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What is Wallenberg syndrome? Wallenberg syndrome is a rare condition in which an infarction, or stroke, occurs in the lateral medulla. The lateral medulla is a part of the brain stem. Oxygenated blood doesn’t get to this part of the brain when the arteries that lead to it are blocked. A stroke can occur due to this blockage. This condition is also sometimes called lateral medullary infarction. The cause of the syndrome isn’t always clear, however.
Esophageal varices are abnormal, enlarged veins in the tube that connects the throat and stomach (esophagus). This condition occurs most often in people with serious liver diseases. Esophageal varices develop when normal blood flow to the liver is blocked by a clot or scar tissue in the liver. To go around the blockages, blood flows into smaller blood vessels that aren't designed to carry large volumes of blood. The vessels can leak blood or even rupture, causing life-threatening bleeding. A number of drugs and medical procedures can help prevent and stop bleeding from esophageal varices.
A disease of the immune system due to infection with HIV. HIV destroys the CD4 T lymphocytes (CD4 cells) of the immune system, leaving the body vulnerable to life-threatening infections and cancers. Acquired immunodeficiency syndrome (AIDS) is the most advanced stage of HIV infection. To be diagnosed with AIDS, a person with HIV must have an AIDS-defining condition or have a CD4 count less than 200 cells/mm³ (regardless of whether the person has an AIDS-defining condition).
A cornea transplant, also called keratoplasty, is a surgical procedure to replace part of your cornea with corneal tissue from a donor. Your cornea is the transparent, dome-shaped surface of your eye that accounts for a large part of your eye's focusing power. A cornea transplant can restore vision, reduce pain and improve the appearance of a damaged or diseased cornea. Most cornea transplant procedures are successful. But cornea transplant carries a small risk of complications, such as rejection of the donor cornea.
A seizure occurs when there’s abnormal electrical activity in the brain. Seizures may go virtually unnoticed. Or, in severe cases, they may produce a change or loss of consciousness and involuntary muscle spasms called convulsions. Seizures usually come on suddenly and vary in duration and severity. A seizure may be a one-time event, or you may have seizures repeatedly. Recurrent seizures are called epilepsy, or a seizure disorder. Less than one in 10 people who has a seizure develops epilepsy. Experts classify seizures into two general categories and many subtypes based on the pattern of the attack. Generalized seizures involve both sides of the brain from the start of the attack. Common subtypes include tonic-clonic (grand mal) and absence seizures (petit mal). Febrile and infantile spasms are two types of generalized seizures that occur almost exclusively in young children. Partial (or focal) seizures are the second major seizure type. These begin in a specific area of the brain and may be contained there. Or they may spread to the entire brain. With simple partial seizures, the person remains conscious. Complex partial seizures involve impaired consciousness. What Causes Seizures? Often the cause of a seizure is unknown. Many conditions can provoke seizures, including: Stroke Brain tumors Head injuries Electrolyte imbalance Very low blood sugar Repetitive sounds or flashing lights, such as in video games Medications, such as antipsychotics and some asthma drugs Withdrawal from medications, such as Xanax, narcotics, or alcohol Use of drugs such as cocaine and heroin Cancer Brain infections, such as meningitis