White matter lesions, migraine and memory problems: a question and an answer

One of the readers of my blog wrote in with a question about white matter lesions on brain MRI. Her question and my response to it follows.


I was recently referred to a neurologist by my primary care physician for treatment of my migraines. While migraines have a been a part of my life, they have been occuring with greater frequency of late (10+ per month). To rule out any other cause of my migraines, the doctor ordered an MRI. The MRI revealed 20+ white matter lesions throughout my brain (various locations, various sizes). The neuro was at a loss as to why I had so many. I did inform him that approx 15 years ago I had unilateral ect, and asked if perhaps this had caused it? I also let him know that I was experiencing significant memory issues (forgetting short term and long term memories, and even blanking on spelling my own last name for a minute or two). I asked him if ect could be responsible? The neuro has since followed up with me and has stated that ect could NOT be responsible for the lesions, and was not likely to be responsible for my recent, memory issues. I have been tested for MS, lyme, infection, etc. – all negative. I do not suffer from depression or take any other medications which would cause memory issues. Any thoughts? What else could cause these lesions? Is these any research at all into lesions and ect? I am trying to get into Neuropsych testing to determine the extent of my memory loss. The migraines are now currently being sufficiently controlled with Imitrex.


Thank you for writing in to me M.  White matter lesions are commonly documented on brain MRI done for various reasons (in your case as a work up of migraines). The differential diagnosis of white matter lesions is broad and varies based on the age of the patient. In “most” adult patients especially those with risk factors for microvascular disease such as diabetes mellitus, essential hypertension (high blood pressure), dyslipidemia (high cholesterol), current or past heavy smokers these white matter lesions respresent small vessel disease (also referred to as microvascular ischemic small vessel disease). Meaning that the small blood vessels in the brain are showing signs of ischemia (lack of blood flow). So when I see extensive microvascular (small vessel) disease on a patient’s MRI scan of the brain what I worry about is the possibility of a stroke in the future. As a neurologist, I then try to identify his stroke risk factors and attempt to modify them. If he has high blood pressure and is not an on anti-hypertensive medication–start an appropriate anti-hypertensive, if he is already taking a blood pressure medication but the blood pressure is still not well controlled then I may need to increase the dose of his medication and/or change it. As per the new Joint National Commission guidelines broadly speaking the lower the blood pressure the better it is (earlier a blood pressure of 140/80 mm Hg was accepted as ” normal”, now we aim for level of 120/70 mm Hg). If the patient’s blood sugar is high (fasting blood sugar greater than 107mg/dl), I would investigate him for diabetes mellitus. For this blood sugar is tested in a fasting state and after meal (post prandial). There are normal values and if the patient’s blood sugar exceeds these normal values, then he has diabetes mellitus. Diabetes mellitus can be controlled by a combination of dietary modification, exercise, oral hypoglycemic medications (pills) and/or insulin injections. If the lipid profile is deranged (high total cholesterol, high low density lipoprotein, high triglycerides and low high density lipoprotein), then again dietary modifications, exercise and lipid lowering medications (statin group of medications such as Lipitor are one example) are recommended.

Now what do white matter lesions represent when they are seen in a young person (like for example in a  young lady 25 years of age)?  The main differential and what concerns most patients and physicians alike is whether this could represent multiple sclerosis. I have written about this before and again want to emphasize that the diagnosis of multiple sclerosis is a clinical one and not based solely on the MRI scan of the brain. The MRI scan always has to be interpreted after taking the history and examination findings into consideration. Also the white matter lesions of ischemic small vessel disease are different from the white matter lesions (plaques) of multiple sclerosis. In multiple sclerosis the lesions have a characteristic appearance and distribution in the brain.

White matter lesions can also be seen in many other infectious (Lyme disease is a good example) and inflammatory conditions (sarcoidosis, connective tissue diseases which cause vasculitis in the brain). Most of these diseases can be identified with the help of a good history and some basic tests.

White matter lesions are also commonly seen in people who suffer from migraines (more commonly seen in women migraine sufferers). Why do white matter lesions occur in migraine patients. While there are many theories of migraine pathophysiology, migraine is a vascular headache and hence the blood vessels are again involved.

Do white matter lesions cause memory problems. Now that is a tough question to answer. When I see extensive white matter disease in a brain MRI, it tells me about the health of the brain and the blood vessels. If a person has extensive white matter disease, the same pathology shall be seen in the blood vessels of the heart. So they are prone to both heart disease and brain disease (stroke, transient ischemic attacks). While Alzhemier’s disease is the most common primary dementia, vascular dementia is exceedingly common too. What is vascular dementia? As the name suggests, it is dementia (memory impairment, problems in multiple cognitive domains) caused due to multiple small strokes in the brain or rather strokes in a strategic location. These strokes occur over a period of time and may be clinically silent (meaning that the patient may not even realise that he has suffered a stroke). The small strokes over a period of time though add up and cause vascular dementia.

I hope this helps in answering some of your questions M. My advise to you is to follow up with your primary care physician and the neurologist. They shall help guide your work-up further.

Personal Regards,

Nitin Sethi, MD

Statins reduce risk of incident Alzheimer’s disease?

I recently read an editorial in the Journal of Neurology Neurosurgery and Psychiatryby Dr. Larry Sparks about statins and cognitive function. Multiple studies have hinted at reduced risk of incident Alzheimer’s disease with elective statin use. I thought this would be worthwhile to share with the readers of my blog and website (http://braindiseases.info).

As I stated above, multiple studies have linked a high fat/ high cholesteroldiet with increased risk of Alzhemier’s dementia. Hence many studies have been carried out to determine if lowering cholesterol levels with the use of statin group of medications (these are popular cholesterol lowering medications with names like atorvastatin (Lipitor), simvastatin (Zocor) among others) reduces the risk of Alzhemier’s dementia. While some studies have indicated a benefit others have provided contradictory results indicating little to no benefit on cognitive functioning.

As Dr. Larry Sparks states in his editorial there is likely a small subset of patients who will benefit from statin therapy. The trick lies in identifying these patients early on in their disease course from others in whom there is little or no benefit from statin therapy. Also it seems that some statins may be more beneficial than others when it comes to reducing the risk of Alzheimer’s dementia. This difference is likely due to their individual differences in blood brain barrier permeability (meaning to what extent they are able to penetrate the brain).

Till we are better able to identify this subgroup of individuals, there are certain things which we can implement in our own lives to tilt the scales in our favor. A low fat, low cholesterol diet should be encouraged. The cardiovascular (lowering the risk of myocardial infarction)and possible neurological benefits (with respect to possibly reducing the risk of incident Alzheimer’s dementia and stroke) makes this a very attractive proposition. Moreover this is a relatively cheap intervention. It though needs a comprehensive strategy to educate the public about the benefits of a low fat/ low cholesterol diet ( about the benefits of eating right {more vegetables, less of red meat and saturated fats} and incorporating a regular exercise schedule. People who already have cardiovascular risk factors like hypertension, diabetes mellitus and high cholesterol (dyslipidemia) should talk to their doctors about possible statin therapy.

I want to add that statins just like any other medication do have their own risk of side-effects. They thus should only be taken under the supervision of a physician.

The adage ” Eat right, live long and happy” still holds good!!! To that I would add ” EAT RIGHT, SAVE A BRAIN!!!”

Nitin Sethi, MD

Not quite dementia? red flags to watch out for

Not quite dementia?  red flags to watch out for

Nitin K Sethi, MD

Assistant Professor of Neurology

New York-Presbyterian Hospital

Weill Cornell Medical Center

New York, NY 10065

I get many patients who tell me during their office visit that they are worried they may be getting dementia. The thought of Alzheimer’s disease with its progressive neurocognitive decline and memory loss is a frightening thought indeed and patients are justifiably worried.

SO LETS GET DOWN TO THE BASICS. What are the red flags/ warning sings that you indeed do have Alzheimer’s dementia starting off?

Patients who have Alzheimer’s dementia are usually not aware that they have a memory problem. In the initial stages of the disease, social graces are maintained. These early patients may be able to hold down a job, socialize with friends and no one is aware that they have a memory problem.  Small problems may be starting off though. Losing keys, misplacing things, having problems with numbers, having problems balancing the cheque books and in counting change, forgetting names etc. As you can imagine these are not “major issues” and may not be noticed by the patient or family initially.

So usually when a patient hinself comes to me and tells me, he feels he may be getting demented, I approach it with a healthy dose of skepticism. Most of the times these patients do not have dementia, rather they may be depressed. Depression at times can lead to dementia like symptoms with loss of energy and drive and feelings of self-doubt. It is hence sometimes referred to as pseudo-dementia. You treat their depression and the patient feels much better and the memory problems resolve.

But when the patient is brought to my attention by a family member with complaints of memory problems, getting lost in the neighbourhood, change in personality, becoming indifferent to his personal appearance and grooming, apathy and lost of interest in activities previously enjoyed, in such patients the possibility of dementia crosses my mind.

One must remember that in dementias like Alzheimer’s disease (there are many different types of dementia), the problem is not just with memory. Dementias like Alzheimer’s disease affect a range of neuro-cognitive abilities. Thes patients have problems with language (we call this aphasia–there are many different kinds of aphasia), calculation, ability to sustain attention, ability of abstract thinking, of planning for the future (what I shall do next week) and in executitive functioning. They also suffer from what we call apraxias. Let me explain what apraxia is. Lets assume I can button and unbutton my shirt. Now this is a learned act, which I learned as a small child. Now suppose I get demented. Even though I am not weak (meaning the strength in my arms is intact), I forget how to button and unbutton my shirt. This loss of ability to carry out learned tasks despite intact motor/ muscle strength is called apraxia. Patients who have Alzheimer’s dementia forget how to tie their shoes laces, how to drive a car, how to eat with a spoon and so on. Hence in a way they become totally dependent on care-givers for all activities of daily living. Memory loss is just a component of a much bigger problem. Even when it comes to memory, they have problems in short term memory (what they ate for breakfast, who is the current President elect, whom did he defeat in the elections etc),  long term memory (what is your name, your wife’s name, your child’s name, where you were born, what date) may remain intact in the initial stages of the disease.

 So watch out for the red flags, not everything is dementia!!!

Tip of the tongue and “senior moments”: the truths behind dementia

Tip of the tongue and “senior moments”: the truths behind dementia

Nitin K Sethi, MD


        Comprehensive Epilepsy Center, Department of Neurology, NYP-Weill Cornell Medical Center, New York, NY (U.S.A.)


Address for Correspondence:

NK Sethi, MD

Comprehensive Epilepsy Center

Department of Neurology

NYP-Weill Cornell Medical Center

525 East 68th Street, York Avenue

New York, NY 10021

Fax: 212-746-8984

Email: sethinitinmd@hotmail.com

I read an interesting article in the Wall Street Journal by Melinda Beck titled ” The science behind senior moments”. In it she talks about “senior moments”-episodes where-in you are temporarily unable to recall a name, forget a number (like the telephone number of a close friend or a relative) or enter a room and forget what you were supposed to do. Just what do these “senior moments” represent-are they just signs of normal aging process or are they a warning sign of impending dementia?

Let me give you an example. Let us assume you are watching a movie starring Cary Grant. You see Cary Grant on the screen, you know who he is but for the life of you, you cannot recall his name. we call this the “tip of the tongue” syndrome. You have the name on the tip of your tongue but are unable to get it out. We all have older family members and friends. We notice that at times they are more forgetful. They forget their keys, forget names: are these “senior moments” or are they signs of dementia? Is there anything called senile dementia? (that is dementia occuring due to old age itself, not due to a neurodegenerative condition like Alzheimer’s disease).

Before we discuss this further, we should try to understand how memories are formed and stored in the brain. In simple terms we first register and encode memory, then this is stored and finally it is retrieved. What do i mean by this? Well the first thing which occurs is registration and encoding. For one to retain memory, one must first register what one is trying to remember. Let me explain this with an example. Lets assume you are reading a book. At the same time you are watching the TV and talking to your friend on the phone (that is you are multi-tasking). Now if I ask you to recall what you just read, it is possible that you shall not be able to do so well. Why? This is because your attention was divided and hence you never really registered what you were reading in the first place. If you did not register, you did not commit it to your memory and hence you cannot recall it. So first lession is that when you are trying to memorize something, make sure you pay attention.

Then comes consolidation and storage of memory, the process by which the brain stores the memory. Memory is usually stored in the temporal lobes and the hippocampus. This is a complex process and a lot is still not known how exactly are these memory programs laid down in the brain. Consolidation and storage of memory ensures that the memories become more permanent. There is some data to suggest that consolidation and storage of memory occurs at night while we are asleep. Maybe there is some truth to grandma’s saying of getting a good night sleep before a big examination.

Finally is the process of retrieval. This is the process by which we are able to recall an old memory. One can have a problem at any step of this memory process. Patient’s with Alzheimer’s dementia usually have a problem with both consolidation and retreival. Someone who is intoxicated but does not have Alzhemier’s dementia like an alcoholic shall have problems with encoding as he is delirious.

Now that we know how memory is formed, I want to stress that the tip of the tongue syndrome occurs in many healthy people. Why does it occur? Why is there a temporary memory block which then clears by itself and we are able to remember everything? No one quite knows the answers to these questions.

Senior moments though (especially if they are occuring in the senior population above the age of 65) deserve a more closer look. Is the problem episodic (comes and goes) or is it constant (always present)? Is is static and stable or is it progressive? Does it involve just one domain of memory (like names) or is it more widespread involving multiple domains (not just names but things like forgetting how to drive a car, problems with calculations and abstract thinking etc).

If the above are present, then it is not senior moments and is more likely to be dementia. Some neurologists doubt if something like senile dementia actually exists. We all have met some elderly people with razor sharp memory.

That in essence is the truth behind senior moments and the tip of the tongue syndrome.