<unk> s are most often caused by head injury, in which rapidly changing velocities within the skull may stretch and tear small bridging veins. Much more common than epidural hemorrhages,<unk>  hemorrhages generally result from shearing injuries due to various rotational or linear forces. There are claims that they can occur in cases of shaken baby syndrome, although there is no scientific evidence for this. They are also commonly seen in the elderly and in people with an alcohol use disorder who have evidence of cerebral atrophy. Cerebral atrophy increases the length the bridging veins have to traverse between the two meningeal layers, thus increasing the likelihood of shearing forces causing a tear. It is also more common in patients on anticoagulants or antiplatelet medications, such as warfarin and aspirin, respectively. People on these medications can have a<unk>  after a relatively minor traumatic event. Another cause can be a reduction in cerebrospinal fluid pressure, which can reduce pressure in the subarachnoid space, pulling the arachnoid away from the dura mater and leading to a rupture of the blood vessels. Risk factors Factors increasing the risk of a<unk>  include very young or very old age. As the brain shrinks with age, the<unk>  space enlarges and the veins that traverse the space must cover a wider distance, making them more vulnerable to tears. The elderly also have more brittle veins, making chronic<unk>  bleeds more common. Infants, too, have larger<unk>  spaces and are more predisposed to<unk>  bleeds than are young adults. It is often claimed that<unk>  is a common finding in shaken baby syndrome, although there is no science to support this. In juveniles, an arachnoid cyst is a risk factor for<unk> . Other risk factors include taking blood thinners (anticoagulants), long-term excessive alcohol consumption, dementia, and cerebrospinal fluid leaks.
Subdural hematoma
Hepatic encephalopathy
Subdural empyema
Epidural hematoma
Subarachnoid hemorrhage
ROSAH syndrome
Migraine
Migraine 