeding rates were derived from CHA2DS2-Vasc and HAS-BLED scores, respectively.

RESULTS

From January 26, 2017, to November 23, 2021, 231 patients underwent LAAC with CTA preprocedural planning by two operating physicians. The mean age of patients was 76.5 ± 8.4. 59.7% of patients were male. Mean CHA2DS2VASc and HAS-BLED scores were 4.5 ± 1.4 and 3.9 ± 0.9, respectively. All procedures were performed with intracardiac echo (100%). The procedural success rate was 99.1%. The CTA sizing strategy accurately predicted the implant size in 93.5% of patients. Mean number of devices used was 1.10 ± 0.3. Peri-procedural complication rate was 2.2%. 6 patients were lost to follow-up. Mean follow-up was 608.94 days with a total of 377.04 patient years. Median follow-up period of 368 days (interquartile range: 209-1067 days). There were 51 deaths from all causes (13.52 per 100 patient-years), 10 cases of cerebral embolism (2.65 per 100 patient-years), 2 cases of systemic embolism (0.53 per 100 patient-years), 17 cases of major bleeding (4.50 per 100 patient-years), and 31 cases of minor bleeding (8.2 per 100 patient-years). All-cause mortality at 1, 2, and 3 years was 12.7%, 20.9%, and 29.2%, respectively. CV event rates at 1, 2, and 3 years were 2.1%, 6.6%, and 10.5%, respectively.

CONCLUSIONS

CTA-based preprocedural planning is accurate in predicting device size for LAAC and associated with excellent clinical outcomes at 5 years.

Pericarotid adipose tissue computed tomography attenuation distinguishes different stages of carotid atherosclerotic disease: a cross-sectional study

Background

Carotid atherosclerotic plaque inflammation plays a critical role in guiding the prevention of secondary stroke. Increased perivascular adipose tissue attenuation observed on computed tomography angiography (CTA) may indicate local inflammation. Our objective was to investigate whether pericarotid adipose tissue (PCAT), as a local inflammation biomarker, could distinguish between different stages of carotid atherosclerotic disease plaques.

Methods

We prospectively enrolled 45 consecutive acute stroke patients with carotid artery stenosis from September 2019 to September 2021. We then matched them to non-stroke patients (n=67) and no carotid atherosclerotic disease controls (n=65) based on gender, age, and cardiovascular risk factors. We compared PCAT attenuation, carotid plaque features on CTA, clinical risk factors, and serum inflammatory factors across the different groups. To detect the association of PCAT attenuation with stage of carotid atherosclerotic disease, we used multivariable logistic regression analysis.

Results

Patients with acute stroke had a higher PCAT attenuation (-78.80±11.62 HU) than patients with non-stroke (-89.01±10.81 HU, P<0.001) and no carotid atherosclerotic disease controls (-95.24±10.81 HU, P<0.001). PCAT attenuation was significantly increased in non-stroke patients compared to non-stroke patients over no carotid atherosclerotic disease controls (P=0.004). The association between PCAT attenuation and the stage of carotid atherosclerotic disease was independent of age, gender, cardiovascular risk factors, and CTA plaque characteristics. No interaction was observed between clinical features and CTA plaque characteristics on PCAT attenuation.

Conclusions

PCAT attenuation, which is an imaging biomarker of local inflammation, independently distinguishes patients with different stages of carotid atherosclerotic disease. Quantitative evaluation of PCAT attenuation in carotid atherosclerotic disease is expected to guide targeted surgical treatment of carotid plaque.

Computed tomography angiography-based radiomics model to identify high-risk carotid plaques

Background

Extracranial atherosclerosis is one of the major causes of stroke. Carotid computed tomography angiography (CTA) is a widely used imaging modality that allows detailed assessments of plaque characteristics. This study aimed to develop and test radiomics models of carotid plaques and perivascular adipose tissue (PVAT) to distinguish symptomatic from asymptomatic plaques and compare the diagnostic value between radiomics models and traditional CTA model.

Methods

A total of 144 patients with carotid plaques were divided into symptomatic and asymptomatic groups. The traditional CTA model was built by the traditional radiological features of carotid plaques measured on CTA images which were screened by univariate analysis and multivariable logistic regression. We extracted and screened radiomics features from carotid plaques and PVAT. Then, a support vector machine was used for building plaque and PVAT radiomics models, as well as a combined model using traditional CTA features and radiomics features. The diagnostic value between radiomics models and traditional CTA model was compared in identifying symptomatic carotid plaques by Delong method.

Results

The area under curve (AUC) values of traditional CTA model were 0.624 and 0.624 for the training and validation groups, respectively. The plaque radiomics model and PVAT radiomics model achieved AUC values of 0.766, 0.740 and 0.759, 0.618 in the two groups, respectively. Meanwhile, the combined model of plaque and PVAT radiomics features and traditional CTA features had AUC values of 0.883 and 0.840 for the training and validation groups, respectively, and the receiver operating characteristic curves of combined model were significantly better than those of traditional CTA model in the training group (P<0.001) and validation group (P=0.029).

Conclusions

The combined model of the radiomics features of carotid plaques and PVAT and the traditional CTA features significantly contributes to identifying high-risk carotid plaques compared with traditional CTA model.

Machine learning prediction model for the rupture status of middle cerebral artery aneurysm in patients with hypertension: a Chinese multicenter study

Background

Hypertension is a common comorbidity in patients with unruptured intracranial aneurysms and is closely associated with the rupture of aneurysms. However, only a few studies have focused on the rupture risk of aneurysms comorbid with hypertension. This retrospective study aimed to construct prediction models for the rupture of middle cerebral artery (MCA) aneurysm associated with hypertension using machine learning (ML) algorithms, and the constructed models were externally validated with multicenter datasets.

Methods

We included 322 MCA aneurysm patients comorbid with hypertension who were being treated in four hospitals. All participants underwent computed tomography angiography (CTA), and aneurysm morphological features were measured. Clinical characteristics included sex, age, smoking, and hypertension history. Based on the clinical and morphological characteristics, the training datasets (n=277) were used to fit the ML algorithms to construct prediction models, which were externally validated with the testing datasets (n=45). The prediction performances of the models were assessed by receiver operating characteristic (ROC) curves.

Results

The areas under the ROC curve (AUCs) of the k-nearest-neighbor (KNN), neural network (NNet), support vector machine (SVM) and logistic regression (LR) models in the training datasets were 0.83 [95% confidence interval (CI): 0.78-0.88], 0.87 (95% CI: 0.82-0.92), 0.91 (95% CI: 0.88-0.95), and 0.83 (95% CI: 0.77-0.88), respectively, and in the testing datasets were 0.74 (95% CI: 0.59-0.89), 0.82 (95% CI: 0.69-0.94), 0.73 (95% CI: 0.58-0.88), and 0.76 (95% CI: 0.61-0.90), respectively. The aspect ratio (AR) was ranked as the most important variable in the ML models except for NNet. Further analysis showed that the AR had good diagnostic performance, with AUC values of 0.75 in the training datasets and 0.77 in the testing datasets.

Conclusions

The ML models performed reasonably accurately in predicting MCA aneurysm rupture comorbid with hypertension. AR was demonstrated as the leading predictor for the rupture of MCA aneurysm with hypertension.

Using computed tomography angiography and computational fluid dynamics to study aortic coarctation in different arch morphologies

Objective

To study the differences in computed tomography angiography (CTA) imaging of gothic arches, crenel arches, and romanesque arches in children with Aortic Coarctation (CoA), and to apply computational fluid dynamics (CFD) to study hemodynamic changes in CoA children with gothic arch aorta.

Methods

The case data and CTA data of children diagnosed with CoA (95 cases) in our hospital were retrospectively collected, and the morphology of the aortic arch in the children was defined as gothic arch (n = 27), crenel arch (n = 25) and romanesque arch (n = 43). The three groups were compared with D1/AOA, D2/AOA, D3/AOA, D4/AOA, D5/AOA, and AAO-DAO angle, TAO-DAO angle, and aortic arch height to width ratio (A/T). Computational fluid dynamics was applied to assess hemodynamic changes in children with gothic arches.

Results

There were no significant differences between D1/AOA and D2/AOA among gothic arch, crenel arch, and romanesque arch (P > 0.05). The differences in D3/AOA, D4/AOA, and D5/AOA among the three groups were statistically significant (P < 0.05), D4/AOA, D5/AOA of the gothic arch group were smaller than the crenel arch group, and the D3/AOA and D5/AOA of the gothic arch group were smaller than the romanesque arch group (P < 0.05). The difference in AAO-DAO angle among the three groups was statistically significant (P < 0.05), and the AAO-DAO angle of gothic arch was smaller than that of romanesque arch and crenel arch group (P < 0.05). There was no significant difference in the TAO-DAO angle between the three groups (P > 0.05). The difference in A/T values among the three groups was statistically significant (P < 0.05), and the A/T values: gothic arch > romanesque arch > crenel arch (P < 0.05). The CFD calculation of children with gothic arch showed that the pressure drop between the distal stenosis and the descending aorta was 58 mmHg, and the flow rate at the isthmus and descending aorta was high and turbulent.

Conclusion

Gothic aortic arch is common in CoA, it may put adverse effects on the development of the aortic isthmus and descending aorta, and its A/T value and AAO-DAO angle are high. CFD could assess hemodynamic changes in CoA.

Could tumour volume and major and minor axis based on CTA statistical anatomy improve the pre-operative T-stage in oesophageal cancer?

OBJECTIVES

To statistically study the 3D shape of oesophageal cancer (EC) and its spatial relationships based on computed tomography angiography (CTA) 3D reconstruction, to determine its relationship with T-stages, and to create an optimal T-stage diagnosis protocol based on CTA calculation.

METHODS

Pre-operative CTA images of 155 patients with EC were retrospectively collected and divided into four groups: T1-T4. We used Amira software to segment and 3D reconstruct the EC, oesophagus, aorta, pericardium and peripheral lymph nodes and measured their surface area, volume, major axis, minor axis, longitudinal length, roughness and relationship to the aorta of the EC. One-way ANOVA, independent sample t-test, ROC, etc., were performed and critical values between different T-stages were calculated. We also invited two radiologists to evaluate the measurements.

RESULTS

There were no significant differences in EC longitudinal length, roughness score and relationship with the aorta between the different T-stages of EC. There were significant differences in EC surface area, EC volume and mean major and minor axis among the different T-stages. The volumes of the T1-T4 tumours were 12,934.36 ± 7739.25, 23,095.27 ± 14,975.67, 37,577.98 ± 36,085.64 and 58,579.25 ± 41,073.96 mm³ separately (p < 0.05), and the T1-T4 volume cut-off values were 11,712.00, 19,809.00 and 44,103.50 mm³ separately. For comparison with radiologists, the AUC value of our measurements was 0.704, which was higher than the radiologists of AUC = 0.630.

CONCLUSIONS

EC volume, major and minor axis can be used as important factors for surgeons in the T-stage diagnosis of EC, which helps to improve prognosis and treatment decisions after CTA.

A radiomics model based on aortic computed tomography angiography: the impact on predicting the prognosis of patients with aortic intramural hematoma (IMH)

Background

The prognosis of aortic intramural hematoma (IMH) is unpredictable, but computed tomography angiography (CTA) plays an important role of high diagnostic performance in the initial diagnosis and during follow-up of patients. In this study, we investigated the value of a radiomics model based on aortic CTA for predicting the prognosis of patients with medically treated IMH.

Method

A total of 120 patients with IMH were enrolled in this study. The follow-up duration ranged from 32 to 1,346 days (median 232 days). Progression of these patients was classified as follows: destabilization, which refers to deterioration in the aortic condition, including significant increases in the thickness of the IMH, the progression of IMH to a penetrating aortic ulcer (PAU), aortic dissection (AD), or rupture; or stabilization, which refers to an unchanged appearance or a decrease in the size or disappearance of the IMH. The patients were divided into a training cohort (n=84) and a validation cohort (n=36). Six different machine learning classifiers were applied: random forest (RF), K-nearest neighbor (KNN), Gaussian Naive Bayes, decision tree, logistic regression, and support vector machine (SVM). The clinical-radiomics combined nomogram model was established by multivariate logistic regression. The area under the receiver operating characteristic (ROC) curve (AUC) was implemented to evaluate the discrimination performance of the models. The calibration curves and Hosmer-Lemeshow test were used for evaluating model calibration. DeLong's test was performed to compare the AUC performance of models.

Results

Among all of the patients, 60 patients showed destabilization and 60 patients remained stable. A total of 12 radiomic features were retained after application of the least absolute shrinkage and selection operator (LASSO). These features were used for the machine learning model construction. The SVM-radial basis function (SVM-RBF) model obtained the best performance with an AUC of 0.765 (95% CI, 0.593-0.906). In the validation cohort, the combined clinical-radiomics model [AUC =0.787; 95% confidence interval (CI), 0.619-0.923] showed a significantly higher performance than did the clinical model (AUC =0.596; 95% CI, 0.413-0.796; P=0.021) and had a similar performance to the radiomics model (AUC =0.765; 95% CI, 0.589-0.906; P=0.672).

Conclusions

A quantitative nomogram based on radiomic features of CTA images can be used to predict disease progression in patients with IMH and may help improve clinical decision-making.

Research and application of intelligent image processing technology in the auxiliary diagnosis of aortic coarctation

Objective

To explore the application of the proposed intelligent image processing method in the diagnosis of aortic coarctation computed tomography angiography (CTA) and to clarify its value in the diagnosis of aortic coarctation based on the diagnosis results.

Methods

Fifty-three children with coarctation of the aorta (CoA) and forty children without CoA were selected to constitute the study population. CTA was performed on all subjects. The minimum diameters of the ascending aorta, proximal arch, distal arch, isthmus, and descending aorta were measured using manual and intelligent methods, respectively. The Wilcoxon signed-rank test was used to analyze the differences between the two measurements. The surgical diagnosis results were used as the gold standard, and the diagnostic results obtained by the two measurement methods were compared with the gold standard to quantitatively evaluate the diagnostic results of CoA by the two measurement methods. The Kappa test was used to analyze the consistency of intelligence diagnosis results with the gold standard.

Results

Whether people have CoA or not, there was a significant difference (p < 0.05) in the measurements of the minimum diameter at most sites using the two methods. However, close final diagnoses were made using the intelligent method and the manual. Meanwhile, the intelligent measurement method obtained higher accuracy, specificity, and AUC (area under the curve) compared to manual measurement in diagnosing CoA based on Karl's classification (accuracy = 0.95, specificity = 0.9, and AUC = 0.94). Furthermore, the diagnostic results of the intelligence method applied to the three criteria agreed well with the gold standard (all kappa ≥ 0.8). The results of the comparative analysis showed that Karl's classification had the best diagnostic effect on CoA.

Conclusion

The proposed intelligent method based on image processing can be successfully applied to assist in the diagnosis of CoA.

Novel Computed Tomography Angiography-Based Sizing Methodology for WATCHMAN FLX Device in Left Atrial Appendage Closure

BACKGROUND

While there is recent data suggesting an advantage of Computed Tomography Angiography (CTA) over transesophageal echocardiography (TEE) for pre-procedural left atrial appendage closure (LAAC) planning, there is limited published experience for sizing strategies. Device sizing for LAAC may be challenging and non-invasive algorithms that improve this selection process are warranted.

OBJECTIVES

We sought to evaluate the safety and the feasibility for the implementation of a novel CTA-based sizing methodology for WATCHMAN^™ FLX device in a series of patients undergoing LAAC using the TruPlan™ software package.

METHODS

A prospective analysis of 136 consecutive patients who underwent LAAC over a 12-month period in a single, large academic hospital in the United States was conducted. CTA-guided pre-procedural planning and intracardiac echocardiography (ICE) was performed in all. Procedural success, adverse events, length of procedure, number of devices used, and length of stay were evaluated.

RESULTS

A total of 136 patients who underwent LAAC procedure with WATCHMAN^™ FLX platform between October 1, 2020 until September 30, 2021 were included. The pre-specified protocol using CTA and ICE was implemented in all patients (100%). Mean CHA₂ DS₂ VASc score was 4.4 ± 1.3 and the mean HAS-BLED score was 3.9 ± 0.8. ICE-guided 100% transseptal puncture success rate was 100% with 98.5% of overall procedural success rate. Pre-procedural CTA sizing strategy accurately predicted the implanted size in 91.1% of patients. Ten patients (7.4%) required another sized device and 2 cases were aborted. At 45-day follow-up, only 1 patient (0.7%) had significant peri-device leak (≥ 5mm) on TEE.

CONCLUSIONS

CTA-based pre-procedural sizing methodology for WATCHMAN^™ FLX in LAAC was safe, feasible and associated with excellent procedural outcomes. Further studies are warranted to confirm if the features specific to TruPlan^™ may reduce the number of deployment attempts, the number of devices utilized in the procedure, and the risk of complications. This article is protected by copyright. All rights reserved.

The Predictive Value of the Perivascular Adipose Tissue CT Fat Attenuation Index for Coronary In-stent Restenosis

Objectives

To investigate the association between the perivascular adipose tissue (PVAT) fat attenuation index (FAI) derived from coronary computed tomography angiography (CCTA) and the prevalence of in-stent restenosis (ISR) in patients with coronary stent implantation.

Methods

A total of 117 patients with previous coronary stenting referred for invasive coronary angiography (ICA) were enrolled in this retrospective observational analysis. All patients underwent CCTA between July 2016 and November 2021. The deep learning-based (DL-based) method was used to analyze and measure the peri-stent FAI value. Additionally, the relationship between hematological and biochemical parameters collected from all the patients was also explored. The least absolute shrinkage and selection operator (LASSO) method was applied to the most useful feature selection, and binary logistic regression was used to test the association between the selected features and ISR. The predictive performance for ISR of the identified subgroups was evaluated by calculating the area under the curve (AUC) of receiver operator curves plotted for each model. The Pearson correlation coefficient was used to assess the correlation of peri-stent FAI values with degrees of ISR.

Results

The peri-stent FAI values in the ISR group were significantly higher than those in the non-ISR group (−78.1 ± 6.2 HU vs. −87.2 ± 7.3 HU, p < 0.001). The predictive ISR features based on the LASSO analysis were peri-stent FAI, high-density lipoprotein cholesterol (HDL-C), apolipoprotein A1 (ApoA1), and high-sensitivity c-reactive protein (hs-CRP), with an AUC of 0.849, 0.632, 0.620, and 0.569, respectively. Binary logistic regression analysis determined that peri-stent FAI was uniquely and independently associated with ISR after adjusting for other risk factors (odds ratio [OR] 1.403; 95% CI: 1.211 to 1.625; p < 0.001). In the subgroup analysis, the AUCs of the left anterior descending coronary artery (LAD), left circumflex coronary artery (LCx), and right coronary artery (RCA) stents groups were 0.80, 0.87, and 0.96, respectively. The Pearson's correlation coefficient indicated a term moderately correlation between ISR severity and peri-stent FAI values (r = 0.579, P < 0.001).

Conclusions

The peri-stent FAI can be used as an independently non-invasive biomarker to predict ISR risk and severity after stent implantation.

Delayed multiple intracranial aneurysms caused by left atrial myxoma: a case report and literature review

Intracranial aneurysm may appear even after the removal of the cardiac myxoma. However, the pathogenesis and treatment of such aneurysm lesions are not clear. The study aimed to explore the clinical and imaging manifestation, hypothetical pathogenesis, and therapy in one case of left atrial myxoma causing multiple intracranial aneurysms. A 14-year-old male displayed a 3-hour history of episodic loss of consciousness and right hemiplegia after a leapfrog-like movement. The myxoma was diagnosed by a combination of clinical examination, leading to the diagnosis of mitral dynamic obstruction with a Grade III mitral diastolic murmur and tumor plop; magnetic resonance imaging, revealing multiple ischemic sites in both semi-oval centers; and transthoracic echocardiography, demonstrating a mitral valve obstruction. The myxoma was removed surgically; however, computed tomography angiography showed multiple intracranial aneurysms in both middle cerebral arteries 18 months after resection of the atrial myxoma. After conservative treatment, the patient had no neurological dysfunction symptoms for 5 years after myxoma resection. His condition is relatively stable. In conclusion, resection of the atrial myxoma may eliminate the early neurological symptoms, but it cannot ensure the nonoccurrence of delayed intracranial aneurysms. The neoplastic process theory was favored for explaining the aneurysm development in this case. According to the specific conditions of the patient, a combination of open surgery, chemotherapy, radiotherapy, and coil embolization is recommended.

Exploring value of CT coronary imaging combined with machine-learning methods to predict myocardial ischemia

PURPOSE

To establish a machine-learning (ML) model based on coronary computed tomography angiography (CTA) images for evaluating myocardial ischemia in patients diagnosed with coronary atherosclerosis.

METHODS

This retrospective analysis includes CTA images acquired from 110 patients. Among them, 58 have myocardial ischemia and 52 have normal myocardial blood supply. The patients are divided into training and test datasets with a ratio 7 : 3. Deep learning model-based CQK software is used to automatically segment myocardium on CTA images and extract texture features. Then, seven ML models are constructed to classify between myocardial ischemia and normal myocardial blood supply cases. Predictive performance and stability of the classifiers are determined by receiver operating characteristic curve with cross validation. The optimal ML model is then validated using an independent test dataset.

RESULTS

Accuracy and areas under ROC curves (AUC) obtained from the support vector machine with extreme gradient boosting linear method are 0.821 and 0.777, respectively, while accuracy and AUC achieved by the neural network (NN) method are 0.818 and 0.757, respectively. The naive Bayes model yields the highest sensitivity (0.942), and the random forest model yields the highest specificity (0.85). The k-nearest neighbors model yields the lowest accuracy (0.74). Additionally, NN model demonstrates the lowest relative standard deviations (0.16 for accuracy and 0.08 for AUC) indicating the high stability of this model, and its AUC applying to the independent test dataset is 0.72.

CONCLUSION

The NN model demonstrates the best performance in predicting myocardial ischemia using radiomics features computed from CTA images, which suggests that this ML model has promising potential in guiding clinical decision-making.

Association of baseline and change in global longitudinal strain by computed tomography with post-transcatheter aortic valve replacement outcomes

AIMS

Transcatheter aortic valve replacement (TAVR) procedural planning requires computed tomography angiography (CTA) which allows for the assessment of left ventricular global longitudinal strain (CTA-LVGLS). There is, however, limited data on the feasibility of CTA-LVGLS, and its prognostic value. This study sought to evaluate the incremental prognostic value of baseline CTA-LVGLS, change in CTA-LVGLS after TAVR, and their association with post-TAVR outcomes.

METHODS AND RESULTS

A total of 431 patients who underwent multiphasic gated CTA using dual-source system for TAVR planning at baseline and 1-month follow-up were included [median (interquartile range) age, 83 (77-87) years; 44% female, STS-PROM score: 3.3 (2.3-5.1)%, Echo-left ventricular ejection fraction (LVEF): 60 (55-65)%, CTA-LVGLS: -18.0 (-21.6 to -14.2)%, feasible in 97% of patients]. CTA-LVGLS was measured using dedicated feature-tracking software. Over a median follow-up of 19 (13-27) months, 99 endpoints of all-cause death or heart failure hospitalization occurred. The relative hazard of the endpoint increased as baseline CTA-LVGLS worsened with -18.2% as the threshold for higher events (P = 0.005). After adjustment for baseline characteristics, CTA-LVGLS remained associated with the endpoint [hazard ratio (HR) (95% confidence interval, CI), 1.08 (1.03-1.14); P = 0.005] and incrementally improved prognostication (C-index difference, 0.026). Although CTA-LVGLS improved after TAVR [-18.3 (-21.6 to -14.3)% vs. -18.7 (-21.9 to -15.4)%, P < 0.001], patients without CTA-LVGLS improvement had higher risk of the endpoint than those with improvement or preserved baseline global longitudinal strain [HR (95% CI), 1.92 (1.19-3.12); P = 0.008].

CONCLUSIONS

In this predominantly low-risk TAVR cohort of patients, mostly with normal LVEF, assessment of CTA-LVGLS is highly feasible improving risk stratification by providing independent and incremental prognostic value over clinical and echocardiographic characteristics.

Blood Pressure Behavior After Correction Adult Coarctation of Aorta Short Term Follows Up

Background

Coarctation of aorta (CoA) is a relatively common congenital cardiac defect often causing few symptoms and therefore can be challenging to diagnose. Usually, untreated CoA may lead to a renal, vascular and cardiac complication that starts to appear at beginning of the fourth decade of life. Several methods have been proved as a modality for the treatment of CoA like balloon dilation, stenting, and surgery, etc.

Objective

To assess the hypertensive condition after endovascular stenting adult with CoA in short term follow up.

Methods

We report the outcome in 75 patients, out of these 30 male patients (40%) and 45 female patients (60%) were involved in this prospective longitudinal study, their age range between 16 to 41 years. Stenting of simple coarctation was performed on 75 patients at the Cardiology consult department in Al-najaf cardiac center or from a private clinic between January 2018 to January 2019. For the treatment of all patients, echocardiography, CT chest done to confirm diagnosis then all undergo catheterization of aorta with two sheaths one femoral and other radial to measure pressure gradient across the stenosis and stent localization follow by stenting with pre and post-dilation if needed then measure pressure gradient across stent.

Results

Out of 75 patients 69 patients (92%) returned for the 6-month follow-up evaluation and 53 patients (70%) returns for the 1-year follow-up evaluation with stent implantation, interrupted coarctation immediately after stent pressure gradient falls in almost all our patient. The patient returns at the time of 6 months and one year follow up, the assessment was done through CT angiography. At the time of six months, 39/69 patients (52%) and at the time of 1 year 18/45 patients (24%) show no aortic wall injury or aneurysm development.

Conclusion

Uncovered stents appear to be safe in treating CoA with less morbidity and mortality. Stent adult with CoA hasthe advantage of lowering blood pressure in those suffering from hypertension.

Thoracic CTA in infants and young children: Image quality of dual-source CT (DSCT) with high-pitch spiral scan mode (turbo flash spiral mode) with or without general anesthesia with free-breathing technique

PURPOSE

To determine whether diagnostic quality thoracic computed tomography angiography (CTA) studies can be obtained without general anesthesia (GA) in infants and young children using dual-source computed tomography (DSCT) with turbo flash spiral mode (TFSM) and free-breathing technique.

MATERIALS AND METHODS

All consecutive infants and young children (≤ 6 years old) who underwent thoracic CTA studies from January 2018 to October 2020 for suspected congenital thoracic disorders were categorized into two groups: with GA (Group 1) and without GA (Group 2). All thoracic CTA studies were performed on a DSCT scanner using TFSM and free-breathing technique. Two pediatric thoracic radiologists independently evaluated motion artifact in three lung zones (upper, mid, and lower). Degree of motion artifact was graded 0-3 (0, none; 1, mild; 2, moderate; and 3, severe). Logistic models adjusted for age and gender were used to compare the degree of motion artifact between lung zones. Interobserver agreement between reviewers was evaluated with kappa statistics.

RESULTS

There were a total of 73 pediatric patients (43 males (59%) and 30 females (41%); mean age, 1.4 years; range, 0-5.9 years). Among these 73 patients, 42 patients (58%) underwent thoracic CTA studies with GA (Group 1) and the remaining 31 patients (42%) underwent thoracic CTA studies without GA (Group 2). Overall, the degree of motion artifact was higher for Group 2 (without GA). However, only a very small minority (1/31, 3%) of Group 2 (without GA) thoracic CTA studies had severe motion artifact. There was no significant difference between the two groups with respect to the presence of severe motion artifact (odds ratio [OR] = 6, p = .222). When two groups were compared with respect to the presence of motion artifact for individual lung zones, motion artifact was significantly higher in the upper lung zone for Group 2 (without GA) (OR = 20, p = .043). Interobserver agreement for motion artifact was high, the average Kappa being 0.81 for Group 1 and 0.95 for Group 2.

CONCLUSION

Although the degree of motion artifact was higher in the group without GA, only a small minority (3%) of thoracic CTA studies performed without GA had severe motion artifact, rendering the study nondiagnostic. Therefore, the results of this study support the use of thoracic CTA without GA using DSCT with TFSM and free-breathing in infants and young children. In addition, given that motion artifact was significantly higher in the upper lung zone without GA, increased stabilization in the upper chest and extremities should be considered.

[Usefulness of Trapezoidal Cross-injection in Aortic 3D-CTA]

PURPOSE

This study aimed to compare the contrast effects of administration via the subclavian vein, the superior vena cava and right ventricular venous tract, and the aorta in three-dimensional computed tomography angiography (3D-CTA) using one-step injection and trapezoidal cross-injection.

METHOD

The subjects were 56 patients who underwent aortic 3D-CTA. In the one-step injection method, a 30-second injection of contrast medium was followed by saline injected at the same rate as the 30-ml contrast medium. In the trapezoidal cross-injection method, after injecting the contrast agent for 15 seconds, a variable mixture of the contrast agent and saline was injected for 15 seconds, followed by 20 ml saline injected at the same rate as the initial contrast agent injection. CT values were measured in the subclavian vein, superior vena cava, right ventricle, and aorta.

RESULT

A significant difference was found in the subclavian vein and right ventricle, with the trapezoidal cross-injection method showing a lower CT value than the one-step injection method (p<0.01). There were no significant differences in the CT values in the superior vena cava and the aorta.

CONCLUSION

The trapezoidal cross-injection method for aortic 3D-CTA produced lower CT values in venous pathways than those via the one-step injection method, but no changes were observed in the aortic CT values. These results suggest that the trapezoidal cross-injection method is useful in aortic 3D-CTA.

Persistent fifth aortic arch: a single-center experience, case series

BACKGROUND

Persistent fifth aortic arch (PFAA) is an extremely rare congenital cardiovascular malformation and there is limited data in the literature. The objective of this study is to enhance our understanding and diagnosis of PFAA from echocardiography and computed tomography angiography (CTA) findings, and to evaluate the application of echocardiography in the diagnosis of PFAA.

METHODS

We retrospectively reviewed five cases of PFAA diagnosed from October 2016 to September 2019 at the Affiliated Children's Hospital of Capital Institute of Pediatrics. We described their diagnosis by echocardiography and CTA findings, and medical history.

RESULTS

Five cases of PFAA were identified in the study. Patients aged from 3 to 48 months and weighed from 4 to 12 kg presented different clinical symptoms upon clinical examination. All the patients completed a primary echocardiographic assessment; however, the first two patients were misdiagnosed by echocardiography and was confirmed by supplemental CTA while the other three patients were directly diagnosed by echocardiography. Surgery was necessary for three patients, two of whom accepted and one refused. The other two patients only needed a follow-up assessment, which showed good results.

CONCLUSIONS

The clinical manifestation of PFAA in our patient population was atypical, and their diagnosis depended on the use of echocardiography. In the case of uncertainty, the final diagnosis was confirmed by CTA. Although the nomenclature and embryonic origin of PFAA remains controversial, the accurate diagnosis of aortic arch abnormalities and associated malformations are imperative for time-sensitive treatments.

Automated vessel segmentation in lung CT and CTA images via deep neural networks

BACKGROUND

The distribution of pulmonary vessels in computed tomography (CT) and computed tomography angiography (CTA) images of lung is important for diagnosing disease, formulating surgical plans and pulmonary research.

PURPOSE

Based on the pulmonary vascular segmentation task of International Symposium on Image Computing and Digital Medicine 2020 challenge, this paper reviews 12 different pulmonary vascular segmentation algorithms of lung CT and CTA images and then objectively evaluates and compares their performances.

METHODS

First, we present the annotated reference dataset of lung CT and CTA images. A subset of the dataset consisting 7,307 slices for training and 3,888 slices for testing was made available for participants. Second, by analyzing the performance comparison of different convolutional neural networks from 12 different institutions for pulmonary vascular segmentation, the reasons for some defects and improvements are summarized. The models are mainly based on U-Net, Attention, GAN, and multi-scale fusion network. The performance is measured in terms of Dice coefficient, over segmentation rate and under segmentation rate. Finally, we discuss several proposed methods to improve the pulmonary vessel segmentation results using deep neural networks.

RESULTS

By comparing with the annotated ground truth from both lung CT and CTA images, most of 12 deep neural network algorithms do an admirable job in pulmonary vascular extraction and segmentation with the dice coefficients ranging from 0.70 to 0.85. The dice coefficients for the top three algorithms are about 0.80.

CONCLUSIONS

Study results show that integrating methods that consider spatial information, fuse multi-scale feature map, or have an excellent post-processing to deep neural network training and optimization process are significant for further improving the accuracy of pulmonary vascular segmentation.

Analysis of segmentation of lung parenchyma based on deep learning methods

Precise segmentation of lung parenchyma is essential for effective analysis of the lung. Due to the obvious contrast and large regional area compared to other tissues in the chest, lung tissue is less difficult to segment. Special attention to details of lung segmentation is also needed. To improve the quality and speed of segmentation of lung parenchyma based on computed tomography (CT) or computed tomography angiography (CTA) images, the 4th International Symposium on Image Computing and Digital Medicine (ISICDM 2020) provides interesting and valuable research ideas and approaches. For the work of lung parenchyma segmentation, 9 of the 12 participating teams used the U-Net network or its modified forms, and others used the methods to improve the segmentation accuracy include attention mechanism, multi-scale feature information fusion. Among them, U-Net achieves the best results including that the final dice coefficient of CT segmentation is 0.991 and the final dice coefficient of CTA segmentation is 0.984. In addition, attention U-Net and nnU-Net network also performs well. In this paper, the methods chosen by 12 teams from different research groups are evaluated and their segmentation results are analyzed for the study and references to those involved.

Renal artery dissection as an overuse Injury

The diagnosis of renal infarction is often convoluted due to its non-specific presentation. It can mimic disease processes as disparate as pyelonephritis, diverticulitis, or nephrolithiasis. This case is further complicated by the presence of a pelvic kidney with triplicate arterial input. It is difficult to estimate the incidence of pelvic kidneys as the numerous sources vary wildly in their estimations; however, the paucity information, in and of itself, speaks to the rarity of the condition. In this case, a 58-year-old male presents to the emergency department after experiencing sharp, sudden, and severe groin pain while swinging a golf club. The patient was noted to have an abnormally high systolic blood pressure in the 170s and hematuria, but all other initial labs and assessments were unremarkable. An initial computed tomography scan with intravenous contrast of the abdomen and pelvis showed partial necrosis of a pelvic kidney. Follow-up computed tomography angiography revealed that a dissection in one of the arteries supplying the kidney created an infarction and resultant necrosis. Vessel size, location and time between injury and diagnosis made endovascular intervention impractical. The patient was started on aspirin and Plavix, observed for 3 days and sent home.

Preoperative assessment of the risk of cavernous ICA injury in endoscopic transsphenoidal surgery

In endoscopic endonasal transsphenoidal procedures, ICA injury occurs in up to 3.8% [1]. The highest hazard of injury is in case of contact between the ICA and pituitary gland, during opening of the dura. Preoperative imaging, i.e. CTA, MRA, supports objectively intraoperative techniques of imaging. CTA as well as MRA are essential to access anatomic details in variability of cavernous segments of the ICA (C4 ICA). The aim of the study was to measure the space between Internal Carotid Arteries and distances between the pituitary gland and ICA on both sides. Anatomic relations between left and right ICAs were accessed on CTA (coronal scans) at levels: A - The most concave point of the C4-C5 bend; B - The most convex point of the C4 bend; C - The C4 posterior ascending portion. Distances between pituitary gland and ICAs were measured on both sides on MRA (axial scans): A' - The most concave point of C4-C5 bend; B' - The most convex point of the C4 bend. The Statistica 13 (StatSoft) software was used for the statistical analysis. The Mann-Whitney U test was applied to determine differences between the groups. To analyze the strength of correlations between the quantitative variables, Spearman's rank correlation coefficients were calculated. The results were considered statistically significant at the level of P &lt; 0.05. Distance reduction was shown between pituitary glands and cavernous segment (C4) of ICAs on both sides, which is related to age. This has impact on surgical planning and highlights the risk of intraoperative injury of ICAs.

CT imaging features of carotid artery plaque vulnerability

Despite steady advances in medical care, cardiovascular disease remains one of the main causes of death and long-term morbidity worldwide. Up to 30% of strokes are associated with the presence of carotid atherosclerotic plaques. While the degree of stenosis has long been recognized as the main guiding factor in risk stratification and therapeutical decisions, recent evidence suggests that features of unstable, or ‘vulnerable’, plaques offer better prognostication capabilities. This paradigmatic shift has motivated researchers to explore the potentialities of non-invasive diagnostic tools to image not only the lumen, but also the vascular wall and the structural characteristics of the plaque. The present review will offer a panoramic on the imaging modalities currently available to characterize carotid atherosclerotic plaques and, in particular, it will focus on the increasingly important role covered by multidetector computed tomographic angiography.

Impaired cerebral hemodynamics in late-onset depression: computed tomography angiography, computed tomography perfusion, and magnetic resonance imaging evaluation

Background

Late-onset depression (LOD) is often difficult to recognize when there is an absence of a family history of depression and less severe psychopathology. Increasing evidence has shown that the development and course of LOD symptomatology are associated with cerebrovascular comorbidities and cerebral microvascular lesions. This study was designed to evaluate the associations of LOD with macrovascular and microvascular changes in the brain by using a multi-imaging method, including computed tomography angiography (CTA), CT perfusion (CTP), and magnetic resonance imaging (MRI), to explore the course and pathomechanism of LOD.

Methods

A total of 116 participants were divided into two groups. Participants older than 60 years who met the diagnostic criteria of depression [International Classification of Diseases (ICD), 10th Edition] were enrolled in the LOD group, and the remainder were age- and sex-matched into the control group. The cognitive/mood status of all participants was evaluated by an experienced neuropsychologist. Global and regional mean cerebral blood flow (CBF) were measured by CT cerebrovascular perfusion imaging; the stenosis of the bilateral intracranial large arteries (internal carotid artery, anterior cerebral artery, middle cerebral artery, posterior cerebral artery, and vertebral artery) was recorded by CTA; regional white matter hyperintensity (WMH) loads were evaluated by fluid-attenuated inversion recovery (FLAIR) MRI; and the Hamilton Depression Scale (HAMD) was used to evaluate depression status.

Results

Our key findings were the following: (I) participants in the LOD group were more prone to intracranial arterial stenosis (81.1% vs. 74.6%), had more severe stenotic arteries compared with controls (Z=2.024, P<0.05), and significantly more participants with LOD had severe stenosis of the middle cerebral artery (MCA) (9.4% vs. 0%, P<0.05); (II) there was a significant difference in hypoperfusion of the frontal and parietal lobes superposed on global cerebral hypoperfusion between the two groups (P<0.001); (III) and there was a significant difference in high WMH loads in deep white matter (DWM) between the two groups (P<0.05).

Conclusions

A low global or regional perfusion state, moderate-to-severe stenosis of MCAs, and high WMH loads could be used as imaging biomarkers to indicate diffuse or localized cerebral macrovascular and microvascular pathology in LOD.

Health Care Monitoring and Treatment for Coronary Artery Diseases: Challenges and Issues

In-stent restenosis concerning the coronary artery refers to the blood clotting-caused re-narrowing of the blocked section of the artery, which is opened using a stent. The failure rate for stents is in the range of 10% to 15%, where they do not remain open, thereby leading to about 40% of the patients with stent implantations requiring repeat procedure within one year, despite increased risk factors and the administration of expensive medicines. Hence, today stent restenosis is a significant cause of deaths globally. Monitoring and treatment matter a lot when it comes to early diagnosis and treatment. A review of the present stent monitoring technology as well as the practical treatment for addressing stent restenosis was conducted. The problems and challenges associated with current stent monitoring technology were illustrated, along with its typical applications. Brief suggestions were given and the progress of stent implants was discussed. It was revealed that prime requisites are needed to achieve good quality implanted stent devices in terms of their size, reliability, etc. This review would positively prompt researchers to augment their efforts towards the expansion of healthcare systems. Lastly, the challenges and concerns associated with nurturing a healthcare system were deliberated with meaningful evaluations.

Application of the modified stented elephant trunk procedure in type B aortic dissection

Background

Considering the progressive nature of complicated Stanford type B aortic dissection (TBAD), operation must anticipate the need for later interventions. Recently we have used a modified stent elephant trunk (SET) procedure to treat these patients. And we review the indications, considerations for planning, and operative details for this this modified SET procedure.

Methods

Ten patients (seven males and three females) with complicated TBAD underwent a modified SET procedure in Anzhen Hospital, Beijing in the period between January 2019 and December 2019. The patients, whose ages ranged from 29-52 (42±7.23), suffered complications with hypertension. Under deep hypothermic circulatory arrest, all the patients received SET implantation via an incision of the aortic arch. Before the patients were discharged, a computed tomography angiography (CTA) was performed to ensure the safety and accuracy of the procedure.

Results

The average surgery time was 4.0-5.5 (4.65±0.47) hours, cardiopulmonary bypass (CPB) time was 115-163 (138.6±15.64) minutes, aortic cross-clamping time was 32-59 (42±7.72) minutes, and selective cerebral perfusion (SCP) time was 15-32 (21.7±5.56) minutes. The SCP flow and nasopharyngeal temperature were 5-8 (6.8±1.23) mL/kg/min and 23.5-26.8 (25.22±0.96) °C, respectively. During SCP, the blood pressure of the left upper limb was 20-31 (25.5±3.81) mmHg. Aorta cannulation position: vascular graft was anastomosed to the innominate artery (IA) and left subclavian artery (LSA) in seven cases, and with IA, LSA, and the right femoral artery in three cases. Ventilation time was 5-15 (8.8±2.94) h, retention time in ICU was one day, and post-operative hospitalization time was 6-8 (6.9±0.74) days. None of the patients died, or experienced endoleakage or neurological complications.

Conclusions

The application of a modified stented elephant trunk procedure in the treatment of TBAD is safe and efficient.

Intraluminal fibrous cord of the aorta in the differential diagnosis of aortic dissection

A patient presented with an intraluminal fibrous cord in the distal segment of ascending aorta. On axial images, the fibrous cord had the appearance of an aortic dissection flap. Observation of continuous images and multiplanar reconstruction were critical for differential diagnosis. Volume render images showed both ends of the fibrous cord had tentiform attachments to the aorta inner wall, which indicating a congenital aorta anomaly. One possible hypothesis for the congenital variation might be the fifth primitive aortic arches remnant.

Fully-automatic segmentation of coronary artery using growing algorithm

Currently, cardiac computed tomography angiography (CTA) is widely applied to coronary artery disease diagnosis. Automatic segmentation of coronary artery has played an important role in coronary artery disease diagnosis. In this study, we propose and test a fully automatic coronary artery segmentation method that does not require any human-computer interaction. The proposed method uses a growing strategy and contains three main parts namely, (1) the initial seed detection that automatically detects the root points of the left and right coronary arteries where the ascending aorta meets the coronary arteries, (2) the growing strategy that searches for the neighborhood blocks to decide the existence of coronary arteries with an improved convolutional neural network, and (3) the iterative termination condition that decides whether the growing iteration finishes. The proposed framework is validated using a dataset containing 32 cardiac CTA volumes from different patients for training and testing. Experimental results show that the proposed method obtained a Dice loss ranged from 0.70 to 0.83, which indicates that the new method outperforms the traditional methods such as level set.

[Usefulness of Fenestrated Catheters for i.v. Contrast Infusion Cardiac CT Angiography for Newborn Patients during the Congenital Heart Disease]

PURPOSE

A three-dimensional (3D) image from computed tomography (CT) angiography is a useful method for evaluation of complex anatomy such as congenital heart disease. However, 3D imaging requires high contrast enhancement for distinguishing between blood vessels and soft tissue. To improve the contrast enhancement, many are increasing the injection rate. However, one method is the use of fenestrated catheters, it allows use of a smaller gauge catheter for high-flow protocols. The purpose of this study was to compare the pressure of injection rate and CT number of a 24-gauge fenestrated catheter with an 22-gauge non-fenestrated catheter for i.v. contrast infusion during CT.

METHODS

Between December 2014 and March 2015, 50 newborn patients were randomly divided into two protocols; 22-gauge conventional non-fenestrated catheter (24 newborn; age range 0.25-8 months, body weight 3.6±1.2 kg) and 24-gauge new fenestrated catheter (22 newborn; age range 0.25-12 months, body weight 3.3±0.9 kg). Helical scan of the heart was performed using a 64-detector CT (LightSpeed VCT, GE Healthcare) (tube voltage 80 kV; detector configuration 64×0.625 mm, rotation time 0.4 s/rot, helical pitch 1.375, preset noise index for automatic tube current modulation 40 at 0.625 mm slice thickness).

RESULTS

We compared the maximum pressure of injection rate, CT number of aortic enhancement, and CT number of pulmonary artery enhancement between both protocols. The median injection rate, CT number of aortic enhancement, and CT number of pulmonary artery enhancement were 0.9 (0.5-3.4) ml/s, 455.5 (398-659) HU, and 500.0 (437-701) HU in 22-gauge conventional non-fenestrated catheter and 0.9 (0.5-2.0) ml/s, 436.5 (406-632) HU, and 479.5 (445-695) HU in the 24-gauge fenestrated catheter, respectively. There are no significantly different between a 24-gauge fenestrated catheter and 22-gauge non-fenestrated catheters at injection rate and CT number. Maximum pressure of injection rate was lower with 24-gauge non-fenestrated catheters (0.33 kg/cm²) than 22-gauge non-fenestrated catheters (0.55 kg/cm²) (p<0.01Conclusion: A 24-gauge fenestrated catheter performs similarly to an 22-gauge non-fenestrated catheter with respect to i.v. contrast infusion and aortic enhancement levels and can be placed in most subjects whose veins are deemed insufficient for an 22-gauge catheter.

Over-utilization of computed tomography angiography in extremity trauma

Objectives:

Widespread availability of computed tomography angiography (CTA) for diagnosing arterial injury in injured extremities has created the possibility of overuse. The objective of this study was to evaluate CTA utilization, indications, ordering personnel, and rate of significant findings for blunt or penetrating extremity trauma at a level I trauma center.

Methods:

We performed a retrospective chart review of 1440 consecutive CTAs of upper and lower extremities from 2010 to 2012 at a large level I trauma center, and included only those done for acute trauma. Data were collected with regard to injury, initial exam, reason given for ordering a CTA, specialty of physician ordering CTA, results, and vascular interventions needed. CTAs were categorized as appropriately ordered based on if there was a documented abnormal distal pulse or ankle-brachial index (ABI). Study indication was classified as inconclusive if no vascular exam was documented or physical exam varied.

Results:

A total of 481 CTAs were performed after blunt or penetrating trauma in the emergency room with 31.0% appropriately indicated, 48.0% without indication, and 21.8% inconclusive. Mechanism of injury was most commonly a gunshot wound (40.3%), followed by motor vehicle accidents (39.5%). Overall, 61.5% of the studies had normal arterial flow and only 15.8% of CTAs required vascular operative intervention. Of the studies appropriately indicated, 76.5% had positive findings, with 43% needing operative intervention compared to the inappropriately indicated studies only 11.6% had positive findings, with 0.4% needing operative intervention (P < .0001).

Conclusion:

CTA for blunt or penetrating trauma at a level I trauma center may be over-utilized. Often, this advanced imaging is ordered prior to orthopaedic evaluation or limb reduction, without exam-based indication, and most do not affect patients’ treatment. From our study, CTA utilization based on more stringent exam findings at our hospital could eliminate 48% of all CTA studies for trauma.

The role of imaging in gastrointestinal bleed

Gastrointestinal (GI) bleed accounts for approximately 20% of emergency visits; 2% of hospital admissions and its incidence has been increasing. In patients where the GI bleed does not stop spontaneously, intervention is required to identify the source of bleeding and stop the hemorrhage. Although identifying the source of bleeding can be challenging due to the vast number of underlying etiologies, radiology plays a vital role in patients where endoscopy and/or medical management fail. Radiology offers both non-invasive and invasive options for the diagnosis as well as management of GI bleeds. Scintigraphy and computed tomography angiography (CTA) are the most important non-invasive imaging tests that can identify presence of and help locate the site of bleeding and are used when the patient is hemodynamically stable. If the patient is hemodynamically unstable, conventional angiography (CA) allows diagnosis of the presence, site of bleeding as well as the means of treating the bleed by embolization. Our review article focuses on the various etiologies of GI bleed, the role of imaging in diagnosis as well as treatment of these patients based on the underlying etiologies, the merits and disadvantages of each of these modalities with emphasis on triaging patients for the most appropriate imaging test to guide the most suitable management.

Retrospective evaluation of a clinical decision support tool for effective computed tomography angiography utilization in urgent brain imaging of suspected TIA/minor stroke in the emergency department

OBJECTIVES

The Canadian Stroke Best Practice Recommendations suggests that patients suspected of transient ischemic attack (TIA)/minor stroke receive urgent brain imaging, preferably computed tomography angiography (CTA). Yet, high requisition rates for non-cerebrovascular patients overburden limited radiological resources, putting patients at risk. We hypothesize that our clinical decision support tool (CDST) developed for risk stratification of TIA in the emergency department (ED), and which incorporates Canadian guidelines, could improve CTA utilization.

METHODS

Retrospective study design with clinical information gathered from ED patient referrals to an outpatient TIA unit in Victoria, BC, from 2015-2016. Actual CTA orders by ED and TIA unit staff were compared to hypothetical CTA ordering if our CDST had been used in the ED upon patient arrival.

RESULTS

For 1,679 referrals, clinicians ordered 954 CTAs. Our CDST would have ordered a total of 977 CTAs for these patients. Overall, this would have increased the number of imaged-TIA patients by 89 (10.1%) while imaging 98 (16.1%) fewer non-cerebrovascular patients over the 2-year period. Our CDST would have ordered CTA for 18 (78.3%) of the recurrent stroke patients in the sample.

CONCLUSIONS

Our CDST could enhance CTA utilization in the ED for suspected TIA patients, and facilitate guideline-based stroke care. Use of our CDST would increase the number of TIA patients receiving CTA before ED discharge (rather than later at TIA units) and reduce the burden of imaging stroke mimics in radiological departments.

Repair of abdominal aortic aneurysms: preoperative imaging and evaluation

Imaging is a critical component of the pre-procedure evaluation and planning of endovascular aneurysm repair (EVAR). Imaging is the mainstay for proper assessment of procedural candidacy, relevant vascular anatomy, device selection, and surgical approach. Computed tomography angiography (CTA) has long been considered the preferred modality for pre-operative imaging and evaluation prior to EVAR. Recently, advances in image quality and software technology have further enhanced the proceduralist's ability to plan and perform EVAR. In this review, we highlight the current state of the art to provide interventionalists a contemporary assessment of the available tools for pre-operative imaging and evaluation prior to EVAR.

Current status of the treatment of infrarenal abdominal aortic aneurysms

Aortic aneurysms are the 13^th leading cause of death in the United States. While aneurysms can occur along the entire length of the aorta, the infrarenal location is the most common. Targeted ultrasound screening has been found to be an effective and economical means of preventing aortic aneurysm rupture. The indication for repair includes either symptomatic aneurysms or aneurysms with a diameter greater than 5.4 cm. Treatment options for the repair of infrarenal aortic aneurysms are open surgical repair (OSR) and endovascular aneurysm repair (EVAR). Currently, EVAR is the primary treatment method for the repair of infrarenal aortic aneurysms due to improved short-term morbidity and mortality outcomes. This article is intended to review the current status of the management of infrarenal abdominal aortic aneurysms (AAA).

Congenital anomalies of the aortic arch

Congenital anomalies of the aortic arch include diverse subgroups of malformations that may be clinically silent or may present with severe respiratory or esophageal symptoms especially when associated with complete vascular rings. These anomalies may be isolated or may be associated with other congenital heart diseases. Volume rendered computed tomography (CT) and magnetic resonance angiography (MRA) help in preoperative surgical planning by providing information about the complex relationship of aortic arch and its branches to the trachea and esophagus. Three dimensional capabilities of both computed tomography angiography (CTA) and MRA are helpful in determining evidence of tracheal or esophageal compression or other high-risk features in patients with a complete vascular ring.

Postoperative imaging of the aorta

Considerable progress has been made in the management of diseases of the thoracic and abdominal aorta over the past decades, ranging from advances in open repair to the advent of minimally invasive endovascular techniques. Along with this comes an equivalent rise in imaging necessity for these patients, both in preoperative planning and postoperative surveillance. With the growing complexity and diversity of vascular procedures and techniques, it is essential to have a solid understanding of the imaging features and postoperative complications of these procedures to avoid imaging pitfalls. This review is an attempt to define the normal postoperative appearance and important complications of various open and endovascular surgical techniques of the thoracic and abdominal aorta.

Seismocardiography-Based Cardiac Computed Tomography Gating Using Patient-Specific Template Identification and Detection

To more accurately trigger cardiac computed tomography angiography (CTA) than electrocardiography (ECG) alone, a sub-system is proposed as an intermediate step toward fusing ECG with seismocardiography (SCG). Accurate prediction of quiescent phases is crucial to prospectively gating CTA, which is susceptible to cardiac motion and, thus, can affect the diagnostic quality of images. The key innovation of this sub-system is that it identifies the SCG waveform corresponding to heart sounds and determines their phases within the cardiac cycles. Furthermore, this relationship is modeled as a linear function with respect to heart rate. For this paper, B-mode echocardiography is used as the gold standard for identifying the quiescent phases. We analyzed synchronous ECG, SCG, and echocardiography data acquired from seven healthy subjects (mean age: 31; age range: 22–48; males: 4) and 11 cardiac patients (mean age: 56; age range: 31–78; males: 6). On average, the proposed algorithm was able to successfully identify 79% of the SCG waveforms in systole and 68% in diastole. The simulated results show that SCG-based prediction produced less average phase error than that of ECG. It was found that the accuracy of ECG-based gating is more susceptible to increases in heart rate variability, while SCG-based gating is susceptible to high cycle to cycle variability in morphology. This pilot work of prediction using SCG waveforms enriches the framework of a comprehensive system with multiple modalities that could potentially, in real time, improve the image quality of CTA.

Cystic adventitial disease-case series and review of literature

Cystic adventitial disease (CAD) is a rare vascular disorder that involves the arteries and rarely the veins, most commonly found in the popliteal artery of male patients. Etiology of CAD is uncertain and currently without a consensus agreement. Clinically, the most common presenting symptom is claudication. Diagnosis requires a strong clinical suspicion in patients with intermittent claudication, but without other risk factors for atherosclerotic disease. Angiography, ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) can all be used for diagnosis. Treatment of CAD can be done via surgical resection or percutaneous intervention such as aspiration. CAD can rarely recur after treatment.

Software-based on-site estimation of fractional flow reserve using standard coronary CT angiography data

BACKGROUND

The significance of a coronary stenosis can be determined by measuring the fractional flow reserve (FFR) during invasive coronary angiography. Recently, methods have been developed which claim to be able to estimate FFR using image data from standard coronary computed tomography angiography (CCTA) exams.

PURPOSE

To evaluate the accuracy of non-invasively computed fractional flow reserve (cFFR) from CCTA.

MATERIAL AND METHODS

A total of 23 vessels in 21 patients who had undergone both CCTA and invasive angiography with FFR measurement were evaluated using a cFFR software prototype. The cFFR results were compared to the invasively obtained FFR values. Correlation was calculated using Spearman's rank correlation, and agreement using intraclass correlation coefficient (ICC). Sensitivity, specificity, accuracy, negative predictive value, and positive predictive value for significant stenosis (defined as both FFR ≤0.80 and FFR ≤0.75) were calculated.

RESULTS

The mean cFFR value for the whole group was 0.81 and the corresponding mean invFFR value was 0.84. The cFFR sensitivity for significant stenosis (FFR ≤0.80/0.75) on a per-lesion basis was 0.83/0.80, specificity was 0.76/0.89, and accuracy 0.78/0.87. The positive predictive value was 0.56/0.67 and the negative predictive value was 0.93/0.94. The Spearman rank correlation coefficient was ρ = 0.77 (P < 0.001) and ICC = 0.73 (P < 0.001).

CONCLUSION

This particular CCTA-based cFFR software prototype allows for a rapid, non-invasive on-site evaluation of cFFR. The results are encouraging and cFFR may in the future be of help in the triage to invasive coronary angiography.

Noninvasive testing strategies in symptomatic, intermediate-risk CAD patients: a perspective on the "PROMISE" trial and its potential implementation in clinical practice

While the results of the Prospective Multicenter Imaging Study for Evaluation of Chest Pain trial (PROMISE trial) are negative for the primary outcome, the results from this large, contemporary trial of >10,000 patients provide important insights into clinical management of patients presenting with chest pain. The results reinforce that while diagnostic testing is an important component of modern management, its choice should be directed by a clinician in a clinical context and with subsequent management in mind. Based on presentation and pre-test probability, the clinician will decide if any additional testing necessary is necessary and if that is the case chose the most appropriate test according to current guidelines, applied to the individual patient and clinical scenario.

CT angiography in the diagnosis of cardiovascular disease: a transformation in cardiovascular CT practice

Computed tomography (CT) angiography represents the most important technical development in CT imaging and it has challenged invasive angiography in the diagnostic evaluation of cardiovascular abnormalities. Over the last decades, technological evolution in CT imaging has enabled CT angiography to become a first-line imaging modality in the diagnosis of cardiovascular disease. This review provides an overview of the diagnostic applications of CT angiography (CTA) in cardiovascular disease, with a focus on selected clinical challenges in some common cardiovascular abnormalities, which include abdominal aortic aneurysm (AAA), aortic dissection, pulmonary embolism (PE) and coronary artery disease. An evidence-based review is conducted to demonstrate how CT angiography has changed our approach in the diagnosis and management of cardiovascular disease. Radiation dose reduction strategies are also discussed to show how CT angiography can be performed in a low-dose protocol in the current clinical practice.

Medial sural artery perforator flap aided by preoperative computed tomography angiography mapping for tongue reconstruction

The purpose of this paper is to present an innovative method for tongue reconstruction after cancer ablation using the medial sural artery perforator flap with the aid of preoperative computed tomography angiography (CTA) mapping. We describe the case of one patient treated with this technique and illustrate the anatomy of perforator vessels and the surgical techniques used in flap harvest. CTA was applied preoperatively to assess the number and location of medial sural artery perforators. The result obtained was both aesthetically and functionally satisfactory. The flap presented has the advantage of less donor site morbidity, and being thin, it is a suitable option for tongue reconstruction including that of a hemiglossectomy defect. CTA is an effective means of improving the safety of flap harvest.

Cranial dural arteriovenous fistula as a rare cause of tinnitus - case report

Background

Tinnitus, occurring at least once in a lifetime in about 10–20% of the population, is an important clinical problem with complex etiology. Rare causes of tinnitus include cranial dural arteriovenous fistulas (DAVFs), which are usually small lesions consisting of abnormal connections between branches of dural arteries and venous sinuses or veins.

Case Report

Authors present a case of a 44-year-old woman with persistent, unilateral, treatment-resistant pulsatile tinnitus caused by a small dural arteriovenous fistula revealed in computed tomography angiography.

Conclusions

Computed tomography angiography is a useful diagnostic method that in some cases allows for establishing the cause of unilateral, pulsatile tinnitus.

Imaging difficulties in Takayasu arteritis - case report and review of the literature

Background:

Takayasu arteritis is an inflammatory disease of large-diameter arteries. Aorta and its branches are most frequently affected. Takayasu arteritis occurs mainly in young women and, if left untreated, leads to fatal complications. Digital subtraction angiography (DSA) is considered the gold standard in imaging of Takayasu arteritis.

Case Report:

A thirty-five-year-old woman was admitted to the hospital with transient loss of consciousness, effort-associated vertigo, upper limb weakness and temporary vision problems. On admission, there was no pulse on the left radial artery while there were bruits over subclavian arteries. Imaging of the aortic arch (computed tomography angiography, DSA) revealed stenoses of its main branches, indicating Takayasu arteritis.

Conclusions:

Computed tomography angiography (CTA) performed with a 64-slice unit revealed high effectiveness in localization of vascular wall and lumen pathologies resulting from Takayasu arteritis. Thanks to this fast diagnostic method, it is now possible to perform successful monitoring of patients with Takayasu arteritis and to plan possible interventional treatment.