Multidetector computed tomographic angiography of the cardiovascular system

Verification of a simplified aneurysm dimensionless flow parameter to predict intracranial aneurysm rupture status

OBJECTIVES

Aneurysm number (An) is a novel prediction tool utilizing parameters of pulsatility index (PI) and aneurysm geometry. An has been shown to have the potential to differentiate intracranial aneurysm (IA) rupture status. The objective of this study is to investigate the feasibility and accuracy of An for IA rupture status prediction using Australian based clinical data.

METHODS

A retrospective study was conducted across three tertiary referral hospitals between November 2017 and November 2020 and all saccular IAs with known rupture status were included. Two sets of An values were calculated based on two sets of PI values previously reported in the literature.

RESULTS

Five hundred and four IA cases were included in this study. The results demonstrated no significant difference between ruptured and unruptured status when using An ≥1 as the discriminator. Further analysis showed no strong correlation between An and IA subtypes. The area under the curve (AUC) indicated poor performance in predicting rupture status (AUC1 = 0.55 and AUC2 = 0.56).

CONCLUSIONS

This study does not support An ≥1 as a reliable parameter to predict the rupture status of IAs based on a retrospective cohort. Although the concept of An is supported by hemodynamic aneurysm theory, further research is needed before it can be applied in the clinical setting.

ADVANCES IN KNOWLEDGE

This study demonstrates that the novel prediction tool, An, proposed in 2020 is not reliable and that further research of this hemodynamic model is needed before it can be incorporated into the prediction of IA rupture status.

Preprocedural Planning of Left Atrial Appendage Occlusion: A Review of the Use of Additive Manufacturing

Stroke is a significant public health problem, with non-valvular atrial fibrillation (NVAF) being one of its main causes. This cardiovascular arrhythmia predisposes to the production of intracardiac thrombi, mostly formed in the left atrial appendage (LAA). When there are contraindications to treatment with oral anticoagulants, another therapeutic option to reduce the possibility of thrombus formation in the LAA is the implantation of an occlusion device by cardiac catheterization. The effectiveness of LAA occlusion is dependent on accurate preprocedural device sizing and proper device positioning at the LAA ostium, to ensure sufficient device anchoring and avoid peri-device leaks. Additive manufacturing, commonly known as three-dimensional printing (3DP), of LAA models is beginning to emerge in the scientific literature to address these challenges through procedural simulation. This review aims at clarifying the impact of 3DP on preprocedural planning of LAA occlusion, specifically in the training of cardiac surgeons and in the assessment of the perfect adjustment between the LAA and the biomedical implant.

Computed Tomography: State-of-the-Art Advancements in Musculoskeletal Imaging

ABSTRACT

Although musculoskeletal magnetic resonance imaging (MRI) plays a dominant role in characterizing abnormalities, novel computed tomography (CT) techniques have found an emerging niche in several scenarios such as trauma, gout, and the characterization of pathologic biomechanical states during motion and weight-bearing. Recent developments and advancements in the field of musculoskeletal CT include 4-dimensional, cone-beam (CB), and dual-energy (DE) CT. Four-dimensional CT has the potential to quantify biomechanical derangements of peripheral joints in different joint positions to diagnose and characterize patellofemoral instability, scapholunate ligamentous injuries, and syndesmotic injuries. Cone-beam CT provides an opportunity to image peripheral joints during weight-bearing, augmenting the diagnosis and characterization of disease processes. Emerging CBCT technologies improved spatial resolution for osseous microstructures in the quantitative analysis of osteoarthritis-related subchondral bone changes, trauma, and fracture healing. Dual-energy CT-based material decomposition visualizes and quantifies monosodium urate crystals in gout, bone marrow edema in traumatic and nontraumatic fractures, and neoplastic disease. Recently, DE techniques have been applied to CBCT, contributing to increased image quality in contrast-enhanced arthrography, bone densitometry, and bone marrow imaging. This review describes 4-dimensional CT, CBCT, and DECT advances, current logistical limitations, and prospects for each technique.

The utility of ultrasound and computed tomography in the assessment of carotid artery plaque vulnerability-A mini review

As the burden of cardiovascular and cerebrovascular events continues to increase, emerging evidence supports the concept of plaque vulnerability as a strong marker of plaque rupture, and embolization. Qualitative assessment of the plaque can identify the degree of plaque instability. Ultrasound and computed tomography (CT) have emerged as safe and accurate techniques for the assessment of plaque vulnerability. Plaque features including but not limited to surface ulceration, large lipid core, thin fibrous cap (FC), intraplaque neovascularization and hemorrhage can be assessed and are linked to plaque instability.

Comparison of Various Modalities Utilized for Preoperative Planning in Microsurgical Reconstructive Surgery

BACKGROUND

 The benefits of preoperative perforator imaging for microsurgical reconstruction have been well established in the literature.

METHODS

 An extensive literature review was performed to determine the most commonly used modalities, and their applicability, advantages and disadvantages.

RESULTS

 The review demonstrated varioius findings including decreases in operative time and cost with the use of CT angiography to identification of perforators for inclusion in flap design with hand-held Doppler ultrasound. Modalities like MR angiography offer alternatives for patients with contrast allergies or renal dysfunction while maintaining a high level of clarity and fidelity. Although the use of conventional angiography has decreased due to the availability of less invasive alternatives, it continues to serve a role in the preoperative evaluation of patients for lower extremity reconstruction. Duplex ultrasonography has been of great interest recently as an inexpensive, risk free, and extraordinarily accurate diagnostic tool. Emerging technologies such as indocyanine green fluorescence angiography and dynamic infrared thermography provide real-time information about tissue vascularity and perfusion without requiring radiation exposure.

CONCLUSION

 This article presents an in-depth review of the various imaging modalities available to reconstructive surgeons and includes hand held Doppler ultrasound, CT angiography, MR angiography, conventional angiography, duplex ultrasonography, Indocyanine Green Fluorescence Angiography and Dynamic Infrared Thermography.

Popliteal Artery Branching Variations: A Study on Multidetector CT Angiography

Determining the branching pattern of the popliteal artery (PA) is an important step in planning some radiological and surgical procedures. The aim of this study was to investigate the course and morphology of the terminal branches of the popliteal artery using multidetector computed tomography (MDCT) angiography, and also to determine possible role gender in branching pattern. Three-hundred forty lower extremity MDCT angiography images for 170 patients (118 M, 52 F), who were between 20–80 years old, were examined. Popliteal artery branching types were grouped as percentage incidences. TPT diameters and lengths in Type IA extremities were compared based on gender and right or left side. Anterior tibial artery (ATA), posterior tibial artery (PTA) and peroneal artery dominance rates were calculated. 5000 times measurement data was mixed so that the cascade mean filter values were calculated for the right and left TPT length each time. It was observed that Type IA was the most common branching pattern (89.4%). The variational pattern incidence was 10.6% and the most common category was Type III (4.1%). The most common pattern was Type IB (3.2%). Variational pattern was 2 times more prevalent in females when compared to the males. The mean TPT diameter was 4.5 mm (2.7–7.3 mm) and there was no difference based on gender and the right-left side. The most common dominant artery for the right and left legs was PTA in both genders. The cut-off values calculated for the right and left TPT independent of gender were 31.30 ± 2.40 and 28.36 ± 2.58, respectively. Three new subtypes were identified as short (S ≤ 2 cm), standard (N = 2–4 cm) and long (L ≥ 4 cm) in Type IA, since it is in a wide variational range although it is a typical PA branching pattern.

Colonic hypoperfusion following ligation of the inferior mesenteric artery in rectosigmoid colon cancer patients

Purpose

Colon perfusion status is one of the most important factors for the determination of postoperative anastomotic complications. Colonic hypoperfusion can be induced by inferior mesenteric artery (IMA) ligation in some patients. This study aimed to evaluate atherosclerotic risk assessment and vascular parameters of CT angiography as predictors of colonic hypoperfusion.

Methods

This prospective study was conducted at a tertiary referral hospital and included 46 rectosigmoid colon cancer patients undergoing laparoscopic anterior resection between August 2013 to July 2014. Atherosclerotic risk scores were assessed using the Framingham cardiovascular risk score system. The IMA length, branching pattern, atherosclerotic calcification, and intermesenteric artery and mesenteric vascular diameters were evaluated using CT angiography. Mesenteric marginal artery pressures were measured before and after IMA clamping. The mean arterial pressure (MAP) index was calculated by dividing the mesenteric marginal MAP into the systemic MAP to determine the mesenteric hypoperfusion status after IMA clamping. A critically low MAP index was defined as <0.4.

Results

Critically low MAP index (<0.4) was observed in 6 cases (13.0%) after IMA clamping. Atherosclerotic calcification of the IMA and superior mesenteric artery occurred in 11 (23.9%) and 5 patients (10.9%), respectively. Low MAP index was associated with high atherosclerotic risk score and short IMA length, rather than atherosclerotic calcification and other vascular parameters of the major mesenteric arteries. Multivariate analysis indicated that high atherosclerotic risk and short IMA length were independent predictors of critically low MAP index.

Conclusion

Atherosclerotic risk assessment and IMA length were useful predictors of the mesenteric hypoperfusion status following IMA ligation during laparoscopic rectosigmoid colon surgery.

Spontaneous dissection of the celiac artery in the young: a case report and systematic review of the literature

INTRODUCTION

The spontaneous isolated celiac artery dissection (siCAD) represents a challenging cause of abdominal pain and complete information regarding incidence, etiology and risk factors in the young is still lacking. In this study, we report a case of siCAD occurred in a young woman and we systematically searched for information on siCADs in literature databases.

METHODS

PubMed/Embase and Cochrane were searched for, using the following terms: Isolated celiac trunk dissection, isolated celiac artery dissection, celiac artery dissection, celiac trunk dissection, spontaneous isolated visceral artery dissection, spontaneous isolated dissection of visceral arteries, isolated celiac artery dissection in the young, isolated celiac trunk dissection in the young. Patients were included if they were younger than 50 years, if they had a spontaneous etiology and a selective involvement of the celiac artery (with or without involvement of its branches).

RESULTS

180 studies were found, and 18 remained after screening. Twenty-one patients (male = 19, female = 2) with siCADs were included. Mean age was 44.71 ± 3.61 years. Hypertension was the most prevalent comorbidity. All patients presented with abdominal pain, more often located in the epigastrium (n = 11). Almost all patients underwent CT to confirm the diagnosis. A conservative treatment was adopted in 13 patients while an invasive approach was adopted in 8 patients (endovascular approach in 7).

DISCUSSION

siCADs represent a rare but important cause of vascular dissection in the young. Uncomplicated cases can be safely treated with conservative strategies. The surgical or endovascular repair is indicated when dissections complicate or symptoms persist despite an adequate conservative treatment.

Correlates of pericardial adipose tissue volume using multidetector CT scanning in cardiac patients in China

BACKGROUND

Pericardial adipose tissue (PAT) is an emerging cardiovascular risk factor, yet much less is understood about PAT volume in Chinese adults, especially in relation to physical activity. The study explores associations between demographic and clinical variables and PAT volume, using multidetector computed tomography (MDCT) scanning in China. We also examined the relationship between PAT volume and coronary artery disease (CAD).

METHODS

An observational, correlational study design was used. Chinese (n=163) attended a study visit and underwent MDCT scanning between September 2014 and December 2015.

RESULTS

Participants were 48.5% male and had a mean age of 60.6 (SD 9.4) years. PAT volume was higher (p=0.001) in males than in females. PAT volume was correlated with age (r=0.388, p=0.001), systolic blood pressure (r=0.205, p=0.009), body mass index (r=0.466, p=0.001), high-density cholesterol (r=-0.282, p=0.001), low-density cholesterol (r=0.177, p=0.024), and triglycerides (r=0.248, p=0.001). Both moderate intensity physical activity energy consumption (r=-0.363, p=0.001) and total physical activity (r=-0.290, p=0.001) had inverse relationships with PAT volume. Total sedentary energy consumption was positively related to PAT volume (r=0.266, p=0.001). Multiple regression revealed that age, male gender, BMI, LDL-C and total physical activity energy consumption were significant predictors of PAT volume (R²=0.465). The relationship between PAT volume and CAD was found to be significant in the adjusted models.

CONCLUSIONS

Age, male gender, BMI, LDL-C and total physical activity energy consumption were significant predictors of PAT volume, and PAT volume itself is a predictor of CAD.

Analysis of renal artery morphometery in adults: A study conducted by using Multidetector computed Tomography Angiography

Objective:

To determine a reference range of renal artery measurements by using Multidetector Computed Tomography (MDCT) angiography and to find association of renal artery measurements with side of artery, gender and age.

Method:

Two hundred and fifty study participants without renal artery disease who werepresented to Radiology Department, Ziauddin Hospital, Karachi, from November, 2016 to April, 2017 were included in this study. Main renal artery measurements were taken on Multidetector computed angiography and variation with side, gender and age were analyzed. Statistical analysis was done on Statistical Package for Social Sciences (SPSS) version 20. Independent sample T test, one way ANOVA and Pearson’s correlation analysis were applied. P-value of < 0.05 was considered significant.

Results:

A significance difference (p=0.001) was seen between mean right renal artery (diameter 6.66 ± 0.39 mm; length 44.69 ± 2.48 mm) and left renal artery (diameter 6.79 ± 0.36; length 35.10 ± 2.86 mm). Females found to have smaller mean diameter and length of renal arteries than males. However, a weak negative correlation was seen between mean renal artery diameter and age (right r= -0.158, p=0.0121; left r= -0.017, p= 0.708).

Conclusion:

The mean diameter and mean length were found to be significantly different between right and left main renal artery and between males and females. A significant weak negative correlation was observed between renal artery diameter and age.

Fully automated classification of bone marrow infiltration in low-dose CT of patients with multiple myeloma based on probabilistic density model and supervised learning

This paper presents a fully automated method for the identification of bone marrow infiltration in femurs in low-dose CT of patients with multiple myeloma. We automatically find the femurs and the bone marrow within them. In the next step, we create a probabilistic, spatially dependent density model of normal tissue. At test time, we detect unexpectedly high density voxels which may be related to bone marrow infiltration, as outliers to this model. Based on a set of global, aggregated features representing all detections from one femur, we classify the subjects as being either healthy or not. This method was validated on a dataset of 127 subjects with ground truth created from a consensus of two expert radiologists, obtaining an AUC of 0.996 for the task of distinguishing healthy controls and patients with bone marrow infiltration. To the best of our knowledge, no other automatic image-based method for this task has been published before.

How to save a life during a clinic visit for erectile dysfunction by modifying cardiovascular risk factors

Erectile dysfunction (ED) is an early marker for systemic atherosclerosis and is a predictor for coronary artery disease and cardiac events. The aim of this paper is to convey the importance of addressing cardiovascular risk factors in patients with ED and to inform urologists as well as other physicians who are not specialized in cardiology how to carry out a basic cardiovascular evaluation, including history, physical examination and objective data. We review the evidence and pathophysiology linking ED to cardiovascular disease, and then describe how to carry out a basic cardiovascular evaluation. We present data from the literature showing that appropriate use of lifestyle modifications and medical therapy has a positive effect on mortality, on numerous cardiovascular end points and on ED. Suggestions of when to refer the ED patient to an internist or cardiologist are provided. Identifying and treating cardiovascular risk factors may not only benefit the patient's ED, but it might also save the patient's life.