Customizable tubular model for n-furcating blood vessels and its application to 3D reconstruction of the cerebrovascular system

Understanding the 3D cerebral vascular network is one of the pressing issues impacting the diagnostics of various systemic disorders and is helpful in clinical therapeutic strategies. Unfortunately, the existing software in the radiological workstation does not meet the expectations of radiologists who require a computerized system for detailed, quantitative analysis of the human cerebrovascular system in 3D and a standardized geometric description of its components. In this study, we show a method that uses 3D image data from magnetic resonance imaging with contrast to create a geometrical reconstruction of the vessels and a parametric description of the reconstructed segments of the vessels. First, the method isolates the vascular system using controlled morphological growing and performs skeleton extraction and optimization. Then, around the optimized skeleton branches, it creates tubular objects optimized for quality and accuracy of matching with the originally isolated vascular data. Finally, it optimizes the joints on n-furcating vessel segments. As a result, the algorithm gives a complete description of shape, position in space, position relative to other segments, and other anatomical structures of each cerebrovascular system segment. Our method is highly customizable and in principle allows reconstructing vascular structures from any 2D or 3D data. The algorithm solves shortcomings of currently available methods including failures to reconstruct the vessel mesh in the proximity of junctions and is free of mesh collisions in high curvature vessels. It also introduces a number of optimizations in the vessel skeletonization leading to a more smooth and more accurate model of the vessel network. We have tested the method on 20 datasets from the public magnetic resonance angiography image database and show that the method allows for repeatable and robust segmentation of the vessel network and allows to compute vascular lateralization indices. Graphical abstract: [Figure not available: see fulltext.]</p

Anatomy of the cardiac chambers: A review of the left ventricle

Background: The left ventricle is built to carry out its function as a powerful pump. To detail recent findings of anatomical variants associated with the left ventricular compartment, we will first review the external and general features, followed by the internal features and subsequently, the standard variants that can exist within this chamber of the heart. Methods: This literature review seeks to collate and discuss peer-reviewed articles on the anatomy of the left ventricle. Results: The left ventricle has many unique features including walls that are thicker than those of the right ventricle, an overlap of its inlet and outlet portions, and the hinge of the leaflets of the mitral valve that are oriented cranially relative to those of the tricuspid valve. Conclusion: While the left ventricle shares many characteristics with that of the right ventricle, the unique features may contribute to cardiac pathology and can also be used to the surgeon's advantage in treating disease

Cross-sectional area of the femoral vein varies with leg position and distance from the inguinal ligament

<div><p>Purpose</p><p>The risk of complications associated with femoral venous catheterization could be potentially reduced if the procedure was performed at the location where the cross-sectional area (CSA) of the vessel is the largest. The diameter of the femoral vein depends on leg position as well as the distance from the inguinal ligament. We determined the CSA of the right femoral vein in three different leg positions at two distances from the inguinal ligament.</p><p>Subjects and methods</p><p>Informed consent was given by 205 healthy volunteers aged 19–39 years, mean: 23±3 years (108 women, 97 men). Ultrasonographic examinations were performed using a linear 14-MHz transducer with CSA measurements in three leg positions: abduction, abduction+external rotation, abduction+external rotation+90° knee flexion/frog-leg position; at levels 20 mm caudally to the inguinal ligament, and 20 mm caudally to the inguinal crease.</p><p>Results</p><p>We found significant differences in mean values of CSA in three leg positions regardless of the measurement level. The largest mean CSA (114 mm²±35 mm²) was found at the proximal level in the frog-leg position. There was a significant association of the CSA with sex and height. The CSA in males was greater than in females in all leg positions at the level of 20 mm caudally to the inguinal crease, while 20 mm caudally to the inguinal ligament the CSA was larger in females. The CSA of 25% of the femoral vein was smaller than 45.0 mm² at the proximal level, and 31.5 mm² at the distal level, which refers to diameters of 5.3 mm, and 4.5 mm, respectively.</p><p>Conclusions</p><p>The cross-sectional area of the femoral vein is the largest in the frog-leg position, and depends on gender.</p></div

Leg position: Abduction + external rotation + 90° knee flexion/frog-leg.

<p>Leg position: Abduction + external rotation + 90° knee flexion/frog-leg.</p

The mean values, standard deviation, and quartile values for the cross-sectional area (CSA) of the right femoral vein in leg positions 1, 3, 4, and 6 (males and females combined).

<p>The mean values, standard deviation, and quartile values for the cross-sectional area (CSA) of the right femoral vein in leg positions 1, 3, 4, and 6 (males and females combined).</p

Demographic data of the studied participants included in the analysis.

<p>Demographic data of the studied participants included in the analysis.</p

The cross-sectional area [mm²] of the right femoral vein in males and females at the proximal and distal levels in different leg positions.

<p>The cross-sectional area [mm²] of the right femoral vein in males and females at the proximal and distal levels in different leg positions.</p