Osmotic pressure calculation
π = iMRT
where i = Van 't Hoff factor
M = fact molarity
R = gas constant = .08206 l-atm/mole-ºK
T = absolute temperature degree K
T = 310 ºK
M = 100 facts / 1.5 liters brain volume = .0095 facts/liter
i = 1 (conservative, facts do not aggregate)
π = .242 atm = 3.55 psi.
Since atmospheric pressure is 14.7 psi, the above calculation strongly suggests the head would promptly implode.