MRI of the brain is an incredible sensitive technology for detecting minor abnormalities in the brain. Therefore, findings such as this will need to taken into context of any symptoms your friend might be having and properly interpreted by which ever doctor
, such as a neurologist
, initially referred him for the test .
"Chronic microvascular ischemic changes" is a common finding in MRI in older people, and it typically means that there have been small tiny strokes (usually asymptomatic) due to damage to small blood vessels. This blood vessel damage is typically provoked by chronic medical problems, like high blood pressure or diabetes.
"Demyelinating plaques" are most classically seen in a multiple sclerosis
, a common disease which leads to progressive neurological problems, although there are multiple other conditions that can do this as well, including various infections.
I would suggest, therefore, that your friend go back to see their neurologist, or which ever other doctor is managing their care. They will be able to sit down and carefully explain the results of this MRI study. It is difficult to interpret the MRI study without knowing exactly what symptoms your friend has, or what triggered getting the study in the first place, and their doctor will be the one best suited to put things into context.