 |
 |
----- 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. > > >