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Neuro lecture 2/8/07


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  • 1. Standard disclaimer: This is not intended to be a substitute for your own notes. These are the notes I have taken in lecture for my own learning. As such, the content is NOT an exact copy of the powerpoint presentation or the entirety of the lecture. On my distracted days, the notes may even be pretty shoddy. That said, I have tried to provide links to reputable websites where you can find more information. As always, refer to your textbooks and your instructors for the final word. I’ll try to sort things out a little more and organize the information, but the lecture was so disjointed I had to give up. Sorry. If you have any specific things you’d like me to look up for you, let me know. Seizure Thursday, February 08, 2007 8:31 AM Client assessment and care Precipitating factors Fever Menstruation- estrogen increases Emotional stress Metabolic disturbance/electrolyte Drugs Heat Non-compliance to meds Constipation Sleep deprivation Alcohol Withdrawal Toxins Strobe lights Cigarettes (nicotine) Assessment focus Based on history Tracking Epilepsy patients can sometimes predict seizures
  • 2. nursing care Thursday, February 08, 2007 8:53 AM Examples of neurological disorders that cause mental-emotional changes Alzheimers Parkinsons Multiple sclerosis Epilepsy Cerebral palsy (similar to CVA) Depends on where the lesion is Assessment Appearance, behavior Speech, vocabulary, language Mood, lability Right vs Left brain Orientation, memory Attention, concentration General knowledge, education Abstract vs concrete reasoning Judgement, planning, insight Parietal lobe does judgement Follow commands Ability to learn and retain
  • 3. Object identification Physical assessment Inspection Palpation Cranial nerves Thursday, February 08, 2007 9:05 AM Huntington's's_disease ALS CFID=3439646&CFTOKEN=12512690 Guillain-Barre syndrome Affects all cranial nerves except 1, 2, 8 Tutorials ALS osis/htm/index.htm Bell's palsy m Multiple sclerosis dex.htm Myasthenia gravis ndex.htm Parkinson's index.htm Seizures and epilepsy m/index.htm Cranial nerves Thursday, February 08, 2007 9:11 AM
  • 4. Cranial nerve quiz On Old Olympus Towering Top A Famous Vocal German Viewed Some Hops. (olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, spinal accessory, hypoglossal.) Tutorial and video of cranial nerve neuro exam Hemianopsia, blindness Acuity EOM Diplopia Nystagmus Face/head position Jaw movement, chewing, speaking Sensation Drooping, drooling Eyelids Hearing, tinnitus Gag Swallowing, tongue
  • 5. Motor and cerebellar dysfunction Thursday, February 08, 2007 9:48 AM Assessment Flaccidity Spacticity Weakness, fatigueability Paralysis Tremors Description of different types of tremors Coordination Gait
  • 6. Neglect Diaphragm Innervated by C3,4,5 Also affected by Guillain-Barre syndrome Check how many words they can say at a time Have them sniff Specific diseases Thursday, February 08, 2007 9:41 AM Myasthenia gravis Introduction Myasthenia gravis is a chronic disorder characterized by weakness and rapid fatigue of any of the muscles under your voluntary control. The cause of myasthenia gravis is a breakdown in the normal communication between nerves and muscles. The disorder affects only the function of your muscles, and the muscle weakness you experience improves when you rest. Myasthenia gravis may cause double vision, drooping eyelids, difficulties with speech, chewing, swallowing and breathing, as well as weakness of your limbs. Myasthenia gravis can affect people of any age, but it's more common in women younger than 40 or older than 70, and in men older than 50. There's no cure for myasthenia gravis, but treatments are available to help control the signs and symptoms of the condition. Signs and symptoms Myasthenia gravis can affect any of the muscles that you control voluntarily. It most commonly affects certain muscles, including those of your face, eyes, arms and legs, and those muscles involved in chewing, swallowing and talking. Muscles that control breathing and the movement of your head, arms and legs also can be involved. Signs and symptoms may include: • Facial muscle weakness, including drooping eyelids • Double vision • Difficulty in breathing, talking, chewing or swallowing • Muscle weakness in your arms or legs • Fatigue brought on by repetitive motions The more often a muscle action is repeated, the worse the weakness becomes. In myasthenia gravis, good days may alternate with bad days. Temporary remissions may occur. In rare cases, breathing or swallowing problems worsen markedly, requiring emergency medical care. Causes CLICK TO ENLARGE
  • 7. Thymus gland and lymphatic system When your neuromuscular system functions normally, the chemical acetylcholine transmits nerve impulses to your muscles. At specialized areas of your muscles, called neuromuscular junctions, receptor sites receive nerve impulses and signal your muscles to contract, such as when you raise a spoon to your mouth. In myasthenia gravis, there's a breakdown in communication between your nerves and your muscles. The culprit is your immune system. For unknown reasons, myasthenia gravis causes your immune system to produce antibodies that block or destroy many of the receptor sites for acetylcholine in your muscles. With fewer receptor sites available, your muscles receive fewer nerve signals, resulting in weakness. It's believed that the thymus gland, a part of your immune system located in the upper chest beneath the breastbone, may trigger or maintain the production of these antibodies. Large in infancy, the thymus is small in healthy adults. But, in some adults with myasthenia gravis, the thymus is abnormally large. Some people also have tumors of the thymus. Usually, thymus gland tumors are noncancerous (benign). Some factors can make myasthenia gravis worse, including fatigue, illness, stress, extreme heat, and some medications, such as beta blockers, calcium channel blockers, quinine and some antibiotics. Check with your doctor before taking any new medications, even over-the-counter drugs. When to seek medical advice If you experience muscle weakness or have difficulty controlling the muscles of your eyes, face and mouth, have trouble breathing or experience fluctuating weakness in your arms and legs, see your doctor. These signs and symptoms could be indications of myasthenia gravis. Although there's no cure for myasthenia gravis, the outlook for managing its signs and symptoms is good. The earlier you see your doctor, the sooner treatments can be initiated to help you improve your muscle strength, and the sooner you can learn about strategies to help you use your energy in the most efficient ways. Screening and diagnosis The key sign that points to the possibility of myasthenia gravis is muscle weakness that improves with rest. Tests to confirm the diagnosis may include: • Neurological examination. This may include testing of your reflexes, muscle strength, muscle tone, senses of touch and sight, gait, posture, coordination, balance and mental skills. • Blood analysis. A blood test may reveal the presence of abnormal antibodies that disrupt the receptor sites where nerve impulses signal your muscles to move. • Edrophonium test. Injection of the chemical edrophonium (Tensilon) may result in a sudden, although temporary, improvement in your muscle strength, an indication that you may have myasthenia gravis. Edrophonium acts to block an enzyme that breaks down acetylcholine, the chemical that transmits signals from your nerve endings to your muscle receptor sites. • Nerve conduction studies and single-fiber electromyography. During the first part of this test, a small electrical impulse is applied to your skin, stimulating your nerves in order to test the strength of your muscle contraction. In the second part, a thin-needle electrode inserted into one of your muscles helps measure patterns of electrical activity in your muscle at rest and with slight muscle contraction.
  • 8. Treatment Doctors use a variety of treatments, alone or in combination, to relieve symptoms of myasthenia gravis: • Medications. Drugs called cholinesterase inhibitors, such as pyridostigmine (Mestinon) and neostigmine (Prostigmin), enhance communication between nerves and muscles. These drugs don't treat the underlying problem, but they do improve muscle contraction and muscle strength. Corticosteroids inhibit the immune system, limiting antibody production. Prolonged use of corticosteroids, however, can lead to serious side effects, such as bone thinning, weight gain, diabetes, increased risk of some infections and a redistribution of body fat. Your doctor may also prescribe other medications that alter your immune system, such as azathioprine (Imuran), mycophenolate mofetil (CellCept), cyclophosphamide (Cytoxan) or cyclosporine (Sandimmune, Neoral). • Surgery. It's generally been believed that removal of the thymus gland (thymectomy) brings relief to the majority of people with myasthenia gravis. But only about 25 percent of those who have the surgery go into remission within a year, and significant improvement is often delayed for years. The surgery has generally been recommended for people younger than 60. Recent analysis has cast some doubt on the benefit of thymectomy in people who have myasthenia gravis but do not have thymomas (tumors in the thymus). A large international trial is being conducted to assess whether thymectomy should be routinely recommended in that group. • Plasmapheresis (plaz-muh-fuh-RE-sis). This procedure can remedy life-threatening stages of myasthenia gravis. Plasmapheresis involves removal of antibodies from your blood that block transmission of signals from your nerve endings to your muscles' receptor sites. Blood is taken from your body, passed through a filter that removes antibodies and then returned to your body. This approach is expensive and time-consuming. Also, other forms of therapy are necessary for long-term restoration of muscle strength. Otherwise, the immune system soon makes new antibodies to replace those that have been removed. • Intravenous immune globulin. This therapy provides your body with normal antibodies, which alters your immune system response. It has a lower risk of side effects than do plasmapheresis and immune- suppressing therapy, but it can take a week or two to start working and lasts only several weeks to months. This therapy is expensive, and it's not clear that intravenous immune globulin offers clear advantages over other available therapies. For those reasons, it's often reserved for people who are severely ill. As part of your treatment, your doctor may suggest physical therapy and occupational therapy to help you adjust to tasks you need to do around the house and in your job. Be sure not to take any medications without checking with your doctor. Some medications, such as some heart medications and botulinum toxin, can worsen myasthenia gravis.
  • 9. Coping skills Supplementing your medical care with these approaches may help you make the most of your energy and cope with the symptoms of myasthenia gravis: • Adjust your eating routine. Try to eat when you have good muscle strength. A good time is after taking a cholinesterase inhibitor, such as pyridostigmine (Mestinon) and neostigmine (Prostigmin). Also, take your time eating and rest between bites. More frequent, smaller meals may be easier to handle. Also, try soft foods and avoid sticky foods that require lots of chewing. • Use safety precautions at home. Install grab bars or railings in places where you may need support, such as next to the bathtub. Keep the floors and halls in your house clear of clutter, cords and loose rugs. Outside your home, keep the steps, sidewalk and path to your car clear. • Use electric appliances and power tools. Save your energy in the bathroom, in the kitchen or at the workbench by using electric appliances, such as toothbrushes, can openers and screwdrivers. • Wear an eye patch. If you have double vision, using an eye patch can help relieve this problem. Wear the patch while you read or watch television. To avoid eyestrain, periodically switch the patch from one eye to the other. • Plan. If you have a chore to do around the house, shopping to do or an errand to run, plan the activity to coincide with the time at which your medication provides your peak energy level. If you're working on a project at home, gather everything you need for the job at one time, to eliminate extra trips that may drain your energy. • Ask for help. Depending on your energy level, you may not be able to do everything you have planned around the house or run every errand that you need to. Ask family members and friends to lend a hand. • Manage stress. Because emotional stress can make myasthenia gravis worse, look for ways to reduce stress. These may include relaxation techniques such as biofeedback and meditation. By Mayo Clinic Staff Jan 19, 2007 © 1998-2007 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "," "EmbodyHealth," "Reliable tools for healthier lives," "Enhance your life," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research. DS00375 Guillain-Barre syndrome Introduction Guillain-Barre (ge-YAH buh-RA) syndrome (GBS) is an inflammatory disorder in which your body's immune system attacks the nerves outside the brain and spinal cord (peripheral nerves) and, rarely, parts of the brain itself. Severe weakness and
  • 10. numbness in your legs and arms characterize GBS. Loss of feeling and movement (paralysis) may occur in your legs, arms, upper body and face. GBS affects an estimated one to three in every 100,000 persons annually in the United States. It can strike any race at any age, but its incidence increases with age. GBS may occur within days or weeks after a viral infection such as influenza (flu) or diarrhea. It may be triggered by pregnancy or a medical procedure, such as a vaccination or minor surgery, or have no evident reason for developing. Because the cause of GBS is unknown, there's no way to prevent the disease from occurring. In its most severe form, GBS is a medical emergency and may require hospitalization. Severe GBS may result in total paralysis, potentially dangerous fluctuations in heart rate and blood pressure, and inability to breathe without respiratory assistance. The muscles you use for eye movement, speaking, chewing and swallowing also may become weak or paralyzed. People with severe GBS often need long-term rehabilitation to regain normal independence, and as many as 15 percent experience lasting physical impairment. In some cases, GBS can be fatal. Most people recover from even the most severe cases of GBS. Available treatments, if started soon after signs and symptoms appear, may lessen the severity of GBS and reduce recovery time. Signs and symptoms The signs and symptoms of GBS usually appear rapidly over the course of a single day. These may include: • Weakness, tingling or loss of sensation that often begins in your feet and legs and spreads to your upper body and arms • Moderate pain throughout your body • Difficulty breathing • Paralysis of your legs, arms, respiratory muscles and face • Difficulty with eye movement, facial movement, speaking, chewing or swallowing • Very slow heart rate or low blood pressure • Difficulty with bladder control or intestinal functions GBS progresses quickly, with most people experiencing the most significant weakness in the legs, arms, chest and other areas within three weeks of the start of this disorder. In some cases, the signs and symptoms of GBS may progress very rapidly with complete paralysis of legs, arms and breathing muscles over the course of a few hours. If GBS is mild, the signs and symptoms may not extend beyond a feeling of general weakness. GBS may improve on its own within a few weeks, and some people initially may think the signs and symptoms are due simply to a common virus. The signs and symptoms of GBS may last days, weeks or months before muscle sensation begins to return. Regaining your pre-illness strength and functioning is slow, sometimes requiring months or years. However, most people with GBS return to normal within months. Causes CLICK TO ENLARGE Nerve and myelin sheath Doctors and scientists don't know what causes Guillain-Barre syndrome. However, they believe that GBS is a disorder of the immune system. Research indicates that
  • 11. the immune system may destroy the protective covering of the peripheral nerves (myelin sheath), which disables the nerves from transmitting signals to the muscles. When this happens, muscles become unable to respond to nerve commands. Weakness, numbness or paralysis may occur. The brain also receives fewer sensory signals, resulting in the inability to feel heat, cold, pain and other sensations. The most recognized conditions that occur before GBS develops are bacterial or viral infections. Approximately two-thirds of people affected by GBS have had a recent infectious illness, such as sore throat, diarrhea, cold or flu, within one to four weeks before the onset of GBS. The Epstein-Barr virus or Hodgkin's disease also may precede GBS. A bacterial infection such as campylobacteriosis — caused by campylobacter, bacteria commonly found in undercooked food, especially poultry — may be a possible cause of GBS. This form of the disorder is usually more severe because it directly attacks the nerves, instead of the nerve coverings. GBS may also be triggered by medical procedures including surgery and, in rare cases, influenza immunizations. However, the connection between the flu vaccine and GBS is weak, and the risk the vaccine poses to your health is much less significant than your risk of serious flu-related illness. When to seek medical advice GBS is a serious disease that requires immediate hospitalization because of the rapid rate at which it worsens. Early treatment is important. The sooner appropriate treatment is started, the better the chance of a good outcome. If treatment can result in reducing the inflammation of your peripheral nerves, the chances of serious permanent damage to the myelin sheath and nerve fibers may be substantially decreased. If you experience a tingling sensation in your toes, feet or legs followed by muscle weakness, seek medical attention immediately. Failure to see your doctor promptly may lead to progression of the disorder and paralysis, which can leave you incapacitated and unable to get help. Screening and diagnosis GBS can be difficult to diagnose in its earliest stages. Its signs and symptoms are similar to those of other neurological disorders and may vary from person to person. The first step in diagnosing GBS is for your doctor to take a careful medical history to fully understand the cluster of signs and symptoms that you're experiencing. People with GBS have a relatively sudden onset of signs and symptoms, and muscle weakness usually occurs on both sides of the body as opposed to on one side only, as in a stroke. Doctors commonly use two tests to determine if GBS is present: • Electromyography (EMG). An EMG helps establish a diagnosis and the extent of a neurological problem by measuring the electrical activity of a muscle in response to nerve stimulation. The test also measures the nature and speed of impulse conduction along a nerve. In an EMG, a technician inserts electrodes in fine needles into the muscles being tested and places electrodes on your skin over peripheral nerves. • Spinal tap (lumbar puncture). This procedure involves inserting a needle into your spinal canal, usually at the low back (lumbar) level. Your doctor can determine the pressure of the cerebrospinal fluid (CSF), and a sample of fluid can be removed for laboratory analysis. This analysis may include checking for evidence of bleeding, the
  • 12. number and types of white blood cells, the levels of glucose and protein, the types of proteins, and tests for bacteria and fungi. Complications The long-term outlook for most people with GBS is good. About 75 percent to 85 percent of those affected recover completely or have only minor, residual weakness or abnormal sensations such as numbness or tingling. Up to 15 percent of people with GBS experience more serious, permanent problems with sensation and coordination, including some cases of severe disability. About one in ten of those affected is at risk of experiencing a relapse. GBS may cause severe damage to your muscles and nervous system, weakening your heart and lungs. About one-third of people with GBS require assisted ventilation while they are ill. Up to one in 12 people with GBS die of related complications such as respiratory failure, pulmonary embolism and cardiac arrest. Older adults with other medical problems are at greatest risk of death from GBS. Treatment There's no cure for GBS. However, certain therapies can lessen the severity of the illness and accelerate recovery for most people. The general treatment for GBS is supportive care to help with activities of daily living, such as eating and using the bathroom. For some, recovery can take a long time — from several months to a year or more. According to a guideline developed by the American Academy of Neurology (AAN), treating GBS early, within two to four weeks after signs and symptoms first appear, may speed recovery time. Two main treatments, both equally effective, have been shown to speed the recovery from and reduce the severity of GBS in adults: • Plasmapheresis (plaz-muh-fuh-RE-sis). This treatment — also known as plasma exchange — is a type of "blood cleansing" in which damaging antibodies are removed from your blood. Plasmapheresis consists of removing the liquid portion of your blood (plasma) and separating it from the actual blood cells. The blood cells are then put back into your body, which manufactures more plasma to make up for what was removed. It's not clear why this treatment works, but scientists believe that plasmapheresis removes certain antibodies from plasma that contribute to the immune system attack on the peripheral nerves. • Intravenous immunoglobulin (IVIg). Immunoglobulin contains healthy antibodies from blood donors. High doses of immunoglobulin can block the damaging antibodies in your blood that may contribute to GBS. The AAN guideline also shows no benefit in combining plasma exchange and IVIg. Mixing the treatments or administering one after the other is no more effective than if either method is used alone. Your treatment also may include pain medications including acetaminophen and nonsteroidal anti-inflammatory drugs, possibly in combination with narcotic painkillers. Often before recovery begins, caregivers may need to manually move your arms and legs to help keep your muscles flexible and strong. After recovery has begun, you'll likely need physical therapy to help regain strength and proper movement to be able to function on your own. Whirlpool therapy (hydrotherapy) may help relieve pain and retrain the movement of your affected limbs. After your symptoms subside, your rehabilitation team will prescribe an active exercise routine to help you regain muscle
  • 13. strength and independence. You may need training with adaptive devices, such as a wheelchair or braces, to give you mobility and self-care skills. Self-care Depending on the severity of GBS, self-care may be limited until the recovery process has begun. Once the crisis phase is over and rehabilitation starts, work closely with your doctor and rehabilitation team to ensure the best possible outcome. Although it's often difficult and sometimes painful, try to be as cooperative as possible during physical therapy and other demanding rehabilitation activities. Know that your hard work, dedication and perseverance will pay off with the regaining of your mobility and independence. Coping skills Living with a physical disability presents daily challenges. Some of these suggestions may make it easier for you to cope: • Set priorities. Decide which tasks you need to do on a given day and which can wait until another time. Stay active, but don't overdo it. • Get out of the house. When your mobility is restricted, it's natural to want to be alone. But this only makes it easier to focus on your disability. Instead, ask a friend to visit or take you on short errands. • Seek and accept support. It isn't a sign of weakness to ask for or accept help when you need it. In addition to support from family and friends, consider joining a support group. Although support groups aren't for everyone, they can be good places to hear about coping techniques or treatments that have worked for others. You'll also meet people who understand what you're going through. To find a support group in your community, check with your doctor, a nurse or the county health department. • Talk to a counselor or therapist. You may find it helpful to talk to a counselor or therapist in addition to your primary care doctor. Counseling can help relieve the emotional difficulties you're feeling because of your sudden paralysis and dependence on others. By Mayo Clinic Staff May 31, 2005 © 1998-2007 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "," "EmbodyHealth," "Reliable tools for healthier lives," "Enhance your life," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research. DS00413 Amyotrophic lateral sclerosis Introduction Amyotrophic lateral sclerosis (ALS) is a serious neurological disease that attacks the nerve cells that control voluntary muscles. It may begin with muscle twitching or weakness in an arm or leg, or with slurring of speech. Eventually, amyotrophic lateral sclerosis affects your ability to control the muscles needed to move, speak, eat and breathe.
  • 14. In the United States, amyotrophic lateral sclerosis is often called Lou Gehrig's disease, after Hall of Fame baseball player Lou Gehrig of the New York Yankees, who died of the disease in 1941. The cause of amyotrophic lateral sclerosis remains elusive, as does any treatment that can reverse the relentless progression of the disease. Treatment of amyotrophic lateral sclerosis typically focuses on efforts to relieve symptoms and maintain quality of life in the years after diagnosis. Signs and symptoms Signs of amyotrophic lateral sclerosis are typically subtle at first. The disease commonly begins in one part of the body and progresses to other areas. Gradual death of nerve cells saps muscles of their control. Early signs and symptoms of ALS include: • Difficulty lifting the front part of your foot (footdrop) • Weakness in your leg, feet or ankles • Hand weakness or clumsiness • Slurring of speech or trouble swallowing • Muscle cramps and twitching in your arms, shoulders and tongue • Fatigue in combination with the above signs and symptoms The disease frequently begins in your hands, feet or limbs, and then spreads to other parts of your body. It eventually affects chewing, swallowing, speaking and breathing — which are known as bulbar functions after the bulb-shaped part of the brainstem that houses nerve cells controlling these functions. Less commonly, ALS begins with these bulbar symptoms. As the disease advances, your muscles become progressively weaker until they're paralyzed. Eventually, amyotrophic lateral sclerosis paralyzes the muscles needed to breathe. Most people with ALS die of respiratory failure, usually within three to five years after symptoms begin. Sometimes, people with amyotrophic lateral sclerosis develop pneumonia because they can't swallow and they inhale (aspirate) food and oral secretions into their lungs. ALS usually leaves intellect intact and spares the senses of sight, hearing, smell, taste and touch. It doesn't affect involuntary muscles, such as the muscles that control heartbeat and bladder and bowel function. Causes CLICK TO ENLARGE Nerve cells The basic units of your central nervous system — which includes your brain and spinal cord — are nerve cells (neurons). Each neuron consists of a cell body, a major branching fiber (axon) and numerous smaller branching fibers (dendrites). Nerve cells communicate with adjacent nerve cells at contact points called synapses. They also send and receive signals throughout your body. Nerve signals provide information to your brain through your senses. They communicate with your involuntary muscles — the ones that control activities such as digestion, sexual function and heartbeat. Nerve signals also activate your voluntary muscles. Amyotrophic lateral sclerosis is a disease that involves death of motor neurons — the nerve cells that control voluntary muscles. These are the muscles you use to move your limbs, face, neck and torso and to talk, chew, swallow and breathe. In ALS,
  • 15. both upper motor neurons, located in your brain, and lower motor neurons, located in your spinal cord, gradually die. As a result, your voluntary muscles no longer receive messages. These muscles become weak and begin to waste away (atrophy). Researchers aren't sure what causes motor neuron deterioration, but amyotrophic lateral sclerosis appears to fall into two categories: • Inherited (familial) ALS. Up to one in 10 cases of ALS appear to be inherited. About 20 percent of these cases result from a specific gene mutation in an enzyme known as superoxide dismutase 1 (SOD1). Scientists and researchers are still trying to identify other ALS gene mutations that may be inherited. • Sporadic ALS. More than 90 percent of cases of ALS appear to occur randomly, with no identifiable cause and no obvious risk factors. One possible cause of amyotrophic lateral sclerosis is excess glutamate — one of the many chemicals (neurotransmitters) that neurons use to send signals to one another. People with ALS appear to have too much glutamate in their nervous systems, which can cause neurons to die. Researchers are studying other factors that may contribute to amyotrophic lateral sclerosis, including viruses, immune system abnormalities, environmental toxins, cell suicide (apoptosis), defects in the energy-producing parts of a cell (mitochondria) and the buildup of certain proteins known as neurofilaments. Some researchers believe that a combination of more than one factor may trigger ALS. Risk factors Although most cases of amyotrophic lateral sclerosis have no apparent cause, a small percentage of people who have ALS inherit it. Inherited ALS may strike at a younger age and will affect consecutive generations. If you're the first person in your family to have amyotrophic lateral sclerosis, you likely don't have an inherited form, and your children aren't at a greater risk. Noninherited ALS often develops between ages 40 and 60, although the disease affects people of all ages. ALS affects more men than women. When to seek medical advice If you've noticed weakness in one of your limbs or twitching and cramping in your muscles, see your doctor to determine if there may be a neurological cause such as amyotrophic lateral sclerosis. Although there's no treatment to reverse the course of ALS, other neurological conditions that may mimic some of the signs and symptoms of ALS are treatable. It's easy to ignore the early, sometimes subtle signs of amyotrophic lateral sclerosis. In fact, it takes about a year before most people are diagnosed with ALS. But the sooner you see your doctor, the sooner a diagnosis and treatment decisions can be made. Screening and diagnosis Amyotrophic lateral sclerosis is difficult to diagnose early because it may appear similar to other neurological diseases. Your doctor may refer you to a doctor who specializes in brain and nervous system disorders (neurologist). Diagnosing amyotrophic lateral sclerosis first involves reviewing your family's medical history and your signs and symptoms. You'll then have a physical examination that may include some basic in-office testing of your nerves and muscles. Additionally, you'll undergo a variety of tests, including tests to rule out other conditions. These diagnostic tests may include: • Electromyogram (EMG). Electromyography measures the tiny electrical discharges produced in muscles. A thin-needle electrode is
  • 16. inserted into the muscles that your doctor wants to study. An instrument records the electrical activity in your muscle as you rest and contract the muscle. • Nerve conduction study (NCS). As a part of an electromyography study, two electrodes are taped to your skin above a nerve or muscle to be studied. A small shock is passed through the nerve to measure the size and speed of nerve signals. • Imaging. Your doctor may suggest magnetic resonance imaging (MRI) or a computerized tomography (CT) scan to produce images of your brain and spinal cord. These tests can help your doctor determine if something other than ALS may be causing your signs and symptoms. • Spinal tap (lumbar puncture). This test analyzes the fluid surrounding your brain and spinal cord (cerebrospinal fluid). You typically lie on your side with your knees drawn up to your chest. A local anesthetic is injected in an area over your lower spine to reduce any discomfort from the procedure. Then a needle is inserted into your spinal canal, and fluid is collected. Tests on this fluid indicate the number and types of white blood cells, the level of sugar, and the levels and types of proteins. Additional tests on this fluid can indicate evidence of bleeding, infection and abnormal cells. • Blood and urine tests. Analyzing samples of your blood and urine in the laboratory may help your doctor eliminate other possible causes of your signs and symptoms. • Muscle biopsy. If your doctor believes you may have a muscle disease rather than ALS, you may undergo a muscle biopsy. In this procedure, a small portion of tissue is removed while you're under local anesthesia and is sent to a lab for analysis. Treatment Because there's no reversing the course of amyotrophic lateral sclerosis, treatments mainly involve efforts to make you more comfortable and independent and to slow the progression of symptoms. Treatments may involve many professionals, including doctors, therapists, dietitians, social workers and hospice nurses, and may include: • Medications. The drug riluzole (Rilutek) is the first and only medication approved by the Food and Drug Administration for slowing ALS. The drug appears to slow the disease's progression and prolong life by a few months in some people, perhaps by reducing glutamate levels. Your doctor may also prescribe medications to provide relief from muscle cramps and constipation and to reduce fatigue, excessive salivation and excessive phlegm. Some people with amyotrophic lateral sclerosis also benefit from medications for pain or depression. • Physical and occupational therapy. A physical therapist can recommend low-impact exercises to maintain your muscle strength and range of motion as long as possible, helping you preserve a sense of independence. An occupational therapist can help you become accustomed to a brace, walker or wheelchair and may be able to suggest devices such as ramps that make it easier for you to get around. • Speech therapy. Because ALS affects the muscles you use to speak, communicating clearly becomes an issue as the disease progresses. A speech therapist can help teach techniques to make your speech more clearly understood. Later in the disease, a speech therapist can
  • 17. recommend devices such as speech synthesizers and computers that may help you communicate. • Nutritional support. A dietitian can advise you on foods that are nutritious but easy to swallow. As the disease progresses and you have greater difficulty swallowing, you may consider a feeding tube inserted into your stomach to receive nutrition and avoid choking. • Breathing assistance. ALS progressively weakens the muscles you need for breathing, making it more difficult to breathe. At first, you may benefit from a device that makes it easier for you to breathe during the night. Some devices, such as masks or nose inserts, fit over your face and are easy to use or remove. The mask or nose insert is attached to a portable machine that provides air pressure to inflate your lungs. You can also use these devices during the day. As breathing muscles weaken further, you may need to decide whether or not to use the full-time help of a respirator that inflates and deflates your lungs. A respiratory therapist or lung specialist (pulmonologist) can help you choose devices that will work for you. New treatments Researchers are investigating many other medications for their usefulness in treating amyotrophic lateral sclerosis. Examples include the antibiotic minocycline (Minocin), the breast cancer drug tamoxifen, the antioxidant coenzyme Q10 and a nerve- nourishing drug called insulin-like growth factor (IGF-I). Increasingly, researchers are studying drug "cocktails" — which are combinations of medications. Stem cell therapy is another avenue of research. Early studies show that stem cells may have the ability to repair or replace the motor neurons damaged by ALS, but clinical use or clinical trials with stem cell therapy is still a long way off. Only time will tell if these new treatments will be useful. It's important to work closely with a doctor who specializes in amyotrophic lateral sclerosis, who will be informed as new discoveries and treatments may become available. Some health care centers offer ALS clinics where people with ALS can work with physical therapists, occupational therapists, speech therapists, nurses, social workers and other people with ALS — all in the same place. Coping skills No one chooses to live with amyotrophic lateral sclerosis. Yet many have managed to do it with daring, dignity, humor and a hopeful attitude. If you have ALS, you can, too. • Take time to accept your diagnosis and the changes it will bring. Hearing that you have a fatal condition that will rob you of your mobility and independence is often nothing less than shocking. If you are newly diagnosed, you and your family will likely experience a period of mourning and grief that is similar to the period after the death of a loved one. Although the grieving process is different for everyone, it's common to experience denial or disbelief, then sadness, anger, bargaining and, finally, acceptance. • Be hopeful. Some people with amyotrophic lateral sclerosis live much longer than the three to five years typically associated with this condition. Some live 10 years or more. Keeping hope alive is vital for people with ALS. • Think beyond the physical changes. ALS doesn't typically affect the intellect or spirit. Many people with amyotrophic lateral sclerosis lead rich, rewarding lives. Try to think of ALS as only one part of your life, not your entire identity.
  • 18. • Join a support group. Having amyotrophic lateral sclerosis greatly changes your lifestyle and that of your family and may create a high financial burden. You may find comfort in sharing your concerns in a support group with others who have ALS. Your caregivers may also benefit from a support group of others who care for people with amyotrophic lateral sclerosis. Find support groups in your area by talking to your doctor or by contacting the ALS Association. • Make decisions now about your future medical care. Planning for the future allows you to be in control of decisions about your life and your care. With the help of your doctor or hospice nurse, you can decide whether or not you want certain life-extending procedures. And you can determine where you want to spend your final days. Talking about these issues isn't easy. But facing your anxieties about the future may help you better enjoy life today. By Mayo Clinic Staff Dec 1, 2006 © 1998-2007 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "," "EmbodyHealth," "Reliable tools for healthier lives," "Enhance your life," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research. DS00359 Thursday, February 08, 2007 9:50 AM Multiple sclerosis Introduction Multiple sclerosis (MS) is a chronic, potentially debilitating disease that affects your central nervous system, which is made up of your brain and spinal cord. Multiple sclerosis is widely believed to be an autoimmune disease, a condition in which your immune system attacks components of your body as if they're foreign. In multiple sclerosis, the body mistakenly directs antibodies and white blood cells against proteins in the myelin sheath, a fatty substance that insulates nerve fibers in your brain and spinal cord. This results in inflammation and injury to the sheath and ultimately to the nerves that it surrounds. The result may be multiple areas of scarring (sclerosis). Eventually, this damage can slow or block the nerve signals that control muscle coordination, strength, sensation and vision. Multiple sclerosis affects an estimated 300,000 people in the United States and probably more than 1 million people around the world — including twice as many women as men. Most people experience their first signs or symptoms between ages 20 and 40. Multiple sclerosis is unpredictable and varies in severity. In some people, multiple sclerosis is a mild illness, but it can lead to permanent disability in others. Treatments can modify the course of the disease and relieve symptoms.
  • 19. Signs and symptoms Signs and symptoms of multiple sclerosis vary widely, depending on the location of affected nerve fibers. Multiple sclerosis symptoms may include: • Numbness or weakness in one or more limbs, which typically occurs on one side of your body at a time or the bottom half of your body • Partial or complete loss of vision, usually in one eye at a time, often with pain during eye movement • Double vision or blurring of vision • Tingling or pain in parts of your body • Electric-shock sensations that occur with certain head movements • Tremor, lack of coordination or unsteady gait • Fatigue • Dizziness In some cases, people with multiple sclerosis may also develop muscle stiffness or spasticity, slurred speech, paralysis, or problems with bladder, bowel or sexual function. Mental changes, such as forgetfulness or difficulties with concentration, also may occur. Causes CLICK TO ENLARGE Multiple sclerosis Your central nervous system contains millions of nerve cells that send their electrical signals to and from your brain along wire-like extensions of the cells called axons, or nerve fibers. Myelin is the fatty substance that coats and protects these fibers, similar to the way insulation shields electrical wires. In people with multiple sclerosis, the immune system mistakenly destroys the cells that produce the myelin sheath. As a result, myelin becomes inflamed and swollen and detaches from the nerve fibers. The detached myelin may eventually be destroyed. Firm or hardened (sclerosed) patches of scar tissue form over the fibers. When nerve impulses reach a damaged area, some impulses are blocked or delayed from traveling to or from your brain. Ultimately, this process leads to degeneration of the nerves themselves, which likely accounts for the permanent disabilities that may develop in MS. Doctors and researchers don't understand what causes this autoimmune reaction. Something seems to trigger the condition in susceptible people. Genetic factors may make certain people more susceptible to multiple sclerosis. But genetic susceptibility is only part of the explanation. A number of researchers believe the disorder is related to a protein that mimics the myelin protein, which may be introduced into the body by a virus. Other researchers believe that the immune system overreacts toward myelin proteins in people with MS, which leads to an abnormal tendency to develop autoimmune disease. A period of disease activity (exacerbation) may be triggered by a viral infection, such as a cold or flu, or by changes in the immune system during the first six months following a pregnancy. Patterns of MS Whatever the multiple sclerosis cause or trigger, the disease occurs in four main patterns:
  • 20. • Relapsing remitting. This type of multiple sclerosis is characterized by clearly defined flare-ups, followed by periods of remission. The flare-ups typically appear suddenly, last a few weeks or months, and then gradually disappear. Most people with MS have this form at the time of diagnosis. • Primary progressive. People with this less common form of multiple sclerosis experience a gradual decline, without periods of remission. People with this form of MS are usually older than 40 when signs or symptoms begin. • Secondary progressive. More than half the people with relapsing remitting MS eventually enter a stage of continuous deterioration referred to as secondary progressive MS. Sudden relapses may occur, superimposed upon the continuous deterioration that characterizes this type of multiple sclerosis. • Progressive relapsing. This is primary progressive MS with the addition of sudden episodes of new symptoms or worsened existing ones. This form is relatively uncommon. Risk factors These factors may increase your risk of developing multiple sclerosis: • Heredity. Multiple sclerosis is more common in people of Northern European descent. There also appears to be a genetic component to the condition, although the risk to children of people affected by MS is less than 5 percent over their lifetime. Researchers suspect that the tendency to develop multiple sclerosis is inherited, but the disease manifests only when environmental triggers are present. • Environmental factors. Environmental factors have some influence on multiple sclerosis. Many viruses and bacteria have been suspected of causing MS, most recently the Epstein-Barr virus, known also for causing infectious mononucleosis. Some studies have suggested that developing infection at a critical period of exposure may lead to conditions conducive to the development of MS a decade or more later. • Geographical factors. Multiple sclerosis is more common in countries with temperate climates, including Europe, southern Canada, northern United States, and southeastern Australia. The reason is unknown. When to seek medical advice One of the early indications of multiple sclerosis is numbness and tingling in your arms, legs or elsewhere in your body. Although numbness most often doesn't indicate MS, it's important to see your doctor if you experience numbness or tingling that persists for days or weeks — especially if it spreads to involve large parts of your body. Your doctor can determine whether MS or another neurological disorder may be the cause. Also see your doctor if you experience persistent double vision, persistent loss of balance or visual loss. Screening and diagnosis Multiple sclerosis can be difficult to diagnose. Many other conditions may produce symptoms similar to multiple sclerosis, but with a different prognosis and treatment. There are no specific tests for multiple sclerosis. Ultimately, the diagnosis relies on a determination that the clinical symptoms, radiological studies and laboratory studies suggest MS, and that no other condition provides a better explanation for them. Your doctor may base a multiple sclerosis diagnosis on the following:
  • 21. • Medical history. Your doctor reviews your signs and symptoms and their pattern. • Neurological examination. This examination systematically tests various parts of your nervous system, including your reflexes, muscle strength, muscle tone, and sensations of pain, heat, touch and vibration. Your doctor may also observe your gait, posture, coordination and balance, and ask you questions to help determine the clarity of your thinking, judgment and memory. • Magnetic resonance imaging (MRI) scan. The cylinder-shaped MRI scanner creates tissue-slice images on a computer from data generated by a powerful magnetic field and radio waves. Your doctor can view these images from any direction or plane. This imaging technique may reveal MS lesions, which are caused by myelin loss. An intravenous dye, gadolinium, will highlight "active" lesions that have developed within the past two months and this may help doctors know whether the MS is in an active phase, even if no symptoms are present indicating an attack of MS. Newer MRI techniques can provide even greater detail about the degree of nerve fiber injury or permanent myelin loss and recovery. • Spinal tap (lumbar puncture). In this procedure, a doctor or nurse removes a small sample of cerebrospinal fluid from within your spinal canal for laboratory analysis. This sample can show abnormalities associated with multiple sclerosis, such as abnormal levels of white blood cells or proteins. This procedure can also help rule out viral infections and other conditions that can cause neurological symptoms similar to those of MS. • Evoked potential test. This test measures the electrical signals sent by your brain in response to stimuli. An evoked potential test may use visual stimuli or electrical stimuli, in which short electrical impulses are applied to your legs or arms. Treatment If your attacks are mild or infrequent, your doctor may advise a wait-and-see approach, with counseling and observation. Medications for relapsing MS If you have a relapsing form of the disease, your doctor may recommend treatment with disease-modifying medications early in the course of disease. You can't take these medications if you're pregnant or may become pregnant. These medications for multiple sclerosis treatment include: • Beta interferons. Interferon beta-1b (Betaseron) and interferon beta-1a (Avonex, Rebif) are genetically engineered copies of proteins that occur naturally in your body. They help fight viral infection and regulate your immune system. If you use Betaseron, you inject yourself under your skin (subcutaneously) every other day. If you use Rebif, you inject yourself subcutaneously three times a week. You self-inject Avonex into your muscle (intramuscularly) once a week. These medications reduce but don't eliminate flare-ups of multiple sclerosis. It's uncertain which of their many actions lead to a reduction in disease activity and what their long-term benefits are. Beta interferons aren't used in combination with one another; only one of these medications is used at a time. The Food and Drug Administration (FDA) has approved beta
  • 22. interferons only for people with relapsing forms of MS who can still walk. Beta interferons don't reverse damage and haven't been proved to significantly alter long-term development of permanent disability. Some people develop antibodies to beta interferons, which may make them less effective. Other people can't tolerate the side effects, which may include symptoms similar to those of the flu (influenza). Doctors generally recommend beta interferons for people who have more than one attack of MS a year and for those who don't recover well from flare-ups. The treatment may also be used for people who have a significant buildup of new lesions as seen on an MRI scan, even when there may not be major new symptoms of disease activity. The FDA has approved the use of several beta interferons for people who've experienced a single attack that suggests multiple sclerosis, and who may be at risk of future attacks and developing definite MS. Risk of MS may also be suggested when an MRI scan of the brain shows lesions that predict a high risk of conversion to definite MS. Controversy exists as to whether these people should take these expensive and often inconvenient drugs for indefinite periods, especially because some people do well both in the short term and long term without therapy. Some doctors prefer to observe people at high risk with follow-up examinations and MRI scans to document any ongoing inflammatory disease activity before recommending long-term therapies such as beta interferon. • Glatiramer (Copaxone). This medication is an alternative to beta interferons if you have relapsing remitting MS. Doctors believe that glatiramer works by blocking your immune system's attack on myelin. You must inject glatiramer subcutaneously once daily. Side effects may include flushing and shortness of breath after injection. • Natalizumab (Tysabri). This drug is administered intravenously once a month. It works by blocking the attachment of immune cells to brain blood vessels — a necessary step for immune cells to cross into the brain — thus reducing the immune cells' inflammatory action on brain nerve cells. During clinical trials, this drug was shown to significantly reduce the frequency of attacks in people with relapsing MS. After receiving FDA approval, however, the drug was withdrawn from the market because of reports from three people who developed a rare, often fatal, brain disorder called progressive multifocal leukoencephalopathy. In 2006, after reconsideration of the drug's benefits for people with multiple sclerosis, the FDA agreed to allow the drug to be marketed again under specific conditions. Chief among these conditions is the requirement that doctors, pharmacists and patients be involved in a special distribution program known as TOUCH in order to prescribe, dispense or receive the drug. Because of the drug's risks, it's generally recommended only for people whose condition hasn't responded to other forms of MS therapy. Furthermore, there has been no study direct comparing natalizumab to existing treatments to prove whether it's superior to existing treatments. • Other medications. Mitoxantrone (Novantrone) is a chemotherapy drug used for many cancers. This drug is also FDA-approved for treatment of aggressive forms of relapsing remitting MS, as well as certain forms of progressive MS. It's given intravenously, typically every three months.
  • 23. Mitoxantrone may cause serious side effects, such as heart damage, after long-term use, so it's typically not used for longer than two to three years. And it's typically reserved for people with severe attacks or rapidly advancing disease who don't respond to other treatments. Close monitoring is critical for anyone on this medication. Some doctors are also prescribing other chemotherapy drugs, such as cyclophosphamide (Cytoxan), for people with severe, rapidly progressing MS. However, these medications aren't FDA-approved for treatment of MS. Medications for progressive MS Some medications may relieve symptoms of progressive MS. They include: • Corticosteroids. Doctors most often prescribe short courses of oral or intravenous corticosteroids to reduce inflammation in nerve tissue and to shorten the duration of flare-ups. Prolonged use of these medications, however, may cause side effects, such as osteoporosis and high blood pressure (hypertension), and the benefit of long-term therapy in multiple sclerosis isn't established. • Muscle relaxants. Baclofen (Lioresal) and tizanidine (Zanaflex) are oral treatments for muscle spasticity. If you have multiple sclerosis, you may experience muscle stiffening or spasms, particularly in your legs, which can be painful and uncontrollable. This typically occurs in people with persisting or progressive weakness of their legs. Baclofen may temporarily increase weakness in your legs. Tizanidine controls muscle spasms without causing your legs to feel weak, but can be associated with drowsiness or a dry mouth. • Medications to reduce fatigue. To help combat fatigue, your doctor may prescribe an antidepressant medication, the antiviral drug amantadine (Symmetrel) or a medication for narcolepsy called modafinil (Provigil). All drugs prescribed for this purpose appear to work because of their stimulant properties. One study has showed that aspirin treatment may be effective in controlling MS-related fatigue; further research is planned to address the benefits of aspirin on fatigue. • Other medications. Many medications are used for the muscle stiffness, depression, pain and bladder control problems associated with multiple sclerosis. Drugs for arthritis and medications that suppress the immune system may slow MS in some cases. MS treatments other than medications In addition to medications, these treatments also may be helpful: • Physical and occupational therapy. A physical or occupational therapist can teach you strengthening exercises and show you how to use devices that can ease the performance of daily tasks. Therapists are usually supervised by doctors (physiatrists) who advise and coordinate the therapy that you might receive. Therapists can assist you in finding optimal mobility assistance devices such as canes, wheelchairs and motorized scooters. These devices and exercises can help preserve your independence. • Counseling. Individual or group therapy may help you cope with multiple sclerosis and relieve emotional stress. Your family members or caregivers also may benefit from seeing a counselor. • Plasma exchange (plasmapheresis). Plasma exchange may help restore neurological function in people with sudden severe attacks of MS-related disability who don't respond to high doses of steroid
  • 24. treatment. This procedure involves removing some of your blood and mechanically separating the blood cells from the fluid (plasma). Your blood cells then are mixed with a replacement solution, typically albumin, or a synthetic fluid with properties like plasma. The solution with your blood is then returned to your body. Replacing your plasma may dilute the activity of the destructive factors in your immune system, including antibodies that attack myelin, and help you to recover. Plasma exchange has no proven benefit beyond three months from the onset of the neurological symptoms. Self-care These steps may help relieve some symptoms of multiple sclerosis: • Get enough rest. Fatigue is a common symptom of multiple sclerosis, and getting your rest may make you feel less tired. • Exercise. Regular aerobic exercise may offer some benefits if you have mild to moderate MS. Benefits include improved strength, muscle tone, balance and coordination, and help with depression. Swimming is a good option for people with MS who are bothered by heat. • Be careful with heat. Extreme heat may cause extreme muscle weakness. Although some people with multiple sclerosis aren't bothered by heat and may enjoy warm baths and showers, be very careful before exposing yourself to extreme heat until you know how you'll react. Don't get into a hot tub or sauna unless there's someone nearby who can pull you out if necessary. If you do experience heat- related worsening of signs or symptoms, cooling down for a few hours usually will return you to your normal state. • Cool down. Many people with multiple sclerosis experience heat- related worsening of MS symptoms. If you live in a hot and humid area, consider having air conditioning in your home. Tepid or cool baths also may provide some relief. • Eat a well-balanced diet. Eating a healthy, well-balanced diet can help keep your immune system strong. Coping skills As is true with other chronic diseases, living with multiple sclerosis can place you on a roller coaster of emotions. Here are some suggestions to help you even out the ups and downs: • Maintain normal daily activities as best you can. • Stay connected with friends and family. • Continue to pursue hobbies that you enjoy and are able to do. If multiple sclerosis impairs your ability to do things you enjoy, talk with your doctor about possible ways to get around the obstacles. Remember that your physical health can directly impact your mental health. Denial, anger and frustration are not uncommon when you learn life has dealt you something painful and unexpected. Professionals such as therapists or behavioral psychologists may help you put things in perspective. They can also teach you coping skills and relaxation techniques that may be helpful. Sometimes, joining a support group, where you can share experiences and feelings with other people, is a good approach. Ask your doctor what support groups are available in your community. Many chronic illnesses, including multiple sclerosis, are associated with an increased risk of depression. This isn't a failure to cope. Rather, depression may indicate a
  • 25. disruption in the body's neurochemistry that can be helped with appropriate medical treatment. If you have a chronic illness, such as MS, there's no denying that it affects your life. But how much you allow it to determine the quality of your life depends, to some extent, on the way you choose to live day to day. By Mayo Clinic Staff Dec 6, 2006 © 1998-2007 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "," "EmbodyHealth," "Reliable tools for healthier lives," "Enhance your life," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research. DS00188