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Test only. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > PALLIDAL STIMULATION FOR PARKINSON'S DISEASE=20 > > > PREFACE > > This text was written by Geert Ari=EBn, the first (young) Parkinson patient= > (38 years old), in Belgium who received a pallidal-stimulation. By the= > operation Geert was delivered from his rigidity, slowness, tremor and= > involuntary movements. At the same time Geert could reduce his Parkinson= > medication to the half...A new life can begin ! > > > "By this way I want to express my profound gratitude to Prof.Dr. Jacques= > Caemaert (neurosurgeon ), Dr.Chris Van der Linden (neurologist) and Dirk= > Caestecker (Medronic-Belgium) for their total dedication and their valuable= > advices during my stay in the University Hospital in Gent. > At the same time I want to thank all the people of the departments= > Polyclinic Neurology and Admission Neurosurgery for the love and the= > friendship that I could experience. > > My second message of thanks goes to Jean Clement. Jean is Parkie and helps= > me by the translation of great parts of this article.Thanks, Jean. > > To all Parkies who are going to walk the same way, I want to say this : We= > all know the suffering which we have to experience day by day. Parkinson's= > disease is a sickness that ties us more or less to this earthly life...But,= > as is often the case in many things which are concerned with living and= > suffering, sunshine comes after rain. Admission to the hospital means a= > bit of suffering. But I am convinced that this little bit of suffering= > (rain) is worth while in view of what comes next, namely Sunshine...Merely= > this tought keeps you upright during your stay in the hospital...Be sure of= > one thing: if we all go together hand-in-hand on the way, we will win the= > fight against Parkinson's Disease in the near future... > > > My war-cry remains meanwhile: > > "TO HELL WITH PARKINSON " > > > Tuesday, the 6th of February 1996 > > Geert Ari=EBn > Kapelsesteenweg 135 > B-2180 Ekeren > > (Tel.:03.644.02.50) > > > > > > > PALLIDAL STIMULATION FOR PARKINSON'S DISEASE > > > Prof.Dr.J.CAEMAERT (neurosurgeon Univ.Hosp. Gent), Tel.:.09.240.32.56 > Dr.C.VAN DER LINDEN (neurologist Univ.Hosp. Gent), > Tel.: 09.240.45.29 > Dirk CACAESTECKER (Medronic-Belgium) > Tel.: 02.460.20.55 > > > > 1. What is Parkinson's Disease ? > > Parkinson is a disease which finds its cause in the brain and is sometimes= > also called shake-paralysis. > It is not known how one gets Parkinson. Parkinson is not hereditary,= > mortal or infectious. > There are three major symptoms of the disease : shake (tremor) stiffness= > of the muscles (rigidity),slowness of movements (bradykinesia). > Fatigue is often the result of these manifestations because each movement= > becomes slower and more difficult. Very often you have to think about the= > way in which you will perform a movement and sometimes you feel as if you= > were carrying a block of lead. Besides, due to the tremor, the muscles are= > permanently active. The shaking gets worse under stress conditions or when= > attention is attracted to it. > Most parkinsonians walk with short steps while bending forward. This may be= > due to the stiffness of the muscles. Many Parkies have problems with their= > handwriting that is often wriggly. The greatest problem is that at one= > moment you can do a lot of things and at the next moment none. People in= > general do not understand this and find you a poseur. > > > There are still another number of symptoms, although there are as many= > manifestations as there are patients. Some are very slow, others are hyper= > mobile. Many patients have a fixed facial expression which gives the= > impression that they are always angry, infatuated or depressif. There may= > be complaints about swallowing, constipation, slow piddling, excessive= > perspiration and excessive saliva. > > > All these symptoms are caused by the loss of certain cells in the brain,= > with as consequence an insufficient production of the chemical dopamine.= > The progression of the disease goes along with the decrease of the dopamine= > production. > Dopamine is produced in that part of the brain called the substantia nigra= > (black substance).=20 > > > > > > > > > Dopamine is a link in the chain of neurons: brain-spiral= > marrow-nerves-muscles. > The activity of dopamine has an indirect effect on the nerve pathways which= > go to the spiral marrow and the muscles. If there is only a little= > activity, then the activity to the spiral marrow will also be disturbed.= > Neurons and muscles are not in direct contact with each other; they need a= > (neuro)transmitter substance such as dopamine. In case that there is not= > enough production of transmitter, other substances, such as acetylcholine,= > will have the upper hand, causing a disturbance of the balance followed by= > the appearance of symptoms as in Parkinson's Disease. > > Once the loss of cells in the substantia nigra begins, there is no recovery= > possible. The brain is not becoming "better". However the loss of cells can= > be slower by one patient then by another. > > > Treatment with drugs remains symptomatic. Many patients show side effects= > due to the use of drugs. Others complain that the drugs are ineffective or= > nearly so. > > > There has been done some work to find solutions to reduce the breakdown in= > the brain. > Many years ago operation techniques which brought some relief were already= > available. As far back as the 1940's stereotactic thalamotomy (tomy means= > cut trough) was being performed as a treatment for tremor. Stiffness and= > slow movements were not affected by this operation. Some 25 years ago this= > operation technique was abandoned in favour of the introduction of the= > wonderdrug L-DOPA (levodopa). This drug opened indeed new perspectives for= > many Parkies. Treatment with levodopa relieved all the symptoms of the= > disease and doctors thought that the disease was cured. Unfortunately, time= > has revealed that this is not the case. Patients only get good relief of= > symptoms for five to ten years. Then the patients become extremely= > sensitive to the drug so that after they take it the patients get abnormal,= > extra movements called dyskinesias. =20 > These dyskinesias can be by themselves disablend. When the activity of the= > drug wears off, the patients get symptoms of Parkinson's Disease that are= > worse than if they had taken no medicine at all. > > > 2. History of pallidotomy for Parkinson's disease > > Pallidotomy was introduced in 1952 by Dr.Lars Leksell and was successful in= > relieving many Parkinsonian symptoms in patients. At the same time,many= > surgeons were performing surgery on the thalamus and for a variety reasons,= > thalamotomy became widely accepted, replacing pallidotomy as the surgical= > treatment of choice for Parkinson's Disease. Thalamotomy,which has an= > excellent effect on the tremor, was not quite as effective at reducing= > rigidity. In addition, bradykinesia was often aggravated by the procedure.= > =20 > > > In 1985, Dr.Lauri Laitinen, who had worked with Leksell, > re-introduced the pallidotomy, as a treatment for patients who had= > previously undergone thalamotomy but remained symptomatic. Many of his= > patients suffered from severe bradykinesia, rigidity, tremor and other= > unusual involuntary movements.These patients had long standing, severe= > Parkinson's Disease that had been treated with medications for many years= > and exhibited what is known as drug-induced dyskinesias. He reported his= > first pallidotomy series of 38 patients in January of 1992 and found that= > 80-90% of patients had a long lasting relief of symptoms. This encouraging= > experience prompted other specialists to re-examine the role of= > pallidotomy. > > Science evolves from day to day. Today we have made so much progress that we= > can start with pallidal stimulation. Pallidal stimulation is in contrast= > with pallidotomy a reversible operation. This means that -in the hope that= > Parkinson's Disease will be cured in the near future- the stimulator and= > the probe which is on the target in the pallidum can be removed by a rather= > simple operation. > > > On simple demand a video of the operation can be obtained by Dr.C.Van der= > Linden (neurologist at the University Hospital in Gent) > =20 > 3. What are the effects of pallidal stimulation ? > > It is the aim of pallidal stimulation to reduce or keep under control the= > Parkinson's symptoms, as there are rigidity (stifness), tremor (shake),= > bradykinesia (slowness) and dyskinesias (involuntary movements caused by= > Levodopa). At the same time pallidal stimulation makes it possible to= > reduce in a large measure the anti-Parkinson medication. > > > 4. Who is a candidate ? > > -The method is probably most beneficial for the Parkinson patient who had in= > the beginning a good response from L-dopa therapy, but who later on= > developed "ON-OFF" fluctuations > that were difficult to manage with medication. (if you say "I am ON",this= > means that you feel allright thanks to the Parkinson medication ; being OFF= > means that your medication is no more active. In such a situation you feel= > muscles becoming rigid, movements becoming slower and tremor developing). > > -It is not a reasonable alternative for patients who can keep their symptoms= > fairly well under control with the usual anti-Parkinson drugs. > > -It is not indicated for patients who suffer from loss of memory, = > confusion or lack of orientation. > > > > > > -Parkies who want to undergo a pallidal stimulation should stay realistic.= > At its best the operation cannot cure Parkinson's Disease. Even patients= > with a serious reduction of their symptoms, still need an anti-Parkinson= > medication. > > > Now that this new technique is available, we wonder whether we should= > indeed wait untill the last moment to perform the operation !!!= > Particularly young patients can become useful and may function quasi= > normally in society... =20 > > > > > 5. Operation Procedure=20 > The patient is under sedation, but a general anesthesia is not needed by= > this method. This makes feedback possible during the operation so that the= > chance of complications is reduced. > > The new technique, which has become available only in the last= > years,provides in a local stimulation in the pallidum internum from a= > device similar to a "pacemaker". A thin wire probe is inserted permanently= > into the pallidum internum in a stereotactic manipulation similar to that= > for pallidotomy. The (sophisticated) battery (with a life of 3 to 5 years,= > dependend of the stimulation frequency) is placed under the skin of the= > patient's chest. The electrical signals can be switched on and off with a= > small magnet held close to the device. If the Parkinson symptoms fluctuate= > in the course of the day, then the stimulus can be adjusted. The battery is= > replaced through a simple skin incision. > Probes can be implanted on both sides of the brain, and the side effects are= > far fewer than those caused by pallidotomy. The long-term effects are not= > yet known. (with thalamic stimulation there are 4 years of experience).=20 > The 2 pallidal stimulations performed by Prof.Dr.J.Caemaert (neurosurgeon)= > and Dr.C.Van der Linden (neurologist) in January 1996 showed the dramatic= > reductions in tremor, rigidity, bradykinesia and dyskinesias in patients= > (one of 38 years and one of 61 years) who had been treated by this surgical= > method. > Both patients could reduce their medication to the half. =20 > > > 6. Is pallidal stimulation dangerous ? > > Stereotactic pallidal stimulation is not without certain risks altough major= > morbidity (post-operative harmful consequences) and mortality (death as= > consequence of surgery )is less than 1% (available statistics about= > thalamic stimulation). > One side effect has been a contra-lateral visual field defect. This defect= > of the visual field, named scotoma, creates a blind spot in the lower= > visual field. If this occurs on the left side it is generally well= > tolerated, but on the right side it may disturb reading.=20 > > > The incidence of this side effect and other potential side effects are= > minimized by intraoperative physiologic testing during the procedure.= > Stereotactic pallidal stimulation is not painful. The surgical target= > within the pallidum is defined by a CT and/or MRI scan carried out with a= > special stereotactic frame (Leksell frame )attached to the head. Once the= > appropriate target coordinates have been selected on a computer station,= > the patient is taken back to the operating room for the surgical procedure= > itself. The headhair is shaved and the surgery is carried out under= > intravenous sedation. A 3 cm skin incision is made in the scalp after= > infiltration with local anesthesia. Next a hole of about 1 cm is drilled= > through the skull (a handbore is less frustating than an electrical one). > A 1.8 mm insulated stimulating electrode is then introduced under impedance= > monitoring into the postero-ventro-lateral globus pallidus. The target area= > is stimulated with very small electrical impulses which may give rise to a= > variety of different reactions. The purpose of the stimulation is to make= > sure that the probe lies in the correct area of the pallidum. With= > electrical stimulation, tremor and rigidity can be reduced almost= > immediately in the operating room and this confirms accurate placement of= > the electrode tip. Electrical stimulation may also give rise to visual,= > motor, sensory or other untoward symptoms and this would indicate that the= > probe may need repositioning. If symptoms occur even after repositioning,= > there is a risk that the surgery cannot be performed safely and that the= > test probe has to be removed without possibility of placing the= > definitive electrode. When the intraoperative stimulation indicates that= > the tip of the test electrode lies in the optimal location, then the= > neurologist (who knows his patient very well) can begin with a detailed= > intraoperative testing to insure that no neurologic deficit will be= > incurred when placing the definitive electrode. It also will allow for= > assessment of beneficial effect on tremor (shake), rigidity (stiffnes), and= > bradykinesia (slow movements). If all of this conditions are met, then a= > permanent electrode is inserted at the chosen location. During the= > insertion of the final electrode, the patient will be given a variety of= > motor, visual and psychological tests to check that no adverse effects= > develop.If unexpected reactions are observed further inserting of the= > definitive electrode is stopped immediately. It should be noted that= > neither the test stimulation, nor the implanting of the definitive= > electrode are painful. Post-operatively the patient is observed in the= > recovery room for approximately one hour and then returned to his hospital= > room. He may eat and drink immediately after the surgery and is often able= > to leave the hospital in a few weeks. The hypokinesia, rigidity and= > dyskinesia generally improve immediately. Sometimes the tremor does not= > disappear immediately but gradually diminishes over several days to= > weeks.If the surgery is successful without side effects, no special= > post-operative care or training is required. Stitches can be removed one= > week after surgery. Headache in the post-operative phase is minimal and can= > be kept under control. > > > 7. The protocol > > The appropriate selection of Parkinson's patients for surgical treatment= > implies a thorough presurgical evaluation by the operation team= > (neurosurgeon and neurologist). The protocol includes a detailed history= > and physical examination as well as videotaping of the patient's= > preoperative condition. A Uniform Parkinson's Disease Rating Scale is also= > administered along with a variety of other rating scales. = > Neuropsychological testing and neuro-imaging is carried out as needed= > (MRI,PET scanning). This preoperative evaluation is important to ensure tha= > the patient is a good candidate for surgical intervention. Many of these= > scales and tests will be performed post-operatively, to assess the results= > of surgery in an objective fashion.=20 > =20 > > > > > > > > > > > > > > > ?? > > > > =20 > > =20 > > > > --=====================_762363309==_-- >