Unruptured intracranial aneurysm volume change patterns and association with age, sex, location in vascular tree, and common risk factors: a single-centre retrospective study.

INTRODUCTION: Unruptured intracranial aneurysms pose a significant clinical and decision-making dilemma. Increase in dome size is one of the crucial indications for treatment. Almost no data exists as to how aneurysms change in size over time. MATERIAL AND METHODS: 102 patients (76 women) who had a total of 501 CT examinations were included in the study. Inclusion criteria were: at least three CT angiography studies, an observation period of at least three years, or bleeding during the follow-up period. In each study, the volume of each aneurysm was measured at least four times by two experienced neuroradiologists with the use of dedicated tools. Collected data was used to obtain numerical volume change models for each aneurysm. RESULTS: 149 aneurysms were analysed in the study (118 in women) No significant differences in location, size or age of observation were detected between men and women. Median follow-up was 5.64 years (IQR 4.17-7.71) and total aneurysm observation time amounted to 964.59 years. There were 57 branching zone aneurysms (women 46), 44 sidewall aneurysms (women 36), 20 anterior communicating artery aneurysms (women 16), 20 posterior communicating artery aneurysms (women 13), and eight posterior circulation aneurysms (women 7). 78 (52%) aneurysms remained stable (women 59), 24 (16.6%) increased their volume (women 20), and five (3.4%) decreased (women 4). In 42 (28%) cases, we observed non-uniform routes of volume changes over surveillance (women 35). In the last group, analysing the whole period of follow-up, 29 (69%) did not change volume (women 24), 11 (26%) grew (women 10), and two decreased in size (4.8%, women 1). Bifurcation zone aneurysms, lower aspect ratio, lower patient age, and higher initial volume were associated with an increased risk of aneurysm growth. Posterior circulation aneurysms presented the lowest rate of volume increase. CONCLUSIONS: A substantial amount of followed up aneurysms could change volume in a non-uniform way, and an increase in volume may not lead to aneurysm rupture.

Evaluation of coeliac trunk and hepatic artery variations in thoracic CT angiography in patients with congenital heart disease.

INTRODUCTION: Understanding the variations of abdominal vascular structures is important for preventing complications of abdominal surgical procedures for gastrointestinal disease such as necrotizing enterocolitis or others that may arise in patients with congenital cardiac disease. We analysed the coeliac trunk and its branches in children with congenital heart disease to determine whether there is a greater prevalence of associated vascular abnormalities. METHODS: We retrospectively analysed thoracic computed tomography (CT) angiograms performed in our hospital in paediatric patients with congenital heart disease. We documented the anatomical variations observed in abdominal sections in which the coeliac trunk and hepatic arteries were included in the field of view. We used the Uflacker classification to describe anatomical variants of the coeliac trunk, and the Michels classification and its modified version (Hiatt classification) to describe the anatomy of the hepatic artery system. RESULTS: Our study included 178 patients with congenital heart disease. We identified coeliac trunk variants in 10.7% of the patients. Gastrosplenic trunk was to the most prevalent variant, amounting to 5.6% of total cases. We found hepatic artery variations in 19.1% of the patients. According to the Michels classification, the prevalence of accessory left hepatic artery arising from the left gastric artery as 4.5%, compared to 6.7% based on the Hiatt classification. CONCLUSION: The prevalence of coeliac trunk and hepatic artery variations in patients with congenital heart disease was not greater in our study compared to other series in the literature. Clinicians must be vigilant about the variations detected in multislice CT scans to avoid complications resulting from vascular abnormalities, especially in patients who undergo abdominal surgery.

Serum Lipoproteins Are Associated With Coronary Atherosclerosis in Asymptomatic U.S. Adults Without Traditional Risk Factors.

Background: The relationship between atherogenic lipoproteins and subclinical coronary atherosclerosis has not been thoroughly evaluated in low-risk adults. Objectives: The purpose of this study was to assess the association of low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (HDL-C), and apolipoprotein B (apoB) with coronary atherosclerosis in adults without traditional risk factors. Methods: We assessed atherosclerosis on coronary computed tomography angiography among asymptomatic adults in the Miami Heart Study not taking lipid-lowering therapy and without hypertension, diabetes, or active tobacco use. Prevalence of atherosclerosis was evaluated based on serum LDL-C, non-HDL-C, and apoB, and multivariable logistic regression with forward selection was used to assess variables associated with coronary plaque. Results: Among 1,033 adults 40 to 65 years of age, 55.0% were women and 86.3% had estimated 10-year atherosclerotic cardiovascular disease risk <5%. Coronary atherosclerosis prevalence was 35.9% (50.6% in men; 23.8% in women) and 3.4% had ≥1 high-risk plaque feature. Atherosclerosis prevalence increased with LDL-C, ranging from 13.2% in adults with LDL-C <70 mg/dL up to 48.2% with ≥160 mg/dL. Higher LDL-C (adjusted OR [aOR]: 1.13 [95% CI: 1.08-1.18] per 10 mg/dL), age (aOR: 1.43 [95% CI: 1.28-1.60] per 5 years), male sex (aOR: 3.81 [95% CI: 2.86-5.10]), and elevated lipoprotein(a) (aOR: 1.46 [95% CI: 1.01-2.09]) were associated with atherosclerosis. Higher serum non-HDL-C and apoB were similarly associated with atherosclerosis. In adults with optimal risk factors, 21.2% had atherosclerosis with greater prevalence at higher lipoprotein levels. Conclusions: Among asymptomatic middle-aged adults without traditional risk factors, coronary atherosclerosis is common and increasingly prevalent at higher levels of atherogenic lipoproteins. These findings emphasize the importance of lipid-lowering strategies to prevent development and progression of atherosclerosis regardless of risk factors.

Optimizing Surgical Choices of Renal Artery Aneurysm With Sequential Use of "Two-Click AVA" Technique and FlightPlan for Embolization: A Report of Two Cases.

BACKGROUND: Selecting intervention strategies for renal artery aneurysms (RAAs) is challenging especially for those located at the vessel bifurcation. The relationship between the aneurysm and renal branches could not always be accurately viewed from traditional computed tomography angiography (CTA) images. CASE PRESENTATION: This study proposed a new method to investigate the anatomy and affected vessel branches of RAAs using automated software. Two patients with RAAs located at the renal artery bifurcation underwent Cone beam CTA (CBCTA) analysis. We sequentially coupled the "two-click AVA" function of Vessel IQ Xpress (GE Healthcare) with the "vascular tree extraction" function from FlightPlan for Embolization (GE Healthcare) to evaluate the relationship among the main renal artery, vessel branches, and aneurysms. The results showed that one patient had 1 out of 3 branches affected by the aneurysm, whereas the other's branches were all affected. Endovascular repair and open surgery were performed respectively based on the image analysis. Both patients recovered well at follow-up examination. CONCLUSIONS: Based on CBCTA analysis, the combination use of the "two-click AVA" function of VesselIQ Xpress and FlightPlan for Embolization software could assist in aneurysm assessment and intervention choices for RAAs.

A Case Report of Type B Aortic Dissection With Ruptured False Lumen.

Aortic dissection is a critical condition characterized by an intimal tear in the aortic wall, leading to the formation of a false lumen. We present a case of a 54-year-old male with chronic type B aortic dissection and hypertension who presented with acute tearing left back pain. Initial evaluation revealed elevated blood pressure and subtle laboratory abnormalities. Imaging confirmed a Stanford type B aortic dissection with an intramural hematoma and contained rupture of the false lumen. Despite initial stabilization efforts, the patient deteriorated rapidly and succumbed. This case highlights the critical importance of early diagnosis.

Association study of NAFLD with pericoronary adipose tissue and pericardial adipose tissue: Diagnosis of stable CAD patients with NAFLD based on radiomic features.

BACKGROUND AND AIM: Nonalcoholic fatty liver disease (NAFLD) is prone to complicated cardiovascular disease, and we aimed to identify patients with NAFLD who are prone to developing stable coronary artery disease (CAD). METHODS AND RESULTS: We retrospectively recruited adults who underwent coronary computed tomography angiography (CTA). A total of 127 NAFLD patients and 127 non-NAFLD patients were included in this study. Clinical features and imaging parameters were analysed, mainly including pericardial adipose tissue (PAT), pericoronary adipose tissue (PCAT), and radiomic features of 6792 PCATs. The inflammatory associations of NAFLD patients with PAT and PCAT were analysed. Clinical features (model 1), CTA parameters (model 2), the radscore (model 3), and a composite model (model 4) were constructed to identify patients with NAFLD with stable CAD. The presence of NAFLD resulted in a greater inflammatory involvement in all three coronary arteries (all P < 0.01) and was associated with increased PAT volume (r = 0.178**, P < 0.05). In the presence of NAFLD, the mean CT value of the PAT was significantly correlated with the fat attenuation index (FAI) in all three vessels and had the strongest correlation with the RCA FAI (r = 0.55, p < 0.001). A total of 9 radiomic features were screened by LASSO regression to calculate radiomic scores. In the model comparison, model 4 had the best performance of all models (AUC 0.914 [0.863-0.965]) and the highest overall diagnostic value of the model (sensitivity: 0.814, specificity: 0.941). CONCLUSIONS: NAFLD correlates with PAT volume and PCAT inflammation. Furthermore, combining clinical features, CTA parameters, and radiomic scores can improve the efficiency of early diagnosis of stable CAD in patients with NAFLD.

Multi-omics analysis of overexpressed tumor-associated proteins: gene expression, immunopeptide presentation, and antibody response in oropharyngeal squamous cell carcinoma, with a focus on cancer-testis antigens.

Introduction: The human leukocyte antigen complex (HLA) is essential for inducing specific immune responses to cancer by presenting tumor-associated peptides (TAP) to T cells. Overexpressed tumor associated antigens, mainly cancer-testis antigens (CTA), are outlined as essential targets for immunotherapy in oropharyngeal squamous cell carcinoma (OPSCC). This study assessed the degree to which presentation, gene expression, and antibody response (AR) of TAP, mainly CTA, are correlated in OPSCC patients to evaluate their potential as immunotherapy targets. Materials and methods: Snap-frozen tumor (NLigand/RNA=40), healthy mucosa (NRNA=6), and healthy tonsils (NLigand=5) samples were obtained. RNA-Seq was performed using Illumina HiSeq 2500/NovaSeq 6000 and whole exome sequencing (WES) utilizing NextSeq500. HLA ligands were isolated from tumor tissue using immunoaffinity purification, UHPLC, and analyzed by tandem MS. Antibodies were measured in serum (NAb=27) utilizing the KREX™ CT262 protein array. Data analysis focused on 312 proteins (KREX™ CT262 panel + overexpressed self-proteins). Results: 183 and 94 of HLA class I and II TAP were identified by comparative profiling with healthy tonsils. Genes from 26 TAP were overexpressed in tumors compared to healthy mucosa (LFC>1; FDR<0.05). Low concordance (r=0.25; p<0.0001) was found between upregulated mRNA and class I TAP. The specific mode of correlation of TAP was found to be dependent on clinical parameters. A lack of correlation was observed both between mRNA and class II TAP, as well as between class II tumor-unique TAP (TAP-U) presentation and antibody response (AR) levels. Discussion: This study demonstrates that focusing exclusively on gene transcript levels fails to capture the full extent of TAP presentation in OPSCC. Furthermore, our findings reveal that although CTA are presented at relatively low levels, a few CTA TAP-U show potential as targets for immunotherapy.

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

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

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

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

Epidemiology of headache presentations to United States emergency departments from 2016 to 2023.

INTRODUCTION: Headaches are a common condition seen in the Emergency Department (ED), with numerous trials focused on improving care for these patients. However, there is limited recent large-scale, robust data available on the incidence, admission rates, evaluation, and treatment in the ED setting. METHODS: This was a cross-sectional study of ED presentations for headache from 1/1/2016 to 12/31/2023 using the Epic Cosmos national database. All ED visits with headache-relevant ICD-10 coding were included. Outcomes included percentage of total ED visits, admission rates, computed tomography (CT) brain imaging, lumbar puncture (LP) performance, and medication administration. Medications were analyzed by class (NSAIDs, acetaminophen, dopamine antagonists, diphenhydramine, opioids, intravenous fluids, caffeine, and magnesium sulfate). Subgroup analyses were performed by specific types of dopamine antagonists. RESULTS: Of 188,482,644 ED encounters, 6,007,090 (3.2%) were due to headache. Of these, 246,082 (4.1%) were admitted. Nearly half (46.6%) of patients received at least one CT. Rates of CT head without contrast increased from 38.2% to 47.9% over time, while rates of CT angiography rose from 2.8% to 10.2%. 1.4% of all patients received an LP, with rates decreasing from 1.8% to 1.1% over time. The most common medication was NSAIDs (45.3%), followed by dopamine antagonists (44.8%), diphenhydramine (38.1%), acetaminophen (24.8%), opioids (16.3%), magnesium sulfate (0.2%), and caffeine (0.1%). 50.8% of patients received intravenous fluids. Rates of opioids declined over time, while dopamine antagonists, acetaminophen, and intravenous fluid administration increased. CONCLUSION: Headaches represent a common reason for ED presentation, with approximately 4% of patients being admitted. Imaging is frequently performed, with rises in CT without contrast and CT angiography rates over time, while LP rates have been declining. NSAIDs remain the most common medication given, with opioids declining over time while non-opioid agents such as dopamine antagonists have increased. These findings can help inform health policy initiatives, such as those focused on radiologic imaging and evidence-based medication administration.

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

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

Prevalence of pelvic CT angiography (CTA) and angiographic embolization in geriatric patients with pelvic ring fractures presenting to two level I trauma centers.

OBJECTIVES: Hemorrhage in osteoporotic pelvic ring fractures is a rare, but serious complication. Most bleeding comes from the bone or venous plexuses, but arterial injury does occur. The purpose of this study was to characterize a large geriatric pelvic fracture cohort and determine the prevalence of pelvic CT angiography (CTA) and subsequent need for arterial embolization. METHODS: A cohort of geriatric pelvic fracture patients at two level 1 trauma centers was reviewed. Many epidemiologic and patient factors were collected for cohort characterization. The primary outcome was if patients underwent a CTA of the pelvis and subsequently underwent arterial embolization. RESULTS: There were 457 patients included and mean age was 83.1 years (range 65-100). Most patients had a low energy mechanism (91.4 %). In-hospital mortality was recorded for 30 cases (6.6 %). Of these deaths, two received a pelvic CTA and two had an embolization procedure. Pelvic CTA was performed on 33 patients (7.2 %). Fourteen patients (3.0 %) had an arterial embolization procedure. A high energy mechanism of injury was associated with receiving a pelvic CTA (p = 0.0067). Mechanism of injury was not associated with undergoing an embolization procedure (p = 0.685). DISCUSSION: In the geriatric population, even patients with stable pelvic fractures can present with life-threatening arterial bleeding. A non-insignificant percentage of patients will require CTA for suspected bleeding (7.2 %) and embolization to treat confirmed arterial bleeding (3.0 %). CONCLUSIONS: Bleeding events in geriatric pelvic ring injuries is a previously under researched area of orthopedic trauma. Further research is needed to elucidate the exact pathomechanisms of arterial injury and what patients or injury patterns are most significantly associated. Specifically, larger cohort sizes and evaluating our existing cohort with different injury classification systems may yield useful results.

1 Patient With Single Coronary Artery, Giant Coronary Artery Aneurysm, Contained Rupture, and Fistula.

Single coronary artery, giant coronary artery aneurysm, and coronary cameral fistula are rare congenital anomalies, and can cause a range of presentations. To our knowledge, this is the first reported case of all 3 entities occurring simultaneously in 1 patient, with largely unknown implications. Multimodal imaging was essential in prompt diagnosis and management.

Posttraumatic Renal Artery-Inferior Vena Cava Fistula-Induced High-Output Cardiac Failure: A Case Study.

High-output cardiac failure is a less prevalent form of heart failure. Most patients with heart failure are typically categorized as having either systolic or diastolic dysfunction with elevated systemic vascular resistance. Individuals with high-output cardiac failure exhibit normal cardiac function and decreased systemic vascular resistance. This reduction may stem from diffuse arteriolar dilation or potential bypass of arterioles and capillary beds, prompting the activation of neurohormones. This case report details the diagnosis and treatment of an unusual etiology of high-output cardiac failure involving an arteriovenous fistula connecting the renal artery to the inferior vena cava and right common iliac vessels, resulting in a left-to-right shunt in a 50-year-old male patient. The report explores the etiology, pathophysiology, and clinical presentation of high-output heart failure, emphasizing the crucial role of radiology in interprofessional teams.

Abbreviated MRI in the evaluation of dizziness: report turnaround times and impact on length of stay compared to CT, CTA, and conventional MRI.

PURPOSE: Neuroimaging is often used in the emergency department (ED) to evaluate for posterior circulation strokes in patients with dizziness, commonly with CT/CTA due to speed and availability. Although MRI offers more sensitive evaluation, it is less commonly used, in part due to slower turnaround times. We assess the potential for abbreviated MRI to improve reporting times and impact on length of stay (LOS) compared to conventional MRI (as well as CT/CTA) in the evaluation of acute dizziness. MATERIALS AND METHODS: We performed a retrospective analysis of length of stay via LASSO regression for patients presenting to the ED with dizziness and discharged directly from the ED over 4 years (1/1/2018-12/31/2021), controlling for numerous patient-level and logistical factors. We additionally assessed turnaround time between order and final report for various imaging modalities. RESULTS: 14,204 patients were included in our analysis. Turnaround time for abbreviated MRI was significantly lower than for conventional MRI (4.40 h vs. 6.14 h, p < 0.001) with decreased impact on LOS (0.58 h vs. 2.02 h). Abbreviated MRI studies had longer turnaround time (4.40 h vs. 1.41 h, p < 0.001) and was associated with greater impact on ED LOS than non-contrast CT head (0.58 h vs. 0.00 h), however there was no significant difference in turnaround time compared to CTA head and neck (4.40 h vs. 3.86 h, p = 0.06) with similar effect on LOS (0.58 h vs. 0.53 h). Ordering both CTA and conventional MRI was associated with a greater-than-linear increase in LOS (additional 0.37 h); the same trend was not seen combining CTA and abbreviated MRI (additional 0.00 h). CONCLUSIONS: In the acute settings where MRI is available, abbreviated MRI protocols may improve turnaround times and LOS compared to conventional MRI protocols. Since recent guidelines recommend MRI over CT in the evaluation of dizziness, implementation of abbreviated MRI protocols has the potential to facilitate rapid access to preferred imaging, while minimizing impact on ED workflows.

CTA Imaging of Peripheral Arterial Injuries.

Traumatic vascular injuries consist of direct or indirect damage to arteries and/or veins and account for 3% of all traumatic injuries. Typical consequences are hemorrhage and ischemia. Vascular injuries of the extremities can occur isolated or in association with major trauma and other organ injuries. They account for 1-2% of patients admitted to emergency departments and for approximately 50% of all arterial injuries. Lower extremities are more frequently injured than upper ones in the adult population. The outcome of vascular injuries is strictly correlated to the environment and the time background. Treatment can be challenging, notably in polytrauma because of the dilemma of which injury should be prioritized, and treatment delay can cause disability or even death, especially for limb vascular injury. Our purposes are to discuss the role of computed tomography angiography (CTA) in the diagnosis of vascular trauma and its optimized protocol to achieve a definitive diagnosis and to assess the radiological signs of vascular injuries and the possible pitfalls.

The impact of different imaging modalities in diagnosis and management of patient with dural arteriovenous fistula: A rare case report.

In vascular neurosurgery, dural arteriovenous fistulas (DAVFs) are a difficult, challenging condition whose natural history and therapy are still debated. This case report presented a 30-year-old male patient who experienced intermittent headaches for two months, along with gradual weakness in all four limbs, resulting in quadriplegia. Magnetic resonance imaging (MRI), computed tomography (CT), and digital subtraction angiography (DSA) played a significant role in the diagnosis of the patient, in which the final diagnosis was vascular myelopathy due to Dural arteriovenous fistula (DAVF). A successful embolization procedure of arteriovenous fistula using balloon-assisted liquid embolic agents, through branches of the right occipital artery was performed, resulting in complete obliteration of the fistula. In order to improve the neurovascular symptoms that had previously been reported, the patient was effectively undergoing rehabilitation, with notable progress.

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

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

Prospective ECG-gated High-Pitch Photon-Counting CT Angiography: Evaluation of measurement accuracy for aortic annulus sizing in TAVR planning.

PURPOSE: In planning transcatheter aortic valve replacement (TAVR), retrospective cardiac spiral-CT is recommended to measure aortic annulus with subsequent CT-angiography (CTA) to evaluate access routes. Photon-counting detector (PCD)-CT enables to assess the aortic annulus in desired cardiac phases, using prospective ECG-gated high-pitch CTA. The aim of this study was to evaluate the measurement accuracy of aortic annulus using prospective ECG-gated high-pitch CTA against retrospective spiral-CT reference. METHOD: Thirty patients underwent cardiac spiral-CT and prospective ECG-gated (30% R-R on aortic valve level) high-pitch CTA. Using propensity score matching, another 30 patients were identified whose CTA was performed using high-pitch mode without ECG-synchronization. Two investigators measured annular diameter, perimeter, and area on cardiac spiral-CT and high-pitch CTA. RESULTS: The aortic valve was imaged in systole in 90 % of prospective ECG-gated CTA cases but only 50 % of non-ECG-gated CTA cases (p = 0.002). There was a strong correlation (r ≥ 0.94) without significant differences (p ≥ 0.09) between cardiac spiral-CT and prospective ECG-gated high-pitch CTA for all annulus measurements. In contrast, significant differences were found in annular short-axis diameter and area between cardiac spiral-CT and non-ECG-gated high-pitch CTA (p ≤ 0.03). Furthermore, prospective ECG-gated high-pitch CTA showed significantly reduced radiation exposure compared with cardiac spiral-CT (CTDI 4.52 vs. 24.10 mGy; p < 0.001). CONCLUSION: PCD-CT-based prospective ECG-gated high-pitch scans with targeted systolic acquisition at the level of the aortic valve can simultaneously visualize TAVR access routes and accurately measure systolic annulus size. This approach could aid in optimizing protocols to achieve lower radiation doses in the growing population of younger, low-risk TAVR patients.

Polyenergetic reconstruction mitigates streak artifacts by dual source imaging in chest photon counting detector computed tomography.

OBJECTIVE: This study aims to assess the efficacy of polyenergetic reconstruction methods in reducing streak artifacts caused by dual source imaging in Photon Counting Detector Computed Tomography (PCD-CT) imaging, thereby improving image quality and diagnostic accuracy. METHODS: A retrospective cohort study was conducted, involving 50 patients who underwent chest Computed Tomography Angiography with PCD-CT, focusing on those with streak artifacts. Quantitative and qualitative analyses were performed on images reconstructed using monoenergetic and polyenergetic techniques. Quantitative evaluations measured the attenuation of tracheal air density in regions affected by streak artifacts, while qualitative assessments employed a modified Likert scale to rate image quality. Statistical analyses included Wilcoxon's signed-rank tests and Spearman's correlation, alongside assessments of inter-rater reliability. RESULTS: There was significantly lower attenuation of tracheal air density on the polyenergetic reconstructions (Median - 1010 ± 62 HU vs -930 ± 110 HU; P < 0.001), and significantly decreased variation on the polyenergetic reconstructions (Median 65.2 ± 79.5 HU vs 38.8 ± 33.9 HU; P < 0.001). The median modified-Likert scale were significantly better for the polyenergetic reconstructions (median modified-Likert 4 ± 0.5 vs 2.5 ± 1; P < 0.001). The inter-rater agreement was substantial and not significantly different between reconstructions (Gwet's ACPolyenergetic = 0.78 vs Gwet's ACVMI = 0.775). CONCLUSION: Polyenergetic reconstruction significantly mitigates streak artifacts in PCD-CT imaging, enhancing quantitative and qualitative image quality. This advancement addresses a known limitation of current PCD-CT reconstruction techniques, offering a promising approach to improving diagnostic reliability and accuracy in clinical practice. We demonstrate that future software implementations can resolve this artifact.