>At the tip of the right temporal lobe is a one-quarter by one-quarter inch similar appearing purple contusion. Only very minimal contusion is present at the tip of the left temporal lobe. This area of contusion measures only one-half inch in maximum dimension.<

I think it means that the perp was pushing her head against something hard -like the headboard or the floor- with one hand , using a thumb on the right temporal lobe and another finger on the left. The other hand would then be free to do other things. The hand that was free to do other things would (probably)have been the perps dominant hand. A purple contusion would be a bruise? Do bodies bruise after death?
Is it right/left as you are looking at the person or the person's right/left?