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Treatment depends on the location and size of the AVM and whether there is bleeding or not.
The treatment in the case of sudden bleeding is focused on restoration of vital function. Anticonvulsant medications such as phenytoin are often used to control seizure; medications or procedures may be employed to relieve intracranial pressure. Eventually, curative treatment may be required to prevent recurrent hemorrhage. However, any type of intervention may also carry a risk of creating a neurological deficit.
Preventive treatment of as yet unruptured brain AVMs has been controversial, as several studies suggested favorable long-term outcome for unruptured AVM patients not undergoing intervention. The NIH-funded longitudinal ARUBA study ("A Randomized trial of Unruptured Brain AVMs) compares the risk of stroke and death in patients with preventive AVM eradication versus those followed without intervention. Interim results suggest that fewer strokes occur as long as patients with unruptured AVM do not undergo intervention. Because of the higher than expected event rate in the interventional arm of the ARUBA study, NIH/NINDS stopped patient enrollment in April 2013, while continuing to follow all participants to determine whether the difference in stroke and death in the two arms changes over time.
Surgical elimination of the blood vessels involved is the preferred curative treatment for many types of AVM. Surgery is performed by a neurosurgeon who temporarily removes part of the skull (craniotomy), separates the AVM from surrounding brain tissue, and resects the abnormal vessels. While surgery can result in an immediate, complete removal of the AVM, risks exist depending on the size and the location of the malformation. The AVM must be resected en bloc, for partial resection will likely cause severe hemorrhage. The preferred treatment of Spetzler-Martin grade 1 and 2 AVMs in young, healthy patients is surgical resection due to the relatively small risk of neurological damage compared to the high lifetime risk of hemorrhage. Grade 3 AVMs may or may not be amenable to surgery. Grade 4 and 5 AVMs are not usually surgically treated.
Radiosurgery has been widely used on small AVMs with considerable success. The Gamma Knife is an apparatus used to precisely apply a controlled radiation dosage to the volume of the brain occupied by the AVM. While this treatment does not require an incision and craniotomy (with their own inherent risks), three or more years may pass before the complete effects are known, during which time patients are at risk of bleeding. Complete obliteration of the AVM may or may not occur after several years, and repeat treatment may be needed. Radiosurgery is itself not without risk. In one large study, nine percent of patients had transient neurological symptoms, including headache, after radiosurgery for AVM. However, most symptoms resolved, and the long-term rate of neurological symptoms was 3.8%.
Embolization is performed by interventional neuroradiologists and the occlusion of blood vessels most commonly is obtained with Ethylene-vinyl alcohol copolymer (Onyx) or N-butyl cyanoacrylate (NBCA). These substances are introduced by a radiographically guided catheter, and block vessels responsible for blood flow into the AVM. Embolization is frequently used as an adjunct to either surgery or radiation treatment. Embolization reduces the size of the AVM and during surgery it reduces the risk of bleeding. However, embolization alone may completely obliterate some AVMs. In high flow intranidal fistulas balloons can also be used to reduce the flow so that embolization can be done safely.
Treatment for brain AVMs can be symptomatic, and patients should be followed by a neurologist for any seizures, headaches, or focal neurologic deficits. AVM-specific treatment may also involve endovascular embolization, neurosurgery or radiosurgery.
Embolization, that is, cutting off the blood supply to the AVM with coils, particles, acrylates, or polymers introduced by a radiographically guided catheter, may be used in addition to neurosurgery or radiosurgery, but is rarely successful in isolation except in smaller AVMs. Gamma knife may also be used.
Intracerebral hemorrhages is a severe condition requiring prompt medical attention. Treatment goals include lifesaving interventions, supportive measures, and control of symptoms. Treatment depends on the location, extent, and cause of the bleeding. Often, treatment can reverse the damage that has been done.
A craniotomy is sometimes done to remove blood, abnormal blood vessels, or a tumor. Medications may be used to reduce swelling, prevent seizures, lower blood pressure, and control pain.
One approach used for treatment is embolization. A six-vessel angiogram is employed to determine the vascular supply to the fistula. Detachable coils, liquid embolic agents like NBCA, and onyx, or combinations of both are injected into the blood vessel to occlude the DAVF. Preoperative embolization can also be used to supplement surgery.
DAVFs are also managed surgically. The operative approach varies depending on the location of the lesion.
Stereotactic radiosurgery
Stereotactic radiosurgery is used obliterating DAVFs post-embolization, and is considered an important adjunct. Use of this method, however, is limited to benign DAVFs that have failed other treatments.
Treatment depends substantially of the type of ICH. Rapid CT scan and other diagnostic measures are used to determine proper treatment, which may include both medication and surgery.
- Tracheal intubation is indicated in people with decreased level of consciousness or other risk of airway obstruction.
- IV fluids are given to maintain fluid balance, using isotonic rather than hypotonic fluids.
The mainstay of treatment for CCF is endovascular therapy. This may be transarterial (mostly in the case of direct CCF) or transvenous (most commonly in indirect CCF). Occasionally, more direct approaches, such as direct transorbital puncture of the cavernous sinus or cannulation of the draining superior orbital vein are used when conventional approaches are not possible. Spontaneous resolution of indirect fistulae has been reported but is uncommon. Staged manual compression of the ipsilateral carotid has been reported to assist with spontaneous closure in selected cases.
Direct CCF may be treated by occlusion of the affected cavernous sinus (coils, balloon, liquid agents), or by reconstruction of the damaged internal carotid artery (stent, coils or liquid agents).
Indirect CCF may be treated by occlusion of the affected cavernous sinus with coils, liquid agents or a combination of both.
Head circumference measurements should be obtained regularly and monitored carefully to detect hydrocephalus. Neurosurgical procedures to relieve hydrocephalus are important. A ventriculoperitoneal shunt may be required in some infants. A pediatric cardiologist should be consulted to manage high-output failure, if present. Often patients need to be intubated. In most cases, the fistulous arteries feeding into the Vein of Galen must be blocked, thereby reducing the blood flow into the vein. Open surgery has a high morbidity and mortality. Recent advances over the past few decades have made endovascular embolization the preferred method of treatment. These treatments are preferred because they offer little threat to the surrounding brain tissue. However, there have been several reported cases of arteriovenous malformations recurring. The young age of many patients, the complex vascular anatomy, and the sensitive location of the Vein of Galen offer considerable challenges to surgeons. Another treatment option is Radiotherapy. Radiotherapy, also called radiosurgery, involves the use of focused beams to damage the blood vessel. Radiotherapy is often not pursued as a treatment because the effects of the procedure can take months or years and there is risk of damaging adjacent brain tissue.
Surgery is required if the hematoma is greater than , if there is a structural vascular lesion or lobar hemorrhage in a young patient.
- A catheter may be passed into the brain vasculature to close off or dilate blood vessels, avoiding invasive surgical procedures.
- Aspiration by stereotactic surgery or endoscopic drainage may be used in basal ganglia hemorrhages, although successful reports are limited.
Surgery is not always an option when the anatomy of the malformation creates too much of a risk. Recent improvements in endovascular procedures have made many cases, which were not surgically accessible, treatable. Endovascular treatments involve delivering drugs, balloons, or coils to the site of the malformation through blood vessels via catheters. These treatments work by limiting blood flow through the vein. There is, however, still risk of complications from endovascular treatments. The wall of the vein can be damaged during the procedure and, in some cases, the emboli can become dislodged and travel through the vascular system. Two-dimensional echocardiography with color-flow imaging and pulsed Doppler ultrasound was used to evaluate one fetus and five neonates with a Vein of Galen malformation. Color-flow imaging and pulsed Doppler ultrasonography provided anatomical and pathophysiological information regarding cardiac hemodynamics and intracranial blood flow; with the patient's clinical status, these methods provided a reliable, noninvasive means to evaluate the effectiveness of therapy and the need for further treatment in neonates with Vein of Galen malformations. When none of these procedures are viable, shunting can be used to ameliorate the pressure inside the varix. Seizures usually are managed with antiepileptic medications.
Benign tumors may not require treatment but may need to be monitored for any change in the growth. Growth of the tumors in the nose, lips, or eyelids can be treated with steroid drugs to slow its progress. Steroids can be taken orally or injected directly into the tumor. Applying pressure to the tumor can also be used to minimize swelling at the site of the hemangioma. A procedure that uses small particles to close off the blood supply is known as sclerotherapy. This allows for tumor shrinkage and less pain. It is possible for the tumor to regrow its blood supply after the procedure has been done. If the lesion caused by the cavernous hemangioma is destroying healthy tissue around it or if the patient is experiencing major symptoms, then surgery can be used to remove the tumor piecemeal. A common complication of the surgery is hemorrhage and the loss of blood. There is also the possibility of the hemangioma reoccurring after its removal. Additionally, the risk of a stroke or death is also possible.
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.
In the treatment of a brain cavernous hemangioma, neurosurgery is usually the treatment chosen. Research needs to be conducted on the efficacy of treatment with stereotactic radiation therapy, especially on the long-term. However, radiotherapy is still being studied as a form of treatment if neurosurgery is too dangerous due the location of the cavernoma. Genetic researchers are still working on determining the cause of the illness and the mechanism behind blood vessel formation. Clinical trials are being conducted to better assess when it is appropriate to treat a patient with this malformation and with what treatment method. Additionally, long term studies are being conducted because there is no information related to the long-term outlook of patients with cavernoma. A registry exists known as The International Cavernous Angioma Patient Registry collects information from patients diagnosed with cavernoma in order to facilitate discovery of non-invasive treatments.
The natural history of this disorder is not well known. The long term outlook for patients with treated moyamoya seems to be good. While symptoms may seem to improve almost immediately after the in-direct EDAS, EMS, and multiple burr holes surgeries, it will take probably 6–12 months before new vessels can develop to give a sufficient blood supply. With the direct STA-MCA surgery, increased blood supply is immediate.
Once major stroke or bleeding take place, even with treatment, the patient may be left with permanent loss of function so it is very important to treat this condition promptly.
Dr. Michael Scott, MD discusses the success rate for Moyamoya surgery in
Historically, the treatment of arterial aneurysms has been limited to either surgical intervention, or watchful waiting in combination with control of blood pressure. In recent years, endovascular or minimally invasive techniques have been developed for many types of aneurysms. Aneurysm Clips are used for surgical procedure i.e. clipping of aneurysms.
An acute nosebleed may be managed with a variety of measures, such as packing of the nasal cavity with absorbent swabs or gels. Removal of the packs after the bleeding may lead to reopening of the fragile vessels, and therefore lubricated or atraumatic packing is recommended. Some patients may wish to learn packing themselves to deal with nosebleeds without having to resort to medical help.
Frequent nosebleeds can be prevented in part by keeping the nostrils moist, and by applying saline solution, estrogen-containing creams or tranexamic acid; these have few side effects and may have a small degree of benefit. A number of additional modalities has been used to prevent recurrent bleeding if simple measures are unsuccessful. Medical therapies include oral tranexamic acid and estrogen; the evidence for these is relatively limited, and estrogen is poorly tolerated by men and possibly carries risks of cancer and heart disease in women past the menopause. Nasal coagulation and cauterization may reduce the bleeding from telangiectasias, and is recommended before surgery is considered. However, it is highly recommended to use the least heat and time to prevent septal perforations and excessive trauma to the nasal mucosa that are already susceptible to bleeding. Sclerotherapy is another option to manage the bleeding. This process involves injecting a small amount of an aerated irritant (detergent such as sodium tetradecyl sulfate) directly into the telangiectasias. The detergent causes the vessel to collapse and harden, resulting in scar tissue residue. This is the same procedure used to treat varicose veins and similar disorders.
It may be possible to embolize vascular lesions through interventional radiology; this requires passing a catheter through a large artery and locating the maxillary artery under X-ray guidance, followed by the injection into the vessel of particles that occlude the blood vessels. The benefit from the procedure tends to be short-lived, and it may be most appropriate in episodes of severe bleeding.
To more effectively minimize recurrence and severity of epistaxis, other options may be used in conjunction with therapies listed above. Intravenously administered anti-VEGF substances such as bevacizumab (brand name Avastin), pazopinab and thalidomide or its derivatives interfere with the production of new blood vessels that are weak and therefore prone to bleeding. Due to the past experiences with prescribing thalidomide to pregnant women to alleviate symptoms of nausea and the terrible birth defects that followed, thalidomide is a last resort therapy. Additionally, thalidomide can cause neuropathy. Though this can be mitigated by tinkering with dosages and prescribing its derivatives such as lenolidomide and pomalidomide, many doctors prefer alternative VEGF inhibitors. Bevacizumab has been shown to significantly reduce the severity of epistaxis without side effects.
If other interventions have failed, several operations have been reported to provide benefit. One is septal dermoplasty or Saunders' procedure, in which skin is transplanted into the nostrils, and the other is Young's procedure, in which the nostrils are sealed off completely.
Lung lesions, once identified, are usually treated to prevent episodes of bleeding and more importantly embolism to the brain. This is particularly done in lesions with a feeding blood vessel of 3 mm or larger, as these are the most likely to cause long-term complications unless treated. The most effective current therapy is embolization with detachable metal coils. The procedure involves puncture of a large vein (usually under a general anesthetic), followed by advancing of a catheter through the right ventricle and into the pulmonary artery, after which radiocontrast is injected to visualize the AVMs (pulmonary angiography). Once the lesion has been identified, coils are deployed that obstruct the blood flow and allow the lesion to regress. In experienced hands, the procedure tends to be very effective and with limited side effects, but lesions may recur and further attempts may be required. CTA scans are repeated to monitor for recurrence. Surgical excision has now essentially been abandoned due to the success of embolotherapy.
Those with either definite pulmonary AVMs or an abnormal contrast echocardiogram with no clearly visible lesions are deemed to be at risk from brain emboli. They are therefore counselled to avoid scuba diving, during which small air bubbles may form in the bloodsteam that may migrate to the brain and cause stroke. Similarly, antimicrobial prophylaxis is advised during procedures in which bacteria may enter the bloodstream, such as dental work, and avoidance of air bubbles during intravenous therapy.
There is no cure for this disease. Drugs such as antiplatelet agents (including aspirin) are usually given to prevent clots, but surgery is usually recommended. Since moyamoya tends to affect only the internal carotid artery and nearby sections of the adjacent anterior and middle cerebral arteries, surgeons can direct other arteries, such as the external carotid artery or the superficial temporal artery to replace its circulation. The arteries are either sewn directly into the brain circulation, or placed on the surface of the brain to reestablish new circulation after a few weeks.
There are many operations that have been developed for the condition, but currently the most favored are the in-direct procedures EDAS, EMS, and multiple burr holes and the direct procedure STA-MCA. Direct superficial temporal artery (STA) to middle cerebral artery (MCA) bypass is considered the treatment of choice, although its efficacy, particularly for hemorrhagic disease, remains uncertain. Multiple burr holes have been used in frontal and parietal lobes with good neovascularisation achieved.
The EDAS (encephaloduroarteriosynangiosis) procedure is a synangiosis procedure that requires dissection of a scalp artery over a course of several centimeters and then making a small temporary opening in the skull directly beneath the artery. The artery is then sutured to a branch of the middle cerebral artery on the surface of the brain and the bone is replaced.
In the EMS (encephalomyosynangiosis) procedure, the temporalis muscle, which is in the temple region of the forehead, is dissected and through an opening in the skull placed onto the surface of the brain.
In the multiple burr holes procedure, multiple small holes (burr holes) are placed in the skull to allow for growth of new vessels into the brain from the scalp.
In the STA-MCA procedure, the scalp artery (superficial temporal artery or STA) is directly sutured to an artery on the surface of the brain (middle cerebral artery or MCA). This procedure is also commonly referred to as an EC-IC (External Carotid-Internal Carotid) bypass.
All of these operations have in common the concept of a blood and oxygen "starved" brain reaching out to grasp and develop new and more efficient means of bringing blood to the brain and bypassing the areas of blockage. The modified direct anastomosis and encephalo-myo-arterio-synangiosis play a role in this improvement by increasing cerebral blood flow (CBF) after the operation. A significant correlation is found between the postoperative effect and the stages of preoperative angiograms. It is crucial for surgery that the anesthesiologist have experience in managing children being treated for moyamoya, as the type of anesthesia they require is very different from the standard anesthetic children get for almost any other type of neurosurgical procedure.
Some of the most up to date treatments for Moyamoya are explained by top rated surgeons at Boston Children's Hospital in Massachusetts in these
Arteriovenous malformation (AVM) is an abnormal connection between arteries and veins, bypassing the capillary system. This vascular anomaly is widely known because of its occurrence in the central nervous system (usually cerebral AVM), but can appear in any location. Although many AVMs are asymptomatic, they can cause intense pain or bleeding or lead to other serious medical problems.
AVMs are usually congenital and belong to the RASopathies.
The genetic transmission patterns of AVM, if any, are unknown. AVM is not generally thought to be an inherited disorder, unless in the context of a specific hereditary syndrome.
The treatment for Bonnet–Dechaume–Blanc syndrome is controversial due to a lack of consensus on the different therapeutic procedures for treating arteriovenous malformations. The first successful treatment was performed by Morgan et al. They combined intracranial resection, ligation of ophthalmic artery, and selective arterial ligature of the external carotid artery, but the patient did not have retinal vascular malformations.
If lesions are present, they are watched closely for changes in size. Prognosis is best when lesions are less than 3 cm in length. Most complications occur when the lesions are greater than 6 cm in size. Surgical intervention for intracranial lesions has been done successfully. Nonsurgical treatments include embolization, radiation therapy, and continued observation. Arterial vascular malformations may be treated with the cyberknife treatment. Possible treatment for cerebral arterial vascular malformations include stereotactic radiosurgery, endovascular embolization, and microsurgical resection.
When pursuing treatment, it is important to consider the size of the malformations, their locations, and the neurological involvement. Because it is a congenital disorder, there are not preventative steps to take aside from regular follow ups with a doctor to keep an eye on the symptoms so that future complications are avoided.
There are currently two treatment options for brain aneurysms: surgical clipping or endovascular coiling. There is currently debate in the medical literature about which treatment is most appropriate given particular situations.
Surgical clipping was introduced by Walter Dandy of the Johns Hopkins Hospital in 1937. It consists of a craniotomy to expose the aneurysm and closing the base or neck of the aneurysm with a clip. The surgical technique has been modified and improved over the years.
Endovascular coiling was introduced by Guido Guglielmi at UCLA in 1991. It consists of passing a catheter into the femoral artery in the groin, through the aorta, into the brain arteries, and finally into the aneurysm itself. Platinum coils initiate a clotting reaction within the aneurysm that, if successful fill the aneurysm dome and prevent its rupture. Flow diverter can be used but not without complications sometimes.
Treatment for cerebrovascular disease may include medication, lifestyle changes and/or surgery, depending on the cause.
Examples of medications are:
- antiplatelets (aspirin, clopidogrel)
- blood thinners (heparin, warfarin)
- antihypertensives (ACE inhibitors, beta blockers)
- anti-diabetic medications.
Surgical procedures include:
- endovascular surgery and vascular surgery (for future stroke prevention).
While there is no current cure, the treatments for Chiari malformation are surgery and management of symptoms, based on the occurrence of clinical symptoms rather than the radiological findings. The presence of a syrinx is known to give specific signs and symptoms that vary from dysesthetic sensations to algothermal dissociation to spasticity and paresis. These are important indications that decompressive surgery is needed for patients with Chiari Malformation Type II. Type II patients have severe brain stem damage and rapidly diminishing neurological response.
Decompressive surgery involves removing the lamina of the first and sometimes the second or third cervical vertebrae and part of the occipital bone of the skull to relieve pressure. The flow of spinal fluid may be augmented by a shunt. Since this surgery usually involves the opening of the dura mater and the expansion of the space beneath, a dural graft is usually applied to cover the expanded posterior fossa.
A small number of neurological surgeons believe that detethering the spinal cord as an alternate approach relieves the compression of the brain against the skull opening (foramen magnum), obviating the need for decompression surgery and associated trauma. However, this approach is significantly less documented in the medical literature, with reports on only a handful of patients. It should be noted that the alternative spinal surgery is also not without risk.
Complications of decompression surgery can arise. They include bleeding, damage to structures in the brain and spinal canal, meningitis, CSF fistulas, occipito-cervical instability and pseudomeningeocele. Rare post-operative complications include hydrocephalus and brain stem compression by retroflexion of odontoid. Also, an extended CVD created by a wide opening and big duroplasty can cause a cerebellar "slump". This complication needs to be corrected by cranioplasty.
In certain cases, irreducible compression of the brainstem occurs from in front (anteriorly or ventral) resulting in a smaller posterior fossa and associated Chiari malformation. In these cases, an anterior decompression is required. The most commonly used approach is to operate through the mouth (transoral) to remove the bone compressing the brainstem, typically the odontoid. This results in decompressing the brainstem and therefore gives more room for the cerebellum, thus decompressing the Chiari malformation. Arnold Menzes, MD, is the neurosurgeon who pioneered this approach in the 1970s at the University of Iowa. Between 1984 and 2008 (the MR imaging era), 298 patients with irreducible ventral compression of the brainstem and Chiari type 1 malformation underwent a transoral approach for ventral cervicomedullary decompression at the University of Iowa. The results have been excellent resulting in improved brainstem function and resolution of the Chiari malformation in the majority of patients.
Sclerotherapy is a treatment for specific veins and vascular malformations in the affected area. It involves the injection of a chemical into the abnormal veins to cause thickening and obstruction of the targeted vessels. Such treatment may allow normal blood flow to resume. It is a non-surgical medical procedure and is not nearly as invasive as debulking. Ultrasound guided foam sclerotherapy is the state of the art new treatment which could potentially close many large vascular malformations.
Compression therapies are finding more use as of the last ten years. The greatest issue with KTS syndrome is that the blood flow and/or lymph flow may be impeded, and will pool in the affected area. This can cause pain, swelling, inflammations, and in some cases, even ulceration and infection. Among older children and adults, compression garments can be used to alleviate almost all of these, and when combined with elevation of the affected area and proper management, can result in a comfortable lifestyle for the patient without any surgery. Compression garments are also used lately after a debulking procedure to maintain the results of the procedure. For early treatment of infants and toddlers with KTS, custom compression garments are impractical because of the rate of growth. When children may benefit from compression therapies, wraps and lymphatic massage may be used. While compression garments or therapy are not appropriate for everyone, they are relatively cheap (compared to surgery), and have few side-effects. Possible side-effects include a slight risk that the fluids may simply be displaced to an undesirable location (e.g., the groin), or that the compression therapy itself further impedes circulation to the affected extremities.
Debulking has been the most common treatment for KTS for several decades and while improvements have been made, the procedure is still considered invasive and has several risks associated with it. More effective and less invasive treatment choices now exist for KTS patients and therefore debulking is generally only recommended as a last resort. Debulking operations can result in major deformities and also leave patients with permanent nerve damage.
Mayo Clinic has reported the largest experience in managing KTS with major surgery. In 39 years at Mayo clinic the surgery team evaluated 252 consecutive cases of KTS, of which only 145 (57.5%) could be treated by primary surgery. The immediate success rate for treating varicose veins was only 40%, excision of vascular malformation was possible in 60%, debulking operations in 65%, and correction of bone deformity and limb length correction (epiphysiodesis) had 90% success. All the procedures demonstrated high recurrence rate in the follow-up. Mayo clinic studies demonstrate that primary surgical management of KTS has limitations and non-surgical approaches need to be developed in order to offer a better quality of life for these patients. Major surgery including amputation and debulking surgery does not seem to offer any benefit on a long-term basis.