Description and Anatomy of the Human Body - Essay Example

Axial plane: The first image is an axial plane of the Thorax. The axial or transverse plane cuts the body parallel to the ground into top and bottom halves. The plane is useful in studying the relations between cardiovascular structures by analyzing images at consecutive levels. It is a CT scanned image that uses X-Rays in a complicated way. Thorax: The area of the body located between the neck and the abdomen that contains the lungs, the heart and a portion of the aorta. The walls of the thorax are supported by the dorsal vertebrae, the ribs, and the sternum. The considered visible structures in the image: 1) Thoracic aorta and ascending aorta 2) Left atrium 3) Pulmonary trunk Thoracic aorta and ascending aorta: Visible part of the structure: The roots of thoracic aorta and the ascending aorta at the level of the pulmonary trunk are well visualized. However the part, which is not visible, is the complete aortic arch. The surrounding anatomy: The parts around the thoracic aorta are the oesophagus and left intermediate bronchus. The oesophagus, with its accompanying plexus of nerves, lies on the right side of the aorta above; but at the lower part of the thorax it is placed in front of the aorta, and, close to the diaphragm, is situated on its left side. There are branches arising from the thoracic aorta (oesophageal branches) that contribute towards the major supply of blood to the oesophagus. The left bronchial arteries are general two in number and arise from the thoracic aorta. These provide supply to the left intermediate bronchus. The parts around the ascending aorta are the right auricle, which lies to the right of the root of ascending aorta. The right auricle is a small conical muscular pouch attached to the right atrium of the heart (as visible in the image). The pulmonary trunk lies to the top left of the ascending aorta. The part visible here is the surrounding the beginning part (it begins at the base of the right ventricle). It is associated with the ventricle just like the aorta is associated with the left atrium, i.e., the outlet vessel. The pathologies: Coarctation of the aorta involves narrowing of the aorta and it is a heart defect. In order to treat this the part of the aorta can be removed or valves may be replaced. A contraction of the aortic part visible in the axial plane might suggest pneumonia in a child. Left atrium: Visible part of the structure: The posterior view of the left atrium is clearly visible as located at the base of the heart and the level of the ascending aorta and the pulmonary trunk. The surrounding anatomy: The parts around the left atrium are the ascending aorta, superior vena cava and oesophagus. In a certain case of respiration infection, there might be anomalous drainage of the right superior vena cava to the left atrium. The relation of oesophagus to the aorta and that of the aorta and the left atrium ahs been mentioned before. Pathologies: Bronchogenic cyst in left atrium appears as a hypo-attenuated mass visible in the axial plane. The axial plane image therefore helps to spot this symptom for diagnosis of the cyst. Pulmonary trunk: Visible part of the structure: The visible part is the beginning of the trunk where it starts (the base of right ventricle). The entire arch of the trunk and its branches are off course not visible. The surrounding anatomy: The closest structure is the ascending aorta, which performs similar function as the pulmonary trunk. We can view the transverse plane of the aortic arch close at the trunk level. Pathologies: Studying the cell structures of the trunk one can identify the symptoms of pulmonary hypertension. The endothelial cells of the pulmonary trunk are polygonal and have tessellated borders and that of the aorta become small and elongated with tapering ends. The cross sectional image helps us understand and study this along with the positions of the different components of the heart. The systemic supply of the thorax is derived mainly from branches of the aorta, the chief systemic artery of the body. Coronal plane: The coronal plane divides the body into dorsal and ventral part. It is also called the frontal plane. This plane is perpendicular to the ground. This plane mainly allows the relation of the trachea and the main bronchi to the cardiovascular structures. The considered structures visible are: 1) The ascending aorta 2) Pulmonary trunk The left atrium is not visible but one can see the right atrium in this plane structure. Aorta: Visible part of the structure: The ascending aorta, the longitudinal portion of the aortic arch is visible. However, the beginning (outlet) and the complete arch are not visible. One cannot see the left atrium from where the aorta originates but the ascending part of the arch is visible clearly. The surrounding anatomy: Amongst the surrounding structures, the closest ones are the pulmonary trunk, the epicardial fat deposits, the superior vena cava and the right coronary artery. The structures of epicardial fat, right coronary artery and the pulmonary trunk have been discussed before. The superior vena cava is a large but short vein that carries de-oxygenated blood from the upper half of the body to the hearts right atrium. The right atrium is also visible here and lies just below the superior vena cava, which lies to the left of the aorta. Pathologies: In case of a four dimensional ultrasonography, blood flow through the ascending aorta and main pulmonary artery during systole is seen in the coronal planar structure through the atrioventricular valves (coronal plane). Congenital pathology of the aorta, including aortic arch anomalies and coarctation can be diagnosed on this plane. As per the treatment procedures for different such problems go, the ascending aorta and the aortic valve were replaced with a cryopreserved valved homograft conduit. Intrinsic aortic wall pathology in BAV (Bicuspid Aortic Valve) disease is related to aortic dilatation. In order to understand the effects of different metabolic activities on different parts of the heart, the coronal plane structures can be observed. A coronal three-dimensional gradient-echo sequence with asymmetric k-space acquisition can be used. The 136 x 512 matrix yielded voxel sizes of 1.33 x 0.64 x 1.0 mm. A timing-bolus acquisition is orientated in the coronal plane to include the aortic arch and can be obtained initially during free breathing. Pulmonary trunk: Visible part of the structure: The pulmonary trunk is clearly visible, rising from the right ventricle. The surrounding anatomy: Besides the ascending aorta (to the left of the trunk structure visible), the epicardial fat deposits lies to the bottom right of the pulmonary trunk while the right coronary artery lies immediately below the place where the trunk originates. The right coronary artery might abnormally originate from the pulmonary trunk in case of congenital anomaly. The right coronary artery originates usually from above the right cusp of the aortic valve and then travels down the right atrioventricular groove and reach the crux of the heart. A longitudinal part of the aorta is visible. This is a portion of the arch, but not the start or the beginning of it. The coronary artery is located at some distance from the aortic valve but when viewed and studied they are usually taken at different levels. Pathologies: One of the common anomalies have been mentioned above – when the right coronary artery abnormally originates from the pulmonary trunk. In this case the coronal plane would help the medical practitioners to study the structural abnormalities. A case of fatal pulmonary tumor revealed that the pulmonary trunk contained a firm, rubbery, white-gray, readily detachable mass, which distended and completely occluded the main pulmonary trunk and extended into the right and left pulmonary arteries and their branches. The coronal plane can give us a clear view of this problem and symptom. Sagittal plane: This is the plane, which divides the body into left and right halves and is also known as Lateral plane. It is any imaginary slice made from the top of the body down, running parallel to the midsagittal plane cutting the body into two halves of varying proportion. The considered structures visible are: 1) The ascending and descending aorta and the aortic arch 2) The pulmonary trunk 3) Left atrium Aorta: The visible structures: The ascending aorta, descending aorta and the aortic arch are all visible clealry. The aorta starting from the left ventricle and proceed to other parts of the body. The ascending aorta is the part lying between the heart and the aortic arch. The arch of aorta is the peak which appears like an inverted U-shape. The decending aorta is that part which starts from the point of the aortic arch (peak point) and comes down to divide the iliac arteries. Each part is clearly visible in this plane. Surrounding anatomy: The structures visible in the surroundings are left atrium, coronary sinus, ligamentum arteriosum, hemiazygos and the pulmonary trunk. The left atrium lies to the right of the descending aorta and to the bottom left of the ascending aorta. The entire part is clearly visible here. The coronary sinus lies to the right of the descending aorta and below the left atrium. The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the myocardium of the heart. The hemiazygos lies to the left of the descending aorta. The hemiazygos vein (vena azygos minor inferior) is a vein running superiorly in the lower thoracic region, just to the left side of the vertebral column. The pulmonary trunk lies below the aortic arch. The ligamentum arteriosum is a small ligament between the pulmonary artery and aortic trunk and lies below the aortic arch. Pathologies: Coarctation of the aorta can be diagnosed from studying his plane. Any part of the aorta can become contracted or narrow and the study of the plane shows which part to be treated. Blood flow through the ascending aorta and main pulmonary artery during systole is seen in a sagittal plane of the section through the interventricular septum and foramen ovale. Any problems related to the aorta can be comfortable studied from this plane. Pulmonary trunk: Visible structures: The pulmonary trunk is also clearly visible, arisng from the right ventricle. The longitudinal section thus shows the entire structure. Surrounding anatomy: The surrounding structures include the arch of the aorta, right ventricle and the ligamentum arteriosum. The aortic arch lies above the pulmonary trunk and so does the ligamentum arteriosum. Besides this the right ventricle lies at the beginning position of the trunk. The trunk acts as an outlet vessel for the right ventricle. The pulmonary trunk extends from the conus arteriosus of the right ventricle to the concavity of the arch of the aorta, to the left of the ascending aorta, where it divides into the right and left pulmonary arteries Pathologies: Any abnormality in the structure such as origin of coronary artery from the trunk, Aneurysm of the pulmonary trunk and other anomalies can be comfortably diagnoseda and analysed from this planar structure.this plane shows a clear view of the parts through which the trunk passes and hence gives a comprehensible view. Left atrium: Visible structures: The left atrium is clearly visible. The only view that is obscured is the cross sectional part which includes the cellular structure. The surrounding anatomy: The mitral valve, coronary sinus, ascending aorta, and the inferior pulmonary vein lie around the structure of the left atrium. The mitral valve lies to the bottom right of the left atrium, the coronary sinus to the bottom left, the pulmonary vein to the top left and the ascending aorta to the top right of the left atrium. All the structures are visible clearly as far as their longitudinal section is concerned. The mitral valve is a dual flap valve of the heart that lies between the left atrium and the left ventricle and controls flow. At the end of ventricular diastole, the valve shuts, and prevents backflow as the ventricle begins its systolic phase. Pathologies: Understanding the spatial relations between the oesophagus and the left atrium is important to reduce risks of oesophageal injury. This is ensured by this planar view, which gives a vivid picture of the interrelation between these structures. The uneven thickness of the posterior left atrial wall, the variable fibro fatty layer between the wall and the oesophagus are risk factors that needs to be considered during ablation procedure. Reference: Prives M., Lysenkov N., Bushkovich V.,1989. “Human Anatomy”, Mir Publishers, Moscow. Read More