Gunshot chest: spectral insights

30 yo M shot in the left chest, stable on arrival to the ED.

Conventional CT shows bullet entering left chest, going through anterior aspect of the left lung, somehow missing the central arteries, going through anterior right lung, and likely exiting the right axilla. Large lung opacity along bullet tract, consistent with lung injury. 

Unfortunately, this much is fairly routine stuff. 

On spectral analysis, lung injury shows a central non-perfused component. This corresponds to the lung laceration from the bullet tract. There is a clear hyper-perfused peripheral component to the lung injury, beautifully illustrated on the sagittal images.

Is the hyper-perfused periphery

-the blast injury (akin to the lung contusion in trauma),

-lung response to the injury, or

-just compressed lung?

Here is hoping that spectral CT will help us in asking more questions, the one sure way to making new discoveries!

More importantly, I am hoping and praying to see more lucky survivors like this, there are way too many who do not do well.

Volume rendered image from CT shows bullet injury site (yellow arrow). Note right chest tube.

Bullet tract form left to the right in the anterior chest, somehow missing central vascular structures. Note punctate bullet fragments.

Oblique axial shows the injury tract

Iodine overlay (same section as above) shows increased perfusion in the periphery of the tract

Sagittal iodine overlay image beautifully shows increased perfusion at the periphery of the tract. Note the hemothorax posteriorly, and small anterior pneumothorax.