Normal Chest X-Ray PDF Lecture 2, FALL 2024-2025

Normal Chest X-Ray By: Dr./ Nesreen Mohey Lecture 2 FALL 2024-2025  Intended Learning Outcomes By the end of this session, you should be able to: - Identify the routine chest X-ray views. 2 - Enumerate the system...

Normal Chest X-Ray By: Dr./ Nesreen Mohey Lecture 2 FALL 2024-2025  Intended Learning Outcomes By the end of this session, you should be able to: - Identify the routine chest X-ray views. 2 - Enumerate the systematic approach to a normal X-ray film. - Assess the technical quality of chest X-ray Film.  Chest X-Ray Views The most common chest X-ray views: 1- Postero-anterior (PA) view: The standard projection, performed standing with full inspiration. 2- Lateral view: Usually performed erect left lateral. 3- Antero-posterior (AP) view: Portable chest X-ray, inferior in quality to PA view.  Systematic Approach to a Normal Chest X-ray A- Airways B- Bones C- Cardiac sihouette D- Diaphragm E- Effusion (i.e pleura) F- Fields (i.e Lung fields) G- Gastric bubbles H- Hilum  Airways Trachea. Right main bronchus Left main bronchus - The right main bronchus is straighter and wider than the left, making aspirated foreign bodies (if small enough) are more likely to end up in the right bronchus than the left.  Bones There are four bony structures: 1- Ribs 2- Clavicle 3. Sternum 4. Vertebral bodies  Cardiac Silhouette & Mediastinum Structures which compose the silhouette:  Diaphragm and Pleura Diaphragm: Normally, the right hemidiaphragm is slightly higher than the left presumably to the liver directly beneath it. Pleura: - The pleural is a double membrane that surrounds each lung. - Rt. and Lt. costophrenic angles are two spaces on either sides where the diaphragm meets the thoracic wall  Lungs 3 Fissures: - Horizontal fissure: at the right lung only. - Oblique fissures: at the right and left lungs. - Fissures are dividing the right lung into two lobes and the left lung into two lobes. Right lung lobes Left lung lobes  Lung Zones - Apical Zone: Is the level of the clavicle or above. - Upper Zone: From the clavicle down to the superior aspect of the hilum. - Mid Zone: Includes anything at the level of the hilum. - Lower Zone: Is anything below the hilum.  Lateral X-ray View - Retrosternal space - Retrocardiac space 13 - Spine sign.  Gastric Air Bubbles A small pocket of air seen under the left hemidiaphragm, usually represents air in the stomach. (Differentiate it with pneumoperitonieum). Lung Hilum Lung hilum at the medial aspect of each lung, each hilum contains the following: - A main bronchus. - Pulmonary artery. - Pulmonary veins. - Bronchial arteries &veins. - Lymph nodes. - Nerves.  Assessment of Technical Quality of Chest X-Ray Film Factors affecting technical quality Rotation: - One or both costophrenic angles may not be visible. - Size and shape of cardiac silhouette may be distorted. In PA chest film, to rule out rotation, a line drawn that connects the spinous process of the vertebrae should bisects the distance between the medial ends of two clavicles. -When the patient is rotated, the spinous processes will be closer to the clavicle on the side that is rotated forwards.  Posterior Ribs Inadequate inspiration - Chest X-ray is taken during full inspiration. - At PA view, the 9th-10th posterior ribs should be visible. - While the 6th -7th anterior ribs should be visible. Anterior Ribs  Consequences of inadequate inspiration: Consequences of Inadequate Inspiration - Lung volumes appear falsely low. - Lung markings appear falsely prominent……leads to false appearance of pulmonary edema. - Cardiac silhouette and mediastinum may appear falsely enlarged. Suboptimal penetration. * Physical factors which determine “low exposure” vs. “ high exposure”: - Duration of exposure. - Energy of photons. - Source to image distance (SID): For PA film, the standard distance is 6 feet, but for portable film, this may need to be adjusted depending upon the situation. * Radiology technologist uses 3 parameters to vary these factors: mAs, kVp, SID. These determine both contrast and over film brightness.  Assessing Exposure/Penetration -Exposure/Penetration of a PA/AP chest X ray is considered good when the outlines of the vertebral bodies are visible (By focusing on the intervertebral spaces. THANK YOU 21 Dr. Nesreen Mohey [email protected] www.gu.edu.eg