injuries and poisoning
Intracranial Hematomas
Subdural Hematomas
Subdural hematomas are usually caused by bleeding from veins, including the bridging veins, located between the outer and middle layers of tissue covering the brain (meninges). Occasionally, subdural hematomas are caused by bleeding from arteries. Subdural hematomas may be Acute: Symptoms develop over minutes or a few hours after the injury. Subacute: Symptoms develop over several hours or days. Chronic: Symptoms develop gradually over weeks, months, or years. may be caused by rapid bleeding after a severe head injury. Acute subdural hematomas are often caused by a head injury that occurs during a fall or motor vehicle crash. They may also develop in people who have bruising in the brain (contusions) or an Epidural Hematomas . Acute subdural hematomas can cause swelling in the brain. The hematoma and swelling can result in increased pressure within the skull (intracranial pressure), which can make symptoms worse and increase the risk of dying. Chronic subdural hematomasare more common among people with alcohol use disorder, older people, and people who take medications that make blood less likely to clot (anticoagulants or antiplatelets). People with alcohol use disorder and older people, who are relatively prone to falls as well as bleeding, may ignore or forget minor to moderately severe head injuries. These injuries can lead to small subdural hematomas that may become chronic. By the time symptoms are noticeable, a chronic subdural hematoma may be very large. Chronic hematomas are less likely than acute hematomas to cause a rapid increase of pressure within the skull. In older people, the brain shrinks slightly, stretching the bridging veins and making them more likely to be torn if an injury, even a minor one, occurs. Also, bleeding tends to continue longer because the shrunken brain exerts less pressure on the bleeding vein, allowing more blood loss from it. Blood that remains after a subdural hematoma is slowly reabsorbed. After the blood is resorbed from a hematoma, the brain may not re-expand as well in older people as in younger people. As a result, a fluid-filled space (hygroma) may be left. The hygroma may refill with blood or enlarge because small vessels tear, causing repeated bleeding. An older person with symptoms of dementia may instead have a subdural hematoma, which can be effectively treated. Symptoms of a subdural hematoma may include a persistent headache, fluctuating drowsiness, confusion, memory changes, paralysis on the side of the body opposite the hematoma, and speech or language impairment. Other symptoms may occur depending on Brain Dysfunction by Location . In infants, a subdural hematoma can cause the head to enlarge (as in Hydrocephalus ) because the skull is soft and pliable. Therefore, pressure within the skull increases less in infants than it does in older children and adults. Computed tomography or magnetic resonance imaging Chronic subdural hematomas are more difficult to diagnose because of the length of time between the injury and the development of symptoms. An older person with gradually developing symptoms, such as memory impairment and drowsiness, may be mistakenly thought to have dementia. Computed tomography (CT) can detect acute, subacute, and many chronic subdural hematomas. Magnetic resonance imaging (MRI) is particularly accurate for diagnosis of chronic subdural hematomas. For small hematomas, often no treatment For large hematomas, surgery to drain them Often, small subdural hematomas in adults do not require treatment because the blood is absorbed on its own. If a subdural hematoma is large and is causing symptoms such as persistent headache, fluctuating drowsiness, confusion, memory changes, and paralysis on the opposite side of the body, doctors usually drain it surgically, sometimes by drilling a small hole in the skull. However, sometimes a larger opening must be made in the skull—for example, when bleeding has occurred very recently or when the blood may be too thick to drain through a small hole. During surgery, a drain is usually inserted and left in place for several days because subdural hematomas can recur. The person is monitored closely for recurrences. In infants, doctors usually drain the hematoma for cosmetic if for no other reasons. Only about 50% of people who are treated for a large acute subdural hematoma survive. People who are treated for a chronic subdural hematoma usually improve or do not worsen. 