Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
A stroke results from impaired oxygen
delivery to brain cells via the bloodstream.
According to the U.S. National Institute of
Neurological Disorders and Stroke, the five
major signs of stroke are the sudden onset of:
Numbness or weakness of the face, arm or
leg, especially on one side of the body. The
loss of voluntary movement and/or sensation may
be complete or partial. There may also be an
associated tingling sensation in the affected
area.
Confusion, trouble speaking or
understanding. Sometimes weakness in the muscles
of the face can cause drooling.
Trouble seeing in one or both eyes
Trouble walking, dizziness, loss of
balance or coordination
Reference: U.S. National Institute of Neurological Disorders and Stroke
What is a stroke?
Brain cell function requires a constant delivery of oxygen and glucose from the bloodstream. A stroke, or cerebrovascular accident (CVA), occurs when blood supply to part of the brain is disrupted, causing brain cells to die. Blood flow can be compromised by a variety of mechanisms.
Blockage of an artery
Narrowing of the small arteries within the brain can cause a lacunar stroke, (lacune
means "empty space"). Blockage of a single arteriole can affect a tiny area of brain causing that tissue to
die (infarct).
Hardening of the arteries (atherosclerosis) leading to the brain. There are four major blood vessels that supply the brain with blood.
The anterior circulation of the brain that controls most motor activity, sensation, thought, speech, and emotion is supplied by the carotid arteries.
The posterior circulation, which supplies the brainstem and the cerebellum, controlling the automatic parts of brain function and coordination, is supplied by the vertebrobasilar arteries.
If these arteries become narrow as a result of
atherosclerosis, plaque or
cholesterol, debris can break off and float downstream, clogging the blood supply to a part of the brain. As opposed to lacunar strokes, larger parts of the brain can lose blood supply, and this may produce more symptoms than a lacunar stroke.
Embolism to the brain from the heart. In some instances
blood clots can form within the heart
and the potential exists for them to break off and travel (embolize) to the arteries in the brain and cause a stroke.
Rupture of an artery (hemorrhage)
Cerebral hemorrhage (bleeding within the brain substance). The most common reason to have bleeding within the brain is uncontrolled high blood pressure. Other situations include
aneurysms that leak or rupture or arteriovenous malformations (AVM) in which there is an abnormal collection of blood vessels that are fragile and can bleed.
What causes a stroke?
Blockage of an artery
The blockage of an artery in the brain by a clot (thrombosis) is the most common cause of a stroke. The part of the brain that is supplied by the clotted blood vessel is then deprived of blood and oxygen. As a result of the deprived blood and oxygen, the cells of that part of the brain die and the part of the body that it controls stops working. Typically, a cholesterol plaque in a small blood vessel within the brain that has gradually caused blood vessel narrowing ruptures and starts the process of forming a small blood clot.
Risk factors for narrowed blood vessels in the brain are the same as those that cause narrowing blood vessels in the heart and heart attack (myocardial infarction). These risk factors include:
Another type of stroke may occur when a blood clot or a piece of atherosclerotic plaque (cholesterol and calcium deposits on the wall of the inside of the heart or artery) breaks loose, travels through the bloodstream and lodges in an artery in the brain. When blood flow stops, brain cells do not receive the oxygen and glucose they require to function and a stroke occurs. This type of stroke is referred to as an embolic stroke. For example, a blood clot might originally form in the heart chamber as a result of an
irregular heart rhythm, such as occurs in
atrial fibrillation. Usually, these clots remain attached to the inner lining of the heart, but occasionally they can break off, travel through the blood stream, form a plug (embolism) in a brain artery, and cause a stroke. An embolism can also originate in a large artery (for example, the carotid artery, a major artery in the neck that supplies blood to the brain) and then travel downstream to clog a small artery within the brain.
Cerebral hemorrhage
A cerebral hemorrhage occurs when a blood vessel in the brain ruptures and bleeds into the surrounding brain tissue. A cerebral hemorrhage (bleeding in the brain) causes stroke symptoms by depriving blood and oxygen to parts of the brain in a variety of ways. Blood flow is lost to some cells. As well, blood is very irritating and can cause swelling of brain tissue (cerebral edema).
Edema and the accumulation of blood from a cerebral hemorrhage increases pressure within the skull and causes further damage by squeezing the brain against the bony skull further decreasing blood flow to brain tissue and cells.
Subarachnoid hemorrhage
In a subarachnoid hemorrhage, blood accumulates in the space beneath the arachnoid membrane that lines the brain. The blood originates from an abnormal blood vessel that leaks or ruptures. Often this is from an aneurysm (an abnormal ballooning out of the wall of the vessel). Subarachnoid hemorrhages usually cause a sudden, severe headache,
nausea, vomiting, light intolerance, and a stiff neck. If not recognized and treated, major neurological consequences, such as coma, and brain death
may occur.
Vasculitis
Another rare cause of stroke is vasculitis, a condition in which the blood vessels become inflamed
causing decreased blood flow to brain tissue.
Migraine headache
There appears to be a very slight increased occurrence of stroke in people with
migraine headache. The mechanism for migraine or vascular headaches includes narrowing of the brain blood vessels. Some migraine headache episodes can even mimic stroke with loss of function of one side of the body or vision or speech problems. Usually, the symptoms resolve as the headache resolves.
Night sweats are severe hot flashes that occur at night and result in a drenching sweat. In order to distinguish night sweats that arise from medical causes from those that occur because one's surroundings are too warm, doctors generally refer to true night sweats as severe hot flashes occurring at night that can drench sleepwear and sheets, which are not related to an overheated environment.
High blood pressure, also known as hypertension, is a repeatedly
elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above
140 with a diastolic pressure above 90. There are two causes of high blood pressure, primary and secondary. Primary high blood pressure is much more common that secondary and its basic causes or underlying defects are not always known. It is known that a diet high in salt increases the risk for high blood pressure, as well as high cholesterol. Genetic factors are also a primary cause. Secondary high blood pressure is generally caused by another condition such as renal hypertension, tumors, and other conditions. Treatment for high blood pressure is generally lifestyle changes and if necessary, diet.
Dizziness is a symptom that is often applies to a variety of sensations including lightheadedness and vertigo. Causes of dizziness include low blood pressure, heart problems, anemia, dehydration, and more. Treatment of dizziness depends on the cause.
Migraine is usually periodic attacks of headaches on one or both sides of the head. These may be accompanied by nausea, vomiting, increased sensitivity of the eyes to light (photophobia), increased sensitivity to sound (phonophobia), dizziness, blurred vision, cognitive disturbances, and other symptoms. Treatments for migraine headache include therapies that may or may not involve medications.
Diabetes mellitus is a chronic condition characterized by high levels of sugar (glucose) in the blood. The two types of diabetes are referred to as type 1 (insulin dependent) and type 2 (non-insulin dependent). Symptoms of diabetes include increased urine output, thirst, hunger, and fatigue. Treatment of diabetes depends on the type.
A pulmonary embolism occurs when a piece of a blood clot from deep vein thrombosis (DVT) breaks off and travels to an artery in the lung where it blocks the artery and damages the lung. The most common symptoms of a pulmonary embolism are shortness of breath, chest pain, and a rapid heart rate.
Deep vein thrombosis (DVT) is a blood clot in a vein located deep in the muscles of the legs, thighs, pelvis (lower torso), or arms. The most common symptoms of a deep vein thrombosis are swelling and pain in the leg that has the blood clot. A DVT is difficult to diagnose without specific tests in which the deep vein system can be examined.
Cholesterol is naturally produced by the body, and is a building block for cell membranes and hormones. Low-density lipoprotein (LDL) cholesterol is the "bad" cholesterol, conversely, high-density lipoprotein (HDL) cholesterol is the "good" cholesterol. High cholesterol treatment includes lifestyle changes (diet and exercise), and medications such as statins, bile acid resins, and fibric acid derivatives.
Dementia is a significant loss of intellectual abilities such as memory capacity, severe enough to interfere with social or occupational functioning. There are different criteria classification schemes for dementias such as cortical, subcortical, progressive, primary, and secondary dementias. Other conditions and medication reactions can also cause dementia. Dementia is diagnosed based on a certain set of criteria. Treatment for dementia is generally focused on the symptoms of the disease.
Fainting, also referred to as blacking out, syncope, or temporary loss of consciousness has many causes. Often a person will have signs or symptoms prior to the fainting episode. Diagnosis and treatment depends upon the cause of the fainting or syncope episode.
Heart attack happens when a blood clot completely obstructs a coronary
artery supplying blood to the heart muscle. A heart attack can cause chest pain, heart failure, and electrical
instability of the heart.
A hematoma is a collection of blood that is outside a blood vessel. There are different areas where hematomas occur including the inside the skull, scalp, ear, septum, bones, finger and toenails, and intra-abdominal. Treatment for hematomas depend on the type and location of the hematoma.
Internal bleeding occurs when an artery or vein is damaged and blood to escapes the circulatory system and collects inside the body. Internal bleeding can be caused by a variety of situations such as blunt trauma, deceleration trauma, medications, fractures, and spontaneous bleeding. Treatment of internal bleeding depends on the cause of the bleeding.
Brain aneurysm (cerebral aneurysm) is caused by microscopic damage to artery walls, infections of the artery walls, tumors, trauma, drug abuse. Symptoms include headache, numbness of the face, dilated pupils, changes in vision, the "worst headache of your life," or a painful stiff neck. Immediate treatment for a brain aneurysm is crucial for patient survival.
Laryngitis is an inflammation of the voice box (vocal cords). The most common cause of acute laryngitis is infection, which inflames the vocal cords. Symptoms may vary from degree of laryngitis and age of the patient. Common symptoms include croup, hoarse cough, fever, cold, runny nose, dry cough, and loss of voice. Chronic laryngitis generally lasts more than three weeks. Causes other than infection include smoking, excess coughing, GERD, and more. Treatment depends on the cause of laryngitis.
Epilepsy is a brain disorder in which the person has seizures. There are two kinds of seizures, focal and generalized. There are many causes of epilepsy. Treatment of epilepsy (seizures) depends upon the cause and type of seizures experienced.
Overactive bladder is a sudden involuntary contraction of the muscle wall of the bladder causing urinary urgency (an immediate unstoppable need to urinate). Overactive bladder is is a form of urinary incontinence. Treatment options may include Kegel exercises, biofeedback, vaginal weight training, pelvic floor electrical stimulation, behavioral therapy, and medications.
Heart rhythm disorders vary from minor palpitations, premature atrial contractions (PACs), premature ventricular contractions (PVCs), sinus tachycardia, and sinus brachycardia, to abnormal heart rhythms such as tachycardia, ventricular fibrillation, ventricular flutter, atrial fibrillation, atrial flutter, paroxysmal supraventricular tachycardia (PSVT), Wolf-White-Parkinson syndrome, brachycardia, or heart blocks. Treatment is dependant upon the type of heart rhythm disorder.
Hydrocephalus is an abnormal buildup of cerebrospinal fluid (CSF) in the ventricles of the brain. The fluid is often under increased pressure and can compress and damage the brain. Symptoms of hydrocephalus vary with age, progression of the disease, and individual tolerance to the condition. Hydrocephalus is most often treated by surgery in which a shunt system is inserted.
Dysphagia or difficulty in swallowing, swallowing problems. Dysphagia is due to problems in nerve or muscle control. It is common, for example, after a stroke. Dysphagia compromises nutrition and hydration and may lead to aspiration pneumonia and dehydration.
Heart disease (coronary artery disease) is caused by a buildup of cholesterol deposits in the coronary arteries. Risk factors for heart disease include smoking, high blood pressure, heredity, diabetes, peripheral artery disease, and obesity. Symptoms include chest pain and shortness of breath. There are a variety of tests used to diagnose coronary artery disease. Treatment includes life-style changes, medications, procedures, or surgery.
Obesity is the state of being well above one's normal weight. A person has traditionally been
considered to be obese if they are more than 20 percent over their ideal weight.
That ideal weight must take into account the person's height, age, sex, and
build.
Optic neuritis is inflammation of the optic nerve, the structure that connects the eye to the brain. The precise cause of optic neuritis is unknown, but it is thought to be a type of autoimmune disorder. Optic neuritis most commonly develops due to an autoimmune disorder that may be triggered by a viral infection.
Cerebral palsy (CP) is an abnormality of motor function and postural tone acquired at an early age (even before birth). Cerebral palsy is generally caused by brain trauma. Types of cerebral palsy include: spastic, choreoathetoid, and hypotonic. There is no cure for cerebral palsy, and treatment is generally managing the symptoms of the condition.
Hypothermia is having a body core temperature of less than 35 C or 95 F. Most causes of hypothermia are preventable. Risk factors for hypothermia include age, mental status, medical conditions, and medications. Symptoms of hypothermia generally depend upon the severity of the condition. Treatment depends upon the severity of hypothermia. If not treated early, hypothermia can lead to cardiac arrest, coma, or death.
Coma is the inability to waken or react to the surrounding environment. The Glasgow Coma Scale is frequently used to measure the depth of coma. Causes of coma include trauma, bleeding, edema, lack of oxygen, poisoning, or hypoglycemia. Prognosis for a patient in a coma depends on the cause of the coma.
When a portion of the brain loses blood supply, through a blood clot or embolus, a transient ischemic attack (TIA, mini-stroke) may occur. If the symptoms do not resolve, a stroke most likely has occurred. Symptoms of TIA include: confusion, weakness, lethargy, and loss of function to one side of the body. Risk factors for TIA include vascular disease, smoking, high blood pressure, high cholesterol, and diabetes. Treatment depends upon the severity of the TIA, and whether it resolves.
Hoarseness (abnormal deep, harsh, raspy voice) is caused by a variety of conditions in which the larynx (voice box and vocal chords) are irritated or injured. Examples of causes of hoarseness include: laryngitis, straining the vocal cords by yelling or screaming, infections, GERD, allergies, and more. Treatment of hoarseness depends on the cause.
While the patient's history and physical examination are the building blocks
of making a medical diagnosis, the ability to peer inside the body can be a
powerful tool. Ultrasound is an imaging technique that provides that
ability to medical practitioners.
What is an ultrasound?
Ultrasound produces sound waves that are beamed into the body causing return
echoes that are recorded to "visualize" structures beneath the skin. The ability
to measure different echoes reflected from a variety of tissues allows a shadow
picture to be constructed. The technology is especially accurate at seeing the
interface between solid and fluid filled spaces. These are actually the same
principles that allow SONAR on boats to see the bottom of the ocean.
What is ultrasonography?
Ultrasonography is body imaging using ultrasound in medical diagnosis. A
skilled ultrasound technician is able to...