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In one study of 387 Behçet's disease (BD) patients that has been done for 20 years, 13% of men with BD developed to NBD and 5.6% of women developed to NBD.
Combining all statistical reports, approximately 9.4% (43 of 459) BD patients advanced to NBD. In addition, men were 2.8 times more likely to experience NBD than women. This fact indicates possible gender-based pathology.
In speaking about age of NBD patients, the general range was between 20 and 40. NBD patients with age less than 10 or more than 50 were very uncommon.
Because the cause of Behçet's disease is unknown, the cause responsible for neuro-Behçet's disease is unknown as well. Inflammation starts mainly due to immune system failure. However, no one knows what factors trigger the initiation of auto-immune disease like inflammation. Because the cause is unknown, it is impossible to eliminate or prevent the source that causes the disease. Therefore, treatments are focused on how to suppress the symptoms that hinders daily life activities.
"Primary" Central Nervous System (CNS) vasculitis is said to be present if there is no underlying cause. The exact mechanism of the primary disease is unknown, but the fundamental mechanism of all vasculitides is auto-immune. Other possible causes of cerebral vasculitis are infections, systemic auto-immune diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis, medications and drugs (amphetamine, cocaine and heroin), some forms of cancer (lymphomas, leukemia and lung cancer) and other forms of systemic vasculitis such as granulomatosis with polyangiitis, polyarteritis nodosa or Behçet's disease. It may imitate, and is in turn imitated by, a number of other diseases that affect the blood vessels of the brain diffusely such as fibromuscular dysplasia and thrombotic thrombocytopenic purpura.
Cerebral vasculitis or central nervous system vasculitis (sometimes the word angiitis is used instead of "vasculitis") is vasculitis (inflammation of the blood vessel wall) involving the brain and occasionally the spinal cord. It affects all of the vessels: very small blood vessels (capillaries), medium-size blood vessels (arterioles and venules), or large blood vessels (arteries and veins). If blood flow in a vessel with vasculitis is reduced or stopped, the parts of the body that receive blood from that vessel begins to die. It may produce a wide range of neurological symptoms, such as headache, skin rashes, feeling very tired, joint pains, difficulty moving or coordinating part of the body, changes in sensation, and alterations in perception, thought or behavior, as well as the phenomena of a mass lesion in the brain leading to coma and herniation. Some of its signs and symptoms may resemble multiple sclerosis. 10% have associated bleeding in the brain.
In Rasmussen’s encephalitis, there is chronic inflammation of the brain, with infiltration of T lymphocytes into the brain tissue. In most cases, this affects only one cerebral hemisphere, either the left or the right. This inflammation causes permanent damage to the cells of the brain, leading to atrophy of the hemisphere; the epilepsy that this causes may itself contribute to the brain damage. The epilepsy might derive from a disturbed GABA release, the main inhibitory neurotransmitter of the mammalian brain.
The cause of the inflammation is not known: infection by a virus has been suggested, but the evidence for this is inconclusive. In the 1990s it was suggested that auto-antibodies against the glutamate receptor GluR3 were important in causing the disease, but this is no longer thought to be the case. However, more recent studies report the presence of autoantibodies against the NMDA-type glutamate receptor subunit GluRepsilon2 (anti-NR2A antibodies) in a subset of patients with Rasmussen's encephalitis. There has also been some evidence that patients suffering from RE express auto-antibodies against alpha 7 subunit of the nicotinic acetylcholine receptor. By sequencing T cell receptors from various compartments it could be shown that RE patients present with peripheral CD8+ T-cell expansion which in some cases have been proven for years after disease onset.
Rasmussen's encephalitis has been recorded with a neurovisceral porphyria, acute intermittent porphyria and after ADEM (acute disseminated encephalomyelitis).
Chorioretinitis is often caused by toxoplasmosis and cytomegalovirus infections (mostly seen in immunodeficient subjects such as people with HIV or on immunosuppressant drugs). Congenital toxoplasmosis via transplacental transmission can also lead to sequelae such as chorioretinitis along with hydrocephalus and cerebral calcifications. Other possible causes of chorioretinitis are syphilis, sarcoidosis, tuberculosis, Behcet's disease, onchocerciasis, or West Nile virus. Chorioretinitis may also occur in presumed ocular histoplasmosis syndrome (POHS); despite its name, the relationship of POHS to "Histoplasma" is controversial.
Chorioretinitis is usually treated with a combination of corticosteroids and antibiotics. However, if there is an underlying cause such as HIV, specific therapy can be started as well.
A 2012 Cochrane Review found weak evidence suggesting that ivermectin could result in reduced chorioretinal lesions in patients with onchocercal eye disease. More research is needed to support this finding.
During the acute stage, treatment is aimed at reducing the inflammation. As in other inflammatory diseases, steroids may be used first of all, either as a short course of high-dose treatment, or in a lower dose for long-term treatment. Intravenous immunoglobulin is also effective both in the short term and in the long term, particularly in adults where it has been proposed as first-line treatment. Other similar treatments include plasmapheresis and tacrolimus, though there is less evidence for these. None of these treatments can prevent permanent disability from developing.
During the residual stage of the illness when there is no longer active inflammation, treatment is aimed at improving the remaining symptoms. Standard anti-epileptic drugs are usually ineffective in controlling seizures, and it may be necessary to surgically remove or disconnect the affected cerebral hemisphere, in an operation called hemispherectomy. This usually results in further weakness, hemianopsia and cognitive problems, but the other side of the brain may be able to take over some of the function, particularly in young children. The operation may not be advisable if the left hemisphere is affected, since this hemisphere contains most of the parts of the brain that control language. However, hemispherectomy is often very effective in reducing seizures.
Where an infectious agent or the inflammatory reaction to it destroys neurons and their axons, these include...
- Encephalitis, acute inflammation in the brain
- Neurosyphilis, an infection in the brain or spinal chord
- AIDS, disease of the immune system
Cerebral edema can result from brain trauma or from nontraumatic causes such as ischemic stroke, cancer, or brain inflammation due to meningitis or encephalitis.
Vasogenic edema caused by amyloid-modifying treatments, such as monoclonal antibodies, is known as ARIA-E (amyloid-related imaging abnormalities edema).
The blood–brain barrier (BBB) or the blood–cerebrospinal fluid (CSF) barrier may break down, allowing fluid to accumulate in the brain's extracellular space.
Altered metabolism may cause brain cells to retain water, and dilution of the blood plasma may cause excess water to move into brain cells.
Fast travel to high altitude without proper acclimatization can cause high-altitude cerebral edema (HACE).
Many different risk factors play a role in causing a neonatal stroke. Some maternal disorders that may contribute to neonatal strokes include: autoimmune disorders, coagulation disorders, prenatal cocaine exposure, infection, congenital heart disease, diabetes, and trauma. Placental disorders that increase the risk of stroke include placental thrombosis, placental abruption, placental infection, and chorioamnionitis. Other disorders that may increase the risk of a neonatal stroke are blood, homocysteine and lipid disorders, such as polycythemia, disseminated intravascular coagulopathy, prothrombin mutation, lipoprotein (a) deficiency, factor VIII deficiency (hemophilia A), and factor V Leiden mutation. Infectious disorders such as central nervous system (CNS) infection or systemic infection may also contribute.
Many infants who suffer a neonatal stroke also follow an uncomplicated pregnancy and delivery without identifiable risk factors, which exemplifies the necessity for further research on this subject.
Some evidence suggests that magnesium sulfate administered to mothers prior to early preterm birth reduces the risk of cerebral palsy in surviving neonates. Due to the risk of adverse effects treatments may have, it is unlikely that treatments to prevent neonatal strokes or other hypoxic events would be given routinely to pregnant women without evidence that their fetus was at extreme risk or has already suffered an injury or stroke. This approach might be more acceptable if the pharmacologic agents were endogenously occurring substances (those that occur naturally in an organism), such as creatine or melatonin, with no adverse side-effects.
Because of the period of high neuronal plasticity in the months after birth, it may be possible to improve the neuronal environment immediately after birth in neonates considered to be at risk of neonatal stroke. This may be done by enhancing the growth of axons and dendrites, synaptogenesis and myelination of axons with systemic injections of neurotrophins or growth factors which can cross the blood–brain barrier.
Unfortunately, cerebral atrophy is not usually preventable, however there are steps that can be taken to reduce the risks such as controlling your blood pressure, eating a healthy balanced diet including omega-3's and antioxidants, and staying active mentally, physically, and socially.
Cerebral edema is excess accumulation of fluid in the intracellular or extracellular spaces of the brain.
Those patients who survive initial hospitalization are likely to recover from Grinker's Myelinopathy, but may take up to a year or longer. Age seems to be a factor in the time for recovery, as one study indicated that the mean age of patients who recovered within one year was 10 years younger than that of patients who did not. For most patients, a recovery time of 3–6 months is typical. Even after recovering, however, some symptoms may persist, including cognitive deficits or Parkinsonian symptoms that can be treated separately.
The main cause of the neurological disorders is believed to be demyelination of the cerebral hemispheres, though there is currently no widely accepted consensus on why. The most commonly accepted theories for the cause of demyelination include hypoxia and cerebral edema due to carbon monoxide toxicity, drug overdose, or cerebral blood vessel damage, and a disruption of myelin-producing pathways.
Of the millions experiencing strokes worldwide, over 30,000 in the United States alone have developed some form of Dejerine–Roussy syndrome. 8% of all stroke patients will experience central pain syndrome, with 5% experiencing moderate to severe pain. The risk of developing Dejerine–Roussy syndrome is higher in older stroke patients, about 11% of stroke patients over the age of 80.
Middle cerebral artery syndrome is a condition whereby the blood supply from the middle cerebral artery (MCA) is restricted, leading to a reduction of the function of the portions of the brain supplied by that vessel: the lateral aspects of frontal, temporal and parietal lobes, the corona radiata, globus pallidus, caudate and putamen. The MCA is the most common site for the occurrence of ischemic stroke.
Depending upon the location and severity of the occlusion, signs and symptoms may vary within the population affected with MCA syndrome. More distal blockages tend to produce milder deficits due to more extensive branching of the artery and less ischemic response. In contrast, the most proximal occlusions result in widespread effects that can lead to significant cerebral edema, increased intracranial pressure, loss of consciousness and could even be fatal. In such occasions, mannitol (osmotic diuretic) or hypertonic saline are given to draw fluid out of the edematous cerebrum to minimise secondary injury. Hypertonic saline is better than mannitol, as mannitol being a diuretic will decrease the mean arterial pressure and since cerebral perfusion is mean arterial pressure minus intracranial pressure, mannitol will also cause a decrease in cerebral perfusion.
Contralateral hemiparesis and hemisensory loss of the face, upper and lower extremities is the most common presentation of MCA syndrome. Lower extremity function is more spared than that of the faciobrachial region. The majority of the primary motor and somatosensory cortices are supplied by the MCA and the cortical homunculus can, therefore, be used to localize the defects more precisely. Middle cerebral artery lesions mostly affect the dominant hemisphere i.e. the left cerebral hemisphere.
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.
Note: *faciobrachial deficits greater than that of the lower limb
Ischemia: A decreased or restriction of circulating blood flow to a region of the brain which deprives neurons of the necessary substrates (primarily glucose); represents 80% of all strokes. A thrombus or embolus plugs an artery so there is a reduction or cessation of blood flow. This hypoxia or anoxia leads to neuronal injury, which is known as a stroke. The death of neurons leads to a so-called softening of the cerebrum in the affected area.
Hemorrhage: Intracerebral hemorrhage occurs in deep penetrating vessels and disrupts the connecting pathways, causing a localized pressure injury and in turn injury to brain tissue in the affected area. Hemorrhaging can occur in instances of embolic ischemia, in which the previously obstructed region spontaneously restores blood flow. This is known as a hemorrhagic infarction and a resulting red infarct occurs, which points to a type of cerebral softening known as red softening.
Anterior cerebral artery syndrome is a condition whereby the blood supply from the anterior cerebral artery (ACA) is restricted, leading to a reduction of the function of the portions of the brain supplied by that vessel: the medial aspects of the frontal and parietal lobes, basal ganglia, anterior fornix and anterior corpus callosum.
Depending upon the area and severity of the occlusion, signs and symptoms may vary within the population affected with ACA syndrome. Blockages to the proximal (A1) segment of the vessel produce only minor deficits due to the collateral blood flow from the opposite hemisphere via the anterior communicating artery. Occlusions distal to this segment will result in more severe presentation of ACA syndrome. Contralateral hemiparesis and hemisensory loss of the lower extremity is the most common symptom associated with ACA syndrome.
In medicine, cerebral softening (encephalomalacia) is a localized softening of the brain substance, due to hemorrhage or inflammation. Three varieties, distinguished by their color and representing different stages of the morbid process, are known respectively as red, yellow, and white softening.
Studies have shown that PCA may be a variant of Alzheimer's disease (AD), with an emphasis on visual deficits. Although in primarily different, but sometimes overlapping, brain regions, both involve progressive neural degeneration, as shown by the loss of neurons and synapses, and the presence of neurofibrillary tangles and senile plaques in affected brain regions; this eventually leads to dementia in both diseases. PCA patients have more cortical damage and gray matter (cell body) loss in posterior regions, especially in the occipital, parietal, and temporal lobes, whereas Alzheimer’s patients typically experience more damage in the prefrontal cortex and hippocampus. PCA tends to impair working memory and anterograde memory, while leaving episodic memory intact, whereas AD patients typically have damaged episodic memory, suggesting some differences still lie in the primary areas of cortical damage.
Over time, however, atrophy in PCA patients may spread to regions commonly damaged in AD patients, leading to common AD symptoms such as deficits in memory, language, learning, and cognition. Although PCA has an earlier onset, many PCA patients have also been diagnosed with Alzheimer’s, suggesting that the degeneration has simply migrated anteriorly to other cortical brain regions.
There is no standard definition of PCA and no established diagnostic criteria, so it is not possible to know how many people have the condition. Some studies have found that about 5 percent of people diagnosed with Alzheimer’s disease have PCA. However, because PCA often goes unrecognized, the true percentage may be as high as 15 percent. Researchers and physicians are working to establish a standard definition and diagnostic criteria for PCA.
PCA may also be correlated with the diseases of Lewy body, Creutzfeldt–Jakob disease, Bálint's syndrome, and Gerstmann syndrome. In addition, PCA may result in part from mutations in the presenilin 1 gene (PSEN1).
Posterior cerebral artery syndrome is a condition whereby the blood supply from the posterior cerebral artery (PCA) is restricted, leading to a reduction of the function of the portions of the brain supplied by that vessel: the occipital lobe, the inferomedial temporal lobe, a large portion of the thalamus, and the upper brainstem and midbrain.
This event restricts the flow of blood to the brain in a near-immediate fashion. The blood hammer is analogous to the water hammer in hydrology and it consists of a sudden increase of the upstream blood pressure in a blood vessel when the bloodstream is abruptly blocked by vessel obstruction. Complete understanding of the relationship between mechanical parameters in vascular occlusions is a critical issue, which can play an important role in the future diagnosis, understanding and treatment of vascular diseases.
Depending upon the location and severity of the occlusion, signs and symptoms may vary within the population affected with PCA syndrome. Blockages of the proximal portion of the vessel produce only minor deficits due to the collateral blood flow from the opposite hemisphere via the posterior communicating artery. In contrast, distal occlusions result in more serious complications. Visual deficits, such as agnosia, prosopagnosia or cortical blindness (with bilateral infarcts) may be a product of ischemic damage to occipital lobe. Occlusions of the branches of the PCA that supply the thalamus can result in central post-stroke pain and lesions to the subthalamic branches can produce “a wide variety of deficits”.
Left posterior cerebral artery syndrome presents alexia without agraphia; the lesion is in the splenium of the corpus callosum.