Computed Tomography Angiography Research Articles

Decision analytical modelling of strategies for investigating suspected acute aortic syndrome.

Acute aortic syndrome (AAS) requires urgent diagnosis with computed tomographic angiography (CTA). Diagnostic strategies need to weigh the benefits of detecting AAS against the costs of using CTA with a low yield of AAS when the prevalence of AAS is low. We aimed to estimate the cost-effectiveness of diagnostic strategies using clinical probability scoring and D-dimer to select patients with potential symptoms of AAS for CTA. We developed a decision analytical model to simulate the management of patients attending hospital with possible AAS. We modelled diagnostic strategies that used the Aortic Dissection Detection Risk Score (ADD-RS) and D-dimer to select patients for CTA. We used estimates from our meta-analysis, existing literature and clinical experts to model the consequences of diagnostic strategies on survival, health utility, and health and social care costs. We estimated the incremental cost per quality-adjusted life-years gained by each strategy compared with the next most effective alternative on the efficiency frontier. A strategy based on the Canadian guideline (CTA if ADD-RS>1 or ADD-RS=1 with D-dimer >500 ng/mL) is cost-effective but would result in high rates of CTA if applied to an unselected population (AAS prevalence 0.26%). The strategy is also cost-effective and would result in lower rates of CTA if applied to a more selected population, such as those with a non-zero clinical suspicion of AAS (prevalence 0.61%). For patients currently receiving CTA, using ADD-RS>1 or D-dimer >500 ng/mL to select patients for CTA is cost-effective. A strategy using ADD-RS>1 or ADD-RS=1 with D-dimer >500 ng/mL to select patients for CTA appears cost-effective but primary research is required to evaluate this strategy in practice and determine how suspicion of AAS is identified.

Enhanced Preoperative Planning for Intracranial Aneurysms Through Multimodal Image Fusion of Silent/Time-of-Magnetic Resonance Angiography and Computed Tomography Using 3DSlicer: A Comparative Efficacy Analysis With Computed Tomography Angiography.

This study evaluates the effectiveness of multimodal image fusion (MIF) using silent and time-of-flight (TOF) magnetic resonance angiography (MRA) and computed tomography (CT) for preoperative planning in patients with intracranial aneurysms who have contraindications to contrast media. A retrospective study included 40 patients with intracranial aneurysms, diagnosed using three-dimensional computed tomography angiography (CTA). These patients underwent both Silent and TOF MRA scans, followed by a CTA scan. The multi-image fusion (MIF) technique, applied using 3DSlicer software, integrated the silent/TOF-MRA with CT images for preoperative assessment. This study compared the image quality, aneurysm detection sensitivity, and anatomic accuracy of the MIF images with those of three-dimensional CTA. Silent-MRA-CT fusion images demonstrated higher sensitivity (95.5%) and lower false negative rates (4.5%) compared with TOF-MRA-CT. Furthermore, silent-MRA-CT fusion images outperformed TOF-MRA-CT in terms of signal homogeneity, venous signal interference suppression, and aneurysm visibility (all P < 0.05). The interclass correlation coefficient and kappa values for aneurysm morphology and shape indicated superior measurement consistency and shape concordance of silent-MRA-CT with CTA compared with TOF-MRA-CT (all P < 0.01). This study supports the use of silent/TOF-MRA-CT fusion imaging as a reliable alternative to CTA, noting that silent-MRA-CT closely mirrors CTA. Contrast-free MRA-CT fusion images have the potential to be used for preoperative planning in patients with intracranial aneurysms who have contraindications to contrast.

The benefit of automated sac volume measurements in postoperative endovascular aortic repair surveillance

Abdominal aortic aneurysm (AAA) shrinkage is considered a marker for success following endovascular aortic repair (EVAR). Although maximum diameter is widely used to assess sac behavior, research indicates that changes in AAA morphology do not always affect the maximum diameter. The aim of this study is to investigate if automated AAA sac volume measurements after EVAR can add more nuanced information on sac behavior compared with maximum diameter evaluation alone. A retrospective review of all patients treated for AAA with a standard or fenestrated EVAR at two tertiary referral centers was performed. Patients with a pre- and postoperative computed tomography angiography (CTA) ≥ two years after treatment were included. Data were collected using medical charts, radiologic institutional databases, and a deep learning based method called Augmented Reality for Vascular Aneurysm (ARVA). Volume and diameter assessments were automatically performed on CTAs using ARVA. Preoperative sac volumes and diameters were compared with those obtained at least two years after repair. Information on endoleaks (ELs) was collected. Continuous data were tested using t-test, and categorical data were tested using chi-square or Fishers test, depending on sample size. A total of 89 patients (standard EVAR n=46; fenestrated EVAR n=43) were included in this study. Of the 89 patients, 41 (46%) had sac diameter shrinkage, 38 (43%) had stable sac diameters, and 10 (11%) had diameter sac growth during follow-up. The distribution of sac volume behavior was different amongst these patients: 51 (57%) had volume shrinkage, only 9 (10%) had stable volumes, and 29 (33%) had volume growth. Significantly more patients had sac growth, and fewer had sac stability, when assessed with volume compared with diameter, p=.003 and p<.001, respectively. The increase in patients with volume-assessed sac shrinkage (57% vs 46%) was not statistically significant. Of the 18 (20%) patients with stable sac diameters and simultaneous volume growth, 13 (72%) had ELs (T2ELs: n=9, T1ELs, n=2, T3EL: n=1, and EL of undefined origin: n=1). This study found that volume-assessed sac behavior identifies more sac shrinkage or growth, and less sac stability than diameter does. If confirmed by larger studies, sac volume assessment should be performed routinely after endovascular repair.

Finding MeVO: Identifying Intracranial Medium-Vessel Occlusions at CT Angiography.

The development of methods to detect and treat intracranial large-vessel occlusions (LVOs) has revolutionized the management of acute ischemic stroke. CT angiography (CTA) of the head and neck is effective in depicting LVOs and widely used in the evaluation of patients who have had a stroke. Ongoing efforts are now focused on the potential to detect and treat intracranial medium-vessel occlusions (MeVOs), which by definition are smaller than LVOs and thus more difficult to detect with CTA. The authors review common and variant anatomies of medium-sized cerebral arteries and the appearance of a variety of MeVOs on CT angiograms. Possible pitfalls in MeVO detection include rare anatomic variants, calcified thrombi, and stump occlusions. Current recommendations for performing CTA and ancillary methods that might aid in MeVO detection are discussed. Understanding the relevant anatomy and the variety of appearances of MeVOs aids radiologists in identifying these occlusions, particularly in the setting of urgent stroke. ©RSNA, 2024 See the invited commentary by Ospel and Nguyen in this issue.

Diagnostic performance of Photon-counting CT angiography in peripheral artery disease compared to DSA as gold standard

BackgroundPhoton-counting (PC) CT has the potential to improve diagnostic confidence and image quality of CT angiography (CTA) in patients with peripheral artery disease (PAD). PurposeTo retrospectively evaluate the diagnostic performance of Photon-counting CT angiography for the assessment of stenotic disease in patients with PAD compared to digital subtraction angiography (DSA) as gold standard. Materials and MethodsAll patients undergoing PC CTA followed by DSA between November 2021 and November 2023 were included in this institutional review board approved HIPAA compliant retrospective analysis. The arterial vasculature of the lower extremity was divided into 10 segments from the iliac vasculature to the calf arterial vasculature. The images were evaluated independently by two experienced readers. Inter-reader agreement was determined using Cohen’s kappa coefficient (κ). Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) as well as accuracy were calculated for PC CTA and PC pure lumen reconstruction compared to DSA as gold standard. Results109 patients (mean age 74.68 ± 11.10 years; 77 males, 32 females) were included in the retrospective analysis. PC pure lumen reconstructions was available for 91 patients (83 %). A total of 933 vascular segments for PC CTA and 780 vascular segments for PC pure lumen reconstruction were evaluated. Good to perfect inter-reader agreement was found for PC CTA (κ = 0.791) and for PC pure lumen reconstruction (κ = 0.829). Sensitivity, Specificity and accuracy for PC CTA were 91 %; 95 % and 93 %, respectively. Sensitivity, Specificity and accuracy for PC pure lumen reconstruction were 85 %, 89 % and 88 %, respectively. ConclusionPhoton-counting CTA demonstrates high sensitivity and specificity for the detection and diagnosis of stenotic lesions in PAD. PC non-calcium reconstruction does not further increase the accuracy compared to PC CTA.

Dual‐Low Technology in Coronary and Abdominal CT Angiography: A Comparative Study of Deep Learning Image Reconstruction and Adaptive Statistic Iterative Reconstruction‐Veo

ABSTRACTTo investigate the application advantages of dual‐low technology (low radiation dose and low contrast agent dose) in deep learning image reconstruction (DLIR) compared to the adaptive statistical iterative reconstruction‐Veo (ASIR‐V) standard protocol when combing coronary computed tomography angiography (CCTA) and abdominal computed tomography angiography (ACTA). Sixty patients who underwent CCTA and ACTA were recruited. Thirty patients with low body mass index (BMI) (&lt; 24 kg/m2, Group A, standard protocol) were reconstructed using 60% ASIR‐V, and 30 patients with high BMI (&gt; 24 kg/m2, Group B, dual‐low protocol) were reconstructed using DLIR at high strength (DLIR‐H). The effective dose and contrast agent dose were recorded. The CT values, standard deviations, signal‐to‐noise ratio (SNR), and contrast‐to‐noise ratio (CNR) were measured. The subjective evaluation criteria were scored by two radiologists using a blind Likert 5‐point scale. The general data, objective evaluation, and subjective scores between both groups were compared using corresponding test methods. The consistency of objective and subjective evaluations between the two radiologists were analyzed using Kappa tests. Group B showed a remarkable 44.6% reduction in mean effective dose (p &lt; 0.01) and a 20.3% decrease in contrast agent dose compared to Group A (p &lt; 0.01). The DLIR‐H demonstrated the smallest standard deviations and highest SNR and CNR values (p &lt; 0.01). The subjective score of DLIR‐H was the highest (p &lt; 0.01), and there was good consistency between the two radiologists in the subjective scoring of CCTA and ACTA image quality (κ = 0.751 ~ 0.919, p &lt; 0.01). In combined CCTA and ACTA protocols, DLIR can significantly reduce the effective dose and contrast agent dose compared to ASIR‐V while maintaining good image quality.

Vasospasm in Pediatric Subarachnoid Hemorrhage.

Cerebral vasospasm (CV) is a common severe complication of subarachnoid hemorrhage (SAH), a severe type of intracranial bleeding that is uncommon in children. The purpose of this article is to review the current literature regarding this potentially devastating complication. CV may be asymptomatic and is less common in children compared to adults. Several molecular phenomena, including inflammatory ones, contribute to its pathophysiology. Better collateral circulation and higher cerebral blood flow are protective factors in children. When clinically apparent, CV may manifest as a change in the child's neurologic status or vital signs. CV can be diagnosed using brain vessel imaging, such as computed tomography angiography, magnetic resonance angiography, digital subtraction angiography, transcranial Doppler ultrasonography, and computed tomography perfusion. A reduction of < 50% in the artery's caliber confirms the diagnosis. Besides general supportive measures and causative treatment of SAH, CV management options include the administration of calcium channel blockers and neurointerventional approaches, such as intra-arterial vasodilators and balloon angioplasty. Long-term outcomes in children are usually favorable.

Feasibility of Ultra-low Radiation and Contrast Medium Dosage in Aortic CTA Using Deep Learning Reconstruction at 60 kVp: An Image Quality Assessment

ObjectiveTo assess the viability of using ultra-low radiation and contrast medium (CM) dosage in aortic computed tomography angiography (CTA) through the application of low tube voltage (60kVp) and a novel deep learning image reconstruction algorithm (ClearInfinity, DLIR-CI). MethodsIodine attenuation curves obtained from a phantom study informed the administration of CM protocols. Non-obese participants undergoing aortic CTA were prospectively allocated into two groups and then obtained three reconstruction group. The conventional group (100kVp-CVgroup) underwent imaging at 100kVp and received 210 mg iodine/kg in combination with a hybrid iterative reconstruction algorithm (ClearView, HIR-CV). The experimental group was imaged at 60kVp with 105 mg iodine/kg, while images were reconstructed with HIR-CV (60 kVp-CV group) and with DLIR-CI (60 kVp-CI group). Student's t-test was used to compare differences in CM protocol and radiation dose. One-way ANOVA compared CT attenuation, image noise, SNR, and CNR among the three reconstruction groups, while the Kruskal-Wallis H test assessed subjective image quality scores. Post hoc analysis was performed with Bonferroni correction for multiple comparisons, and consistency analysis conducted in subjective image quality assessment was measured using Cohen's kappa. ResultsThe radiation dose (1.12±0.23 mSv vs. 2.03±0.82 mSv) and CM dosage (19.04±3.03 mL vs. 38.11±6.47 mL) provided the reduction of 45% and 50% in the experimental group compared to the conventional group. The CT attenuation, SNR and CNR of 60kVp-CI were superior to or equal to those of 100kVp-CV. Compared to the 60 kVp-CV group, images in 60kVp-CI showed higher SNR and CNR (all P < 0.001). There was no difference between the 60kVp-CI and 100kVp-CVgroup in terms of the subjective image quality of the aorta in various locations (all P > 0.05), with 60kVp-CI images were deemed diagnostically sufficient across all vascular segments. ConclusionsFor non-obese patients, the combined use of 60kVp and DLIR-CI algorithm can preserving image quality while enabling radiation dose and contrast medium savings for aortic CTA compared with 100kVp using HIR-CV.

[Translated article] Thrombotic Event Prevention in Patients Undergoing Posterior Lumbar Arthrodesis: our experiencie. A retrospective case series study

There is no generalized consensus regarding perioperative prophylaxis of venous thromboembolism (VTE), either on using or timing it in patients undergoing spine surgery. VTE is a current concern because, even though being an uncommon event, it can cause serious complications. The aim of the present study is to propose guidelines for the prevention of thrombotic events in posterior spinal surgery, either as deep vein thrombosis or pulmonary thromboembolism. If the number of patients getting prophylaxis drugs is reduced a subsequent reduction of the incidence of epidural hematoma can be expected. A number of 235 patients who had undergone posterior spinal arthrodesis in the previous five years were studied. Mechanical thromboprophylaxis measures consisting of compression stockings were applied in all of them. Anticoagulant drugs were also applied whenever risk factors for thrombosis were observed. Early weight-bearing was resumed immediately after surgery. Demographic, clinical, and surgical variables were collected, as well as complications appearing during the follow-up period, that was scheduled at one, two, four, six and twelve months after the surgery. Thrombotic events, if present, were diagnosed by clinical and imaging tests such as ultrasound and CT angiography. From the total 235 patients of this series, one hundred and fifty-three cases met the study inclusion criteria. A total of four thrombotic events appeared, one in the form of deep vein thrombosis and other three in the form of pulmonary thromboembolism. These last patients suffering an embolism died because of it. None of the variables studied had statistical significance for the occurrence of a thrombotic event. All four patients who suffered thrombotic events were receiving anticoagulant drugs, in addition to mechanical compression stockings, because of the presence of risk factors for thrombosis. By applying the fore mentioned protocol, adequate prevention of thromboembolic events was achieved in this study population of patients undergoing posterior spinal surgery.

Angiographic reconstructions of CT perfusion for occlusion detection in ischemic stroke

BackgroundBoth CT angiography and CT perfusion involve the administration and tracking of a contrast medium bolus for different purposes. In this study, we aim to compare the diagnostic accuracy and subjective image quality of CTP-angiographic reconstructions with conventional CTA for occlusion detection in ischemic stroke patients. MethodsIn this retrospective study, patients with a final diagnosis of ischemic stroke and who underwent both CTA and CTP from September 2020 up to and including September 2021 were included. CTP-AR was reconstructed from the 1 mm CTP series at the time of maximum arterial inflow. Three readers with different levels of experience assessed both CTA and CTP for occlusion detection, expressed certainty, and rated subjective image quality. The reference standard was set at the consensus meeting. Pooled sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Differences in subjective and objective image quality and certainty were assessed using Kendall’s tau correlation and paired samples t-tests. ResultsIn total, 107/210 included patients had an occlusion based on our reference standard. Pooled sensitivity and specificity for occlusion detection were 90 % (95 %CI 85–93 %) and 94 % (95 %CI 90–97 %) for CTA, and 89 % (95 %CI 84–93 %) and 93 % (95 %CI 89–96) for CTP-AR, respectively. The pooled certainty did not significantly differ between CTA and CTP-AR (P=.43). The pooled subjective image quality scores significantly differed between CTA and CTP-AR (τ = 0.3, P < 0.001), where one reader rated subjective image quality higher in CTA and two readers in CTP-AR. ConclusionCTP-AR has comparable diagnostic accuracy to conventional CTA imaging for occlusion detection in ischemic stroke patients. Thus, using CTP-AR instead of CTA plus CTP may conserve contrast medium.

Diagnostic performance of CCTA and CTP imaging for clinically suspected in-stent restenosis: A meta-analysis

AimsThe objective of this study is to conduct a meta-analysis to assess the diagnostic performance of Coronary Computed Tomography Angiography (CCTA) and a hybrid approach that incorporates Computed Tomography Perfusion (CTP) in addition to CCTA (CCTA ​+ ​CTP) for the detection of in-stent restenosis (ISR), as defined by angiography. MethodsA comprehensive search of articles identified 18,513 studies. After removing duplicates, title/abstract screening, and full-text review, 17 CCTA and 3 CCTA ​+ ​CTP studies were included. Only studies using ≥64-slices multidetector computed tomography (CT) were considered eligible. ResultsThe per-patient ISR prevalence was 43 ​%, with 92 ​% of stents fully interpretable with CCTA. Meta-analysis exhibited a per-stent CCTA (n ​= ​2674) sensitivity of 90 ​% (95 ​% CI; 84–94 ​%), specificity of 89 ​% (95 ​% CI; 86–92 ​%), positive likelihood ratio of 7.17 (95 ​% CI; 5.24–9.61), negative likelihood ratio of 0.17 (95 ​% CI; 0.10–0.25), and diagnostic odds ratio of 45.7 (95 ​% CI; 22.71–82.43). Additional sensitivity analyses revealed no influence of stent diameter or strut thickness on the diagnostic yield of CCTA. The per-stent diagnostic performance of CCTA ​+ ​CTP (n ​= ​752) did not show differences compared to CCTA. ConclusionsWith currently utilized scanners, CCTA and CCTA ​+ ​CTP demonstrated high diagnostic performance for in-stent restenosis evaluation. Consequently, a history of previous stent implantation should not be an argument to preclude using these methods in clinically suspected patients.

GSOR07 Presentation Time: 5:30 PM: Using Three-Dimensional Computed Tomography Angiography for Needle Insertion in Interstitital Brachytherapy for Locallly Advanced Cervix Cancer

GSOR07 Presentation Time: 5:30 PM: Using Three-Dimensional Computed Tomography Angiography for Needle Insertion in Interstitital Brachytherapy for Locallly Advanced Cervix Cancer

Association of coronary inflammation with plaque vulnerability and fractional flow reserve in coronary artery disease

BackgroundThe fat attenuation index (FAI) measured using coronary computed tomography angiography (CCTA) enables the direct evaluation of pericoronary adipose tissue composition and vascular inflammation. We aimed to investigate the association of fractional flow reserve (FFR) and plaque vulnerability with coronary inflammation. MethodsPatients with suspected coronary artery disease (CAD) who underwent CCTA and invasive FFR measurements within 90-day were included. A cloud-based medical device, CaRi-Heart, serves as a surrogate tool for evaluating coronary inflammation based on FAI by analyzing CCTA images. The correlations between CCTA-defined plaque characteristics, invasive coronary angiographic and physiologic assessments, and CaRi-Heart risk were analyzed. The primary endpoint was the patient-oriented composite outcome (POCO) consisting of all-cause death, any myocardial infarction, and any revascularization. ResultsA total of 564 patients (median age 67.0 years; 75.4 ​% men) were included. There were no significant differences in quantitative and qualitative plaque characteristics or FFR between the high- and low-CaRi-Heart risk groups (i.e., ≥5 ​% and <5 ​%). During the median follow-up of 3.2 years [1.13–4.73 years], CaRi-Heart risk ≥5 ​% was associated with a significantly higher rate of POCO compared to CaRi-Heart risk <5 ​% (0.9 ​% vs. 10.1 ​%, P ​= ​0.037). The CaRi-Heart risk was an independent predictor of POCO as a continuous (adjusted HR 1.016, 95 ​% CI 1.005–0.027, P ​= ​0.004) and categorical variable (CaRi-Heart risk ≥5 ​%, adjusted HR 2.949, 95 ​% CI 1.182–7.360, P ​= ​0.021), regardless of high-risk plaque characteristics and FFR. ConclusionCoronary inflammation risk assessed using CaRi-Heart risk provides independent prognostic information regardless of plaque vulnerability and physiologic stenosis in patients with CAD.

The Effect of Leg Dominance in Patients on Perforator-Based Flaps Elevated From the Lower Extremities.

The lower extremities are the largest donor sites in the body for perforator flap reconstruction. Multislice row computed tomography angiography allows for a multiplanar assessment of perforators using a large number of three-dimensional images with high resolution. In this study, the effect of leg dominance on perforator flap donor site preference was investigated radiologically to increase preoperative perforator mapping precision and surgical success. The study included 40 patients. Superior gluteal artery perforator (SGAP) flap, inferior gluteal artery perforator (IGAP) flap, superficial circumflex iliac artery perforator flap, anterolateral thigh (ALT) flap, profunda artery perforator (PAP) flap, medial sural artery perforator (MSAP) flap, peroneal artery perforator (PP) flap, and posterior tibial artery perforator (PTAP) flap were analyzed according to their number of perforators (> 0.8-mm perforators counted, number of larger perforators [nLP]), dominant perforator diameter (DPD), related muscle thickness (RMT), and related subcutaneous tissue thickness (RSTT) in each leg. Of these 40 patients, 35 (87.5%) were right-leg dominant and 5 (12.5%) were left-leg dominant. The dominant leg had higher DPD for MSAP, PTAP, and PP than the nondominant leg (p = 0.08, p = 0.06, and p = 0.06, respectively). The dominant leg had a significantly higher nLP (> 0.8 mm) in MSAP, PTAP, and PP flaps than the nondominant leg (p < 0.05). Except for the PAP flap (adductor magnus muscle; p > 0.05), RMT of all other perforator flaps (SGAP, IGAP, ALT, MSAP, PTAP, and PP) was statistically higher in the dominant leg (p < 0.05). There was no statistically significant difference in RSTT between any of the two groups (p > 0.05). According to findings, the dominant leg could be considered a donor site preference to improve surgical outcomes and reduce microsurgical complications due to an increased nLP, perforator diameter, and RMT.

Prognostic value of left ventricular mass measured on coronary computed tomography angiography

BackgroundLeft ventricular (LV) mass is a well-established prognostic indicator for cardiovascular risk. Measurement of LV mass on coronary computed tomography angiography (CCTA) is considered optional. We aimed to assess for associations between LV mass measured on CCTA with all-cause mortality (ACM) risk and to determine age- and sex-specific distributions. MethodsWe evaluated patients without known coronary artery disease (CAD) who underwent CCTA at a single center. We assessed age- and sex-specific distributions (10th, 25th, 50th, 75th, and 90th percentiles) of LV mass index. ACM, the primary endpoint, was recorded over a median period of 5.1 [interquartile range: 1.4–8.4] years. The association between LV mass and mortality risk was assessed using multivariable Cox models adjusted for age, sex, medical history, coronary artery calcium (CAC) score and CCTA stenosis. Results4187 patients (mean age: 61.9 ​± ​11.7, 63 ​% male) were included. Male sex, African American ethnicity, Hypertension, CAC>400, and smoking were independent predictors of increased LV mass index. During the median 5.1 years of study follow, 265 (6.3 ​%) deaths occurred. Increased LV mass index percentiles were associated with increased risk of ACM. The addition of LV mass index percentiles improved discrimination and reclassification for mortality prediction over a model with age, sex, conventional risk factors, CAC score and CCTA stenosis severity (X2 improvement: 22.68, NRI: 28 ​%, both p ​< ​0.001). ConclusionIn a large sample of patients without known CAD who underwent CCTA, increased LV mass index provided independent and incremental prognostic value for all-cause mortality. Assessment of LV mass by CCTA, considering age and gender distribution, can be utilized clinically to identify patients with high myocardial mass.

High-Resolution Vessel Wall Imaging in Primary CNS Vasculitis: A Case Series

High-resolution vessel wall imaging (HRVWI) is a relatively new technique in which vessel walls can be imaged suppressing the cerebrospinal fluid and blood signals. If there is inflammation of the vessel wall (vasculitis) it will show contrast enhancement. This is the only modality which is available to study vessel walls. All angiography techniques including Magnetic Resonance Angiography(MRA), Contrast computerized tomography angiography (CT -Angiography), and digital subtraction angiography (DSA) shows only the state of the lumen of the blood vessel. Involvement of blood vessels in Central Nervous system (CNS) can occur in systemic vasculitis (like microscopic polyangiitis, Polyarteritis nodosa, etc) where there is evidence of other organ involvement or primary CNS vasculitis (PCNSV) in which only involvement of the brain and spinal cord occurs. PCNSV is a rare disease and till now only the brain biopsy is the gold standard for definitive diagnosis. Brain biopsy is an invasive procedure, not always available, and many patients don’t give consent for the procedure. HRWVI can complement the angiography in the diagnosis of CNS vasculitis, especially PCNSV. Here we describe a case series of 4 cases of CNS vasculitis (3 cases of possible PCNSV and one vasculitic moya- moya syndrome) who had presented with stroke, All had abnormal Cerebrospinal fluid (CSF) and HRVWI showed contrast enhancement of the vessel wall indicating the possibility of vasculitis. In two cases, there was involvement of medium-sized arteries (middle cerebral artery), one patient had unilateral internal carotid artery (ICA) involvement and one had bilateral supra- clinoid stenosis of ICA associated with hyperthyroidism (vasculitic Moyamoya syndrome).

Coronary Artery Vasculitis and Encasement: Multimodality Imaging Findings and Mimics.

Coronary artery vasculitis (CAV) and coronary artery encasement are rarely diagnosed conditions that are important diagnostic considerations, particularly in patients with acute coronary syndrome without traditional cardiovascular risk factors or systemic illness. Vasculitis refers to inflammation of the blood vessel walls, which can be primary or secondary. This process should be distinguished from neoplastic involvement of the coronary arteries, termed coronary artery encasement. Prospective diagnosis of these diseases is challenging, often requiring multidisciplinary workup with careful attention to clinical presentation and multiorgan findings. While CAV and coronary artery encasement can be indistinguishable at coronary CT angiography, certain imaging features help order the differential diagnosis. CAV should be considered when there is smooth wall thickening that is circumferential and/or continuous. A diagnosis of coronary artery encasement is favored when there is irregular or nodular wall thickening that is eccentric to the vessel lumen. Epicardial fat stranding may also appear more extensive compared with CAV. Potential mimics of CAV include atherosclerosis, acute plaque rupture, coronary artery aneurysm, and spontaneous coronary artery dissection. Detection and diagnosis of CAV may help avoid complications related to accelerated atherosclerosis and infarction. Radiologists should be familiar with the range of pathologic conditions that can affect the coronary arteries beyond atherosclerosis as they may be the first to raise such diagnostic possibilities, guiding next steps in patient workup and management. ©RSNA, 2024 Supplemental material is available for this article.

Coronary CT angiography instead of invasive angiography before TAVI: Feasibility and outcomes

AimsConcomitant coronary artery disease (CAD) is frequent in transcatheter aortic valve implantation (TAVI) candidates. Despite societal recommendations of performing invasive coronary angiography (ICA) for coronary assessment in the pre-TAVI diagnostic workup, the prognostic value of ICA and beneficial effect of revascularization in these patients remains unclear.We aimed to determine feasibility and outcomes following a strategy of cardiac CT + coronary CT angiography (cCTA) rather than cardiac CT + ICA before TAVI. Methods and resultsWe performed a single-center, observational cohort study including all patients, without previous coronary intervention, referred to TAVI between April 2020 and November 2021. CAD was assessed by cCTA, and only patients with proximal stenosis >70 %, or left main stenosis >50 %, or cCTA was non-evaluable regarding proximal segments were subsequently referred to ICA.240 patients were included in the study. No adverse effects to pre-cCTA-scan nitroglycerin administration were observed. On cCTA, 92 % of the patients had atheroscerosis. 191 (80 %) patients had cCTA only performed, while 49 (20 %) patients underwent subsequent ICA. During a median (range) follow-up of 15 (Abdel-Wahab et al., 2012; Rapp et al., 2001; Sabbah et al., 2021; Gautier et al., 2011; Sankaramangalam et al., 2017; Otto et al., 2021; Tarantini et al., 2023; Vahanian et al., 2021; Faroux et al., 2019; Ferraro et al., 2020; Patterson et al., 2021; Blanke et al., 2019; Bleakley and Monaghan, 2018; Knuuti et al., 2020; Moss et al., 2017; van den Boogert et al., 2018; Collet et al., 2018; Linde et al., 2020; Schmidt et al., 2018; Hansson et al., 2013 [6–25]) months, no difference in procedural complication rates, mortality rates, or number of unplanned ICA was observed between patients evaluated with only cCTA vs cCTA+ICA. ConclusionsUpfront cCTA instead of ICA for assessment of obstructive CAD in the diagnostic workup of patients with severe aortic stenosis referred to TAVI is feasible, safe, and with similar procedural and clinical outcomes. Randomized studies are warranted to further validate the safety of using CTA rather than ICA for coronary assessment in TAVI candidates.

PERFIL DE PACIENTES SUBMETIDOS A TOMOGRAFIA DE CORONÁRIAS EM UM SERVIÇO DE IMAGEM CARDIOVASCULAR DE SERGIPE

Introduction: Computed tomography angiography (CT angiography) of the coronary arteries can identify coronary artery disease (CAD) in its early stages. CAD is characterized by a narrowing of the arterial lumen due to the accumulation of fatty plaques in its walls. Currently, the gold standard for diagnosis is coronary angiography, an invasive measure that seeks to visualize the arterial lumen. The aim of this study was to characterize an outpatient sample using CT angiography as a diagnostic method. Methodology: This cross-sectional, observational prevalence study was based on data collection at a clinic in the city of Aracaju, where the angiotomography results of 210 patients were analyzed, 115 females and 95 males, tabulated as absolute numbers, percentages and averages. Results: The correlation of gender and age with the presence of luminal reduction showed that men and older individuals had a higher degree of alterations on CT angiography. When assessed by territory, the Left Coronary Trunk (LCT) often showed no luminal reduction, with the Anterior Descending Trunk showing the most alterations. Men present more lesions in the Right Coronary and Anterior Descending. Conclusion: Several factors can influence the incidence of CAD, gender and age being among the most important, as shown by the higher incidence in older men than in women or in younger individuals with luminal reduction.

Circle of Willis and Its Anatomical Relevance

The Circle of Willis is an arterial network located at the base of the brain, formed by the interconnection of the anterior, middle, and posterior cerebral arteries, along with the anterior and posterior communicating arteries. It connects the internal carotid arteries to the vertebral arteries, allowing the distribution of cerebral blood flow. Its significance lies in its ability to offer an alternative pathway in cases of arterial obstruction, helping to prevent cerebral ischemia. However, anatomical variations of this structure are common, and only 20% to 25% of the population has a "complete" or symmetrical configuration. Such variations can influence the risk of cerebrovascular diseases, such as stroke, as they may compromise the efficiency of the compensatory mechanism. These anatomical variations have a direct impact on the diagnosis and treatment of neurological conditions. The integrity of the Circle of Willis can influence the severity of symptoms in cases of ischemic strokes, as well as affect aneurysm formation and its clinical implications. Advances in imaging techniques, such as CT angiography and magnetic resonance imaging, have enabled more accurate diagnoses and the development of more effective treatments for conditions associated with the Circle of Willis, making its anatomical understanding essential for the prevention and management of cerebrovascular diseases.