----- Original Message -----
From: Chris van der Linden <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, January 18, 2000 6:19 PM
Subject: Re: Neurosurgery- DBS


> Dear Donald,
>
> I recently posted my experience with 60 STN patients on this list. You may
> want to look in the archives for more information. I will "attach" (see
> below) the document for your convenience.
>
> Please don't hesitate to contact me for further questions.
>
> Best regards,
>
> Chris van der Linden, M.D.
> St. Lucas Hospital Ghent
> Belgium
>
> DBS in advanced Parkinson's disease.
>
> The hallmark treatment of Parkinson's disease is pharmacological.
However,
> chronic treatment with levodopa (Sinemet), frequently combined with
dopamine
> agonists (e.g. Permax, Parlodel) usually leads to motor complications such
> as wearing off effect, on/off phenomena and/or dyskinesias.  In addition
> gait disturbances and freezing become a real problem.  After many
> adjustments of medication dosages, the Parkinson patient is
> pharmacologically untreatable.  There remains  a condition, in which there
> is a very narrow window of a benificial clinical response.  At one end of
> the spectrum one finds severe off periods and on the other end an on
> response with severe invalidating dyskinesias.
>
> For decades, thalamotomy and pallidotomy have been an alternative
treatment
> for a selected Parkinson patient group.  However, with the introduction of
> levodopa in the early seventies, the surgical treatment became almost
> obsolete. Deep brain stimulation in Parkinson's disease was introduced
more
> than a decade ago, initially for the treatment of tremor (thalamic
> stimulation), later also for most of the other Parkinson symptoms
(pallidal
> and subthalamic stimulation).  The advantage of DBS is that this treatment
> is reversible, carries less risk for the patient and DBS parameters can be
> modified. A major advantage of DBS and in particular chronic stimulation
of
> the subthalamic nucleus (STN) is the effect on gait and freezing episodes,
> but also tremor.  In addition, the anti-Parkinson medication can be
reduced,
> which leads to improvement of the dyskinesias.
>
> From January 1996 until July 1997 37 patients received unilateral pallidal
> stimulation with marked improvement of tremor and dyskinesias.  For most
> other symptoms medication was required and frequently the dose needed to
be
> increased.   Therefore, in the summer of 1997 it was decided to stop
> pallidal stimulation and to change to subthalamic stimulation in patients
> with advanced PD in particular because other centers had good results in
PD
> patients with freezing and gait disturbances.  In addition, other PD
> symptoms, including tremor improved.
> From July 1997 I have been involved in STN surgery of 59 PD patients, 38
> males and 21 females, mean age 65 years. 11 patients had previous
unilateral
> GPi stimulation, who one to two years after GPi stimulation had severe
gait
> disturbances and freezing episodes.  The patients were selected on the
basis
> of freezing and gait disturbances with a otherwise good response to
> levodopa.  None exhibited dementing features as determined with
> neuropsychological testing. Patients with mild atrophy and
peri-ventricular
> white matter changes were accepted as candidates  Many patients had
> dyskinesias and reduced ADL scores.  After STN surgery, the medication
could
> be reduced on average by 50%, which probably is responsible for the
> reduction or cessation of dyskinesias in all patients.  Gait, freezing,
> rigidity, akinesia and tremor, if present, significantly improved in all
> patients.  Speech did not improve and worsened in patients, who already
had
> severe speech disturbances pre-operatively. The two year follow up of 14
> patients revealed similar post-op UPDRS scores to the 3 month post-op
> scores.  In these patients only minor adjustments of anti-Parkinson
> medication were necessary.
> The complications were minor. There were three hemorrhages, two cortical
at
> the level of the electrodes and one small brainstem hemorrhage at the
level
> of the oculomotor nuceus, which caused a transient diplopia. All three
> patients fully recoverd from their hemorrhage.  Transient post-operative
> confusion appeared in five patients lasting for several days.
>
> In conclusion, stereotactic STN surgery appears to be a very safe
procedure
> for patients with advanced Parkinson's disease, while the response to
> stimulation is remarkable for all PD symptoms, but in particular gait
> disturbances and freezing,  while anti-Parkisnon's medication could be
> reduced by at least 50%.  The effect is sustained at least two years after
> surgery.  STN surgery is a very could alternative treatment for patients
> with advanced Parkiosnon's disease.
>
>
>