Chest Lateral is a radiography positioning projection of the Thorax. Left or right lateral upright chest projection. SID 72". The centering point is located level of t7, midway between the sternum and the vertebral column.. The central ray is horizontal, perpendicular to ir. centered to t7.. Image-quality criteria include both lungs visualized in entirety with sharp costophrenic angles., scapulae rotated clear of the lung fields.. Standard exposure ranges from 110 to 125 kVp, 2 to 5 mAs, at an SID of 72 inches (180 cm).
Anatomy demonstrated
- Both lungs from apex to costophrenic angle.
- Mediastinal silhouette including heart and great vessels.
- Thoracic vertebral bodies.
- Diaphragm.
- Ribs and intercostal spaces.
- Sternum in profile.
Patient preparation
- Verify patient identity using two identifiers.
- Remove all radiopaque objects from the chest area.
- Explain breathing instructions: inspiration on the second breath in, hold.
- Position patient erect, lateral surface of chest against receptor.
- Raise both arms above the head to clear the shoulders and soft tissues.
Position & centering point
Level of T7, midway between the sternum and the vertebral column.
Central ray
Horizontal, perpendicular to IR. Centered to T7.
Exposure / technique
- kVp
- 110–125
- mAs
- 2–5
- SID
- 72" (180 cm)
- Notes
- High-kVp technique. Grid required. Shows mediastinal silhouette and vertebral column.
Image-quality criteria
- Both lungs visualized in entirety with sharp costophrenic angles.
- Scapulae rotated clear of the lung fields.
- Mediastinal silhouette clearly visible without superimposition.
- Vertebral bodies visible through the heart shadow.
- No rotation evident from bilateral costophrenic angle symmetry.
- Diaphragm sharp and clearly visible.
Common errors / ARRT traps
- 1 Rotation forward or backward causes asymmetry of the lung fields.
- 2 Arms not raised high enough keeps shoulders in the field.
- 3 Chin dropped too far forward or back causes rotation.
- 4 Inadequate inspiration flattens the diaphragm and reduces rib visibility.
- 5 Off-centered CR clips the lung apices or costophrenic angles.
Clinical indications
- Evaluation of mediastinal masses or silhouette changes.
- Assessment of pleural effusions or infiltrates seen on frontal views.
- Evaluation of cardiac size and configuration.
- Vertebral body evaluation and assessment of kyphosis.
Aligned to the 2025 ARRT Content Specifications.