heat transfer model of hyporthermic intracarotid infusion of cold saline for stroke therapy a 3dimensional hemispheric computational brain model is developed to simulate infusion of cold saline in the carotid arteries in terms of brain cooling for stroke therapy the model is based on the pennes bioheat equation with four tissue layers white matter gray matter skull and scalp the stroke lesion is simulated by reducing blood flow to a selected volume of the brain by a factor of onethird and brain metabolism by 50 a stroke penumbra was also generated surrounding the core lesion blood volume reduction 25 metabolism reduction 20 the finite difference method was employed to solve the system of partial differential equations this model demonstrated a reduction in brain temperature at the stroke lesion to 32 degrees c in less than 10 minutes