Seeing It First: How Recognizing Sinking Flap Syndrome Can Change Patient Outcomes

Sinking flap syndrome is a potentially serious complication that develops after decompressive craniectomy.

The underlying concept is relatively straightforward.

Following removal of a large portion of the skull, atmospheric pressure can begin to exceed intracranial pressure at the craniectomy site, and this pressure imbalance results in inward collapse of the scalp flap and underlying brain.

The consequences can be substantial.

If you're following along with me in figure one, the image nicely illustrates the effect a sinking flap can have on the underlying brain and midline structures.

You can appreciate how the inward collapse of the scalp flap results in distortion of normal intracranial anato-anatomy, setting the stage for progressive mass effect and herniation.

These patients may develop midline shift, ventricular compression, subfalcine or transtentorial herniation, reduced cerebral perfusion, altered cerebrospinal fluid dynamics, and progressive neurological decline.

The good news is that the treatment is usually very effective.

Cranioplasty rapidly restores the normal intracranial pressure dynamics and can produce dramatic neurological improvement.

And you can see an example in figure two, shown on the screen.

It shows axial CT images obtained at the time of the sinking flap syndrome diagnosis and immediately after cranioplasty, the image on the right.

So restoration of the cranial wall leads to normalization of intracranial anatomy and reversal of the mass effect that developed as a consequence of the sinking flap.