Chest X-Ray Technique: Posteroanterior and Apicolordotic Views
Standard Posteroanterior (PA) Chest Radiograph Technique
The standard PA chest radiograph should include both frontal and lateral views with technique optimized to include both anterior and posterior costophrenic angles 1. PA views are strongly preferred over portable anteroposterior (AP) imaging whenever feasible 1, 2.
Key Technical Requirements:
- Patient positioning: Patient stands facing the image receptor with chest against the detector, arms positioned to rotate scapulae laterally away from lung fields
- X-ray tube positioning: Positioned 6 feet (180 cm) behind the patient, directed horizontally at the level of T7 (though some variation exists in practice regarding horizontal versus angled tube) 3
- Exposure timing: Full inspiration to maximize lung expansion and visualization
- Image quality: Must adequately visualize both anterior and posterior costophrenic angles 1
The lateral view complements the PA view, though studies show it does not improve detection of certain conditions like tuberculosis 4. However, PA and lateral radiographs together have significantly greater sensitivity (83.9%) compared to single AP views (67.3%) for detecting conditions like pleural effusions 5.
Apicolordotic (Lordotic) Projection Technique
The apicolordotic view is a specialized projection designed specifically to visualize the lung apices by projecting the clavicles above the lung fields.
Specific Technique:
- Patient positioning: Patient stands approximately 1 foot in front of the image receptor, leaning backward with shoulders and upper back against the detector
- Tube angulation: X-ray tube angled 15-20 degrees cephalad (upward), or alternatively the patient leans back to create the lordotic position
- Central ray: Directed to enter at the level of the manubrium
- Purpose: Projects clavicles superiorly to allow unobstructed visualization of lung apices
Clinical Indications:
The lordotic projection is particularly valuable for:
- Suspected apical pathology including superior sulcus (Pancoast) tumors 6
- Tuberculosis evaluation when apical disease is suspected 4
- Clarifying lesions that may be obscured by overlying clavicles or first ribs on standard PA views
Critical Technical Pitfalls and Artifacts
Exercise extreme caution when interpreting lordotic films, as they produce significant artifacts that can lead to diagnostic errors 7:
Common Lordotic Artifacts:
- Apparent diaphragm elevation (not true elevation)
- Poor visualization of lung bases (bases appear compressed)
- Loss of aortic knuckle definition
- Apparent superior mediastinal widening (not true widening)
These artifacts are greatly exaggerated when lordosis coexists with actual pathology, patient rotation, or inadequate inspiration 7. A lesion that appears concerning on a lordotic view should be correlated with standard PA and lateral views before making clinical decisions.
Quality Control Factors:
For optimal lordotic imaging:
- Ensure adequate patient inspiration
- Minimize patient rotation
- Use consistent technique between standard and lordotic views when comparing
- Always obtain standard PA/lateral views first—lordotic views are supplementary, not replacement imaging 6
Modern Imaging Considerations
While standard chest radiography remains the initial imaging modality for most thoracic conditions 1, 2, 4, cross-sectional imaging with CT is superior for evaluating apical lesions and provides better anatomic detail 6. For suspected Pancoast tumors specifically, both chest CT and MRI are indicated, as MRI better demonstrates involvement of the brachial plexus and chest wall structures 6.
The lordotic view has become less commonly used in modern practice as CT imaging has largely supplanted it for detailed apical evaluation, but it remains a useful technique when CT is unavailable or when rapid bedside assessment is needed.