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"The brain...spoils and rusts". Certainly a striking
image, but a dark one. Its rather like being hit with
a truck when you read it as early in the AM as I am. I
think I was actually struck speechless for a moment,
especially after all the posts yesterday re: cognitive
impairment vs. dementia. Poetic license or do you feel
that damaged by the disease?    Carole H.


--- William Harshaw <[log in to unmask]> wrote:
>     Reflections on Therapy
> for
> Parkinson's Disease:
> Medication and Neurosurgery
> by
> Bill Harshaw
>
> Parkinson's Disease is associated with free radicals
> which in turn are
> associated with the deposition of iron.  The human
> brain is encased in fat.
> For a person with Parkinson's, the brain, which is
> the source of the highest
> creativity and reasoning, spoils and rusts
>
>  The two procedures I had - the pallidotomy in 1993
> and deep brain
> stimulation the following year - are much in the
> news as Parkinson's
> patients search out possible ways to mitigate their
> symptoms and improve the
> quality of their lives.  Media accounts of these
> procedures focus on the
> successes, sometimes spectacular, and give less
> coverage to the patients
> whose lives have not increased in quality.
>
>  Neurosurgery as a therapy for Parkinson's disease
> continues to be both
> experimental and controversial. Pallidotomy,
> thalamotomy, deep brain
> stimulation and foetal transplants haven't yet
> reached the status of bypass
> surgery for cardiac patients - the gold standard.
> But it is useful to
> remember that they are all based on what the noted
> American physician Lewis
> Thomas calls ‘halfway technologies'.He does not use
> this term derisively,
> but to point out that they do not represent a cure,
> only better symptom
> management.
>
>  Foetal transplant surgery is to the doctors an
> extension of the current
> ‘gold standard' of treatment, ‘dopamine replacement
> therapy', as represented
> by the L-dopa based medications.   However, it has a
> number of ethical and
> moral hurdles to clear before  becoming acceptable
> to society generally.
> The other procedures fall into the general category
> of what surgeons do
> best: "if its broke, fix it" (with apologies to Bert
> Lance).
>
>  To put neurosurgery in the context of the universe
> of treatment for
> Parkinson's it is important to remember that
> pallidotomy and thalamotomy
> have been around for fifty years.  They were the
> therapy of choice for
> advanced PWPs.untl the mid 1960s when L-dopa was
> discovered to be
> efficacious.  As L-dopa gained acceptance, its
> superiority to all other drug
> therapies became apparent.  Neurosurgery went into
> eclipse, not to have a
> renaissance for a quarter century, a period which
> saw the development of two
> generations of a new type of drug - dopamine
> agonists - which increase and
> prolong the effectiveness of L-dopa.
>  A quarter century's use of L-dopa as the medication
> of choice demonstrated
> its superiority in symptom management; it also
> revealed the drug's
> shortcomings - dyskinesia and psychiatric
> side-effects in advanced patients
> who were on high doses being among the more
> significant.. In the early
> 1990s, technological advances, the miniaturization
> of surgical instruments,
> a more nuanced and comprehensive understanding of
> neuroanatomy, a new era in
> neuroimaging and the need to provide some sort of
> relief to advanced
> patients led  to a renewal of interest in
> neurosurgery - the old operations
> being done more successfully and with greater
> precision and the invention of
> DBS by Alim Benabid and his colleagues in Grenoble
> France.  Almost
> paralleling the surgical innovation was the
> development of a third
> generation of agonists which, if they live up to
> their press releases, will
> provide a meaningful advance on current drug
> therapy.  The procedures and
> the drugs are at the limit of human knowledge.
>
>   Foetal transplantation is considered separately.
> As a class of surgery,
> it belongs with organ transplants - heart, lungs,
> kidney ... the list goes
> on.  It first showed its face in the late 1970s and
> has been developing
> quickly since then.  At times the pace of progress
> seems slow to patients,
> but the rate of change of progress has been nothing
> short of exponential.
> Results of a recent double blind study are every bit
> as good as were
> expected and parallel the results of other the types
> of surgery   .
>
>  Comparing the state of therapy for Parkinson's
> today to what it was a mere
> quarter-century ago, the progress is staggering.
> Before L-dopa, the
> medications available were a variety of drugs which
> were serendipitously
> found to be beneficial as therapy.  They were really
> pretty primitive. Now,
> there is L-dopa, three generations of agonists,
> neurosurgery and a whole new
> array of research projects, any one of  which has
> the potential to advance
> treatment markedly.
>
>  It should be noted that every therapy has its
> drawbacks, called side
> effects, which range from the trivial to the
> serious.  Some of these side
> effects are major enough to prevent certain patients
> from using some
> therapies.  Indeed, there is a website on the
> internet devoted to patient
> accounts.
>
>  The implications of these advances on a broad field
> of new and newly
> adapted drug and surgical therapies is that
> physicians will have several
> arrows in their quiver when presented with a patient
> with symptoms that
> previously would have been intractable.  The other
> aspect is the hope that
> these developments engender.
>
>  The American philosopher John Searle noted in a
> 1995 article:
>
> As far as we know the relevant processes take place
> at the micro levels of
> synapses, neurons and cell assemblies.  All our
> conscious life is caused by
> these lower level processes, but we have only the
> foggiest idea of how it
> all works.
>
> The doctors know that lesioning works and that
> chronic stimulation works,
> yet they do not know how or why.  That should give
> some cause for pause.
> The same comment can be made, to a degree, with
> respect to drug therapy.  We
> don't know why some drugs are  more effective than
> others.
>
>  Perhaps Parkinson's disease will, in the end, be
> found to be not one
> condition, but a cluster of conditions with several
> common characteristics
> and each one having unique properties which set it
> apart.  The existence of
> progressive supra-nuclear palsy and multi-system
> atrophy are two cases in
> point.  That is why it is a very good thing that
> there are half a dozen
> agonists on the market and three types of surgery -
> lesioning, stimulation
> and transplant. One agonist or type of surgery may
> be more effective than
> others in different varieties of the condition.
>
>  Research is also yielding results on discovering
> the causes of Parkinson's.
> PD is caused by the death of the cells comprising
> the substantia nigra which
> produce dopamine.  It is not known what causes the
> cells to die.  The
> prevalent current hypothesis is the so-called
> ‘double hit' theory - which
> seems to be the case with other neurodegenerative
> conditions as well - an
> hereditary or genetic predisposition which can be
> hit by an environmental
> toxin, thus providing the double hit.  The toxin
> could be anything from
> pesticide and fertilizer to industrial pollutants
> and
=== message truncated ===




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