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In last decade, similar to myocardial infarction treatment, thrombolytic drugs were introduced in the therapy of cerebral infarction. The use of intravenous rtPA therapy can be advocated in patients who arrive to stroke unit and can be fully evaluated within 3 h of the onset.
If cerebral infarction is caused by a thrombus occluding blood flow to an artery supplying the brain, definitive therapy is aimed at removing the blockage by breaking the clot down (thrombolysis), or by removing it mechanically (thrombectomy). The more rapidly blood flow is restored to the brain, the fewer brain cells die. In increasing numbers of primary stroke centers, pharmacologic thrombolysis with the drug tissue plasminogen activator (tPA), is used to dissolve the clot and unblock the artery.
Another intervention for acute cerebral ischaemia is removal of the offending thrombus directly. This is accomplished by inserting a catheter into the femoral artery, directing it into the cerebral circulation, and deploying a corkscrew-like device to ensnare the clot, which is then withdrawn from the body. Mechanical embolectomy devices have been demonstrated effective at restoring blood flow in patients who were unable to receive thrombolytic drugs or for whom the drugs were ineffective, though no differences have been found between newer and older versions of the devices. The devices have only been tested on patients treated with mechanical clot embolectomy within eight hours of the onset of symptoms.
Angioplasty and stenting have begun to be looked at as possible viable options in treatment of acute cerebral ischaemia. In a systematic review of six uncontrolled, single-center trials, involving a total of 300 patients, of intra-cranial stenting in symptomatic intracranial arterial stenosis, the rate of technical success (reduction to stenosis of <50%) ranged from 90-98%, and the rate of major peri-procedural complications ranged from 4-10%. The rates of restenosis and/or stroke following the treatment were also favorable. This data suggests that a large, randomized controlled trial is needed to more completely evaluate the possible therapeutic advantage of this treatment.
If studies show carotid stenosis, and the patient has residual function in the affected side, carotid endarterectomy (surgical removal of the stenosis) may decrease the risk of recurrence if performed rapidly after cerebral infarction. Carotid endarterectomy is also indicated to decrease the risk of cerebral infarction for symptomatic carotid stenosis (>70 to 80% reduction in diameter).
In tissue losses that are not immediately fatal, the best course of action is to make every effort to restore impairments through physical therapy, cognitive therapy, occupational therapy, speech therapy and exercise.
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.
The first-line treatment for arteritis is oral glucocorticoid (steroid) medication, such as prednisone, taken daily for a period of three months. After this initial phase, the medication may be reduced in dose or frequency, e.g. every other day, if possible. If the disease worsens with the new treatment schedule, a cytotoxic medication may be given, in addition to the glucocorticoid. Commonly used cytotoxic agents include azathioprine, methotrexate, or cyclophosphamide. The dose of glucocorticoid medication may be decreased if response to treatment is good. This medication may be reduced gradually once the disease becomes inactive, slowly tapering the dose (to allow the body time to adjust) until the medication may be stopped completely. Conversely, if the disease remains active, the medication will need to be increased. After six months, if the medication cannot be reduced in frequency to alternate days, or if in 12 months the medications cannot be stopped completely, then treatment is deemed to have failed.
Pulsed therapy is an alternative method of administering the medications above, using much higher doses over a short period of time (a pulse), to reduce the inflammation within the arteries. Methylprednisolone, a glucocorticoid, is often used for pulse therapy; cyclophosphamide is an alternative. This method has been shown to be successful for some patients. Immunosuppressive pulse therapy, such as with cyclophosphamide, has also demonstrated relief of symptoms associated with arteritis.
Corticosteroids, typically high-dose prednisone (1 mg/kg/day), must be started as soon as the diagnosis is suspected (even before the diagnosis is confirmed by biopsy) to prevent irreversible blindness secondary to ophthalmic artery occlusion. Steroids do not prevent the diagnosis from later being confirmed by biopsy, although certain changes in the histology may be observed towards the end of the first week of treatment and are more difficult to identify after a couple of months. The dose of prednisone is lowered after 2–4 weeks, and slowly tapered over 9–12 months. Tapering may require two or more years. Oral steroids are at least as effective as intravenous steroids, except in the treatment of acute visual loss where intravenous steroids appear to offer significant benefit over oral steroids. It is unclear if adding a small amount of aspirin is beneficial or not as it has not been studied.
Most people with Takayasu’s arteritis respond to steroids such as prednisone. The usual starting dose is approximately 1 milligram per kilogram of body weight per day (for most people, this is approximately 60 milligrams a day). Because of the significant side effects of long-term high-dose prednisone use, the starting dose is tapered over several weeks to a dose which controls symptoms while limiting the side effects of steroids.
Promising results are achieved with mycophenolate and tocilizumab. If treatment is not kept to a high standard, long-term damage or death can occur.
For patients who do not respond to steroids may require revascularization, either via vascular bypass or angioplasty and stenting. Outcomes following revascularization vary depending on the severity of the underlying disease
Aspirin reduces the overall risk of recurrence by 13% with greater benefit early on. Definitive therapy within the first few hours is aimed at removing the blockage by breaking the clot down (thrombolysis), or by removing it mechanically (thrombectomy). The philosophical premise underlying the importance of rapid stroke intervention was summed up as "Time is Brain!" in the early 1990s. Years later, that same idea, that rapid cerebral blood flow restoration results in fewer brain cells dying, has been proved and quantified.
Tight blood sugar control in the first few hours does not improve outcomes and may cause harm. High blood pressure is also not typically lowered as this has not been found to be helpful. Cerebrolysin, a mix of pig brain tissue used to treat acute ischemic stroke in many Asian and European countries, does not improve outcomes and may increase the risk of severe adverse events.
Keeping blood pressure below 140/90 mmHg is recommended. Anticoagulation can prevent recurrent ischemic strokes. Among people with nonvalvular atrial fibrillation, anticoagulation can reduce stroke by 60% while antiplatelet agents can reduce stroke by 20%. However, a recent meta-analysis suggests harm from anticoagulation started early after an embolic stroke. Stroke prevention treatment for atrial fibrillation is determined according to the CHA2DS2–VASc score. The most widely used anticoagulant to prevent thromboembolic stroke in patients with nonvalvular atrial fibrillation is the oral agent warfarin while a number of newer agents including dabigatran are alternatives which do not require prothrombin time monitoring.
Anticoagulants, when used following stroke, should not be stopped for dental procedures.
If studies show carotid artery stenosis, and the person has a degree of residual function on the affected side, carotid endarterectomy (surgical removal of the stenosis) may decrease the risk of recurrence if performed rapidly after stroke.
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.
Treatment depends on whether the aneurysm is ruptured and may involve a combination of antimicrobial drugs, surgery and/or endovascular treatment.
No definite standard treatment have been set. This is because treatments of the disease has been poorly studied as of 2014. Often in cases of inflammatory parenchymal disease, "corticosteroids should be given as infusions of
intravenous methylprednisolone followed by a slowly tapering course of oral steroids". It is suggested that therapy should be continued for a period of time even when the symptoms get suppressed because early relapse may occur. Sometimes, the medical doctors may suggest a different steroid depending on the nature of the disease, the severity, and the response to steroids. According to several studies, parenchymal NBD patients successfully suppress the symptoms with the prescribed steroids. As for non-parenchymal patients, there is no general consensus on how to treat the disease. The reason is that the mechanisms of cerebral venous thrombosis in BD are still poorly understood. Some doctors use anti-coagulants to prevent a clot. On the other hand, some doctors only give steroids and immunosuppressants alone.
AAION requires urgent and critical intervention with a very long course of corticosteroids to prevent further damage. While this treatment is in itself problematic, non-treatment leads to bilateral blindness and strokes.
There is much research currently underway looking at ways to protect the nerve (neuroprotection) or even regenerate new fibers within the optic nerve.
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.
There is no known cure for FMD. However, treatment focuses on relieving symptoms associated with it. Medical management is the most common form of treatment. The best approach to medically managing these patients is constantly being reevaluated as more information is learned about the disease.
Pediatric FMD medical and surgical treatments or interventions are available. Treatment is determined by factors such as age and disease location but routinely involve controlling hypertension, re-establishing vascular flow, clot prevention, and improving lifestyle such as diet, exercise and smoking cessation.
Medical therapy for pediatric population may involve the use of angiotensin-converting enzyme inhibitor (ACE inhibitors) and/or angiotensin II receptor blockers, multiple anti-hypertensive medications, diuretics, calcium channel blockers, and beta-blockers. Prevention of thrombosis of affected arteries may be taken through administration of an antiplatelet medication such as aspirin.
Percutaneous transluminal renal angioplasty (PTRA) remains the gold standard for renal-artery FMD. This treatment is useful when hypertension is difficult to control; patient is intolerant to the anti-hypertensive medications, non-complainant to medication regime and patient loss of renal volume due to ischemia. PTRA can also aide in preventing a lifelong dependency on a medication for such a young patient. According to Meyers, “effective PTRAs result in cured or controlled blood pressure, which is often signified by reductions in plasma renin activity and angiotensin II levels, and when compared with surgery, percutaneous balloon angioplasty is less costly, able to be performed on an outpatient basis, results in lower morbidity, and the use of stenting is not primarily necessary.” However, there is a subset of the pediatric population that are resistant to PTRA. Adverse events may include, “recurrent stenosis, arterial occlusion with renal loss, and arterial rupture with extravasations and pseudo aneurysm formation and may require surgical intervention.
Treatment is first with many different high-dose steroids, namely glucocorticoids. Then, if symptoms do not improve additional immunosuppression such as cyclophosphamide are added to decrease the immune system's attack on the body's own tissues. Cerebral vasculitis is a very rare condition that is difficult to diagnose, and as a result there are significant variations in the way it is diagnosed and treated.
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.
Treatments are generally directed toward stopping the inflammation and suppressing the immune system. Typically, corticosteroids such as prednisone are used. Additionally, other immune suppression drugs, such as cyclophosphamide and others, are considered. In case of an infection, antimicrobial agents including cephalexin may be prescribed. Affected organs (such as the heart or lungs) may require specific medical treatment intended to improve their function during the active phase of the disease.
Several treatments have been attempted for CRAS; however, none show definitive improvement in outcomes. The Undersea and Hyperbaric Medical Society lists Central Retinal Artery Occlusion (CRAO) as an approved indication for Hyperbaric Oxygen Therapy. This a treatment for CRAO that is covered by medical insurance in North America. Other treatments include ocular massage, anterior chamber paracentesis, and inhalation therapy of a mixture of 5% carbon dioxide and 95% oxygen.
Quick determination of the cause may lead to urgent measures to save the eye and life of the patient. High clinical suspicion should be kept for painless vision loss in patients with atherosclerosis, deep venous thrombosis, atrial fibrillation, pulmonary thromboembolism or other previous embolic episodes. Those caused by a carotid artery embolism or occlusion have the potential for further stroke by detachment of embolus and migration to an end-artery of the brain. Hence, proper steps to prevent such an eventuality need to be taken.
Retinal arterial occlusion is an ophthalmic emergency, and prompt treatment is essential. Completely anoxic retina in animal models causes irreversible damage in about 90 minutes. Nonspecific methods to increase blood flow and dislodge emboli include digital massage, 500 mg IV acetazolamide and 100 mg IV methylprednisolone (for possible arteritis). Additional measures include paracentesis of aqueous humor to decrease IOP acutely. An ESR should be drawn to detect possible giant cell arteritis. Improvement can be determined by visual acuity, visual field testing, and by ophthalmoscopic examination.
At a later stage, pan-retinal photocoagulation (PRP) with an argon laser appears effective in reducing the neovascular components and their sequelae.
The visual prognosis for ocular ischemic syndrome varies from usually poor to fair, depending on speed and effectiveness of the intervention. However, prompt diagnosis is crucial as the condition may be a presenting sign of serious cerebrovascular and ischemic heart diseases.
In 2009, the Undersea and Hyperbaric Medical Society added "central retinal artery occlusion" to their list of approved indications for hyperbaric oxygen (HBO). When used as an adjunctive therapy, the edema reducing properties of HBO, along with down regulation of inflammatory cytokines may contribute to the improvement in vision. Prevention of vision loss requires that certain conditions be met: the treatment be started before irreversible damage has occurred (over 24 hours), the occlusion must not also occur at the ophthalmic artery, and treatment must continue until the inner layers of the retina are again oxygenated by the retinal arteries.
Treatment approaches can include osmotherapy using mannitol, diuretics to decrease fluid volume, corticosteroids to suppress the immune system, hypertonic saline, and surgical decompression to allow the brain tissue room to swell without compressive injury.
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.
Treatment of aortitis depends on the underlying cause. Infectious causes commonly require antibiotic treatment, while those associated with autoimmune vasculitides are generally treated with steroids.
Management includes the following treatment priorities: stop the inflammation, treat complications, prevent and monitor for re-occurrence.
If a diagnosis of GCA is suspected, treatment with steroids should begin immediately. A sample (biopsy) of the temporal artery should be obtained to confirm the diagnosis and guide future management, but should not delay initiation of treatment. Treatment does not recover lost vision, but prevents further progression and second eye involvement. High dose corticosteroids may be tapered down to low doses over approximately one year.
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.
The artery can re-canalize over time and the edema can clear. However, optic atrophy leads to permanent loss of vision. Irreversible damage to neural tissue occurs after only 90 minutes. Two thirds of patients experience 20/400 vision while only one in six will experience 20/40 vision or better.