Sign in or 
| Version | User | Scope of changes |
|---|---|---|
| Mar 31 2008, 9:07 AM EDT | M.J.Fuller | 3 words added, 2 words deleted |
| Mar 19 2008, 1:33 AM EDT | M.J.Fuller | 8 words added |
Changes
Key: Additions Deletions
Introduction
| There has been a longstanding practisepractice in radiography to perform lateral thoracic spine radiography using a long exposure time to blur out lung and other soft tissue markings. It is unclear why this technique was not seen as equally applicable to the AP projection. Equally, there are patients who present for lumbar spine radiography who have so much small bowel gas that the bony anatomy is almost completely obscured using a short exposure time technique. Why not use breathing technique on these patients? |
Breathing Technique Case Study
| This is basically an exposure technique for lumbar spine radiography. This patient has presented to the Emergency Department with back pain following a fall. The patient has a history of disseminated cancer and was considered to be at risk of a pathological fracture. The patient was referred for lumbar spine radiography with special emphasis on the L3- L5 vertebra. |
Images
The lateral spine radiograph was performed using the automatic exposure chamber at 85 kVp. An acceptable exposure was achieved but the area of interest is partially obscured by bowel gas. The mAS was determined by the AEC device and was recorded as 50 mAS.
The radiographer considered that the area of interest (L3 - L5) was sufficiently obscured by bowel gas to warrant a repeat view.
The repeat radiograph was performed using a manual exposure technique as follows
85kVp 50mA 1.0 sec
This is the same mAS as used previously but with a set exposure time of 1.0 seconds. The area of interest is now demonstrated without the detracting overlying bowel gas. This repeat image is more likely to demonstrate a pathological fracture in the area of interest that the original lateral.
There is no clearly demonstrated crush fracture or other acute pathology. There is minor osteophytic lipping and some minor wedging of the T12 vertebral body.
It is noteworthy that the spinous processes have been inadvertently coned off.
Summary
A breathing exposure technique can be used for all torso spine radiography. It comes with an increased risk of movement unsharpness and should be used judiciously after assessing the patient's likelihood of holding still during the exposure. The longer the exposure time, the greater theblurringthe blurring of the soft tissue structures and the greater the likelihood of movement unsharpness.
....back to the applied radiography home page here
