Practically every stroke forum I go to has persons commenting that stem cells are the only thing that will provide recovery for them. So far the only stem cell trials for the brain are in the safety stage, that is just to test that the stem cells do not cause problems. I see numerous problems that have to be considered and fixed before they can be considered successful.
1. If the cells are injected into the dead area they would need a blood supply and the cerebral spinal fluid would have to be moved out/absorbed.(angiogenesis)
2. Nothing would directly have the new cells take on the functions that used to exist in the dead area.
3. Injections next to the infarct but within a still working area would probably take on the functions that surround them. Neuroplasticity at work.
I believe that stem cells can generate enough cells to make up for the dead ones.
I know magical stroke recovery is the holy grail of stroke recovery but I don't think this is the solution. It may be helpful especially for smaller infarcts.
I won't make any comments on these except to say, read and ask your doctor.
World's first stem cell trial for stroke patients
Doctors have injected stem cells into the brain of a British stroke patient in the world's first trial of its kind.
ReNeuron gives update on stroke clinical trial
Information on Stem Cell Research from NINDS
Can Stem Cells Block Stroke Damage? Yes, but in a Surprising Way
Ischemic stroke treatment with stem cells
Recruiting patients April 2011
But this does make a powerful placebo, probably the same reason these nostroms worked in the 1800s.