Lybrate.com has an excellent community of Neurologists in India. You will find Neurologists with more than 34 years of experience on Lybrate.com. You can find Neurologists online in Chennai and from across India. View the profile of medical specialists and their reviews from other patients to make an informed decision.
Book Clinic Appointment with Dr. Sridharan Ramaratnam
Treatment of Neurological Problems
Treatment of Nerve And Muscle Disorders
Treatment of Paralysis
Cerebral Palsy Treatment
Brain Tumor Surgery
Electroconvulsive Therapy (Ect) Treatment
Surgery Of The Facial Nerve
Radiofrequency Neurotomy Procedure
Spine Surgery Treatment
Traumatic Brain Injury (Tbi) Treatment
Treatment of Traumatic Brain Injury (Tbi)
Assistive Walking Device Training
Vagus Nerve Stimulation ( Epilepsy )
Submit a review for Dr. Sridharan RamaratnamYour feedback matters!
I'm a 17 year old girl and I suffer from frequent mild headaches that stays for long. I feel giddy everyday when I lie down or sit down for a while and suddenly get up to some to go somewhere. I've been said that i've got migraine and I wear spectacles. What should I do?
I am asking for my Father. His age is 73 years History: Left side paralysis - June 2006. 10 Years back Regular medicine: Tab. Tozaar 25: 1-1 Tab. Atormac 10: 0-1 Tab. Antiplar plus: 0-1 Recently on 25th Oct 2016, he is diagnosed with 6th nerve palsy. His right eyeball can move upper, lower and left side but unable to turn on right side. Sometimes he is facing the problem of double vision. MRI reports shows normal. Doctor has prescribed below medicines Tab. Neutrogem 800: 1-1 Tab. Nueromin plus: 0-1 Tab. Elirab DSR: 0-1 Tab. Solubet: 1-0 Here I request you to 1) please check whether the treatment is going on right track? 2)Whether I need any investigation/ check up? 3) How many days required for recovery?
My age is 31 due to stress and work load I feel a lot of weakness inside and my hands shiver I feel sexually weakness also m not able to give my 100%.
I have migraine headache from my 14 age I am not able to bear that pain Doctors told no proper treatment for this If any suggestions please inform.
I had a C-sec recently & I'm experiencing abnormal pain in my upper thighs. I can't sleep on my sides. Please suggest me what to do. Also I'm developing insomnia, is it because I'm feeding my baby till late night? Please tell me what must I do?
I am 67 years old I am diabetic for last 10 years. I take one glucored forte daily. Sugar is under control. I get numbness and pain in feets and palms what should I do?
My mother is suffering from insomnia and some time she have headache and gas problem in stomach then what is the guidelines for solution of these disease.
I am 21 year old male having migraine pain, besides medicines what should I do or what should be my routine so that it will not cause severe pain, also please suggest me some yogas for the relief of my migraine pain.
Hello doctor I am feeling full right arm numbness and pain (mild) from last one month. Both Numbness and pain are not continue kindly suggest what to do.
I have migraine and its like severe headache and it causes vomiting too after complete vomit I feel better and headache get disappear also I am suffering from cough since my childhood and chronic sinusitis patient too. Kindly help me. Thank you.
I feel like my left brain isn't working. My consciousness is also low. I have problem thinking continuously.
I had an accident in which there was a minor head injury. Hairs at the injured lost have permanently lost. How can I grow them again.
I am a 26 years old male working as software engineer having migraine from past 1 and half year. I consulted doctor and he gave me course for 1 month and it went fine. But its is not permanently cured. He suggested me to take neapon tablet when I get headache. Can you please give me solution for permanent cure? thanks in advance.
Nowadays I can't able to inserting thread into needles or pulling elastic rubber so hard as my hand and fingers trembling shaking whenever I try to focus on it. Please help me.
* Should I be afraid of talking to the doctor?
No. Every doctor wants his/her patient to recover as soon as possible. If patients have the right knowledge, they are able to interpret and report their symptoms better. Having this knowledge prevents unnecessary anxiety and greatly facilitates diagnosis and treatment.
It is the duty of every doctor to provide the right information to the patient, and every doctor tries to do this to the best of his/ her ability. Sometimes it is not possible to provide thorough information and answer all questions of a particular patient, because then the doctor will not be able to give adequate time to the next patient. Th is is the main reason behind writing this book. In many cases, patients do not want to talk to their doctor because they are afraid of knowing more about their illness. This is the wrong approach. Knowledge is power. I assure you that having the right knowledge will decrease your anxiety and help you get better.
I do have one suggestion: before going to the doctor, write down all your questions on a piece of paper. Almost all doctors will be very happy to answer your questions if you ask them efficiently.
* Why should I pay attention to my symptoms? just run some tests and you will know what disease I have...
Tests can be helpful, but they cannot diagnose all diseases. Often, no test can detect the small short-circuits in the brain that are responsible for causing seizures. Until very recently, there was absolutely no test that could diagnose parkinson's disease. Tests cannot tell the doctor how you are responding to the medication. For example, in parkinson's the doctor may ask you how you feel in the morning, how long the eff ect of medication lasts, do your arms or shoulders jerk after you take medication, and so on. Each symptom is important for the correct diagnosis and treatment of your condition. You and your immediate family members can provide the doctor with this essential information. If you have difficulty remembering your symptoms, you should note them in a notebook. If you have difficulty describing some of your symptoms, you should make a video recording for 3-5 minutes using a smartphone or digital camera (android, Iphone etc). Such recordings are tremendously helpful for diagnosis and treatment.
* What are the common tests used to diagnose brain diseases?
The three tests most commonly used are:
Mri, ct scan and eeg. Other specific tests have been described in the relevant chapters.
(i) Mri (magnetic resonance imaging) scan:
An mri scan is probably the most important test for diagnosis. It can diagnose many diseases such as a stroke, tumor and inflammation. Mri scanning is done in a big tube shaped machine which is attached to a bed. Th e patient sleeps on the bed for 30-45 minutes. Th e bed slowly moves back and forth through the machine. During this time the machine clicks very detailed pictures of the patient's brain.
Please note that during the scan you may hear some loud whooshing and clicking sounds. Th ese are just the sounds of
Magnets and motors inside the machine, and there is no need to be concerned by these noises. Some people may feel anxious because of the small space within the scanner, and a few people may need medications to decrease this anxiety. Mri scanning is extremely safe; there is usually no health risk. Before the scan, please inform the doctor about any metal inserts or implants (e. G. Heart defi brillator) In your body.
Mri test machines are of various strengths such as 1.5 tesla, 3 tesla and so on. Mri machines with a higher number (for example 3 tesla) take better pictures. This book was written in 2015, at this time the highest resolution mri available in india was 3 tesla.
(ii) Ct (computerized tomography) scan:
The CT Scan machine looks just like the mri machine. It has a bed that moves back and forth slowly while the machine takes a picture of your brain.
CT scan has a few advantages over mri:
(i) It is less expensive. An mri may cost around 5000-7000 rupees, while a ct scan usually costs around 1000 inr (indian rupees).
(ii) It can be done very quickly. An mri may take 1 hour or more, but a ct scan can be completed in 10-15 minutes.
Unfortunately, CT scanning has some significant disadvantages:
- The picture obtained by a ct scan is not as clear as that obtained by an mri. The difference in quality is striking: it is like the diff erence between a black-and-white tv from the 70s and the new lcd televisions available today.
- CT-Scan exposes your body to radiation.
Radiation is bad for your body, and especially a baby's body. Therefore, pregnant women should never have a ct scan. Ct scan is commonly used during emergencies. When a patient comes to the emergency room, a rapid ct scan may be done to look for emergencies which may need immediate surgery such as bleeding inside the brain. An mri is usually done the next day, when the patient is more stable.
If you have already had an mri, then usually you do not need a ct scan. Th ere are a few rare conditions (e. G. Calcification in brain) which are seen better on a ct, but these are very uncommon.
(iii) Eeg (electro-encephalo-graphy):
Our brain functions because of electric currents traveling from one place in the brain to another. An eeg measures this electric current.
To do this test, small pieces of wire are stuck to the head using glue. These wires are then connected to an amplifi er and the electrical activity in the brain is recorded. The machine itself does not send any current to the brain. It only records current. Therefore, there is no pain or discomfort, and this is an extremely safe test. Anyone can have this test, including pregnant women, babies and very sick patients. Th is test is most often used for evaluating seizures. An eeg is also used in cases where the patient is unconscious for a long time, without a clear reason.
1. Doctor, my hand keeps shaking. It stops shaking only at night. Why is this happening?
The shaking of your hands is called a tremor. There are many causes of hand tremor. Th e most common causes are essential tremor and parkinson's disease. If you have essential tremor, your hands will shake more when you try to do something. For example, writing may become very diffi cult or water may fall down when you try to drink form a glass.
If you have parkinson's disease, the tremor is maximum when your hands are resting and doing nothing. For example, when you are sitting on a chair and watching tv comfortably, the hand starts shaking. Besides these common causes, there are other causes. For example, shaking of the hand (s) can begin after a small stroke near an important part of the brain called the red nucleus or in a condition called dystonia which causes contraction of the hand muscles without any clear reason some medications (see list), severe anxiety and very excessive tea/coff ee can cause hand shaking. Finally, there are diseases that have symptoms exactly like parkinson's disease.
Therefore, I need to examine you carefully. Based on observing you so far, I think there is a possibility that you may have parkinson's disease.
2. Parkinson's! I have heard this is an extremely serious illness! is this disease fatal?
No. Parkinson's disease is not fatal. Yes, but it is important to treat parkinson's disease promptly. Th e diagnosis of parkinson's disease is often missed. If not treated on time, patients with parkinson's disease are significantly restricted in their day-to-day activities, practically becoming disabled if treatment is delayed for a long time.
Secondly, if left untreated, patients with parkinson's disease can have frequent falls causing serious injuries including fractures and head injuries. Hence the diagnosis and treatment of parkinson's disease should be done as soon as possible.
3. What causes parkinson's disease?
Our brain runs on electricity and chemicals. If there is too much or too little of a particular chemical in your brain, it causes a disease. Parkinson's disease is caused by the reduction of a chemical called dopamine in our brain.
Dopamine is produced in the back of our brain, in a part called the mid-brain. It is then transported forwards and is widely distributed throughout the entire brain. It fi res up the movement centers of our brain, and helps them communicate better with one another. In parkinson's disease the cells in the midbrain producing dopamine gradually
Die. No one quite understands why this happens. Then effect is that the movement centers of the brain don't Communicate well with one another, and this produces the various symptoms of parkinson's disease.
4. Ok so what are other symptoms of parkinson's?
You already know one symptom shaking of the hands while resting. There are many other symptoms in patients with parkinson's disease and recognizing them is often very easy:
- Their muscles are often stiff and become inflexible, but they often do not complain about it. Th ey may complain that they are not able to do some things such as comb their hair.
- They are very slow in doing everything. They walk very slowly. They often bend forward while walking.
- They have difficulty turning around when they are walking.
- Sometimes they can get stuck in one position. Often this happens while walking, but may happen while doing something else.
- In later stages, they can fall frequently.
- Their friends may notice that their face has become expressionless and they just appear to stare off without blinking into distant space.
All patients do not have all of these symptoms. Some patients experience just the shaking of hands; other people experience just the muscle stiffness and so on. Often as people get older, more and more of the dopamine producing cells are destroyed and patients start developing more symptoms. But it takes years for this to happen and it may not happen in all people. In some patients, parkinson's disease remains restricted to just a few symptoms.
5. Ok doctor, thankfully I seem to be having just the hand shaking at this time. But other than the symptoms you just described, I am having other symptoms. I am always constipated, I cannot sleep well, and my saliva keeps dribbling from my mouth. Is it possible that these symptoms are also related to parkinson's disease?
Yes. It is not just possible but very likely that all these symptoms are due to parkinson's disease. Parkinson's disease is recognized by all doctors as a disease affecting movement. But in addition to movement problems, patients can have many other problems.
These are frequently not recognized, even by physicians, and therefore left untreated. If recognized and treated (and simple treatments are available for many of these symptoms), their resolution can significantly improve the patient's quality of life. It is important that your doctor should think about other diseases too. For example
If you have back pain, it is important that the doctor should think about arthritis of the back, if you have impotence your doctor should think about diabetes etc. But in many cases, no other cause can be found - these problems are due to parkinson's disease. About 10-20 years ago, even doctors did not know about these complications of parkinson's disease. It is a matter of great pride for me that I had the opportunity to receive training from the world-famous indian professor who is at the forefront of research regarding these symptoms: Dr. Kallol ray chaudhuri at king's college hospital in london.
6. How can you be sure that I have parkinson's disease?
A better patient history and examination will help me to confirm my diagnosis. We need to rule out other problems which look like parkinson's disease. Certain drugs may produce symptoms that are very similar to parkinson's disease (see list). Make sure you are not taking these medications, and avoid these medications in the future.
There are a few other diseases which have almost the same symptoms at parkinson's disease. Their names are complicated! these include diseases such as progressive supranuclear palsy (psp), multiple systems atrophy (msa) and cortico- basal degeneration (cbd)! th names are not very important the important thing is that there are other diseases that look just like parkinson's disease. Some of these diseases are identified by your doctor by looking for small clues on your exam: such as your blood pressure and the way your eyes move. Now let me tell you something very frankly even after a very detailed history and meticulous examination, the diagnosis may not be clear in some patients, even to the best of doctors in the best of institutions.
7. So isn't there a test for parkinson's disease?
Unfortunately, there is no test for parkinson's disease which can prove it with 100% accuracy. An mri (see information for everyone section) can be helpful to rule out some other diseases e. G. Multiple strokes, and
Therefore many doctors get an mri in patients with parkinson's disease. There is one test that can be helpful. It
Is called the dat scan. The dat scan is abnormal in parkinson's disease, but it is also abnormal in some other diseases that look like parkinson's disease! therefore it is helpful only in certain cases. There are a few other tests like a cardiac scan (mibg scan), but these are only available at a few research centers, and again, do not help to completely rule out other diseases.
8. But. That is very concerning. What you are saying is that in some patients the diagnosis remains unclear?
You are correct. In most cases, the diagnosis of parkinson's disease can be made with certainty. But about 10% of patients have an uncommon mixture of symptoms so that no doctor, no blood test, no investigation can confidently determine if the patient has parkinson's disease or if he/she has another, similar disease. In such cases, most doctors explain the situation to the patients, and give them anti- parkinson's medications such as levodopa. Usually, a dramatic improvement is seen if the patient has parkinson's disease. If a patient takes an adequate quantity of Levodopa for 4-6 weeks and there is no clinical improvement, it is very unlikely that he has parkinson's disease.
These medications cause clinical improvement in about 1/3rd of all patients with the other diseases such as msa, psp etc. However, this improvement is not as dramatic as the improvement seen in parkinson's disease and frequently does not last as long. As the years go by, other symptoms develop (such as urinary problems, eye movement problems and falling) and a more definite diagnosis can be made on the basis of repeat examination.
9. Hmm. Doctor, there must be several medicines for parkinson's. If the parkinson's is caused by a lack of dopamine, shouldn't consuming dopamine help to reduce the symptoms of the parkinson's?
Yes, there are many medications and yes you are correct providing extra dopamine to the brain is one of the best ways to make the symptoms better. I have provided a list of these medications, but it is worth highlighting two of them: levodopa is the oral form of dopamine. It is converted into dopamine when it goes inside the brain. Th is is usually the fi rst medication that is started. It is available in standard, dispersible and extended-release
Preparations. Young patients with very mild symptoms of parkinson's disease are given a diff erent kind of medication initially. These medications are called dopamine agonists. Th ere are 3 dopamine agonist medications: pramipexole, ropirinole, and rotigotine. Th ey are available in standard and extended release preparations.
10. So, what you are saying is that the dose of parkinson's medications does not stay constant throughout life?
You are correct. Parkinson's disease often progresses as patients grow older. Some symptoms change and become less prominent but on the whole the symptoms become more severe. Th is progression is probably caused by gradual death of more and more cells producing dopamine. Very few people have side eff ects due to these based on the symptoms that develop, the medications. Often, parkinson's disease dose of parkinson's medication may need progresses as patients grow older and new to be changed, or new medications may be given. For example, if you have trouble sleeping at night, then the doctor can ask you to take an extra levodopa pill at night or an extended release ropnirole pill. If the benefi cial effect of levodopa is not lasting for as long as it used to, the doctor may ask you to take entacapone with the levodopa. If you have constipation the doctor will prescribe a laxative and so on. Sometimes it may take a few trials of different medications over 1-2 weeks to find the right combination that works for you. Parkinson's is not a deadly disease. Th ere are many medications for parkinson's. Th e doctor needs to have precise information about the patient's symptoms in order to prescribe the right medications. In parkinson's disease, the doctor needs help from his/her patient. It is essential to record your symptoms accurately and visit your doctor regularly, every 3 to 6 months.
11. Doctor, you are saying that frequently the dose of levodopa needs to be increased. But what happens if too much levodopa gets into the person's brain?
Yes, this can happen but it is not life-threatening. When there is excessive dopamine in the brain, the body starts moving too much. Often there are small jerks in the neck, shoulders and sometimes in the leg. If you are a fan of michael jackson, you have seen break-dancing. Th ese excessive movements look like break-dancing. Th e medical term
For these excessive movements is dys-kinesias. It is very important for you to be aware of them and remember the word: dys-kinesias. Often, dys-kinesias are at their maximum 1-2 hours after you take levodopa. If you have trouble recognizing these movements, you should take a video of any suspicious movements on your smartphone and show it to your doctor. In the early stages of parkinson's disease, dys-kinesias are only seen when the
Levodopa dose is very high. But in more advanced stages, they may be seen at lower doses and giving the patient an adequate dose of levodopa without producing dyskinesias may become diffi cult. At this stage, some dyskinesias may need to be tolerated. If you are suff ering from dyskinesias, you can reduce the dose of levodopa that you are
Taking. But this may result in some of the symptoms of parkinson's disease (slowness, rigidity, freezing etc) to reappear. Another way in which dyskinesias may be reduced is by giving you amantadine.
12. I am getting it now, doctor. This is like a weighing scale isn't it? too little levodopa causes the parkinson's disease symptoms to come back, and too much levodopa action causes dyskinesias.
Yes! th at is absolutely right. In the initial stages, balancing this weighing scale is very easy. But after 10, 15 or in some cases 20 years, balancing this scale becomes diffi cult. After taking levodopa, many patients improve but also get dyskinesias. It becomes impossible to fi nd a levodopa dose that causes improvement without producing dyskinesias. Th erefore, at this stage, some dyskinesias may need to be tolerated as long as you are able to function satisfactorily.
13. So doctor, you told me what happens when there is too much dopamine action in the brain. What if the there is too little dopamine action in the brain? What if levodopa just stops working?
Levodopa never stops working. But it may become less effective, and its effect may become short-lived. Th ere could be many reasons for levodopa to become less eff ective. These are listed separately the most important reason is that the patient may not be taking the levodopa on an empty stomach. As parkinson's disease advances, the eff ect of levodopa lasts for a shorter duration of time. Here is a somewhat typical story from such a patient. Remember, this happens only in few cases:
Taking the tablet helps me only for a short time. When I wake up in the morning, my feet contract, twist and become painful.
14. I understand. It must be difficult at that stage to find the right combination of medications. What if the situation worsens further?
Yes. And I think it is vital for patients to understand this. Frequently, with the right combination of medications the patient can get better. But it can take some time to find the right combination; sometimes even 3-4 trials of diff erent combinations may be required. If a patient gives up hope and gives up in the middle of these trials, the only possible outcome is progressive deterioration of the patient's health.
Sometimes, inspite of repeated adjustments, a good combination of medications cannot be found. But remember this situation arises 10-20 years after the parkinson's symptoms have been detected. Many parkinson's
Patients do not have to face this situation. If the right combination of medicines could not be found even after many trials, then still there is one solution. Brain surgery. Th en I take my morning dose of levodopa
And feel good. Sometimes I get some dyskinesias, but I don't complain about them because I am feeling good. But only an hour or 1.5 hours later, the symptoms of parkinson's disease start coming back. I become slower and slower, and then freeze. I get better again when I take levodopa, but I can't keep taking levodopa every hour!
I understand. It must be difficult at that stage to fi nd the right combination of medications. What if the situation worsens further?
Yes. And I think it is vital for patients to understand this. Frequently, with the right combination of medications the patient can get better. But it can take some time to fi nd the right combination; sometimes
Even 3-4 trials of different combinations may be required. If a patient gives up hope and gives up in the middle of these trials, the only possible outcome is progressive deterioration of the patient's health. Sometimes, inspite of repeated adjustments, a good combination of medications cannot be found. But remember this situation arises 10-20 years after the parkinson's symptoms have been detected. Many parkinson's patients do not have to face this situation. If the right combination of medicines could not be found even after many trials, then still there is one solution. Brain surgery. A proper mixture of medications may help this situation as well. I had given you an
Example of this earlier: entacapone can prolong the eff ect of levodopa.
15. Doctor. Brain surgery? are you kidding me? this is a big deal. By the way, what is this surgery called?
I know brain surgery is a big deal. This surgery is called deep brain stimulation, or this is a brain surgery, but a relatively dbs
If your symptoms are well controlled with medications, no doctor in their right mind would recommend you to have surgery. But in a few patients, medications no longer produce adequate improvement. Either the improvement lasts for a very short time, or the medication produces such dramatic dyskinesias that giving an adequate dose is impossible.
Approximately, 70% of such patients benefit from this surgery. The improvement is very significant, but dbs does not make all symptoms of parkinson's disease magically disappear. It is very important to have realistic expectations from the surgery. The improvement seen after surgery is batteries last for about 5 years, and can be Replaced when required.
16. Well. How is this surgery done?
This is a brain surgery, but a relatively minor one. A metal frame is usually attached to the patient's head. A very small hole (approximately 1 cm in diameter) is made in the head, and a thin (1 to 1.5 mm thick) wire is inserted through it. The wire is pushed into a very particular part of the brain called the sub-thalamic nucleus. Th e same process is repeated on the other side and another small wire is inserted. These wires are then connected to a small battery (a square of approx. 3 inch) that is kept in the skin below the chest. No part of this device can be seen from the outside, and any scars on the head are usually covered by hair in a few weeks. Th e device is usually turned on 4 weeks after the surgery. On an average, most.
17. I see. Doctor, does DBS cure all symptoms of parkinson's disease?
No. DBS surgery improves only those symptoms which improve after levodopa.
- Dbs surgery prolongs the eff ect of levodopa, decreases dyskinesias, improves slowness of movement, hand shaking, muscle stiff ness and in general makes the patient much more functional. However, symptoms that do not get better after levodopa such as freezing and falling usually do not get better after dbs.
- Approximately 5% of patients can have serious complications such as stroke, seizure and infection. But most of these problems are cured with medications. Only 1% of these patients have permanent problems from these complications, such as permanent weakness of one side of the body. Other symptoms that we talked about e. G. Sleep problems may get better after dbs. I conducted an audit of sleep symptoms after dbs during my time in london at king's college hospital, and found that there is
Significant, but non-dramatic, improvement in many patients.
Two problems can become worse after DBS:
(i) Severe psychiatric problems such as severe depression and hallucinations and
(ii) Severe diffi culties of thinking and memory. If any of these problems are severe, dbs is usually not off ered to the patient. If a patient has severe psychiatric problems and is under treatment, dbs may be considered in the future if they completely resolve.
18. Okay doctor, what are the risks of this surgery?
Th ere is a small amount of risk involved in any surgery. Since dbs surgery is relatively minor, the risk is low but is not non- existent.
- The risk of death is less than 1%
- Approximately 5% of patients can have serious complications such as stroke, seizure and infection. But most of these problems are cured with medications. Only 1% of these patients have permanent problems from these complications, such as permanent weakness of one side of the body.
- A few patients have minor problems such as problems in wire connections or a non-functioning battery. Th ese are easily corrected. In short, about almost 90-95% of patient do not have any complications during or after the surgery, and the risk of death or permanent problems is very small (lts 2%).
19. Can the doctor guarantee a significant benefi t after DBS surgery?
No. No doctor in the world can guarantee Improvement after dbs. Th at being said, improvement happens in most patients as long as they are carefully selected. Before off ering you option of surgery, the doctor will give you a large dose of levodopa and make sure that your symptoms improve significantly. He/she will tell you that this is the maximum benefit that you may get after dbs, and try to set realistic expectations so that you are not disappointed after the surgery. Often the surgery is followed by a period of temporary improvement, even before the battery is switched on. This improvement Goes away in a few weeks. Th is is expected and you should not be disappointed - this is a good sign. After the battery is switched on, it may take between 3-6 months to achieve the optimal balance between your dbs and medications. During this time, your symptoms will improve gradually. But you should be patient if your symptoms
Have not improved within 1-2 months there is a good chance they will improve with further dbs adjustments. Most patients improve after dbs surgery, but a few people do not improve. Th e reason why these people do not benefit from dbs surgery is unknown, and this is being vigorously researched in the us, uk and other countries. Read more here