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Head space: Finding a way to do 3D surgery on the brain

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Surgeons carry out operations on the brain using 3D technology

 

When Avi Yaron was 26 years old he had a motorbike accident – a day he describes as the luckiest of his life.

As doctors scanned his head to check for damage, they found a tumour deep inside his brain which may otherwise have remained undetected.

And in 1993 the electronic engineering student from Israel was told the mass they had just discovered was nestling close to areas of the brain critical for movement and thought.

He now faced a choice – to have complex, invasive surgery that carried a risk of paralysis, or to find another way.

After a year of searching, Mr Yaron came across a surgeon in New York who removed part of the tumour successfully, and samples showed it was benign. The engineer was then advised to wait until technology had improved enough for the next operation to be less risky.

But for Mr Yaron this was not an option. The possibility remained it could put pressure on parts of the brain as it grew.

He said: “I was young and thinking of starting a family. I could not be passive about this sword hanging over my head.”

After five years of seeking out key surgeons and experts in technology, Mr Yaron had the rest of the tumour removed during a conventional operation – with good results.

Picture of operation using 3D glasses
The whole team wears 3D glasses and watches the surgery unfold on screens in the operating theatre

But this epic search for better surgical options continued to play on his mind. He kept thinking of and experimenting with ways to do brain surgery in a less invasive way.

And over the last few years he perfected a way to do surgery on the brain – in 3D.

Surgery through a scope

In the last 25 years minimally invasive surgery has become commonplace for the relatively easy-to-reach areas of the body, such as keyhole surgery on the abdomen and womb. And more recently surgeons have been able to use scopes (tube-like instruments) in brain surgery too.


Case study

Photo of Elizabeth Watson
  • 71-year-old Elizabeth Watson is one of the first patients in the UK to have had an operation using this system (2013)
  • She had a benign tumour growing on her pituitary – a key hormone-producing gland in the brain
  • She says: “The new equipment helped convince me to have the operation. It looks as though it has been really successful”

During these procedures a thin scope is inserted via a surgically-made or naturally-occurring port in the skin. A camera attached to the end of the scope relays images to a screen for the surgeon to see.

And surgical instruments are passed down the scopes to take samples of tissues or remove masses.

Early versions allowed surgeons to look at 2D images in standard definition, evolving over the last decade into more high definition systems.

Surgeons constantly translate these 2D images into 3D as they operate, much as we do when watching 2D television screens.

More recently 3D technology has become available for certain types of operation. But 3D brain surgery has been a much harder feat to achieve.

In neurosurgery the scopes need to be very small in diameter so they can pass through narrow ports such as the nose.

But most 3D scopes rely on two optical channels – each containing a single sensor. Each sensor collects two separate images that are then mixed together to give the appearance of three dimensions as a user looks at the screen – mirroring the way human eyes see.

It has so far proved difficult to make an instrument small enough that is able to produce the high-quality images neurosurgeons need.

‘Insect eye’

But Mr Yaron says his team have cracked this puzzle by thinking laterally. Rather than copying human anatomy, their scope mimics the compound eye of a bee.

The scope contains a miniature sensor with hundreds of thousands of micron-sized elements, each looking in slightly different directions and mapping the surgical field from many different points.

Using software this is translated into images for the left and right eye. Using this single sensor system, Mr Yaron’s company, Visionsense, have produced a scope small enough to operate on the brain.

Shahzada Ahmed from the Queen Elizabeth Hospital in Birmingham who carried out one of the first 3D endoscopic neurosurgical procedures in the UK says: “A bit like going to the movies, Avatar is a great movie in HD but it is an even better one in 3D.

“When I use the scope there is a better appreciation of depth and the pictures feel more real to me.”


3D brain surgery: possible uses

Illustration of endoscopic brain surgery
  • Removal of tumours and masses at the base of the skull and in the nose
  • Removal of pituitary tumours
  • Sinus surgery

It also allows him to see his instruments in 3D, which he feels gives him a better understanding of where they are in relation to key parts of anatomy.

Model brain

A number of studies are now being carried out to see if the 3D approach is better than commonly used 2D high definition systems.

Hani Marcus, a neurosurgeon at the Hamlyn Centre, Imperial College London recently compared the scope to conventional tools, using a model brain and surgeons who are novices to this endoscopic approach.

The study suggests the 3D aspect is beneficial – leading to a faster operation and subjective improvements in depth perception.

But Mr Marcus says it would be a mistake to automatically assume 3D is definitely better than 2D, and thinks further studies are needed.

There are a number of potential problems – surgeons who are already used to seeing 2D may find this approach hard to get used to.

And just as some people don’t enjoy watching 3D films and feel slightly nauseous, the same may hold for some surgeons.

But for Mr Yaron, whose scope is now being used in the US and across Europe, this invention is the bright side of an issue that has been playing on his mind for many years.

He says: “If I hadn’t had this accident I wouldn’t have been able to offer this solution. And I really know how it feels to need options.”

via BBC News – Head space: Finding a way to do 3D surgery on the brain.

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Miniature ‘human brain’ grown in lab

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Cross-section of miniature human brains termed cerebral organoids

Miniature “human brains” have been grown in a lab in a feat scientists hope will transform the understanding of neurological disorders.

The pea-sized structures reached the same level of development as in a nine-week-old foetus, but are incapable of thought.

The study, published in the journal Nature, has already been used to gain insight into rare diseases.

Neuroscientists have described the findings as astounding and fascinating.

The human brain is one of the most complicated structures in the universe.

Scientists at Institute of Molecular Biotechnology of the Austrian Academy of Sciences have now reproduced some of the earliest stages of the organ’s development in the laboratory.

Brain bath

They used either embryonic stem cells or adult skin cells to produce the part of an embryo that develops into the brain and spinal cord – the neuroectoderm.

This was placed in tiny droplets of gel to give a scaffold for the tissue to grow and was placed into a spinning bioreactor, a nutrient bath that supplies nutrients and oxygen.

Brain
A cerebral organoid – the brown pigments are a developing retina

 

The cells were able to grow and organise themselves into separate regions of the brain, such as the cerebral cortex, the retina, and, rarely, an early hippocampus, which would be heavily involved in memory in a fully developed adult brain.

The researchers are confident that this closely, but far from perfectly, matches brain development in a foetus until the nine week stage.

The tissues reached their maximum size, about 4mm (0.1in), after two months.

The “mini-brains” have survived for nearly a year, but did not grow any larger. There is no blood supply, just brain tissue, so nutrients and oxygen cannot penetrate into the middle of the brain-like structure.

One of the researchers, Dr Juergen Knoblich, said: “What our organoids are good for is to model development of the brain and to study anything that causes a defect in development.

“Ultimately we would like to move towards more common disorders like schizophrenia or autism. They typically manifest themselves only in adults, but it has been shown that the underlying defects occur during the development of the brain.”

The technique could also be used to replace mice and rats in drug research as new treatments could be tested on actual brain tissue.


I think it’s just mindboggling”

Prof Paul MatthewsImperial College London

‘Mindboggling’

Researchers have been able to produce brain cells in the laboratory before, but this is the closest any group has come to building a human brain.

The breakthrough has excited the field.

Prof Paul Matthews, from Imperial College London, told the BBC: “I think it’s just mindboggling. The idea that we can take a cell from a skin and turn it into, even though it’s only the size of a pea, is starting to look like a brain and starting to show some of the behaviours of a tiny brain, I think is just extraordinary.

“Now it’s not thinking, it’s not communicating between the areas in the way our brains do, but it gives us a real start and this is going to be the kind of tool that helps us understand many of the major developmental brain disorders.”

The team has already used the breakthrough to investigate a disease called microcephaly. People with the disease develop much smaller brains.

Brain with microcephaly
A much smaller brain develops with microcephaly

By creating a “mini-brain” from skin cells of a patient with this condition, the team were able to study how development changed.


It’s a long way from conscience or awareness or responding to the outside world. There’s always the spectre of what the future might hold, but this is primitive territory”

Dr Zameel CaderJohn Radcliffe Hospital

They showed that the cells were too keen to become neurons by specialising too early. It meant the cells in the early brain did not bulk up to a high enough number before specialising, which affected the final size of even the pea-sized “mini-brains”.

The team in Vienna do not believe there are any ethical issues at this stage, but Dr Knoblich said he did not want to see much larger brains being developed as that would be “undesirable”.

Dr Zameel Cader, a consultant neurologist at the John Radcliffe Hospital in Oxford, said he did not see ethical issues arising from the research so far.

He told the BBC: “It’s a long way from conscience or awareness or responding to the outside world. There’s always the spectre of what the future might hold, but this is primitive territory.”

The “mini brain” is roughly the size and developmental level of a nine-week foetus

Dr Martin Coath, from the cognition institute at Plymouth University, said: “Any technique that gives us ‘something like a brain’ that we can modify, work on, and watch as it develops, just has to be exciting.

“If the authors are right – that their ‘brain in a bottle’ develops in ways that mimic human brain development – then the potential for studying developmental diseases is clear. But the applicability to other types of disease is not so clear – but it has potential.

“Testing drugs is, also, much more problematic. Most drugs that affect the brain act on things like mood, perception, control of your body, pain, and a whole bunch of other things. This brain-like-tissue has no trouble with any of these things yet.”

via BBC News – Miniature ‘human brain’ grown in lab.

Exercise for the brain

Recent studies reported that an increase in the time dedicated to physical health-based activities is not associated with a decline in academic performance.
Recent studies reported that an increase in the time dedicated to physical health-based activities is not associated with a decline in academic performance.

The therapeutic properties of exercise is well supported by a substantial amount of research.

THE benefits of exercise are well publicised. Exercise is associated with a reduction in physical illnesses such as cardiovascular disease, colon and breast cancer, obesity and mental illness (including depression and anxiety disorders) across the adult lifespan.

The National Health and Morbidity Survey 2011 revealed that about 64.3% of Malaysians were physically active. The level of physical activity gradually decreased with increasing age, and this was particularly apparent in senior citizens.

Despite evidence of the importance of exercise, the prevalence of overweight and obese Malaysians was 29.4% and 15.1% respectively based on the World Health Organization (1998) classification.

Although some are aware of the benefits of exercise, there are many who are unaware that exercise has considerable benefits for the brain. This is put aptly by John Ratey, author of A User’s Guide to the Brain. “Exercise is really for the brain, not the body. It affects mood, vitality, alertness and feelings of well-being.”

There is increasing evidence that exercise can improve learning and memory, delay age-related cognitive decline, reduce risk of neurodegeneration and alleviate depression.

Exercise and brain function

Exercise improves brain function in different ways. It enhances learning and plasticity, is neuroprotective, and is therapeutic and protective against depression

Exercise enhances learning and plasticity, which is the capacity of the brain and nervous system to continuously alter neural pathways and synapses in response to experience or injury.

Although some are aware of the benefits of exercise, there are many who are unaware that exercise has considerable benefits for the brain.
Although some are aware of the benefits of exercise, there are many who are unaware that exercise has considerable benefits for the brain.

The effects of exercise have been demonstrated in ageing human populations in which sustained exercise has augmented learning and memory, improved executive functions, impeded age-related and disease-related mental decline, and protected against age-related atrophy in parts of the brain areas that are vital for higher cognitive processes.

Physical activity has a positive effect on cognition, which includes every mental process that may be described as an experience of knowing (including perceiving, recognising, conceiving, and reasoning).

There is a significant relationship between physical activity and improved cognition in normal adults as well as those with early signs of Alzheimer’s disease (AD), in which there is mild impairment of memory or cognition.

There is a dose-response relationship between exercise and health-related quality of life, with moderate exercise associated with the best outcomes.

The literature on the effects of exercise on cognition during children’s development is less substantial. However, a meta-analysis by Sibley & Etnier reported a positive correlation between physical activity and cognitive performance in children aged between four and 18 years in eight categories, i.e. perceptual skills, intelligence quotient, achievement, verbal tests, mathematic tests, memory, developmental level/academic readiness and others.

A beneficial relationship was found for all categories, with the exception of memory, which was unrelated to physical activity behaviour, and for all age groups, although it was stronger for children in the ages of four to seven and 11 to 13 years, compared with the ages of eight to 10 and 14 to 18 years.

Recent studies have reported that an increase in the time dedicated to physical health-based activities is not associated with a decline in academic performance.

The literature on the impact of exercise on cognition in young adults is limited, probably because cognition peaks during young adulthood and there is little room for exercise-related improvement at this stage of the lifespan.

Although there is considerable evidence that exercise can facilitate learning in humans and other animals, there are gaps in knowledge regarding the types of learning that are improved with exercise.

Therapeutic exercise programmes after a stroke accelerates functional rehabilitation.
Therapeutic exercise programmes after a stroke accelerates functional rehabilitation.

Exercise protects the brain (neuroprotective). It reduces the impact of brain injury and delays the onset and decline in several neurodegenerative diseases. For example, therapeutic exercise programmes after a stroke accelerates functional rehabilitation.

Furthermore, physical activity delays the onset and reduces the risk for AD, Huntington’s disease and Parkinson’s disease, and can even slow functional decline after neurodegeneration has begun.

There is evidence that exercise is therapeutic and protective in depression, which is associated with a decline in cognition.

Depression is considered to be a health burden that is greater than that of ischaemic heart disease, cerebrovascular disease or tuberculosis.

Clinical trials have reported the efficacy of aerobic or resistance training exercise in the treatment of depression in young and older patients, with benefits similar to that of antidepressant medicines. More exercise leads to greater improvements.

Trials have also reported improvement in depressive symptoms in AD compared to those non-exercising individuals whose depressive symptoms worsened.

Bipolar disorders do not appear to respond as well to exercise, but those with anxiety respond even faster.

There is a convergence of the concept that brain health and cognition are influenced by the interplay of various central and peripheral factors. Brain function is believed to be impaired by peripheral risk factors that lead to cognitive decline, including hypertension, hyperglycemia, insulin insensitivity and dyslipidemia, features that are commonly known as the “metabolic syndrome”.

Of these factors, hypertension and glucose intolerance play crucial roles. Exercise not only reduces all these peripheral risk factors but also improves cardiovascular health, lipid–cholesterol balance, energy metabolism, glucose use, insulin sensitivity and inflammation.

As such, exercise improves brain health and function by directly enhancing brain health and cognitive function, and indirectly, by reducing the peripheral risk factors for cognitive decline.

It is believed that exercise initiates an interactive cascade of growth factor signals which lead to the stimulation of plasticity, improvement of cognitive function, reduction of the mechanisms that drive depression, stimulation of neurogenesis and improvement of cerebrovascular perfusion.

Although much is known about the effects of exercise and physical activity on brain and cognition, there are many important questions that are unanswered.

They include questions like the design of exercise interventions which optimise the effects on cognition and brain health; when it is best to begin; what are the best varieties, intensities, frequencies and duration of exercise; is it ever too late to start an exercise programme; and can exercise be used to reduce the effects of neurodegenerative diseases.

Knowing the how

Exercise affects many sites in the nervous system and stimulates the secretion of chemicals like serotonin and dopamine, which make humans feel calm, happy, and euphoric. You do not have to wait for these feelings to occur – you can initiate them by exercising.

There is no shortage of advice on the various physical exercises that enhances cardiovascular health. Prior to embarking on exercise, a consultation with the doctor would be helpful, especially for senior citizens. This will help in choosing the appropriate exercise for one’s individual situation.

In general, what is good for the heart is also good for the brain.

The usual recommended minimum is half an hour of moderate exercise thrice a week. This can be walking, jogging, swimming, playing games, dancing etc.

The public is often reminded about a healthy lifestyle, which is focused on physical health. However, it is also important to exercise mentally and keep the brain healthy.

There are publications and activities available that can help you make a start and continue to improve cognition, memory, creativity and other brain functions.

Anyone at any age can do so, even senior citizens. It is moot to remember the adage: if you don’t use it, you lose it.

The Star

http://thestar.com.my/columnists/story.asp?col=thedoctorsays&file=/2013/6/2/columnists/thedoctorsays/13164220&sec=The%20Doctor%20Says

 

Feed the brain

FRUIT AND VEGETABLES

Eating the right food can help a child’s learning ability. Sushma Veera finds out more

IT is important to give your children the right nutrients to keep them alert and focused at school. Associate professor Dr Loh Su Peng from Universiti Putra Malaysia’s Department Of Nutrition & Dietetics (Faculty Of Medicine And Health Sciences) says a child’s learning ability and behaviour depends on what nutrients the brain can use as fuel.

For brain to stay mentally sharp, children need a constant supply of energy. Here are some effective foods that can give brain power a boost.

FATTY ACIDS

Essential fatty acids (alpha linolenic, EPA and DHA) from fats are used to create specialised cells that allow us to think and feel.
Food: Nuts and seed.

PROTEIN

Amino acids from proteins are used to make neurotransmitters that allow brain cells to network and communicate. Neurotransmitters are brain chemicals that motivate or sedate, focus or frustrate.
Food: Milk, beans and legumes, fish and seafood, eggs, protein.

FRUIT AND VEGETABLES

Micronutrients from food (especially vegetables and fruit) are the antioxidants the brain relies on to safeguard its cells from damage and dysfunction. These protect the brain from normal wear and tear.
Food: Fruit and dark green vegetables.

CARBOHYDRATE

Glucose from carbohydrate is the main fuel the brain uses to produce energy for its function. Sweets and candy do not make the grade because they are simple carbohydrates which, when broken down by the body into glucose, is absorbed very quickly, causing high peaks and sudden drops in glucose levels.

The fibre in complex carbohydrate, on the other hand, slows the body’s absorption of energy, ensuring that the brain gets a slow and steady supply of fuel.
Food: Whole grains (brown rice, oats, breads, pasta, crackers, cereals).

WATER

Proper hydration is critical for concentration and alertness.

Read more:Feed the brain – Health – New Straits Timeshttp://www.nst.com.my/life-times/health/feed-the-brain-1.209141#ixzz2JQT2qTmR

Scientists shift on brain speech center

WASHINGTON (AFP) —

 

The part of the brain used for speech processing is in a different location than originally believed, according to a US study Monday that researchers said will require a rewrite of medical texts.

 

Wernicke’s area, named after the German neurologist who proposed it in the late 1800s, was long believed to be at the back of the brain’s cerebral cortex, behind the auditory cortex which receives sounds.

 

But a review by scientists at Georgetown University Medical Center of more than 100 imaging studies has shown it is actually three centimeters closer to the front of the brain, and is in front of the auditory cortex, not behind.

 

“Textbooks will now have to be rewritten,” said neuroscience professor Josef Rauschecker, lead author of the study which appears in the Proceedings of the National Academy of Sciences.

 

“We gave old theories that have long hung a knockout punch.”

 

Rauschecker and colleagues based their research on 115 previous peer-reviewed studies that investigated speech perception and used brain imaging scans—either MRI (functional magnetic resonance imaging) or PET (positron emission tomography).

 

An analysis of the brain imaging coordinates in those studies pointed to the new location for Wernicke’s area, offering new insight for patients suffering from brain damage or stroke.

 

“If a patient can’t speak, or understand speech, we now have a good clue as to where damage has occurred,” said Rauschecker.

 

It also adds an intriguing wrinkle to the origins of language in humans and primates, who have also been shown to process audible speech in the same region of the brain.

 

“This finding suggests the architecture and processing between the two species is more similar than many people thought.”

 

Lead author Iain DeWitt, a PhD candidate in Georgetown’s Interdisciplinary Program in Neuroscience, said the study confirms what others have found since brain imaging began in earnest in the 1990s, though some debate has persisted.

 

“The majority of imagers, however, were reluctant to overturn a century of prior understanding on account of what was then a relatively new methodology,” he said.

 

“The point of our paper is to force a reconciliation between the data and theory.”

 

Read More: Japan Today

Brain attacks

When blood supply to the brain is compromised, it can lead to damage, and possibly death, of the brain cells, a condition called stroke.

THE human brain has been compared to a supercomputer. But the brain is much more complicated than that, a fact that is confirmed with each new discovery about its capabilities, which is still largely unknown.

This single organ controls all the body’s functions, which include heartbeat, breathing, sexual function, thinking, speech, memory, emotions, movement, and sleep. It influences the immune system’s response to ill health, and determines, to some extent, how a person responds to medical treatment.

In short, the brain makes us human and separates us from other living creatures on planet Earth.

The brain, which is encased in the bony skull, is divided into two sides (hemispheres), each controlling the opposite side of the body.

Different parts of the brain have different functions. The frontal lobe is responsible for the highest intellectual functions like thinking and problem-solving. The parietal lobe is responsible for sensory and motor function. The hippocampus is involved in memory. The thalamus is the relay station for almost all of the information coming into the brain, and the hypothalamus, the relay stations for the systems regulating the body’s functions.

The midbrain has cells that relay specific sensory information from the sense organs to the brain. The hindbrain comprises the pons and medulla oblongata, which control breathing and heart functions, and the cerebellum, which controls movement and cognitive processes that require precise timing.

The brain’s functions depend on a constant blood supply for the oxygen and nutrients needed by its cells. The restriction or stoppage of this supply leads to damage, and possibly death, of the brain cells. This is called a stroke.

A stroke, also called a cerebrovascular accident (CVA), is a condition whereby the blood supply to a part of the brain is cut off. It is a medical emergency, and the earlier treatment is provided, the less severe it will be.

Strokes are the third most common cause of death in Malaysia. It is estimated that there are about 52,000 strokes per annum, i.e. strokes occur in six persons every hour.

Different types

There are two main types of strokes.

Ischaemic strokes, which comprise the majority of stroke cases, occur when the blood supply to the brain stops because the vessel is blocked by a blood clot. This may be due to thrombosis, in which a blood clot forms in one of the brain’s arteries, or to an embolism, in which a blood clot formed elsewhere in the body gets into the brain’s arteries to reach a blood vessel small enough to block its passage.

Haemorrhagic strokes occur when bleeding results from a burst blood vessel supplying the brain because of weakness in its wall. The blood collection compresses the brain, causing damage and loss of function.

A related condition is transient ischaemic attack (TIA) in which there is temporary interruption of the blood supply to part of the brain, leading to a “mini-stroke”. As TIAs provide a warning that a stroke is on the way, they should be treated seriously.

Causes of stroke

Strokes are preventable as lifestyle changes can reduce many of the risk factors. However, there are some risk factors that are not preventable. They include:

·Age – The risks are increased in the older person, although about a quarter of strokes occur in the young.

·Ethnicity – The risks are increased in Indians and Malays because the incidence of diabetes and hypertension are higher in these groups.

·Medical history – The risks are increased if one has had a heart attack, stroke, or TIA.

·Family history – The risks are increased if a close relative has had a stroke.

Ischaemic strokes occur when the brain’s blood supply is blocked by clots formed where the arteries are narrowed or blocked by cholesterol deposits due to atherosclerosis.

Everyone’s arteries get narrower with age, but the process is hastened by factors like high blood pressure, poorly controlled diabetes, raised blood cholesterol, smoking, excessive alcohol intake, obesity and a family history of diabetes or heart disease.

An irregular heartbeat leads to blood clots being thrown off to block the brain’s blood supply. The causes of irregular heartbeats include high blood pressure, coronary artery disease, disease of the heart’s mitral valve, overactive thyroid gland and excessive alcohol intake.

Haemorrhagic strokes occur when a blood vessel of the brain bursts, resulting in bleeding into the brain itself (intracerebral haemorrhage). Sometimes, the bleeding is on the brain surface (subarachnoid haemorrhage).

The primary cause of haemorrhagic stroke is high blood pressure, the risk factors of which include smoking, overweight or obesity, lack of exercise, excessive alcohol intake and stress.

Blood-thinning medicines can also cause haemorrhagic strokes, which can also occur from blood vessel malformations in the brain or an aneurysm, which is a balloon-like swelling of a blood vessel.

Trauma can also cause bleeding in the brain. Although the cause is usually apparent, bleeding into the brain’s lining (subdural haematoma) may occur without signs of trauma.

A rare cause of stroke is blood clot formation in the brain’s veins, which is usually due to clotting abnormalities.

Signs and symptoms

The features vary depending on the part of the brain that is affected and the extent to which it is affected. Strokes usually occur suddenly.

The common features are:

·Face – There may be an inability to smile, open the mouth or the face or eye may hang downwards.

·Arms – There may be an inability to lift one or both arms due to numbness or weakness.

·Legs – There may be an inability to move one or both legs due to numbness or weakness.

·Speech – There may be slurring of speech or an inability to talk at all.

Other features may include sudden vision loss, dizziness, difficulty talking and understanding what others say, difficulty swallowing, balancing problems, sudden and severe headache, and blacking out.

Awareness of the above features is crucial, particularly for those at increased risk of a stroke, and their caregivers.

The complications of stroke include swallowing problems (dysphagia), which affect about a third of stroke patients. This leads to small food particles entering the respiratory tract causing lung infection (pneumonia).

Stroke can also lead to excess cerebrospinal fluid (CSF) in the brain’s ventricles (hydrocephalus) in about 10% of haemorrhagic strokes. CSF, which is produced by the brain, is continuously drained away and absorbed by the body. When its drainage is stopped following a haemorrhagic stroke, the excess CSF causes headaches, loss of balance, nausea and vomiting.

A small percentage of stroke victims who have lost some or all movement in their legs will have blood clot formation in their legs. The features of this deep vein thrombosis (DVT) include swelling, pain, tenderness, warmth and redness, especially in the calf. Urgent diagnosis and treatment is necessary to avoid the clot moving to the lungs, causing pulmonary embolism, which is potentially fatal.

Diagnosing stroke

The diagnosis of a stroke is made by history taking and physical examination. However, imaging of the brain is essential to determine if it is an ischaemic or haemorrhagic stroke, the part of the brain that is affected, and the severity of the stroke.

As the treatments of the different types of stroke vary, a speedy diagnosis will facilitate its management.

The common methods of brain imaging are computerised tomography (CT) scans and magnetic resonance imaging (MRI).

The CT scan involves multiple x-ray imaging to produce detailed three-dimensional images of the brain. MRI involves the use of magnetic and radio waves to produce detailed images of the brain.

Both the CT scan and MRI are used to take images of the brain’s blood vessels, as well as the blood vessels in the neck that connect the heart and the brain’s blood vessels. This procedure, called a CT or MR angiogram. involves injecting a dye into a vein in the arm.

The brain imaging modality used depends on the availability of a CT scan and/or MRI. A CT scan provides enough information if the suspected stroke is major. The MRI is useful if there are complex symptoms, the extent or location of the affected area is unknown, and in patients who have recovered from a TIA.

Brain imaging should be done early; in some patients, within an hour of admission.

A swallow test is usually done for all stroke patients because of the risk of aspiration pneumonia due to dysphagia. This involves giving a few teaspoons of water to the patient and if there is no choking or coughing, to be followed by half a glass of water.

Other investigations of the cardiovascular system will be carried out to determine the cause of the stroke.

It includes ultrasound examination of the heart (echocardiogram) or carotid artery in the neck (Doppler scan). It can also include injecting dye into the carotid or vertebral arteries (arteriography) to enable a detailed examination of the arteries in the brain.

The management of stroke will be discussed in a subsequent article.

Dr Milton Lum is a member of the board of Medical Defence Malaysia. This article is not intended to replace, dictate or define evaluation by a qualified doctor. The views expressed do not represent that of any organisation the writer is associated with. The information provided is for educational and communication purposes only and it should not be construed as personal medical advice. The Star does not give any warranty on accuracy, completeness, functionality, usefulness or other assurances as to the content appearing in this column. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.

The Star

Web addicts have brain changes, research suggests

By Helen Briggs Health editor, BBC News website

Experts in China scanned the brains of 17 young web addicts and found disruption in the way their brains were wired up.

They say the discovery, published in Plos One, could lead to new treatments for addictive behaviour.

Internet addiction is a clinical disorder marked by out-of-control internet use.

A research team led by Hao Lei of the Chinese Academy of Sciences in Wuhan carried out brain scans of 35 men and women aged between 14 and 21.

Seventeen of them were classed as having internet addiction disorder (IAD) on the basis of answering yes to questions such as, “Have you repeatedly made unsuccessful efforts to control, cut back or stop Internet use?”

Specialised MRI brain scans showed changes in the white matter of the brain – the part that contains nerve fibres – in those classed as being web addicts, compared with non-addicts.

There was evidence of disruption to connections in nerve fibres linking brain areas involved in emotions, decision making, and self-control.

Dr Hao Lei and colleagues write in Plos One: “Overall, our findings indicate that IAD has abnormal white matter integrity in brain regions involving emotional generation and processing, executive attention, decision making and cognitive control.

“The results also suggest that IAD may share psychological and neural mechanisms with other types of substance addiction and impulse control disorders.”

Prof Gunter Schumann, chair in biological psychiatry at the Institute of Psychiatry at King’s College, London, said similar findings have been found in video game addicts.

He told the BBC: “For the first time two studies show changes in the neuronal connections between brain areas as well as changes in brain function in people who are frequently using the internet or video games.”

Commenting on the Chinese study, Dr Henrietta Bowden-Jones, consultant psychiatrist and honorary senior lecturer at Imperial College London, said the research was “groundbreaking”.

She added: “We are finally being told what clinicians suspected for some time now, that white matter abnormalities in the orbito-frontal cortex and other truly significant brain areas are present not only in addictions where substances are involved but also in behavioural ones such as internet addiction.”

She said further studies with larger numbers of subjects were needed to confirm the findings.

BBC

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