EMBARGOED FOR RELEASE ON APRIL 16
WASHINGTON (April 16, 2007) - Researchers from the Cleveland
Clinic will present results of a study today that shows deep brain stimulation
(DBS) is associated with improvements on formal memory tests in patients with
severe psychiatric illness. Since 2001, this team of investigators has been
using DBS for treatment of obsessive compulsive disorder (OCD). At the 2006
American Association of Neurological Surgeons (AANS) Annual Meeting, they presented
findings which demonstrated that DBS results in significant improvement in
mood as well as reductions in anxiety, obsessions and compulsions in patients
with both OCD and treatment resistant depression (TRD).
The results of the current study, DBS in the Internal Capsule/Ventral
Striatum Improves Memory in Patients with Severe Psychiatric Disorders , will
be presented by Cynthia S. Kubu, PhD, 3:00 to 3:15 p.m. on Monday, April
16, 2007, during the 75th Annual Meeting of the AANS in Washington, D.C.
Co-authors are Hooman Azmi, MD, Benjamin Greenberg, MD, PhD, Donald Malone,
MD, Andre Machado, MD, PhD, Gerhard Friehs, MD, Steve Rasmussen, MD, Paul
Malloy, PhD, and Ali R. Rezai, MD. “Given the positive patient outcomes
in our earlier research, the team decided to undertake a new study analyzing
the effects of DBS on the cognitive symptoms of patients with severe psychiatric
disorders, ” stated Dr. Kubu.
An estimated 26.2 percent of Americans ages 18 and older - about one in four
adults - suffer from a diagnosable mental disorder every year, which equates
to approximately 57.7 million adults. While mental disorders are widespread,
severe psychiatric illness affects a much smaller number of people - about
6 percent, or 1 in 17. Mental illness can affect the functioning and thinking
processes of those who suffer, making daily tasks that most people take for
granted, very difficult, if not impossible.
DBS has been used to treat intractable pain for several decades. More recently,
use of this technology has proven to be a safe and highly effective treatment
for tremor and Parkinson’s disease with more than 35,000 DBS implants
worldwide. The applications for DBS therapy are expanding rapidly.
DBS involves the placement of small electrodes into deep brain structures
for the treatment of a variety of neurological and neuropsychiatric disorders.
The electrodes are connected via wires to an internal pulse generator (IPG)
that is placed in the chest wall. A magnet is used with the IPG to adjust the
stimulation parameters so that the appropriate level of stimulation is applied
at the electrode tip. The procedure is comparable to that of a cardiac pacemaker
in which the pacemaker helps maintain an appropriate cardiac rhythm. DBS is
presumed to help modulate dysfunctional circuits in the brain so that the brain
can function more effectively. DBS has several advantages over other neurosurgical
procedures in that the stimulation parameters can be adjusted to minimize potential
side effects and improve efficacy over time. Furthermore, the treatment is
reversible.
This research reports preliminary cognitive findings based on a series of
18 patients with severe psychiatric disorders (OCD n = 10, TRD n = 8) who underwent
placement of bilateral deep brain stimulating electrodes near regions known
to be important to emotional behavior. These regions of the brain also contain
fiber pathways that are known to be important to different aspects of thinking
(e.g., planning, attention, memory). All patients completed detailed testing
measuring a variety of thinking skills prior to and following surgery.
Significant improvements in the recall of prose passages were observed following
DBS in the internal capsule/ventral striatum . Furthermore, these improvements
were not related to the concomitant improvements observed in the patients’ underlying
psychiatric disorders. Thus, the improvements in memory do not appear to simply
reflect improvements in mood or OCD symptoms. No statistically significant
declines in thinking skills were observed following DBS in this region.
“The placement of DBS electrodes in specific motor and psychiatric
circuits in the brain has been shown to result in significant improvements
in the underlying movement or psychiatric disorder symptoms. Our current findings
suggest that DBS may also interface with memory circuits in the brain and result
in improvements in memory function in patients with severe psychiatric disorders,” stated
Dr. Kubu. “Clearly, these findings need to be replicated and more studies
are planned to further understand the results,” added Dr. Kubu.
Founded in 1931 as the Harvey Cushing Society, the American Association of
Neurological Surgeons (AANS) is a scientific and educational association with
more than 6,800 members worldwide. The AANS is dedicated to advancing the specialty
of neurological surgery in order to provide the highest quality of neurosurgical
care to the public. All active members of the AANS are certified by the American
Board of Neurological Surgery, the Royal College of Physicians and Surgeons
(Neurosurgery) of Canada or the Mexican Council of Neurological Surgery, AC.
Neurological surgery is the medical specialty concerned with the prevention,
diagnosis, treatment and rehabilitation of disorders that affect the entire
nervous system, including the spinal column, spinal cord, brain and peripheral
nerves.
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Media Representatives: If you would like to cover
the meeting or interview a neurosurgeon - either on-site or via telephone -
please contact the AANS Communications Department at
(847) 378-0517 or call
the Annual Meeting Press Room beginning Monday, April 16 at
(202) 249-4010.