I showed in 2011 (Mills et al J Neurosurgery 20i;1 114:77-84) that if you give an oral dose of EPA and DHA right after an induced brain injury and continue supplementation for 30 days, you reduce the brain damage by 98%. That seems a lot easier that trying to inject an emulsion that has a limited lifetime in the refrigerator.
An American study has demonstrated the beneficial effect of injections of omega-3 fatty acids on the brains of mice affected by stroke at birth. The discovery could pave the way for new treatments for infant and adult stroke victims. Researchers at the Columbia University Medical Center (CUMC) evaluated the neurological health of mice at 24 hours, and at eight and nine weeks, after brain injury was sustained.