A small but significant study in the U.S. has found that a treatment which was designed to clear blocked carotid arteries and prevent stroke has also improved brain function.
The researchers report that almost half of patients who were treated with a carotid stent to prevent a stroke showed statistically significant improvement in brain function, such as memory, judgment and reasoning.
Doctors insert the tiny wire-mesh tubes, the carotid stents, via a small puncture in the groin and thread them through the blood vessels directly into the carotid artery in the neck.
The study which involved 37 patients found that 16 patients or 43 percent showed improved brain function a year after the stent was implanted, but doctors saw cognitive improvements as early as three months and the gains continued when checks were carried out at six and 12-month intervals.
Lead researcher Dr. Rodney Raabe, chief of radiology at Sacred Heart Medical Center in Spokane, Washington, says many of the patients have returned to a level of function they thought they had lost.
For the study the researchers conducted a two-hour battery of 11 standard neurocognitive tests normally used to assess patients believed to have a degree of dementia such as Alzheimer's disease.
According to experts the study confirms what they have already observed and they say it supports a fair amount of anecdotal evidence.
The carotid arteries are on either side of the neck and are the main blood conduits to the brain.
Almost one third of all strokes can be attributed to clogged up carotid arteries and every year, about 700,000 Americans have a stroke with a third of that number dying.
Stroke the third-leading cause of death in the United States.
As a rule most patients with blocked carotid arteries will have surgery to clear the blockages, but carotid stents offer a less-invasive alternative to the problem and are a blessing for patients for whom surgery is a high risk option.
Surgery involves a neck incision of up to seven inches.
The recently approved carotid stent is used to provide a structure to the diseased vessel after doctors inflate a tiny balloon in the artery to move fatty deposits against the artery wall.
The flexible stent helps to keep blood flowing to the brain while a tiny net-like filter traps any fatty deposits dislodged during the procedure that could cause blood clots.
At present the risk of stroke with either surgical or less-invasive stenting procedures is between 4 to 10 percent, depending on the patient,which say experts prohibits doctors from treating patients to improve brain function unless they are at risk of a stroke.
Several studies have looked at brain function after surgery, with mixed results.
The findings were presented at the International Symposium on Endovascular Therapy (ISET).