Presentation
Contact sport injury, hit the left upper quadrant. Sharp pain in the respective region.
Patient Data
- Minimally displaced fracture of the 6th rib on the left (see key image below).
- No clear evidence of pneumothorax, though there is a subtly increased lucency over the left hemidiaphragm.
- Small amount of hypoechogenic free fluid first seen in the Morrison's pouch is a red flag and a hard evidence of trauma. The decision of to perform a CT STAT is made at this point, the exam is shortened to a focused evaluation of large organs.
- More free fluid noted around the spleen, close to the lower pole of it a thin echogenic line is visible in the splenic parenchyma (see annotated image), indicating laceration. Most of the spleen seems to be vascularized. The exam was discontinued and the patient was transferred to the CT suite.
Note: This was a STAT bedside US performed in the ER. Annotation and image documentation are both nonstandard.
- CT confirms a laceration of the spleen (AAST grade III). Note that the amount of free fluid increased significantly even though only minutes passed between the CT and US exams.
- A small left basal pneumothorax is clearly seen with discrete contusion dorsally (see representative lung window image).
1. zoomed in key image highlighting the fracture of the 6th rib, and the ill-defined basal lucency which raises the possibility of pneumothorax.
2. Thin hyperechogenic line within the lower pole of the spleen - the ultrasonic imaging correlate of the CT-confirmed splenic laceration.
Case Discussion
Supine CXR is relatively insensitive to small pneumothoraces with most signs being indirect such as an ill-defined excess lucency over the hemidiaphragm as in this case, or the well-known but infrequently encountered deep sulcus sign.
Ultrasound is very sensitive to abdominal free fluid but may underestimate solid organ damage.