Chest Anatomy PDF 2024

Upper Airway/Chest R efe ren ce: Rad io graphic Po si tionin g & R el ated A nato my 1 1 th e di tion Bo n tr ager 1 0 th e di ti on R AD 10 1 Learning Outcomes: ◦ 6.00 Describe the anatomy and positioning of the thorax. ◦ 6...

Upper Airway/Chest R efe ren ce: Rad io graphic Po si tionin g & R el ated A nato my 1 1 th e di tion Bo n tr ager 1 0 th e di ti on R AD 10 1 Learning Outcomes: ◦ 6.00 Describe the anatomy and positioning of the thorax. ◦ 6.01 Identify the following on an image of the thorax: 1. Chest 1. Mediastinum 2. Heart 3. Clavicle 4. Vertebral column 5. Lungs 6. Cardiophrenic Angle 7. Costophrenic Angles 8. Diaphragm 9. Aorta 10. Hilum 11. Bronchi 12. Carina Learning Outcomes: ◦ 6.02 State the number of ribs that are visualized above the diaphragm on a good P.A. chest. 6.03 Describe three reasons for performing erect chest radiographs. 6.04 State the reason why chest radiography should be performed at 72”. 6.05 Describe the routine and special projections for chest radiography. 6.06 Explain how blood flows normally through the normal human heart. 6.07 Explain the basic electrical conductivity of the heart. 6.08 Describe the routine projections for the ribs, sternum and AC joints. 6.09 Discuss why each of the above projections may be requested. 6.10 Identify the structures that are located within the mediastinum. 6.11 Identify the structures that are located within the hilum. 6.12 State the number of lobes for each lung and their associated fissures. 6.13 Identify the parenchyma and pleura. 6.14 State the four parts of the respiratory system. 6.15 State the beginning and end points for the trachea.  Bony Thorax Divisions of Chest Respiratory System Anatomy Mediastinum  Bony Thorax ◦ Part of the skeletal system ◦ Provides protective framework for parts of the chest involved with breathing and blood circulation ◦ Thoracic viscera: consists of lungs, and remaining thoracic organs contained in the mediastinum ◦ Parts of the Bony Thorax ◦ Sternum ◦ Clavicles -2 ◦ Scapulae -2 ◦ Ribs -12 pairs ◦ Thoracic Vertebrae -12 Fig 2.1 Copyright 2025 by Elsevier Landmarks Vertebra (C7 spinous process) prominens Level of T1 body Jugular notch *Manubrial or Level of T2/T3 Suprasternal notch Sternal Angle Level of T4/T5 Xiphoid process (Ensiform) Level of T9/T10 Fig 2.2 Copyright 2025 by Elsevier  PARTS OF THE RESPIRATORY SYSTEM Purpose: Exchange of gaseous substances between air and blood Four Parts: Pharynx, Trachea, Bronchi, & Lungs Diaphragm: primary muscle of inspiration -Each half = hemidiaphragm Fig 2.3 Copyright 2025 by Elsevier  Upper Airway ◦ Hard Palate & Soft Palate – roof of oral cavity ◦ Soft: uvula –lower posterior portion ◦ Boundary between nasopharynx & Oropharynx ◦ Pharynx – passageway for food, fluid,& air ◦ 3 divisions 1. Nasopharynx ◦ Houses opening of eustachian or auditory tube & pharyngeal tonsils 2. Oropharynx ◦ Contains the palatine and lingual tonsils 3. Laryngopharynx ◦ Extends from epiglottis & connects to esophagus Fig 2.4 Copyright 2025 by Elsevier ◦ Esophagus – posterior to larynx & trachea  Larynx (Voice Box) ◦ Larynx ◦ Cage-like, cartilaginous structure (1-1.5in) ◦ Organ of voice ◦ Suspended by Hyoid Bone ◦ Level of C3-C6 ◦ Vocal Cords ◦ Sounds are made as air passes between cords ◦ Located within larynx Fig 2.5 Copyright 2025 by Elsevier ◦ Thyroid Cartilage ◦ Anterior wall of larynx ◦ LEVEL of C5 ◦ Anterior projection – palpated easily – Laryngeal Prominence (Adam's apple) ◦ Cricoid Cartilage ◦ Ring of cartilage that forms the inferior and posterior wall of larynx ◦ Attaches to trachea ◦ Epiglottis ◦ Resembles a leaf ◦ Attaches to thyroid cartilage ◦ Flips down and covers trachea during the act of swallowing Fig 2.6 Copyright 2025 by Elsevier  Trachea (windpipe) ◦ Connects larynx to bronchi tree ◦ Fibrous muscular tube ◦ 16-20 C-shaped rings of cartilage are embedded in anterior wall ◦ Keeps airway open by preventing the trachea from collapsing during expiration ◦ Extends from (C6) to level of (T4/T5) ◦ trachea divides: Carina @ T4/T5 Fig 2.8 Copyright 2025 by Elsevier  Endocrine Glands – Imaged with Respiratory System ◦ Thyroid Gland ◦ Located anteriorly just below thyroid cartilage ◦ More radiosensitive than most body structures or organs ◦ Stores and releases hormones to aid in metabolism – help regulate growth and development in children ◦ Lowers calcium levels in the blood ◦ Parathyroid Glands ◦ Small round glands embedded in posterior surface of thyroid (2 on each side – 4 total) ◦ Stores and secretes hormones that aid in specific blood function – increases calcium levels in the blood ◦ Thymus Gland– disappears in adulthood ◦ Inferior to thyroid gland & Anterior and superior to the heart ◦ Large role in development of immune system Fig 2.8 Copyright 2025 by Elsevier ◦ Thymic lymphocytes (T cells) – rejects things foreign to the body Fig 2.9 Copyright 2025 by Elsevier Fig 2.10 Copyright 2025 by Elsevier  Bronchial Tree – Primary Bronchi (Bronchus) ◦ Right and Left Primary Bronchi ◦ AKA right and left main stem bronchi ◦ Split by carina ◦ Right Primary Bronchus ◦ Wider, Shorter, and More Vertical than left ◦ Food particles or other foreign objects more likely to enter and lodge in right bronchus Fig 2.12 Copyright 2025 by Elsevier  Bronchial Tree – Secondary Bronchi ◦ Right Bronchus divides into 3 secondary bronchi ◦ Left Bronchus divides into 2 secondary bronchi WHY? - ◦ Secondary Bronchi divide into smaller branches called bronchioles (Terminal Bronchioles) ◦ Terminal Bronchioles terminate into small air sacs called alveoli Fig 2.13 Copyright 2025 by Elsevier ◦ 2 lungs contain approx. 500-700million alveoli ◦ Oxygen and carbon dioxide are exchanged in the blood through the thin walls of the alveoli  Term for Lungs collapsed lung? ◦ Composed of Parenchyma (light, spongy, highly elastic substance) ◦ Allows for expansion and contraction of lungs ◦ Each lung is contained in a double-walled sac called the pleura ◦ Outer layer: parietal pleura ◦ Inner layer: Pulmonary or visceral pleura ◦ Space between the double-walled pleura – Pleural cavity ◦ Contains lubricating fluid that allows movement during breathing ◦ Can be visualized radiographically when lung collapses or air/fluid collects between two layers ◦ Pneumothorax ◦ Hemothorax Fig 2.15 Copyright 2025 by Elsevier ◦ Pleural Effusion  Lungs Continued… ◦ Right Lung: ◦ 3 lobes ◦ 2 fissures ◦ Left Lung: ◦ 2 lobes ◦ 1 fissure Fig 2.15 Copyright 2025 by Elsevier  Lungs Continued… ◦ Apex ◦ Rounded upper area above the level of the clavicles ◦ Base ◦ Lower concave are of each lung ◦ rest on the diaphragm (muscular partition that separates the thoracic and abdominal cavities) ◦ Costophrenic Angles ◦ Outermost lower corner of each lung ◦ Cardiophrenic Angles Fig 2.19 Copyright 2025 by Elsevier ◦ Angles closest to the heart Fig 2.21 Copyright 2021 by Elsevier HILUM AKA the root region Central area of each lung Bronchi, blood vessels, lymph vessels, and nerves enter/leave the lungs Fig 2.18 Copyright 2025 by Elsevier  Mediastinum ◦ The medial portion of the thoracic cavity between the lungs ◦ Four Important Radiographic structures: 1. Thymus gland 2. Heart & great vessels 3. Trachea 4. Esophagus Fig 2.22 Copyright 2025 by Elsevier  Additional mediastinum anatomy ◦ Coronary vessels ◦ Azygos vein ◦ Hemiazygos vein ◦ Thoracic duct ◦ Lymph nodes https://www.earthslab.com/wp-content/uploads/2017/07/Posterior-Mediastinum-Contents.jpg  Time Out! ◦ Practice labeling/identifying anatomy on the Chest x-ray! ◦ Apex of the lungs? ◦ Costophrenic angles? ◦ Cardiophrenic angles? ◦ Base of the lungs? ◦ Trachea? ◦ Carina? ◦ Primary bronchus? ◦ Ribs? ◦ Clavicle? ◦ Scapula? ◦ Heart? ◦ Thoracic Spine? ◦ Diaphragm? ◦ Mediastinum? ◦ Hilum? https://prod-images-static.radiopaedia.org/images/157210/332aa0c67cb2e035e372c7cb3ceca2_gallery.jpg HEART ◦ Heart and the roots of the great vessels are enclosed in a double-walled sac called the pericardial sac ◦ Heart is located ◦ Posterior to body of sternum ◦ Anterior to T5 to T8 ◦ Lies oblique in the mediastinum ◦ 2/3 of the heart lies left of median plane ◦ Great Vessels (in the mediastinum) ◦ Inferior & superior vena cava ◦ Aorta ◦ Large pulmonary arteries and veins Great Vessels ◦ Inferior Vena Cava ◦ Large vein that returns blood to the heart from the lower half of the body ◦ Superior Vena Cava ◦ Large vein that returns blood to the heart from the upper half of the body ◦ Aorta (3 parts) – largest artery in the body ◦ Ascending aorta – coming up out of the heart ◦ Arch of the aorta – (3 arterial branches) ◦ Brachiocephalic ◦ Left common carotid ◦ Left subclavian ◦ Descending aorta – passes through diaphragm into abdomen (abdominal aorta) ◦ Large pulmonary arteries and veins ◦ Return and supply blood to and from the lungs  Coronary Vessels ◦ Coronary Arteries ◦ Located around and inside the heart muscle ◦ RCA (Right Coronary Artery) ◦ Supplies blood to right atrium and right ventricle ◦ Branches supply the SA and AV nodes ◦ LMCA (Left Main Coronary Artery) ◦ Supplies blood to left atrium and left ventricle ◦ Branches supply 2/3 of the interventricular septum https://www.tekportal.net/wp-content/uploads/2018/11/ventricular-artery-1.jpg  Azygos & Hemiazygos Veins ◦ Azygos Vein ◦ Enters thorax through aortic hiatus ◦ Enters superior vena cava at T4 ◦ Hemiazygos Vein ◦ Arises from the left ascending lumbar vein ◦ Joins the azygos vein at T9 ◦ Posterior Intercostal veins join – this azygos system ◦ Azygos system is responsible for draining the thoracic wall https://media-us.amboss.com/media/thumbs/big_5ad610708b3fd.jpg and upper lumbar region  Blood Flow Vena Cava Right Tricuspid Right atrium valve ventricle Pulmonary Pulmonary Pulmonary valve arteries Lungs veins Left atrium Bicuspid or Left Aortic Mitral valve ventricle valve Aorta  3 Branches Off The Aortic Arch ◦ Brachiocephalic Artery ◦ Left Common Carotid Artery ◦ Left Subclavian Artery https://img.stevegallik.org/what_is_cardiovascular_aorta_circles.jpg  Electrical Conductivity of the Heart ◦ Starts at SA node ◦ AV node ◦ Bundle of His ◦ Left and Right bundle branches ◦ Divide into the Purkinje fibers  Thoracic Duct ◦ Main lymphatic channel for the return of chyle to the venous system ◦ Chyle: made of lymph and fat droplets ◦ Lymph: fluid that carries fat and proteins to help fight germs & keep body fluid levels normal ◦ Enters thoracic cavity through aortic hiatus ◦ Located between the aorta and azygos vein, posterior to esophagus https://healthjade.net/wp- content/uploads/2019/05/Thoracic-duct-anatomy.jpg  Mediastinum Lymph Nodes ◦ Can become enlarged dure to infections, cancer, and inflammatory diseases ◦ Clinical Application: Enlarged lymph nodes can sometimes show up on chest x-rays and other imaging https://radiologyassistant.nl/assets/mediastinum-lymph-node- map/a5097977aaaadb_mediast-3-met-vcs.jpg  CHEST X-RAY https://pbs.twimg.com/media/EHFz-o2XUAEbZaa.jpg REVIEW/PRACTICE Quiz Me: ◦ Define Pleural Effusion: ◦ Define Hemothorax: ◦ Define Pneumothorax: ◦ Practice labeling anatomy on a chest x-ray (slide 19) ◦ Steps on how air gets from your nose through your lungs Quiz Me: ◦ Which lung are you more likely to aspirate into? Why? ◦ Where is the esophagus & trachea located in relation to one another? ◦ What keeps the trachea from collapsing? ◦ Where does the trachea begin and end? Quiz Me: ◦ What level is the vertebra prominens? ◦ What is the vertebra prominens? ◦ What level is the jugular notch? ◦ What level is the sternal angle? ◦ What level is the xiphoid process? Quiz Me: ◦ 3 parts of the pharynx? ◦ What is the larynx? ◦ What suspends the larynx? ◦ What does the epiglottis do? ◦ Other name for Adam’s apple? Quiz Me: ◦ What does the thyroid gland do? ◦ What does the Thymus gland do? ◦ What does the parathyroid glands do? Quiz Me: ◦ What substance is the lungs made of? ◦ Name of double-walled sac that surrounds the lungs? ◦ Inner layer: ◦ Outer layer: ◦ Space between layers: ◦ How many lobes do you have in each lung? ◦ What separates each lobe? Quiz Me: ◦ What is found in the Hilum? ◦ What is the 5 main structures located in the mediastinum? ◦ Sac that surrounds the heart? ◦ 3 branches off the aorta? Quiz Me: ◦ Steps of blood flow through the heart? ◦ Electrical conductivity of the heart?