NEW YORK, Jan 04 (Reuters Health) -- By targeting pinpoint beams of
radiation to specific brain areas, researchers say they have reduced seizure
activity in epileptic rats.
The procedure, called stereotactic radiosurgery, might someday become "a
new or complementary surgical treatment" for epilepsy in humans who do not
respond to drug treatment, explain investigators led by Dr. Yoshimasa Mori of
the University of Pittsburgh, Pennsylvania. Their findings are published in the
January issue of the journal Neurosurgery.
According to the research team, previous studies have suggested that the
focused beams of radiation aimed at the brain regions involved in epilepsy might
"reduce or abolish seizures" in humans.
Investigating further, Mori and colleagues treated epileptic rats with
various doses of radiosurgery over a period of 6 weeks.
The researchers report that during the last 2 weeks of therapy, 7 of 8
rats (87%) treated with the highest dose of radiation showed no signs of
epileptic activity on electroencephalogram (EEG), compared with 6 of 20
untreated rats (30%). Seizure activity ceased in about 50% of rats treated at
lower doses.
According to the study authors, low- or moderate-dose radiation therapy
appears to suppress the brain cell signaling that triggers epileptic seizures.
At higher doses, the treatment appears to cause the "destruction of (nerve)
pathways" important to seizure activity, they report.
In all but the highest dosage attempted, radiosurgery caused no damage to
healthy surrounding brain tissue. Based on these findings, Mori's team believes
that moderate levels of radiosurgery might provide humans with safe but
effective seizure control.
But the investigators stress that "longer-term studies in more animals are
warranted" before the therapy can be tested in humans.
