Lateral abdomen X-ray positioning (erect)
An extra abdomen view, used when a routine one is not enough. The patient stands side-on, the beam passes from side to side, straight on to the receptor, and the centring point is the mid-coronal line at the iliac crest.
By the ScanFlo Editorial Team · Updated
In this section · X-ray positioning
- X-ray positioning guides
- Skull positioning
- Face & sinuses positioning
- Soft tissue neck positioning
- C-spine positioning
- Chest positioning
- Shoulder positioning
- Humerus positioning
- Elbow positioning
- Forearm positioning
- Wrist positioning
- Hand positioning
- T-spine positioning
- Abdomen positioning
- L-spine positioning
- Sacrum & SI joints positioning
- Pelvis positioning
- Hip positioning
- Femur positioning
- Knee positioning
- Tibia & fibula positioning
- Ankle positioning
- Foot positioning
Still being checked: a radiographer is reviewing this guide. If your department does it differently, follow your department.
Patient position
Lateral, erect. Stand the patient sideways to the bucky, arms folded above the head.
Centring & collimation
Central ray
lateralCentre: the mid-coronal line at the iliac crest.
Beam: lateral, perpendicular to the receptor.
Collimate: diaphragm to pelvis, anterior abdominal wall to spine
Distance, receptor & grid
| Setting | Value | Notes |
|---|---|---|
| SID | 110 cm | |
| Receptor | 35 × 43 cm | portrait |
| Placement | Erect (wall) bucky | Grid in |
| Angulation | None | Perpendicular to the receptor |
Marker & breathing
- Marker: R or L marker on the side nearest the detector
- Breathing: Suspend respiration.
Exposure by patient size
Treat these as a starting point. Your detector, your generator and the patient in front of you will all move the numbers.
| Patient size | kV | mAs (chart) | mAs (DR default) |
|---|---|---|---|
| XS | 90 | 20 | 8 |
| S | 90 | 32 | 12.5 |
| M | 90 | 40 | 16 |
| L | 90 | 63 | 25 |
These start from a classic film-screen chart (90 kV, 63 mAs at 140 cm) and are adjusted for a digital detector at 110 cm. The DR column is what ScanFlo's console suggests; each step up or down changes the mAs by about a quarter.
Image quality checklist
- Anterior abdominal wall and spine included.
- No rotation.
- The anatomical side marker is visible, correct and clear of the anatomy.
- Collimation borders are visible on all sides, no wider than the area requested.
Faults & how to fix them
| Fault | Cause | Fix |
|---|---|---|
| Anterior wall cut off | Centred on the spine | Centre on the mid-coronal line. |
Common questions
- Where do you centre for an abdomen lateral erect X-ray?
- The centring point is the mid-coronal line at the iliac crest.
- What distance and beam angle does an abdomen lateral erect need?
- 110 cm from the tube to the receptor. The beam passes from side to side, straight on to the receptor.
- What size receptor, and do you need a grid?
- Use a 35 × 43 cm receptor, portrait, in the wall bucky. A grid is needed.
- What should the patient do with their breathing?
- Ask them to stop breathing for the moment of the exposure.
- What goes wrong most often on an abdomen lateral erect?
- Anterior wall cut off. Usual cause: centred on the spine. The fix: centre on the mid-coronal line.
Try it in ScanFlo: the ScanFlo XR X-ray Room, coming soon, lets you set up a abdomen lateral erect in a 3D room and score your positioning. See ScanFlo XR →
Written by the ScanFlo team from everyday radiographic practice.