SURGICAL TREATMENT OF PARKINSON’S DISEASE
What is Parkinson’s disease and what kind of a condition is it?
Parkinson’s disease is roughly characterized as a condition influencing deeply localized structures of brain (also referred as basal ganglion) and it accounts for a substantial part of symptoms of movement disorders. Movement disorder refers to shivering (tremor) particularly in arms and legs, body stiffness (rigidity) and decrease in velocity of movements (bradykinesia). Tremor leads to very severe and stressful life for the patient, while rigidity and bradykinesia prevents independent mobility of the patient. Inability to get out of the bed, severe body contractions and spasm, inability to manipulate objects held by the patient (i.e., drinking water, eating meal using spoon), inability to walk without support and very slow walking may be observed when the disease is at advanced stage.
How is the treatment?
Treatment of the disease involves medications and surgery. Principal active substance of medical treatment is dopamine. Dopamine levels reduce due to cerebral damage and it is replaced with drugs which may relieve findings of the disease at early period. If complaints may regress with medications, surgery is not required. However, surgical treatment is performed if resistance occurs against drug over the time and if drug-related movement disorder develops. It should be kept in mind that surgical treatment of Parkinson’s disease is a matter of team work. Patient is necessarily examined by neurologist in pre-operative period and later, patient is referred to the neurosurgeon for operation. Postoperative follow-up of the patient is undertaken by same team.
What is the aim of the surgical treatment?
There are various very small nuclei which are located at deep layers of the brain (subthalamic nucleus, ventral intermediate nucleus and pallidal nucleus). When a procedure influencing appropriate ones of those nuclei is performed, improvement will be obtained with respect to tremor, bradykinesia and rigidity. Activity of nucleus can be hindered via two methods. First method involves accessing and damaging the relevant nucleus. A permanent damage is induced in the nucleus with this method. The second method involves following procedures; a battery-operated electrode is placed into those cerebral nuclei and the battery is usually implanted beneath clavicula. Stimuli are generated by the battery and the stimuli prevent activity of the nucleus where the electrode is placed and thus, an effect is obtained without causing permanent damage. Another advantage of this method is that rate of effect can be adjusted in the postoperative period using remote control of the battery. The procedure involving a battery and electrode system is referred as DEEP BRAIN STIMULATION.
How is surgical intervention made?
First, patient undergoes a specific MRI study since it is necessary to image those nuclei. The nuclei cannot be imaged with ordinary MRI protocol. After specific MRI protocol is completed, a stereotactical frame is placed on the head of the patient and later, computerized tomographic imaging is performed with frame cap in place. The images obtained with stereotactical frame in place are transferred to computer software and coordinates of those nuclei are mathematically calculated thanks to the frame. Operation is started based on resultant coordinates. First stage of the operation is performed under partial anesthesia and thus, the patient is still awake at this stage. Electrodes are directed to the relevant nucleus using specific parts mounted on the previously placed stereotactical frame. A small hole drilled on skull will be sufficient for this procedure. While those electrodes are directed to the very small nucleus (size in mm), recording is made using those electrodes and most intense activity region of the cell is determined; the region is stimulated and the stimulus will be used to determine if tremor and rigidity regress. Patient is communicated and frequently examined during intra-operative period. While all those procedures are time-consuming, they are important to get healthiest outcome. Optimum region of the very small nucleus is selected and electrode is placed accurately to this point to ensure that the patient gets maximum benefit… Second stage of the operation starts when optimum electrode position is ensured. This stage is shorter and procedures are performed under general anesthesia. Free ends of electrodes, which are placed into brain, are connected to the battery which is implanted to the subcutaneous region. Patient is followed-up for 1-2 days under inpatient settings.
When is brain battery operated?
Battery can be activated approximately in postoperative day 3 or 4. Battery parameters are adjusted in periodical visits throughout first several weeks in postoperative period and the final adjustment is made when optimum yield is obtained. Life of the battery is approximately 5 years and there is no need to repeat electrode insertion into skull to replace the battery. Only main battery compartment is opened and expired battery is removed and later, new battery is placed with a brief operation.
How much benefit is gained by patients?
If patient is well eligible for operation, efficiency will range between 40 percent and 90 percent. The efficiency rate of 40 percent implies that a patient with inability to dress and undress without support may wear garments without any support. Very mild residual tremor in single hand of patient who experienced insufferable tremor and attending control visits by walking with spouse in his arm despite inability to walk without support of spouse due to stiffness in the past are examples of priceless happiness for both patient and physician.
What are risks of the operation?
They can be addressed under three titles. Risk of intra-cerebral hemorrhage secondary to the operation is below 1 % and a portion of the bleeding episodes may threaten life. Vessels are examined on all slices with preoperative radiological imaging and a course distant to those vessels is preferred to reach the nucleus. Moreover, if this rare event occurs, it can be immediately diagnosed with early postoperative imaging study and it can be intervened. Anesthesia risk is valid for any and all types of operations. Here, preoperative assessment is to avoid this risk. A significant part of the operation is anyway under partial anesthesia and the small remaining portion is under anesthesia. Infection risk is also rare. It may be necessary to extract the system if infection develops.
What are characteristics of Parkinson’s disease? Treatment methods
Although Parkinson’s disease is known as disease of advanced age, it may occur in young population. Incidence of the disease is above the known rate. The deformation of nuclei, which are also referred as basal ganglions, in the brain of patients with Parkinson’s disease leads to tremor, rigidity and bradykinesia. When all those symptoms combine, patient may not drink water or eat meal with spoon due to tremor and may not move due to rigidity and may not walk due to bradykinesia. Therefore, Parkinson’s disease is manifested as a dramatic disease which directly influences life quality of the patient. At early period, those symptoms can be successfully eliminated, while efficiency of drugs will reduce over the time and side effects will emerge leading to onset of insufferable disease. Neurosurgery department plays role at this stage of the disease. Some very small regions of the brain are determined and the nuclei are accurately targeted; when electrode is placed to the target region, improvement can be ensured in symptoms of the disease by sending electrical stimuli over the electrode. This procedure is referred as “Deep Brain Stimulation”. Also known as brain battery in the colloquial speech, surgical treatment of Parkinson’s disease will cause improvement in tremor, rigidity and bradykinesia and thus, the patient will significantly feel relieved.
Equipment and targeting required for Parkinson surgery are very important. Knowledge and experience are as important as the infrastructure. It is highly important to make fine adjustment of the battery in the postoperative period. Neurosurgery Department of Medicana Hospitals had performed Parkinson surgery in 30 cases within approximately one year. Many centers worldwide may reach such figures only in many years.
How much benefit is gained by patients in the postoperative period?
Ability of a patient to wear dresses alone who could not be wearing dresses alone, very mild residual tremor in single hand of patient who experienced insufferable tremor and attending control visits by walking with spouse in his arm despite inability to get out of the bed due to the rigidity are all indicators of the fact that the patients get significant benefit in the postoperative period. Preliminary processes of the Parkinson’s disease operations which are performed at Medicana Hospitals Both radiological imaging and medical equipment infrastructures were taken into account when the infrastructure required for surgical treatment of Parkinson’s disease was established at Medicana Hospitals. The process progressed under supervision of academicians and physicians of neurosurgery department and operations are successfully performed.
How is the attitude of the people to this operation? Do you have patients who reside in other cities?
This operation can be performed in very limited number of healthcare centers in our country and the operation bears remarkable costs on patients although a part of charges is paid by social insurance institution. Cost of the operation is reduced by Medicana Hospitals to the level which is affordable by most people. Thus, surgical treatment of Parkinson’s disease is now very qualitatively performed and affordability is also increased resulting with better access.