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Nontraumatic intraparenchymal hemorrhage most commonly results from hypertensive damage to blood vessel walls e.g.:
- hypertension
- eclampsia
- drug abuse,
but it also may be due to autoregulatory dysfunction with excessive cerebral blood flow e.g.:
- reperfusion injury
- hemorrhagic transformation
- cold exposure
- rupture of an aneurysm or arteriovenous malformation (AVM)
- arteriopathy (e.g. cerebral amyloid angiopathy, moyamoya)
- altered hemostasis (e.g. thrombolysis, anticoagulation, bleeding diathesis)
- hemorrhagic necrosis (e.g. tumor, infection)
- venous outflow obstruction (e.g. cerebral venous sinus thrombosis).
Nonpenetrating and penetrating cranial trauma can also be common causes of intracerebral hemorrhage.
Intracerebral bleeds are the second most common cause of stroke, accounting for 10% of hospital admissions for stroke. High blood pressure raises the risks of spontaneous intracerebral hemorrhage by two to six times. More common in adults than in children, intraparenchymal bleeds are usually due to penetrating head trauma, but can also be due to depressed skull fractures. Acceleration-deceleration trauma, rupture of an aneurysm or arteriovenous malformation (AVM), and bleeding within a tumor are additional causes. Amyloid angiopathy is a not uncommon cause of intracerebral hemorrhage in patients over the age of 55. A very small proportion is due to cerebral venous sinus thrombosis.
Risk factors for ICH include:
- Hypertension (high blood pressure)
- Diabetes mellitus
- Menopause
- Cigarette smoking
- Excessive alcohol consumption
- Severe migraine
Traumautic intracerebral hematomas are divided into acute and delayed. Acute intracerebral hematomas occur at the time of the injury while delayed intracerebral hematomas have been reported from as early as 6 hours post injury to as long as several weeks.
The incidence of RCVS is unknown, but it is believed to be "not uncommon", and likely under-diagnosed. One small, possibly biased study found that the condition was eventually diagnosed in 45% of outpatients with sudden headache, and 46% of outpatients with thunderclap headache.
The average age of onset is 42, but RCVS has been observed in patients aged from 19 months to 70 years. Children are rarely affected. It is more common in females, with a female-to-male ratio of 2.4:1.
In younger patients, vascular malformations, specifically AVMs and cavernous angiomas are more common causes for hemorrhage. In addition, venous malformations are associated with hemorrhage.
In the elderly population, amyloid angiopathy is associated with cerebral infarcts as well as hemorrhage in superficial locations, rather than deep white matter or basal ganglia. These are usually described as "lobar". These bleedings are not associated with systemic amyloidosis.
Hemorrhagic neoplasms are more complex, heterogeneous bleeds often with associated edema. These hemorrhages are related to tumor necrosis, vascular invasion and neovascularity. Glioblastomas are the most common primary malignancies to hemorrhage while thyroid, renal cell carcinoma, melanoma, and lung cancer are the most common causes of hemorrhage from metastatic disease.
Other causes of intraparenchymal hemorrhage include hemorrhagic transformation of infarction which is usually in a classic vascular distribution and is seen in approximately 24 to 48 hours following the ischemic event. This hemorrhage rarely extends into the ventricular system.
Susceptibility weighted imaging has been proposed as a tool for identifying CAA-related microhemorrhages.
Biopsies also play a role in diagnosing the condition.
Prognostics factors:
Lower Glasgow coma scale score, higher pulse rate, higher respiratory rate and lower arterial oxygen saturation level is prognostic features of in-hospital mortality rate in acute ischemic stroke.
The direct cause of the symptoms is believed to be either constriction or dilation of blood vessels in the brain. The pathogenesis is not known definitively, and the condition is likely to result from multiple different disease processes.
Up to two-thirds of RCVS cases are associated with an underlying condition or exposure, particularly vasoactive or recreational drug use, complications of pregnancy (eclampsia and pre-eclampsia), and the adjustment period following childbirth called "puerperium". Vasoactive drug use is found in about 50% of cases. Implicated drugs include selective serotonin reuptake inhibitors, weight-loss pills such as Hydroxycut, alpha-sympathomimetic decongestants, acute migraine medications, pseudoephedrine, epinephrine, cocaine, and cannabis, among many others. It sometimes follows blood transfusions, certain surgical procedures, swimming, bathing, high altitude experiences, sexual activity, exercise, or coughing. Symptoms can take days or a few months to manifest after a trigger.
Following a study and publication in 2007, it is also thought SSRIs, uncontrolled hypertension, endocrine abnormality, and neurosurgical trauma are indicated to potentially cause vasospasm.
It is usually associated with amyloid beta.
However, there are other types:
- the "Icelandic type" is associated with Cystatin C
- the "British type" is associated with ITM2B
Research is currently being conducted to determine if there is a link between cerebral amyloid angiopathy and ingestion of excessive quantities of aluminum.
In an ischemic stroke, blood supply to part of the brain is decreased, leading to dysfunction of the brain tissue in that area. There are four reasons why this might happen:
1. Thrombosis (obstruction of a blood vessel by a blood clot forming locally)
2. Embolism (obstruction due to an embolus from elsewhere in the body, see below),
3. Systemic hypoperfusion (general decrease in blood supply, e.g., in shock)
4. Venous thrombosis.
Stroke without an obvious explanation is termed "cryptogenic" (of unknown origin); this constitutes 30-40% of all ischemic strokes.
According to a review of 51 studies from 21 countries, the average incidence of subarachnoid hemorrhage is 9.1 per 100,000 annually. Studies from Japan and Finland show higher rates in those countries (22.7 and 19.7, respectively), for reasons that are not entirely understood. South and Central America, in contrast, have a rate of 4.2 per 100,000 on average.
Although the group of people at risk for SAH is younger than the population usually affected by stroke, the risk still increases with age. Young people are much less likely than middle-age people (risk ratio 0.1, or 10 percent) to have a subarachnoid hemorrhage. The risk continues to rise with age and is 60 percent higher in the very elderly (over 85) than in those between 45 and 55. Risk of SAH is about 25 percent higher in women over 55 compared to men the same age, probably reflecting the hormonal changes that result from the menopause, such as a decrease in estrogen levels.
Genetics may play a role in a person's disposition to SAH; risk is increased three- to fivefold in first-degree relatives of people having had a subarachnoid hemorrhage. However, lifestyle factors are more important in determining overall risk. These risk factors are smoking, hypertension (high blood pressure), and excessive alcohol consumption. Having smoked in the past confers a doubled risk of SAH compared to those who have never smoked. Some protection of uncertain significance is conferred by caucasian ethnicity, hormone replacement therapy, and diabetes mellitus. There is likely an inverse relationship between total serum cholesterol and the risk of non-traumatic SAH, though confirmation of this association is hindered by a lack of studies. Approximately 4 percent of aneurysmal bleeds occur after sexual intercourse and 10 percent of people with SAH are bending over or lifting heavy objects at the onset of their symptoms.
Overall, about 1 percent of all people have one or more cerebral aneurysms. Most of these, however, are small and unlikely to rupture.
Autosomal Dominant Retinal Vasculopathy with Cerebral Leukodystrophy (AD-RVCL) (previously known also as Cerebroretinal Vasculopathy, CRV, or Hereditary Vascular Retinopathy, HVR or Hereditary Endotheliopathy, Retinopathy, Nephropathy, and Stroke, HERNS) is an inherited condition resulting from a frameshift mutation to the TREX1 gene. This genetically inherited condition affects the retina and the white matter of the central nervous system, resulting in vision loss, lacunar strokes and ultimately dementia. Symptoms commonly begin in the early to mid-forties, and treatments currently aim to manage or alleviate the symptoms rather than treating the underlying cause. The overall prognosis is poor, and death can sometimes occur within 10 years of the first symptoms appearing.
AD-RVCL (CRV) Acronym
Autosomal Dominance (genetics) means only one copy of the gene is necessary for the symptoms to manifest themselves.
Retinal Vasculopathy means a disorder that is associated with a disease of the blood vessels in the retina.
Cerebral means having to do with the brain.
Leukodystrophy means a degeneration of the white matter of the brain.
Pathogenesis
The main pathologic process centers on small blood vessels that prematurely “drop out” and disappear. The retina of the eye and white matter of the brain are the most sensitive to this pathologic process. Over a five to ten-year period, this vasculopathy (blood vessel pathology) results in vision loss and destructive brain lesions with neurologic deficits and death.
Most recently, AD-RVCL (CRV) has been renamed. The new name is CHARIOT which stands for Cerebral Hereditary Angiopathy with vascular Retinopathy and Impaired Organ function caused by TREX1 mutations.
Treatment
Currently, there is no therapy to prevent the blood vessel deterioration.
About TREX1
The official name of the TREX1 gene is “three prime repair exonuclease 1.” The normal function of the TREX1 gene is to provide instructions for making the 3-prime repair exonuclease 1 enzyme. This enzyme is a DNA exonuclease, which means it trims molecules of DNA by removing DNA building blocks (nucleotides) from the ends of the molecules. In this way, it breaks down unneeded DNA molecules or fragments that may be generated during genetic material in preparation for cell division, DNA repair, cell death, and other processes.
Changes (mutations) to the TREX1 gene can result in a range of conditions one of which is AD-RVCL. The mutations to the TREX1 gene are believed to prevent the production of the 3-prime repair exonuclease 1 enzyme. Researchers suggest that the absence of this enzyme may result in an accumulation of unneeded DNA and RNA in cells. These DNA and RNA molecules may be mistaken by cells for those of viral invaders, triggering immune system reactions that result in the symptoms of AD-RVCL.
Mutations in the TREX1 gene have also been identified in people with other disorders involving the immune system. These disorders include a chronic inflammatory disease called systemic lupus erythematosus (SLE), including a rare form of SLE called chilblain lupus that mainly affects the skin.
The TREX1 gene is located on chromosome 3: base pairs 48,465,519 to 48,467,644
The immune system.
- The immune system is composed of white blood cells or leukocytes.
- There are 5 different types of leukocytes.
- Combined, the 5 different leukocytes represent the 2 types of immune systems (The general or innate immune system and the adaptive or acquired immune system).
- The adaptive immune system is composed of two types of cells (B-cells which release antibodies and T-cells which destroy abnormal and cancerous cells).
How the immune system becomes part of the condition.
During mitosis, tiny fragments of “scrap” single strand DNA naturally occur inside the cell. Enzymes find and destroy the “scrap” DNA. The TREX1 gene provides the information necessary to create the enzyme that destroys this single strand “scrap” DNA. A mutation in the TREX1 gene causes the enzyme that would destroy the single strand DNA to be less than completely effective. The less than completely effective nature of the enzyme allows “scrap” single strand DNA to build up in the cell. The buildup of “scrap” single strand DNA alerts the immune system that the cell is abnormal.
The abnormality of the cells with the high concentration of “scrap” DNA triggers a T-cell response and the abnormal cells are destroyed. Because the TREX1 gene is identical in all of the cells in the body the ineffective enzyme allows the accumulation of “scrap” single strand DNA in all of the cells in the body. Eventually, the immune system has destroyed enough of the cells in the walls of the blood vessels that the capillaries burst open. The capillary bursting happens throughout the body but is most recognizable when it happens in the eyes and brain because these are the two places where capillary bursting has the most pronounced effect.
Characteristics of AD-RVCL
- No recognizable symptoms until after age 40.
- No environmental toxins have been found to be attributable to the condition.
- The condition is primarily localized to the brain and eyes.
- Optically correctable, but continuous, deterioration of visual acuity due to extensive multifocal microvascular abnormalities and retinal neovascularization leading, ultimately, to a loss of vision.
- Elevated levels of alkaline phosphatase.
- Subtle vascular changes in the retina resembling telangiectasia (spider veins) in the parafovea circulation.
- Bilateral capillary occlusions involving the perifovea vessels as well as other isolated foci of occlusion in the posterior pole of the retina.
- Headaches due to papilledema.
- Mental confusion, loss of cognitive function, loss of memory, slowing of speech and hemiparesis due to “firm masses” and white, granular, firm lesions in the brain.
- Jacksonian seizures and grand mal seizure disorder.
- Progressive neurologic deterioration unresponsive to systemic corticosteroid therapy.
- Discrete, often confluent, foci of coagulation necrosis in the cerebral white matter with intermittent findings of fine calcium deposition within the necrotic foci.
- Vasculopathic changes involving both arteries and veins of medium and small caliber present in the cerebral white matter.
- Fibroid necrosis of vessel walls with extravasation of fibrinoid material into adjacent parenchyma present in both necrotic and non-necrotic tissue.
- Obliterative fibrosis in all the layers of many vessel walls.
- Parivascular, adventitial fibrosis with limited intimal thickening.
Conditions with similar symptoms that AD-RVCL can be misdiagnosed as:
- Brain tumors
- Diabetes
- Macular degeneration
- Telangiectasia (Spider veins)
- Hemiparesis (Stroke)
- Glaucoma
- Hypertension (high blood pressure)
- Systemic Lupus Erythematosus (SLE (same original pathogenic gene, but definitely a different disease because of a different mutation in TREX1))
- Polyarteritis nodosa
- Granulomatosis with polyangiitis
- Behçet's disease
- Lymphomatoid granulomatosis
- Vasculitis
Clinical Associations
- Raynaud's phenomenon
- Anemia
- Hypertension
- Normocytic anemia
- Normochromic anemia
- Gastrointestinal bleeding or telangiectasias
- Elevated alkaline phosphatase
Definitions
- Coagulation necrosis
- Endothelium
- Fibrinoid
- Fibrinoid necrosis
- Frameshift mutation
- Hemiparesis
- Jacksonian seizure
- Necrotic
- Necrosis
- Papilledema
- Perivascular
- Retinopathy
- Telangiectasia
- Vasculopathy
- Vascular
What AD-RVCL is not:
- Infection
- Cancer
- Diabetes
- Glaucoma
- Hypertension
- A neurological disorder
- Muscular dystrophy
- Systemic Lupus Erythematosis (SLE)
- Vasculitis
Things that have been tried but turned out to be ineffective or even make things worse:
- Antibiotics
- Steroids
- X-Ray therapy
- Immunosuppression
History of AD-RVCL (CRV)
- 1985 – 1988: CRV (Cerebral Retinal Vasculopathy) was discovered by John P. Atkinson, MD at Washington University School of Medicine in St. Louis, MO
- 1988: 10 families worldwide were identified as having CRV
- 1991: Related disease reported, HERNS (Hereditary Endiotheliopathy with Retinopathy, Nephropathy and Stroke – UCLA
- 1998: Related disease reported, HRV (Hereditary Retinal Vasculopathy) – Leiden University, Netherlands
- 2001: Localized to Chromosome 3.
- 2007: The specific genetic defect in all of these families was discovered in a single gene called TREX1
- 2008: Name changed to AD-RVCL Autosomal Dominant-Retinal Vasculopathy with Cerebral Leukodystrophy
- 2009: Testing for the disease available to persons 21 and older
- 2011: 20 families worldwide were identified as having CRV
- 2012: Obtained mouse models for further research and to test therapeutic agents
The risk of death from an intraparenchymal bleed in traumatic brain injury is especially high when the injury occurs in the brain stem. Intraparenchymal bleeds within the medulla oblongata are almost always fatal, because they cause damage to cranial nerve X, the vagus nerve, which plays an important role in blood circulation and breathing. This kind of hemorrhage can also occur in the cortex or subcortical areas, usually in the frontal or temporal lobes when due to head injury, and sometimes in the cerebellum.
For spontaneous ICH seen on CT scan, the death rate (mortality) is 34–50% by 30 days after the insult, and half of the deaths occur in the first 2 days. Even though the majority of deaths occurs in the first days after ICH, survivors have a long term excess mortality of 27% compared to the general population.
Diabetes mellitus increases the risk of stroke by 2 to 3 times. While intensive blood sugar control has been shown to reduce small blood vessel complications such as kidney damage and damage to the retina of the eye it has not been shown to reduce large blood vessel complications such as stroke.
Cerebral venous sinus thrombosis is more common in particular situations. 85% of patients have at least one of these risk factors:
- Thrombophilia, a tendency to develop blood clots due to abnormalities in coagulation, e.g. factor V Leiden, deficiency of protein C, protein S or antithrombin, or related problems
- Nephrotic syndrome, a kidney problem causing protein loss in the urine
- Chronic inflammatory diseases, such as inflammatory bowel disease, lupus and Behçet's disease
- Pregnancy and puerperium (the period after giving birth)
- Particular blood disorders, especially polycythemia vera and paroxysmal nocturnal hemoglobinuria
- Use of estrogen-containing forms of hormonal contraception
- Meningitis and infections of the ear, nose and throat area such as mastoiditis and sinusitis
- Direct injury to the venous sinuses
- Medical procedures in the head and neck area
- Sickle cell anemia
- Dehydration, primarily in infants and children
- Homocystinuria
Acquired cerebrovascular diseases are those that are obtained throughout a person's life that may be preventable by controlling risk factors. The incidence of cerebrovascular disease increases as an individual ages. Causes of acquired cerebrovascular disease include atherosclerosis, embolism, aneurysms, and arterial dissections. Atherosclerosis leads to narrowing of blood vessels and less perfusion to the brain, and it also increases the risk of thrombosis, or a blockage of an artery, within the brain. Major modifiable risk factors for atherosclerosis include:
Controlling these risk factors can reduce the incidence of atherosclerosis and stroke. Atrial fibrillation is also a major risk factor for strokes. Atrial fibrillation causes blood clots to form within the heart, which may travel to the arteries within the brain and cause an embolism. The embolism prevents blood flow to the brain, which leads to a stroke.
An aneurysm is an abnormal bulging of small sections of arteries, which increases the risk of artery rupture. Intracranial aneurysms are a leading cause of subarachnoid hemorrhage, or bleeding around the brain within the subarachnoid space. There are various hereditary disorders associated with intracranial aneurysms, such as Ehlers-Danlos syndrome, autosomal dominant polycystic kidney disease, and familial hyperaldosteronism type I. However, individuals without these disorders may also obtain aneurysms. The American Heart Association and American Stroke Association recommend controlling modifiable risk factors including smoking and hypertension.
Arterial dissections are tears of the internal lining of arteries, often associated with trauma. Dissections within the carotid arteries or vertebral arteries may compromise blood flow to the brain due to thrombosis, and dissections increase the risk of vessel rupture.
In 2004 the first adequately large scale study on the natural history and long-term prognosis of this condition was reported; this showed that at 16 months follow-up 57.1% of patients had full recovery, 29.5%/2.9%/2.2% had respectively minor/moderate/severe symptoms or impairments, and 8.3% had died. Severe impairment or death were more likely in those aged over 37 years, male, affected by coma, mental status disorder, intracerebral hemorrhage, thrombosis of the deep cerebral venous system, central nervous system infection and cancer. A subsequent systematic review of nineteen studies in 2006 showed that mortality is about 5.6% during hospitalisation and 9.4% in total, while of the survivors 88% make a total or near-total recovery. After several months, two thirds of the cases has resolution ("recanalisation") of the clot. The rate of recurrence was low (2.8%).
In children with CVST the risk of death is high. Poor outcome is more likely if a child with CVST develops seizures or has evidence of venous infarction on imaging.
Diseases associated with cerebral atherosclerosis include:
- Hypertensive arteriopathy
This pathological process involves the thickening and damage of arteriole walls. It mainly affects the ends of the arterioles which are located in the deep gray nuclei and deep white matter of the brain. It is thought that this is what causes cerebral microbleeds in deep brain regions. This small vessel damage can also reduce the clearance of amyloid-β, thereby increasing the likelihood of CAA.
Diseases cerebral atherosclerosis and associated diseases can cause are:
- Alzheimer's disease
Alzheimer's disease is a form of dementia that entails brain atrophy. Cerebral amyloid angiopathy is found in 90% of the cases at autopsy, with 25% being severe CAA.
- Cerebral microbleeds (CMB)
Cerebral microbleeds have been observed during recent studies on dementia sufferers using MRI.
- Stroke
Strokes occur from the sudden loss of blood flow to an area of the brain. The loss of flow is generally either from a blockage or hemorrhage. Studies of postmortem stroke cases have shown that intracranial athreosclerotic plaque build up occurred in over half of the individuals and over one third of the overall cases had stenotic build up.
No randomized, controlled clinical trial has established a survival benefit for treating patients (either with open surgery or radiosurgery) with AVMs that have not yet bled.
The prognosis for pediatric stroke survivors varies. The following are some common outcomes:
- Cerebral Palsy (often Hemiplegic Cerebral Palsy/Hemiplegia)
- Epilepsy
- Vision Loss
- Hearing Loss
High cholesterol levels have been inconsistently associated with (ischemic) stroke. Statins have been shown to reduce the risk of stroke by about 15%. Since earlier meta-analyses of other lipid-lowering drugs did not show a decreased risk, statins might exert their effect through mechanisms other than their lipid-lowering effects.
SAH is often associated with a poor outcome. The death rate (mortality) for SAH is between 40 and 50 percent, but trends for survival are improving. Of those that survive hospitalization, more than a quarter have significant restrictions in their lifestyle, and less than a fifth have no residual symptoms whatsoever. Delay in diagnosis of minor SAH (mistaking the sudden headache for migraine) contributes to poor outcome. Factors found on admission that are associated with poorer outcome include poorer neurological grade; systolic hypertension; a previous diagnosis of heart attack or SAH; liver disease; more blood and larger aneurysm on the initial CT scan; location of an aneurysm in the posterior circulation; and higher age. Factors that carry a worse prognosis during the hospital stay include occurrence of delayed ischemia resulting from vasospasm, development of intracerebral hematoma, or intraventricular hemorrhage (bleeding into the ventricles of the brain) and presence of fever on the eighth day of admission.
So-called "angiogram-negative subarachnoid hemorrhage", SAH that does not show an aneurysm with four-vessel angiography, carries a better prognosis than SAH with aneurysm; however, it is still associated with a risk of ischemia, rebleeding, and hydrocephalus. Perimesencephalic SAH (bleeding around the mesencephalon in the brain), however, has a very low rate of rebleeding or delayed ischemia, and the prognosis of this subtype is excellent.
The prognosis of head trauma is thought to be influenced in part by the location and amount of subarachnoid bleeding. It is difficult to isolate the effects of SAH from those of other aspects of traumatic brain injury; it is unknown whether the presence of subarachnoid blood actually worsens the prognosis or whether it is merely a sign that a significant trauma has occurred. People with moderate and severe traumatic brain injury who have SAH when admitted to a hospital have as much as twice the risk of dying as those who do not. They also have a higher risk of severe disability and persistent vegetative state, and traumatic SAH has been correlated with other markers of poor outcome such as post traumatic epilepsy, hydrocephalus, and longer stays in the intensive care unit. However, more than 90 percent of people with traumatic subarachnoid bleeding and a Glasgow Coma Score over 12 have a good outcome.
There is also modest evidence that genetic factors influence the prognosis in SAH. For example, having two copies of ApoE4 (a variant of the gene encoding apolipoprotein E that also plays a role in Alzheimer's disease) seems to increase risk for delayed ischemia and a worse outcome. The occurrence of hyperglycemia (high blood sugars) after an episode of SAH confers a higher risk of poor outcome.
The main risk is intracranial hemorrhage. This risk is difficult to quantify since many patients with asymptomatic AVMs will never come to medical attention. Small AVMs tend to bleed more often than do larger ones, the opposite of cerebral aneurysms. If a rupture or bleeding incident occurs, the blood may penetrate either into the brain tissue (cerebral hemorrhage) or into the subarachnoid space, which is located between the sheaths (meninges) surrounding the brain (subarachnoid hemorrhage). Bleeding may also extend into the ventricular system (intraventricular hemorrhage). Cerebral hemorrhage appears to be most common.
One long-term study (mean follow up greater than 20 years) of over 150 symptomatic AVMs (either presenting with bleeding or seizures) found the risk of cerebral hemorrhage to be approximately 4% per year, slightly higher than the 2-3% seen in other studies. A simple, rough approximation of a patient's lifetime bleeding risk is 105 - (patient age in years), assuming a 3% bleed risk annually. For example, a healthy 30-year-old patient would have approximately a 75% lifetime risk of at least one bleeding event. Ruptured AVMs are a significant source or morbidity and mortality; post rupture, as many as 29% of patients will die, and only 55% will be able to live independently.
Antenatal corticosteroids have a role in reducing incidence of germinal matrix hemorrhage in premature infants.
Factors increasing the risk of a subdural hematoma include very young or very old age. As the brain shrinks with age, the subdural space enlarges and the veins that traverse the space must travel over a wider distance, making them more vulnerable to tears. This and the fact that the elderly have more brittle veins make chronic subdural bleeds more common in older patients. Infants, too, have larger subdural spaces and are more predisposed to subdural bleeds than are young adults. For this reason, subdural hematoma is a common finding in shaken baby syndrome. In juveniles, an arachnoid cyst is a risk factor for a subdural hematoma.
Other risk factors for subdural bleeds include taking blood thinners (anticoagulants), long-term alcohol abuse, dementia, and the presence of a cerebrospinal fluid leak.
Patients with hypertensive encephalopathy who are promptly treated usually recover without deficit. However, if treatment is not administered, the condition can lead to death.