Parkinson's disease is a chronic, degenerative neurological disorder that affects one in 100 people over age 60. While the average age at onset is 60, some people are diagnosed at 40 or younger. There is no objective test, or biomarker, for Parkinson's disease, so the rate of misdiagnosis can be relatively high, especially when the diagnosis is made by a non-specialist. Estimates of the number of people living with the disease therefore vary, but recent research indicates that at least one million people in the United States, and more than five million worldwide, have Parkinson's disease.
Parkinson's disease was first characterized extensively by an English doctor, James Parkinson, in 1817. Today, we understand Parkinson's disease to be a disorder of the central nervous system that results from the loss of cells in various parts of the brain, including a region called the substantia nigra. The substantia nigra cells produce dopamine, a chemical messenger responsible for transmitting signals within the brain that allow for coordination of movement. Loss of dopamine causes neurons to fire without normal control, leaving patients less able to direct or control their movement. Parkinson's disease is one of several diseases categorized by clinicians as movement disorders.
The exact cause of Parkinson's disease is unknown, although research points to a combination of genetic and environmental factors. If a continuum existed, with exclusively genetic causes at one end and exclusively environmental causes at the other, different Parkinson’s patients would likely fall at many different places along that continuum.
In the past 10 years, researchers have identified a number of rare instances where Parkinson's disease appears to be caused by a single genetic mutation. In these cases, the mutated gene is passed from generation to generation, resulting in a great number of Parkinson's disease cases within an extended family. On the opposite end of the continuum, in the early 1980s, a group of heroin users in California took drugs from a batch contaminated with a substance called MPTP. After ingesting this chemical, the drug users were stricken with a form of Parkinson's disease that was primarily, if not exclusively, "environmental" in origin.
For most Parkinson's patients, the cause lies somewhere in the middle. While many Parkinson’s patients report one or more family members with the disease, it is not always clear that one or several genes are the cause. Similarly, while some patients suspect that exposure to one or another chemical or environmental toxin caused their Parkinson’s disease, this also cannot be conclusively proved. Scientists currently believe that in the majority of cases, genetic and environmental factors interact to cause Parkinson's disease. Research into this subject continues aggressively every day. Unfortunately, however, it is generally impossible to determine what specifically caused an individual's Parkinson’s disease.
The causes of Parkinson’s disease are unknown, there is no scientifically validated preventive course to reduce the risk of its onset. The single biggest risk factor for Parkinson’s disease is advancing age. Men have a somewhat higher risk than women.
That being said, a number of studies have highlighted factors that are associated with either greater or lesser risk of Parkinson's disease. For example, smoking and caffeine consumption have been associated with lower rates of Parkinson's disease, while head injury and pesticide exposure have been associated with higher risk. While such studies do not definitively link these factors with Parkinson's disease one way or another, they highlight areas where further research may guide us to risk-prevention or treatment strategies.
The cardinal symptoms of Parkinson's disease are resting tremor, slowness of movement (bradykinesia) and rigidity. Many people also experience balance problems (postural instability). These symptoms, which often appear gradually and with increasing severity over time, are usually what first bring patients to a neurologist for help. Typically, symptoms begin on one side of the body and migrate over time to the other side.
There is no objective test (such as a blood test, brain scan or EEG) to make a definitive diagnosis of Parkinson’s disease. Instead, a doctor takes a careful medical history and performs a thorough neurological examination, looking in particular for two or more of the cardinal signs to be present. Frequently, the doctor will also look for responsiveness to Parkinson's disease medications as further evidence that Parkinson's is the correct diagnosis. (However, starting on medication right away can limit your ability to participate in clinical trials that urgently need newly-diagnosed Parkinson’s patients.)
Indian doctors with training in brain conditions (neurologists), brain surgeons (neurosurgeons), doctors with training in mental conditions (psychiatrists), pain specialists, specialized programming nurses and other specialists use an integrated team approach to treating people who have deep brain stimulation. Indian specialists have successfully used deep brain stimulation to treat hundreds of people who have essential tremor, Parkinson's disease and dystonia. Recently, doctors have used DBS to treat people who have cluster headaches, Tourette syndrome, epilepsy and chronic pain that hasn't responded to other treatment.
Neuro specialists in India use computer-assisted brain surgery, intraoperative MRI and awake brain surgery during deep brain stimulation.
Indian Neurologists are ranked among the Best surgeons for neurology and neurosurgery worldwide. Because the brain can shift slightly during surgery, there is the possibility that the electrodes can become displaced or dislodged. This may cause more profound complications such as personality changes, but electrode misplacement is relatively easy to identify using CT.
After 2–4 weeks, there is a follow-up to remove sutures, turn on the neurostimulator and program it.
Deep brain stimulation surgery technique involves implanting electrodes inside the deep nuclei of brain called as subthalamus under local anesthesia. These electrodes are then connected to IPG (Pacemaker) implanted underneath the skin below the clavicle through the connecting leads under general anesthesia. To perform any kind of activity, the patient has to switch on the device with the help of a patient programmer. This stimulates the deep brain nuclei, which results in improvement of all the symptoms of Parkinson disease.
With the progress of disease the parameters of stimulation are changed over a period of time so that patients can remain symptom free for long period. The patient himself can change the stimulation parameters with the help of patient programmer. Normally the life of the pacemaker is five years and after that a new pacemaker replaces it. The electrodes remain in position for life long.Rechargeble Pace makers are now available that can be recharged at home.The life of these pace makers are 15-20 years.The stimulation of subthalamic nucleus through this device leads to improvement in all the symptoms of advanced Parkinson disease.
DBS uses a surgically implanted medical device, similar to a cardiac pacemaker, to deliver electrical stimulation to precisely targeted areas within the brain. Stimulation of these areas blocks the signals that cause the disabling motor symptoms of Parkinson's disease. The electrical stimulation can be noninvasively adjusted to maximize treatment benefits. As a result, many individuals may achieve greater control over their body movements.
DBS System consists of three implanted components :
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- Lead – A lead consists of four thin coiled insulated wires with four electrodes at the lead tip. The lead is implanted in the brain.
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- Extension – An extension connects to the lead and is threaded under the skin from the head, down the neck and into the upper chest.
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- Neurostimulator – The neurostimulator connects to the extension. This small, sealed device, similar to a cardiac pacemaker, contains a battery and electronics. The neurostimulator is usually implanted beneath the skin in the chest below the collarbone (depending on the patient, a surgeon may implant the neurostimulator in the abdomen). Sometimes called a "brain pacemaker," it produces the electrical pulses needed for stimulation. These electrical pulses are delivered through the extension and lead to the targeted areas in the brain. The pulses can be adjusted wirelessly to check or change the neurostimulator settings.
The doctor may advise few antibiotics to prevent infection. The patient may need to visit the doctor several times after the surgery to adjust the stimulation with the help of programming. The doctor may prescribe a detailed medication plan to the patient. The patient should take some precautions after the surgery and follow the instructions given by the doctors. He/she should take care of the incisions and the surgical region on the head, by keeping it dry and covered. Heavy physical activities and lifting heavy weights should be avoided for few weeks after the surgery. Regular follow-up with the treating doctor should be done.- »
- In this surgery we do not injure the brain so it is relatively risk free.
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- Completely reversible and programmable
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- Parkinson medications are reduced which results in improvement of drug related side effects.
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- There is improvement of quality of life in both off and on stage of the disease.
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