Modeling Brain Cooling Helmets for Ischemia Patients
Wiechecki, Julie; Ranganath, Neel; McDonough, Brendan; Wind, Jessica
In this project, we modeled the effectiveness of a cooling cap designed to lower brain temperatures by approximately 3°C in order to cause temporary hypothermia in the brain and thereby prevent further injury caused by cerebral ischemia. Cerebral ischemia is a condition in which blood flows preferentially through certain blood vessels in the brain and not through others, resulting in certain sections of the brain receiving insufficient blood flow for nutrient uptake and waste removal, potentially resulting in a stroke. Using the modeling program COMSOL Multiphysics, we simulated the brain temperature that results from the use of a cooling helmet consisting of a cap containing flowing coolant. The model incorporates convective flow of the coolant in the cap, and heat conduction through various modeled layers of the head. Our model showed that cooling occurred by the predicted conduction and convection mechanism and our results matched closely with those obtained from the literature, therefore validating our model. Initial results showed appropriate brain cooling; however, damage to the scalp occurred. Time of application and temperature of coolant were then successfully optimized to eliminate scalp damage while maintaining effective brain cooling. Even cooling the brain just a few degrees, as achieved in our model, reduces the extent of brain damage following cerebral ischemia. The use of this model provides insight into the optimal treatment conditions for using the cooling cap in a clinical setting.