>>> Robert Mcguire <[log in to unmask]> 05/28/97
10:57am >>>
what is pallidotomy? bob mcguire
[log in to unmask]
Robert -
From the 1930's through the early 1960's doctors used
surgical lesions in the pallidal regions [movement control
centers] of the brain to relieve some of the symptoms of
Parkinson's disease.
However, clinical research took the stage in the 1950's
and doctors discovered that the neurotransmitter dopamine
was involved in the symptoms of Parkinson's. Medical
therapy, L-dopa, became the treatment of choice.
After 10-15 years the doctors realized that L-dopa began
to lose its beneficial effect leading to adverse effects such as
dyskinesias (rigidity of muscles) and "on-off" fluctuations in
the patient's ability to move normally. Interest in surgical
interventions was rekindled in the 1970's.
New neurosurgical techniques using CT (cat) Scans, MRI
and PET scans allows surgeons to accurately target the
areas of the brain for a localized lesion of the ventral globus
pallidus - "Pallidotomy" - (usually uni-lateral: left or right side)
to alleviate movement disorders (severe tremors, rigidity and
bradykinesia/slowness) not treatable with medication.
Not all patients are candidates for the surgery. A patient
should not be suffering from dementia or depression and
must be "responsive" to levodopa therapy. The operation can
last up to 10 hours with the patient awake (the brain feels no
pain) except for local anesthetic and secured to a metal
frame on their head.
Some surgeons report an 80% reduction in dyskinesias
after surgery which allows patients to resume pre-operation
levels of medication, without adverse effects. Long term
effects of the procedure are still under evaluation.
Because the surgery involves the brain, a very tricky area
to operate in, adjacent motor areas for vison and movements
have been compromised in about 5% of the surgeries,
leading to blindness and/or paralysis.
Many neurologists feel that destroying more areas of an
already damaged brain is counter-productive. Rather, they
would like to implant and re-populate the dopaminergic nerve
cells in the brain caudate using embryonic nerve cells from a
fetal pig or human fetus. Data is too preliminary to make any
conclusions.
Stephan Schwartz <[log in to unmask]>
