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Asymptomatic individuals with intracranial stenosis are typically told to take over the counter platelet inhibitors like aspirin whereas those with symptomatic presentation are prescribed anti-coagulation medications. For asymptomatic persons the idea is to stop the buildup of plaque from continuing. They are not experiencing symptoms; however if more build up occurs it is likely they will. For symptomatic individuals it is necessary to try and reduce the amount of stenosis. The anti-coagulation medications reduce the likelihood of further buildup while also trying to break down the current build up on the surface without an embolism forming. For those with severe stenosis that are at risk for impending stroke endovascular treatment is used. Depending on the individual and the location of the stenosis there are multiple treatments that can be undertaken. These include angioplasty, stent insertion, or bypass the blocked area.
Various studies have investigated the use of anticoagulation to suppress blood clot formation in cerebral venous sinus thrombosis. Before these trials had been conducted, there had been a concern that small areas of hemorrhage in the brain would bleed further as a result of treatment; the studies showed that this concern was unfounded. Clinical practice guidelines now recommend heparin or low molecular weight heparin in the initial treatment, followed by warfarin, provided there are no other bleeding risks that would make these treatments unsuitable. Some experts discourage the use of anticoagulation if there is extensive hemorrhage; in that case, they recommend repeating the imaging after 7–10 days. If the hemorrhage has decreased in size, anticoagulants are started, while no anticoagulants are given if there is no reduction.
The duration of warfarin treatment depends on the circumstances and underlying causes of the condition. If the thrombosis developed under temporary circumstances (e.g. pregnancy), three months are regarded as sufficient. If the condition was unprovoked but there are no clear causes or a "mild" form of thrombophilia, 6 to 12 months is advised. If there is a severe underlying thrombosis disorder, warfarin treatment may need to continue indefinitely.
Thrombolysis (removal of the blood clot with "clot buster" medication) has been described, either systemically by injection into a vein or directly into the clot during angiography. The 2006 European Federation of Neurological Societies guideline recommends that thrombolysis is only used in patients who deteriorate despite adequate treatment, and other causes of deterioration have been eliminated. It is unclear which drug and which mode of administration is the most effective. Bleeding into the brain and in other sites of the body is a major concern in the use of thrombolysis. American guidelines make no recommendation with regards to thrombolysis, stating that more research is needed.
Raised intracranial pressure, if severe or threatening vision, may require therapeutic lumbar puncture (removal of excessive cerebrospinal fluid), medication (acetazolamide), or neurosurgical treatment (optic nerve sheath fenestration or shunting). In certain situations, anticonvulsants may be used to try to prevent seizures. These situations include focal neurological problems (e.g. inability to move a limb) and focal changes of the brain tissue on CT or MRI scan. Evidence to support or refute the use of antiepileptic drugs as a preventive measure, however, is lacking.
Management involves general measures to stabilize the person while also using specific investigations and treatments. These include the prevention of rebleeding by obliterating the bleeding source, prevention of a phenomenon known as vasospasm, and prevention and treatment of complications.
Stabilizing the person is the first priority. Those with a depressed level of consciousness may need to be intubated and mechanically ventilated. Blood pressure, pulse, respiratory rate, and Glasgow Coma Scale are monitored frequently. Once the diagnosis is confirmed, admission to an intensive care unit may be preferable, especially since 15 percent may have further bleeding soon after admission. Nutrition is an early priority, with by mouth or nasogastric tube feeding being preferable over parenteral routes. In general, pain control is restricted to less-sedating agents such as codeine, as sedation may impact on the mental status and thus interfere with the ability to monitor the level of consciousness. Deep vein thrombosis is prevented with compression stockings, intermittent pneumatic compression of the calves, or both. A bladder catheter is usually inserted to monitor fluid balance. Benzodiazepines may be administered to help relieve distress. Antiemetic drugs should be given to awake persons.
People with poor clinical grade on admission, acute neurologic deterioration, or progressive enlargement of ventricles on CT scan are, in general, indications for the placement of an external ventricular drain by a neurosurgeon. The external ventricular drain may be inserted at the bedside or in the operating room. In either case, strict aseptic technique must be maintained during insertion. In people with aneurysmal subarachnoid hemorrhage the EVD is used to remove cerebrospinal fluid, blood, and blood byproducts that increase intracranial pressure and may increase the risk for cerebral vasospasm.
Vasospasm, in which the blood vessels constrict and thus restrict blood flow, is a serious complication of SAH. It can cause ischemic brain injury (referred to as "delayed ischemia") and permanent brain damage due to lack of oxygen in parts of the brain. It can be fatal if severe. Delayed ischemia is characterized by new neurological symptoms, and can be confirmed by transcranial doppler or cerebral angiography. About one third of people admitted with subarachnoid hemorrhage will have delayed ischemia, and half of those have permanent damage as a result. It is possible to screen for the development of vasospasm with transcranial Doppler every 24–48 hours. A blood flow velocity of more than 120 centimeters per second is suggestive of vasospasm.
The use of calcium channel blockers, thought to be able to prevent the spasm of blood vessels by preventing calcium from entering smooth muscle cells, has been proposed for prevention. The calcium channel blocker nimodipine when taken by mouth improves outcome if given between the fourth and twenty-first day after the bleeding, even if it does not reduce the amount of vasospasm detected on angiography. It is the only Food and Drug Administration (FDA) approved drug for treating cerebral vasospasm. In "traumatic" subarachnoid hemorrhage, nimodipine does not affect long-term outcome, and is not recommended. Other calcium channel blockers and magnesium sulfate have been studied, but are not presently recommended; neither is there any evidence that shows benefit if nimodipine is given intravenously.
Some older studies have suggested that statin therapy might reduce vasospasm, but a subsequent meta-analysis including further trials did not demonstrate benefit on either vasospasm or outcomes. While corticosteroids with mineralocorticoid activity may help prevent vasospasm their use does not appear to change outcomes.
A protocol referred to as "triple H" is often used as a measure to treat vasospasm when it causes symptoms; this is the use of intravenous fluids to achieve a state of hypertension (high blood pressure), hypervolemia (excess fluid in the circulation), and hemodilution (mild dilution of the blood). Evidence for this approach is inconclusive; no randomized controlled trials have been undertaken to demonstrate its effect.
If the symptoms of delayed ischemia do not improve with medical treatment, angiography may be attempted to identify the sites of vasospasms and administer vasodilator medication (drugs that relax the blood vessel wall) directly into the artery. Angioplasty (opening the constricted area with a balloon) may also be performed.
Splenic infarction can be induced for the treatment of such conditions as portal hypertension or splenic injury. It can also be used prior to splenectomy for the prevention of blood loss.
Treatment of a subdural hematoma depends on its size and rate of growth. Some small subdural hematomas can be managed by careful monitoring until the body heals itself. Other small subdural hematomas can be managed by inserting a temporary small catheter through a hole drilled through the skull and sucking out the hematoma; this procedure can be done at the bedside. Large or symptomatic hematomas require a craniotomy, the surgical opening of the skull. A surgeon then opens the dura, removes the blood clot with suction or irrigation, and identifies and controls sites of bleeding. Postoperative complications include increased intracranial pressure, brain edema, new or recurrent bleeding, infection, and seizure. The injured vessels must be repaired.
Depending on the size and deterioration, age of the patient, and anaesthetic risk posed, subdural hematomas occasionally require craniotomy for evacuation; most frequently, simple burr holes for drainage; often conservative treatment; and rarely, palliative treatment in patients of extreme age or with no chance of recovery.
In those with a chronic subdural hematoma, but without a history of seizures, the evidence is unclear if using anticonvulsants is harmful or beneficial.
Treatment focuses on monitoring and should be accomplished with inpatient floor service for individuals responsive to commands or neurological ICU observation for those with impaired levels of consciousness. Extra attention should be placed on intracranial pressure (ICP) monitoring via an intraventricular catheter and medications to maintain ICP, blood pressure, and coagulation. In more severe cases an external ventricular drain may be required to maintain ICP and evacuate the hemorrhage, and in extreme cases an open craniotomy may be required. In cases of unilateral IVH with small intraparenchymal hemorrhage the combined method of stereotaxy and open craniotomy has produced promising results.
Emergency treatment for individuals with a ruptured cerebral aneurysm generally includes restoring deteriorating respiration and reducing intracranial pressure. Currently there are two treatment options for securing intracranial aneurysms: surgical clipping or endovascular coiling. If possible, either surgical clipping or endovascular coiling is usually performed within the first 24 hours after bleeding to occlude the ruptured aneurysm and reduce the risk of rebleeding.
While a large meta-analysis found the outcomes and risks of surgical clipping and endovascular coiling to be statistically similar, no consensus has been reached. In particular, the large randomised control trial International Subarachnoid Aneurysm Trial appears to indicate a higher rate of recurrence when intracerebral aneurysms are treated using endovascular coiling. Analysis of data from this trial has indicated a 7% lower eight-year mortality rate with coiling, a high rate of aneurysm recurrence in aneurysms treated with coiling—from 28.6-33.6% within a year, a 6.9 times greater rate of late retreatment for coiled aneurysms, and a rate of rebleeding 8 times higher than surgically-clipped aneurysms.
Treatment depends on whether the aneurysm is ruptured and may involve a combination of antimicrobial drugs, surgery and/or endovascular treatment.
The best-studied medical treatment for intracranial hypertension is acetazolamide (Diamox), which acts by inhibiting the enzyme carbonic anhydrase, and it reduces CSF production by six to 57 percent. It can cause the symptoms of hypokalemia (low blood potassium levels), which include muscle weakness and tingling in the fingers. Acetazolamide cannot be used in pregnancy, since it has been shown to cause embryonic abnormalities in animal studies. Also, in human beings it has been shown to cause metabolic acidosis as well as disruptions in the blood electrolyte levels of newborn babies. The diuretic furosemide is sometimes used for a treatment if acetazolamide is not tolerated, but this drug sometimes has little effect on the ICP.
Various analgesics (painkillers) may be used in controlling the headaches of intracranial hypertension. In addition to conventional agents such as paracetamol, a low dose of the antidepressant amitriptyline or the anticonvulsant topiramate have shown some additional benefit for pain relief.
The use of steroids in the attempt to reduce the ICP is controversial. These may be used in severe papilledema, but otherwise their use is discouraged.
Aneurysms can be treated by clipping the base of the aneurysm with a specially-designed clip. Whilst this is typically carried out by craniotomy, a new endoscopic endonasal approach is being trialled. Surgical clipping was introduced by Walter Dandy of the Johns Hopkins Hospital in 1937
After clipping, a catheter angiogram or CTA can be performed to confirm complete clipping.
Initial measures can include rest, caffeine intake (via coffee or intravenous infusion), and hydration. Corticosteroids may provide transient relief for some patients. An abdominal binder — a type of garment that increases intracranial pressure by compressing the abdomen — can temporarily relieve symptoms for some people.
Since cerebral swelling presents a danger to the patient, treatment of cerebral contusion aims to prevent swelling. Measures to avoid swelling include prevention of hypotension (low blood pressure), hyponatremia (insufficient sodium), and hypercapnia (increased carbon dioxide in the blood). Due to the danger of increased intracranial pressure, surgery may be necessary to reduce it. People with cerebral contusion may require intensive care and close monitoring.
The treatment of choice for this condition is the surgical application of epidural blood patches, which has a higher success rate than conservative treatments of bed rest and hydration. Through the injection of a person's own blood into the area of the hole in the dura, an epidural blood patch uses blood's clotting factors to clot the sites of holes. The volume of autologous blood and number of patch attempts for patients is highly variable. One-quarter to one-third of SCSFLS patients do not have relief of symptoms from epidural blood patching.
Nitroglycerin can be used immediately to widen the coronary arteries and help increase blood flow to the heart. In addition, nitroglycerin causes peripheral venous and artery dilation reducing cardiac preload and afterload. These reductions allow for decreased stress on the heart and therefore lower the oxygen demand of the heart's muscle cells.
Antiplatelet drugs such as aspirin and clopidogrel can help reduce the progression of atherosclerotic plaque formation, as well as combining these with an anticoagulant such as a low molecular weight heparin.
The first step in symptom control is drainage of cerebrospinal fluid by lumbar puncture. If necessary, this may be performed at the same time as a diagnostic LP (such as done in search of a CSF infection). In some cases, this is sufficient to control the symptoms, and no further treatment is needed.
The procedure can be repeated if necessary, but this is generally taken as a clue that additional treatments may be required to control the symptoms and preserve vision. Repeated lumbar punctures are regarded as unpleasant by patients, and they present a danger of introducing spinal infections if done too often. Repeated lumbar punctures are sometimes needed to control the ICP urgently if the patient's vision deteriorates rapidly.
As of 2014, no treatment strategy has yet been investigated in a randomized clinical trial. Verapamil, nimodipine, and other calcium channel blockers may help reduce the intensity and frequency of the headaches. A clinician may recommend rest and the avoidance of activities or vasoactive drugs which trigger symptoms (see § Causes). Analgesics and anticonvulsants can help manage pain and seizures, respectively.
Prinzmetal's angina typically responds to nitrates and calcium channel blockers.
Use of a beta blocker such as propranolol is contraindicated in Prinzmetal's angina. Prazosin has also been found to be of value in some patients. Coronary revascularization is only useful when the patient shows concomitant coronary atherosclerosis on coronary angiogram.
As with other types of intracranial hematomas, the blood may be removed surgically to remove the mass and reduce the pressure it puts on the brain. The hematoma is evacuated through a burr hole or craniotomy. If transfer to a facility with neurosurgery is prolonged trephination may be performed in the emergency department.
The treatment includes lowering the increased intracranial pressure and starting intravenous antibiotics (and meanwhile identifying the causative organism mainly by blood culture studies).
Hyperbaric oxygen therapy (HBO2 or HBOT) is indicated as a primary and adjunct treatment which provides four primary functions.
Firstly, HBOT reduces intracranial pressure. Secondly, high partial pressures of oxygen act as a bactericide and thus inhibits the anaerobic and functionally anaerobic flora common in brain abscess. Third, HBOT optimizes the immune function thus enhancing the host defense mechanisms and fourth, HBOT has been found to be of benefit when brain abscess is concomitant with cranial osteomyleitis.
Secondary functions of HBOT include increased stem cell production and up-regulation of VEGF which aid in the healing and recovery process.
Surgical drainage of the abscess remains part of the standard management of bacterial brain abscesses. The location and treatment of the primary lesion also crucial, as is the removal of any foreign material (bone, dirt, bullets, and so forth).
There are few exceptions to this rule: "Haemophilus influenzae" meningitis is often associated with subdural effusions that are mistaken for subdural empyemas. These effusions resolve with antibiotics and require no surgical treatment. Tuberculosis can produce brain abscesses that look identical to conventional bacterial abscesses on CT imaging. Surgical drainage or aspiration is often necessary to identify "Mycobacterium tuberculosis", but once the diagnosis is made no further surgical intervention is necessary.
CT guided stereotactic aspiration is also indicated in the treatment of brain abscess.
Restoring adequate blood flow to the heart muscle in people with heart failure and significant coronary artery disease is strongly associated with improved survival, some research showing up to 75% survival rates over 5 years. A stem cell study indicated that using autologous cardiac stem cells as a regenerative approach for the human heart (after a heart attack) has great potential.
American Heart Association practice guidelines indicate (ICD) implantable cardioverter-defibrillator use in those with ischemic cardiomyopathy (40 days post-MI) that are (NYHA) New York Heart Association functional class I. LVEF of >30% is often used to differentiate primary from ischemic cardiomyopathy, and a prognostic indicator. At the same time, people who undergo ventricular restoration on top of coronary artery bypass show improved postoperative ejection fraction as compared to those treated with only coronary artery bypass surgery. Severe cases are treated with heart transplantation.
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.
One of the most important features differentiating ischemic cardiomyopathy from the other forms of cardiomyopathy is the shortened, or worsened all-cause mortality in patients with ischemic cardiomyopathy. According to several studies, coronary artery bypass graft surgery has a survival advantage over medical therapy (for ischemic cardiomyopathy) across varied follow-ups.
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.
If the diagnostic workup reveals a systemic disease process, directed therapies to treat that underlying cause should be initiated. If the amaurosis fugax is caused by an atherosclerotic lesion, aspirin is indicated, and a carotid endarterectomy considered based on the location and grade of the stenosis. Generally, if the carotid artery is still patent, the greater the stenosis, the greater the indication for endarterectomy. "Amaurosis fugax appears to be a particularly favorable indication for carotid endarterectomy. Left untreated, this event carries a high risk of stroke; after carotid endarterectomy, which has a low operative risk, there is a very low postoperative stroke rate." However, the rate of subsequent stroke after amaurosis is significantly less than after a hemispheric TIA, therefore there remains debate as to the precise indications for which a carotid endarterectomy should be performed. If the full diagnostic workup is completely normal, patient observation is recommended.