Brain Swelling Simulator Guides TBI Emergency Care

A new tool can minimize potential complications of decompressive craniectomy by helping surgeons select the optimal opening needed to help relieve swelling after traumatic brain injury (TBI).

Researchers at the University of Oxford (United Kingdom) and Stanford University (CA, USA) conducted a study to examine the potential stresses generated by brain swelling and the evolution of the bulging shape associated with the process. To do so, they reviewed medical scans showing the amount of swelling for different types of TBI lesions. They then created mathematical estimates to help predict how an injury would affect different parts of the brain.

Once they were done designing the system, then ran different scenarios through the simulation to explore stress areas created during the decompressive craniectomy procedure. They found that while the elastic energy of brain matter decreases throughout the process, large stresses develop close to the craniectomy opening. At the point of contact, the stresses exhibit a singularity similar to the ones found in the classic punch indentation problem, with zones of either high shear stresses or high neuronal axon stretching.

They then studied the stresses generated by brain swelling and the evolution of the bulging shape associated with the process, and concluded that serious damage occurred if axons expanded near or above 30%. The resulting simulation graphically displays stress singularities in different parts of the brain. Severe trauma is shown in red, areas that sustained mild damage in green, and safe areas are blue, thus giving surgeons a visual guide to decide on the best place to perform the decompressive craniectomy. The study was published on September 21, 2016, in Physical Review Letters.

“When a swelling soft solid is rigidly constrained on all sides except for a circular opening, it will bulge out to expand as observed during decompressive craniectomy, a surgical procedure used to reduce stresses in swollen brains,” concluded senior author Ellen Kuhl, PhD, of the living matter laboratory at Stanford University, and colleagues. “This tool can minimize potential complications by telling surgeons the optimal place to cut and how large the hole should be, depending on the type of injury.”

Related Links:
University of Oxford
Stanford University