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Nervous system signs may change. Signs include: Coarse, "flapping" shaking of the hands when attempting to hold the arms out in front of the body and lift the hands; Abnormal mental status, particularly cognitive (thinking) tasks such as connectin...
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The diagnosis of encephalopathy depends on the presence of acute or chronic liver disease; altered mental state such as confusion, stupor, or coma; symptoms of central nervous system damage; and abnormal wave patterns on an encephalogram. Diagnost...
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Common tests that are used to evaluate liver function include: Albumin; Alpha-1 antitrypsin; ALP; ALT; AST; Gamma-glutamyl transpeptidase (GGT; Prothrombin time; Serum bilirubin; Urine bilirubin. Please see individual tests for details on how each...
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Liver function tests, or LFTs, include tests for bilirubin, a breakdown product of hemoglobin, and ammonia, a protein byproduct that is normally converted into urea by the liver before being excreted by the kidneys. LFTs also commonly include test...
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Detailed information on the most common liver function tests, including serum bilirubin test, serum albumin test, serum alkaline phosphatase test, serum aminotransferases, prothrombin time test, alanine transaminase test, aspartate transaminase test, gamm
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Liver function tests, or LFTs, include tests that are routinely measured in all clinical laboratories. LFTs include bilirubin, a compound formed by the breakdown of hemoglobin; ammonia, a breakdown product of protein that is normally converted int...
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Liver function tests, or LFTs, include tests that are routinely measured in all clinical laboratories. LFTs include bilirubin, a compound formed by the catabolism of hemoglobin; ammonia, a product of protein catabolism that is normally converted i...
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During a physical examination, a health care provider studies a patient's body to determine the presence or absence of physical problems. A typical physical examination includes: Inspection (looking at the body; Palpation (feeling the body with ha...
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The health status of populations and of individuals is assessed for many reasons. Assessing needs for care helps guide the allocation of resources— diagnostic assessments guide treatment, prognostic assessments contribute to planning, and assessin...
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A cranial computed tomography (CT) scan is an imaging method that uses x-rays to create cross-sectional pictures of the head, including the skull, brain, eye sockets, and sinuses. See: Computed tomography
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Computed tomography (CT) scans are completed with the use of a 360-degree x-ray beam and computer production of images. These scans allow for cross-sectional views of body organs and tissues. Computed tomography is also known as computerized axial...
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Injury to the head may damage the scalp, skull , or brain . The most important consequence of head injury is traumatic brain injury. Head injury may occur either as a closed head injury such as the head hitting a car's windshield, or as a penetrat...
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Computed tomography (CT) scans are completed with the use of a 360-degree x-ray beam and computer production of images. These scans allow for cross- sectional views of body organs and tissues.
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Injury to the head may damage the scalp, skull or brain. The most important consequence of head trauma is traumatic brain injury. Head injury may occur either as a closed head injury, such as the head hitting a car's windshield, or as a penetratin...
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Head injury is an injury to the scalp, skull, or brain. The most important consequence of head trauma is traumatic brain injury. Head injury may occur either as a closed head injury, such as the head hitting a car's windshield; or as a penetrating...
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CT imaging equipment includes conventional, spiral, multi-slice, and electron-beam computed tomography full-body scanners, which use x rays to acquire cross-sectional images and computer workstations to reconstruct acquired image data for display ...
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A blood glucose test measures the amount of sugar (glucose) in a sample of your blood. See also: Glucose test - CSF; Glucose test - urine; Home blood glucose monitoring.
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Glucose tests are used to determine the concentration of glucose in blood , urine, cerebrospinal fluid, and other body fluids. These tests are used to detect an increased blood glucose (hyperglycemia), a decreased blood glucose (hypoglycemia), inc...
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AST (aspartate aminotransferase) is an enzyme found in high amounts in heart muscle and liver and skeletal muscle cells. It is also found in lesser amounts in other tissues. This article discusses the test to measure the amount of AST in the blood.
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The Aspartate aminotransferase test measures levels of AST, an enzyme released into the blood when certain organs or tissues, particularly the liver and heart, are injured. Aspartate aminotransferase (AST) is also known as serum glutamic oxaloacet...
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Bilirubin is a yellowish pigment found in bile, a fluid produced by the liver. This article discusses the laboratory test done to measure bilirubin in the blood. Total and direct bilirubin are usually measured to screen for or to monitor liver or ...
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Monitors the liver function of newborns. The bilirubin test is a blood test to monitor the liver function of newborns. The rapid destruction of red blood cells after birth produces more bilirubin than the infant's liver can handle, causing some ja...
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Alanine transaminase (ALT) is an enzyme found in the highest amounts in the liver. Injury to the liver results in release of the substance into the blood. This article discusses the test to measure the amount of ALT in the blood.
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Alkaline phosphatase (ALP) is a protein found in all body tissues. Tissues with particularly high amounts of ALP include the liver, bile ducts, and bone. A blood test can be done to measure the level of ALP. See also: ALP isoenzyme test
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Alkaline phosphatase is an enzyme found throughout the body. Like all enzymes, it is needed, in small amounts, to trigger specific chemical reactions. When it is present in large amounts, it may signify bone or liver disease or a tumor.
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Albumin is a protein made by the liver. A serum albumin test measures the amount of this protein in the clear liquid portion of the blood.
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Prothrombin time (PT) is a blood test that measures the time it takes for the liquid portion (plasma) of your blood to clot. See also: Partial thromboplastin time (PTT)
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The prothrombin time test belongs to a group of blood tests that assess the clotting ability of blood. The test is also known as the pro time or PT test.
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Hemostasis has been described as "a process by which the body spontaneously stops bleeding and maintains blood in the fluid state within the vascular compartment." There are at least four major systems that are involved in this complex process: th...
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This test roughly measures the types of protein in the fluid (serum) part of a blood sample. See also: Immunoelectrophoresis - serum; Immunofixation - serum; Serum globulin electrophoresis.
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Electrophoresis is a technique used to separate the different components (fractions) of a mixture, such as proteins in a biological sample. Separation is based on differences in the charge (and sometimes size) of the molecules, which determines th...
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Electrophoresis is a technique used to separate different elements (fractions) of a blood sample into individual components. Serum protein electrophoresis (SPEP) is a screening test that measures the major blood proteins by separating them into fi...
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Gamma-glutamyl transpeptidase (GGT) is a test to measure the amount of the enzyme GGT in the blood.
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A platelet count is a test to measure how many platelets you have in your blood. Platelets help the blood clot. They are smaller than red or white blood cells.
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A platelet count is a diagnostic test that determines the number of platelets in the patient's blood. Platelets, which are also called thrombocytes, are small disk-shaped blood cells produced in the bone marrow and involved in the process of blood...
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A magnetic resonance imaging (MRI) scan of the head is a noninvasive method to create detailed pictures of the brain and surrounding nerve tissues. Unlike x-rays and computed tomographic (CT) scans, which use radiation, MRI uses powerful magnets a...
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Brain abscess is a bacterial infection within the brain.
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A brain biopsy is the removal of a small piece of brain tissue for the diagnosis of abnormalities of the brain, such as Alzheimer's disease , tumors, infection, or inflammation.
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A brain tumor is an abnormal growth of tissue in the brain. Unlike other tumors, brain tumors spread by local extension and rarely metastasize (spread) outside the brain. A benign brain tumor is composed of non-cancerous cells and does not metasta...
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Congenital brain defects are a group of disorders of brain development.
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The brain is the part of the central nervous system located in the skull. It controls the mental processes and physical actions of a human being.
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The brain is a large mass of soft nervous tissue made up of both neurons and supporting glial cells lying within the cranium of the skull. The brain contains both gray and white matter. Gray matter is primarily nerve cell bodies, whereas white mat...
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Magnetic resonance imaging (MRI) scanners rely on the principles of atomic nuclear-spin resonance. Using strong magnetic fields and radio waves, MRI collects and correlates deflections caused by atoms into images. MRIs (magnetic resonance imaging ...
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Traumatic brain injury (TBI) is the result of physical trauma to the head causing damage to the brain. This damage can be focal, or restricted to a single area of the brain, or diffuse, affecting more than one region of the brain. By definition, T...
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The brain is the part of the central nervous system (CNS) inside the skull (the part outside the skull is the spinal cord ). It gives rise to cognitive thought processes and controls various body functions including muscular activity, speech, sigh...
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A brain tumor is an abnormal growth of tissue, either malignant (cancerous) or benign (noncancerous), in the brain. Each year, more than 17,000 brain tumors are diagnosed in the United States.
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Congenital brain defects are a group of disorders of brain development that are present at birth.
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Part of the central nervous system located in the skull. Controls mental and physical actions of the organism. The brain, with the spinal cord and network of nerves, controls information flow throughout the body, voluntary actions, such as walking...
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Like all other parts of the body, the brain and central nervous system are made up of cells that ordinarily grow and divide to create new cells as needed. This is usually an orderly process; but when cells lose their ability to grow normally or to...
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Magnetic resonance imaging (MRI) is a noninvasive way to take pictures of the body. Unlike x-rays and computed tomographic (CT) scans, which use radiation, MRI uses powerful magnets and radio waves. The MRI scanner contains the magnet. The magneti...
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Cardiac nuclear imaging is also called a "perfusion scan.” A radioactive tracer is delivered into the bloodstream. Then a camera scans the tracer in the blood as it flows through the heart muscle.
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New MRI machines and new techniques result in images that show prostate cancer in much greater detail, allowing biopsies to be targeted more precisely, and thus cancer staging can be more accurate as well.
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Detailed information on magnetic resonance imaging, including how the image is performed and what happens following the procedure
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Magnetic resonance imaging (MRI) is a test that lets your doctor see detailed pictures of the inside of your body. MRI combines the use of strong magnets and radio waves to form an MRI image.
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A Harvard Medical School physician answers your question about the safety of MRIs for those who have stents.
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Studies have found that MRI tests used in addition to mammography detected more cancers in women at high risk for breast cancer. Women at average risk would not necessarily benefit from the additional testing.
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When I had an MRI of my knee, I was told the test was dangerous for people who have metal devices in their bodies. Since then, I developed angina and my cardiologist put in a metal stent. If I need an MRI in the future, will I be able to get one?
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For women at high genetic risk, adding MRI screening to mammography may improve early detection of breast cancer.
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Is a regular MRI more accurate then an open MRI?
Diana Post, M.D., is an assistant professor of medicine at Harvard Medical School and a member of the Department of Medicine at Brigham and Women's Hospital.
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How safe is it for a baby who is 6 months old to have an MRI?
Claire McCarthy, M.D., is a senior medical editor for Harvard Health Publications. She is an instructor in pediatrics at Harvard Medical School, an attending physician at Children's Hospital of Boston, and co-director of the pediatrics department at Martha Eliot Health Center, a neighborhood health service of Children's Hospital. The author of two books, "Learning How the Heart Beats" and "Everyone's Children", Dr. McCarthy was a regular columnist for "Sesame Street Parents Magazine" from 1995 to 1998 and is currently a contributing editor for "Parenting Magazine".
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Persons with pacemakers cannot get an MRI because it conflicts with the pacemaker's function. Future pacemakers will likely be made MRI-safe, but this will probably take at least several more years.
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MRI produces a map of hydrogen atoms distributed in the body. Hydrogen is the simplest element known, the most abundant in biological tissue, and one that can be magnetically polarized. It will align itself within a strong magnetic field, like the...
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Magnetic resonance imaging (MRI) is a unique and versatile medical imaging modality. Doctors can obtain highly refined images of the body's interior using MRI. By using strong magnetic fields and pulses of radio waves to manipulate the natural mag...
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Magnetic resonance imaging (MRI) is one of the newest diagnostic medical imaging technologies that uses strong magnets and pulses of radio waves to manipulate the natural magnetic properties in the body to generate a visible image. In the field of...
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Magnetic resonance imaging (MRI) is the newest, and perhaps most versatile, medical imaging technology available. Doctors can get highly refined images of the body's interior without surgery, using MRI. By using strong magnets and pulses of radio ...
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Magnetic resonance imaging (MRI) is a diagnostic imaging procedure that uses radio waves, a magnetic field, and a computer to generate images of the anatomy.
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Magnetic resonance imaging (MRI) is one of the newest, and perhaps most versatile, medical imaging technology available. Doctors can get highly refined images of the body's interior without surgery using MRI. By using strong magnets and pulses of ...
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Detailed information on magnetic resonance imaging (MRI), including information on how the procedure is performed
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People with certain kinds of pacemakers or ICDs can safely undergo an MRI, as long as a series of safety precautions is carefully followed.
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A computed tomography (CT) scan is an imaging method that uses x-rays to create cross-sectional pictures of the body. See also: Cranial CT scan; Lumbosacral spine CT scan; Orbit CT scan; Thoracic CT scan.
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Computed tomography (CT) is a test that combines x-rays and computer scans. The result is a detailed picture that can show problems with soft tissues (such as the lining of your sinuses), organs (such as your kidneys or lungs), and bones.
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Detailed information on CT scan, including how the CT scan is performed and what happens after the procedure
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Detailed information on computed tomography scans, also called CT scan or CAT scan, including information on how the procedure is performed
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Detailed information on ultrafast computed tomography scans, also called ultrafast CT scan or ultrafast CAT scan, including information on how the procedure is performed
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Detailed information on ultrafast computed tomography (CT) scan, including reasons for the procedure, risks of the procedure, what to expect, and discharge instructions
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Computed tomography (CT) scanning is a valuable diagnostic tool that provides physicians with views of internal body structures. During a CT scan, multiple x rays are passed through the body, producing cross-sectional images, or "slices, " on a ca...
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Computed tomography (CT), formerly referred to as computerized axial tomography (CAT), is a common diagnostic imaging procedure that uses x rays to generate images (slices) of the anatomy.
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Computed tomography (CT) scans are completed with the use of a 360-degree x-ray beam and computer production of images. These scans allow for cross-sectional views of body organs and tissues.
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Computed tomography scanning, also called CT scan, CAT scan, or computerized axial tomography, is a diagnostic tool that provides views of internal body structures using x rays. In the field of mental health, a CT scan may be used when a patient s...
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Computed tomography (also known as CT, CT scan, CAT, or computerized axial tomography) scans use x rays to produce precise cross-sectional images of anatomical structures.
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What is the difference between a pelvic CT scan and an abdominal CT scan?
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Is there an alternative to iodine as a contrast medium in a CT scan?
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A complete blood count (CBC) test measures the following: The number of red blood cells (RBCs; The number of white blood cells (WBCs; The total amount of hemoglobin in the blood; The fraction of the blood composed of red blood cells (hematocrit; T...
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One of the most commonly ordered clinical laboratory tests, a blood count, also called a complete blood count (CBC), is a basic evaluation of the cells (red blood cells, white blood cells, and platelets) suspended in the liquid part of the blood (...
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A complete blood count (CBC) is a series of tests used to evaluate the composition and concentration of the cellular components of blood. It consists of the following tests: red blood cell (RBC) count, white blood cell (WBC) count, and platelet co...
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A complete blood count (CBC) is a series of tests used to evaluate the composition and concentration of the cellular components of blood. It consists of the following tests: red blood cell (RBC) count, white blood cell (WBC) count, and platelet co...
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The clinical laboratory test that evaluates the three main cellular components of peripheral blood (red cells, white cells, and platelets) is called the "complete blood count" (CBC). It is used commonly to assess whether a patient is anemic (low r...
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Kidney function tests are common procedures used to evaluate kidney (renal) function. Refer to the following documents for details of how each test is performed: BUN; Creatinine - blood; Creatinine clearance; Creatinine - urine.
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Kidney function tests are a cadre of tests that are used to screen for and manage renal disease. Tests commonly used for this purpose are plasma creatinine, blood urea nitrogen (BUN), electrolytes, and routine urinalysis . Additional laboratory te...
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Kidney function tests is a collective term for a variety of individual tests and procedures that can be done to evaluate how well the kidneys are functioning. A doctor who orders kidney function tests and uses the results to assess the functioning...
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Kidney function tests is a collective term for a variety of individual tests and procedures that can be done to evaluate how well the kidneys are functioning.
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The hepatitis virus panel is a series of blood tests used to detect current or past infection by hepatitis A, hepatitis B, or hepatitis C. It can screen blood samples for more than one kind of hepatitis virus at the same time. Antibody and antigen...
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