New research has revealed the potential of adult stem cells to aid in stroke recovery. The new study suggests that injecting these stem cells directly into the brain can provide a chance for recovery even after a long period of time has passed following the stroke.
"We don't want to oversell this," said Gary Steinberg of the Stanford University School of Medicine and lead author of the study.
"This isn't the first stem cell trial for stroke, and we're in the early phase, with only 18 patients," he added. "But after injecting stem cells directly into the brain of chronic stroke patients, we were blown away."
The team examined patients that experienced severe motor deficits for six months or more who, prior to the study, had no promising options for treatment.
"After the injections we saw improvement in all 18 patients, as a group, within a month," Steinberg added. "Within days some were lifting their arms over their head. Lifting their legs off their bed. Walking, when they hadn't in months or years. The results were very exciting."
Each year, approximately 7 million people survive chronic strokes in the U.S., many of whom lose motor function and face the stark reality that it will never return.
"We're used to 90 percent or more of stroke recovery taking place in the first six months," Steinberg said. "So the thinking has been that we really can't restore function in chronic stroke patients because their circuits are dead."
The Stanford team examined patients with severe - but not extreme - stroke-induced impairment with an average age of 61, most of whom experienced their stroke at least one year before the start of the study.
With the patients under only a small amount of anesthesia, doctors drilled a small hole through their skulls and injected modified stem cells into numerous areas of the brain, all located near the site of the stroke.
After the experiment, all of the patients experienced significant recovery in motor control within the first month, with younger patients experiencing the best results. Furthermore, no significant blood abnormalities or side effects were observed.
"The results do sound amazing," said Ralph Sacco of the University of Miami's Miller School of Medicine who was not involved in the study. "But keeping in mind that everyone has long been looking for a miracle cure for stroke. It's really premature to draw conclusions. This is one very small study that was really set up to establish safety. More work will be needed."
The team is now planning a similar study on a larger sample of 156 chronic stroke patients to determine if the findings can be replicated on a larger scale.
The findings were published in the June 2 issue of the journal Stroke.
