Week 4: Session 7 – Chest, Abdomen, and Extremity Radiography

Text Explanation for Session 7

1. Chest Radiography

• Standard Projections:
  The two most common views used in chest radiography are Posteroanterior (PA) and Lateral views.

  • PA View: This is the most common chest X-ray projection. The patient stands with their chest against the image receptor and shoulders rolled forward to move the scapulae out of the lung fields. The X-ray beam is directed from behind the patient (posterior) to the front (anterior), which helps reduce the magnification of the heart and provides a more accurate image of the thoracic anatomy.

  • Lateral View: The lateral view is taken with the patient's side against the image receptor. This projection helps provide depth and spatial relationship information about structures in the chest, such as the heart, lungs, and diaphragm.

• Key Anatomical Landmarks for Chest Radiography:

  • Clavicles: Proper positioning ensures that the clavicles appear equidistant from the spine, indicating that the patient is not rotated.

  • Diaphragm: The diaphragm should be visible, with the right side typically appearing slightly higher than the left due to the liver.

  • Heart: In a well-positioned PA chest X-ray, the heart size should appear within normal limits (less than half the width of the chest).

• Breathing Instructions:
  Instruct the patient to take a deep breath and hold it during the exposure. This expands the lungs and allows for better visualization of the lung fields.

2. Abdominal Radiography

• Standard Projections:

  • Anteroposterior (AP) Supine: This view is most commonly used for abdominal radiography. The patient lies on their back, and the X-ray beam passes from front to back (anteroposterior). This projection allows for visualization of abdominal organs, including the liver, spleen, intestines, and kidneys.

  • Erect (Upright) View: In some cases, an erect view of the abdomen is obtained, especially when looking for air-fluid levels, which can indicate bowel obstruction or perforation.

• Key Anatomical Landmarks for Abdominal Radiography:

  • Diaphragm: The diaphragm should be included in the image to assess any air under the diaphragm, which may indicate free air in the abdominal cavity (a sign of perforation).

  • Pelvic Bones: The iliac crests are often used as a landmark to ensure proper positioning.

  • Psoas Muscles: These muscles, which run along the sides of the lumbar spine, should be visible, as their absence may indicate pathology.

• Patient Preparation:
  Patients should remove any metal objects (e.g., jewelry, belts) that could obscure the image. In some cases, patients may be asked to fast before the exam.

3. Extremity Radiography

• Upper Extremity Projections:

  • Anteroposterior (AP) View: For imaging bones like the humerus, radius, and ulna, the AP view is commonly used. The patient is positioned so the X-ray beam passes from front to back.

  • Lateral View: The lateral projection helps provide depth information and is useful for assessing fractures and joint alignment.

  • Oblique View: An oblique view can be taken at a 45-degree angle to better visualize joints or fractures that may not be seen in the AP or lateral views.

• Lower Extremity Projections:

  • AP View: Commonly used for the femur, tibia, fibula, and foot.

  • Lateral View: Helps assess fractures and joint spaces in the lower extremities.

  • Oblique View: Used to visualize fractures and abnormalities in areas like the ankle or knee.

• Key Anatomical Landmarks for Extremity Radiography:

  • Humerus and Shoulder: The shoulder joint should be properly centered in the image.

  • Knee Joint: For knee imaging, ensure the patella is properly centered.

  • Ankle Joint: Ensure the lateral malleolus and medial malleolus are visible in the image.