A subarachnoid hemorrhage is bleeding in the space between your brain and the surrounding membrane (subarachnoid space). The primary symptom is a sudden, severe headache. The headache is sometimes associated with nausea, vomiting and a brief loss of consciousness
Bleeding usually results from the rupture of an abnormal bulge in a blood vessel (aneurysm) in your brain. Sometimes bleeding is caused by trauma, an abnormal tangle of blood vessels in your brain (arteriovenous malformation), or other blood vessel or health problems.
Untreated, a subarachnoid hemorrhage can lead to permanent brain damage or death.
To diagnose a subarachnoid hemorrhage, your doctor is likely to recommend:
Up to 22% of aneurysmal subarachnoid hemorrhages don't appear on initial imaging tests. If your initial tests don't show bleeding, your doctor might recommend:
Treatment initially focuses on stabilizing your condition.
If your bleeding is caused by a ruptured brain aneurysm, your doctor might recommend:
Endovascular procedures sometimes need to be performed again. You'll have regular follow-up appointments with your doctor to watch for any changes. You may also need physical, occupational and speech therapy.
Cerebral cavernous malformations (CCMs) are abnormally formed blood vessels. As opposed to other kinds of hemangiomas, CCM vessels, which have the appearance of a small mulberry, develop and create problems in the brain or spinal cord. These malformations, which can vary in size from 2 millimeters to several centimeters in diameter, may be hereditary but most often occur on their own.
CCMs may leak blood, leading to bleeding in the brain or spinal cord (hemorrhage). Brain or spinal hemorrhages can generate a wide range of more apparent neurological symptoms, depending on the location of a cavernous malformation in a person's nervous system.
Cerebral cavernous malformations (CCMs) may exist without apparent symptoms. Obvious symptoms tend to occur when recurrent episodes of bleeding or blood clot formation lead either to seizures, for upper lobe CCMs, or to focal or vision issues, for CCMs in the brainstem, basal ganglia and spinal cord.
Generally, signs and symptoms of CCMs may include weakness, numbness, difficulty speaking, difficulty understanding others, unsteadiness, vision changes or severe headache. Seizures also can occur, and neurological issues can progressively worsen over time with recurrent bleeding (hemorrhage). Repeat bleeding can occur soon after an initial bleed or much later, or a repeat bleed may never occur.
When to see a doctor
Seek medical help immediately if you experience any symptoms of seizure, or signs and symptoms that suggest brain hemorrhage, such as:
Most CCMs occur as a single formation, without an apparent cause and without any family history.
However, roughly 20 percent of affected people have a familial (inherited) form of the disorder. In many cases, such people can identify similarly affected family members, most often with multiple malformations. A diagnosis of the inherited form can be confirmed by genetic testing.
Some CCMs can also occur following focal brain radiation therapy.
As mentioned above, while most CCMs occur with no clear cause, the genetic (inherited familial) form of the condition can cause multiple cavernous malformations, both initially and over time.
To date, research has identified three genetic variants responsible for familial cavernous malformations, to which almost all familial cases of cavernous malformations have been traced.
The most concerning complications of CCMs stem from recurrent bleeding (hemorrhage), which may lead to progressive neurological damage.
Hemorrhages are more likely to recur in people with prior diagnosed hemorrhages. They're also more likely to reoccur with malformations located in the brainstem.
Often, people with cerebral cavernous malformations (CCMs) don't show any signs or symptoms. Your diagnosis may result from brain imaging for other neurological conditions, or specific symptoms may prompt your doctor to pursue more extensive testing.
Depending on why the condition is suspected, doctors may order tests specifically to confirm CCMs, or to identify or rule out other related conditions. Brain imaging is also called for as soon as possible after the emergence of any new symptoms, to reveal either hemorrhage or the emergence of any new malformations.
Doctors trained in brain and nervous system conditions (neurologists and cerebrovascular neurologists), brain and nervous system surgery (neurosurgeons), brain imaging (neuroradiologists), and other specialties work with you to treat CCMs as well as other neurological conditions.
Your treatment may include:
If your treatment plan includes surgery, more advanced imaging technologies, such as functional MRI and tractography, may also be useful within specific contexts.
Potential future treatments
Several imaging technology areas hold promise for both improving predictions of the course of disease in some specific contexts and for enhancing the level of information available about a particular individual's disease state, including potential advances in imaging through quantitative susceptibility mapping (QSM), permeability imaging using dynamic contrast-enhanced MRI, and the use of alternative MRI contrast agents such as ferumoxytol. While still under investigation, such developments hold promise for enhanced imaging that may lead to more precise and effective clinical care in the future.
Preparing for your appointment
What you can do
Write down questions to ask your doctor
Preparing a list of questions will help you make the most of your time with your doctor. List your questions from most important to least important in case time runs out. Most of these would be covered during your visit. Some examples of good questions to ask your doctor follow.
Management and observation
Surgery (to remove a malformation)
In addition to the questions you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.
What to expect from your doctor
Your doctor is also likely to ask you a number of questions:
What you can do in the meantime
Certain conditions and activities can trigger seizures, so it may be helpful to:
An arteriovenous malformation (AVM) is an abnormal tangle of blood vessels connecting arteries and veins, which disrupts normal blood flow and oxygen circulation.
Arteries are responsible for taking oxygen-rich blood from the heart to the brain. Veins carry the oxygen-depleted blood back to the lungs and heart.
When an AVM disrupts this critical process, the surrounding tissues may not get enough oxygen. Also, because the tangled blood vessels that form the AVM are abnormal, they can weaken and rupture. If the AVM is in the brain and ruptures, it can cause bleeding in the brain (hemorrhage), stroke or brain damage.
The cause of AVMs is not clear. They're rarely passed down among families.
Once diagnosed, a brain AVM can often be treated successfully to prevent or reduce the risk of complications.
Symptoms of AVM vary based on where it's located. Often the first signs and symptoms appear after bleeding occurs. Besides bleeding, signs and symptoms can include:
Other possible signs and symptoms include:
Children and teens may have trouble with learning or behavior.
One type of AVM called a vein of Galen defect causes symptoms that appear at or shortly after birth. A vein of Galen defect is located deep inside the brain. Signs can include:
When to see a doctor
Seek medical attention if you have any of the signs and symptoms of an AVM, such as headaches, dizziness, vision problems, seizures and changes in thinking or neurological function. Many AVMs are currently discovered incidentally, often after a CT scan or an MRI is obtained for reasons not directly related to the AVM.
AVMs result from development of abnormal direct connections between arteries and veins, but experts don't understand why this happens. Certain genetic changes might play a role, but most types are not usually inherited.
Rarely, having a family history of AVMs can increase your risk. But most types of AVMs aren't inherited.
Certain hereditary conditions may increase your risk of AVM. These include hereditary hemorrhagic telangiectasia (HHT), also called Osler-Weber-Rendu syndrome.
The most common complications of an AVM are bleeding and seizures. If left untreated, the bleeding can cause significant neurological damage and be fatal.
To diagnose an AVM, your doctor will review your symptoms and perform a physical examination.
He or she may listen for a sound called bruit. Bruit is a whooshing sound caused by very rapid blood flow through the arteries and veins of an AVM. It sounds like water rushing through a narrow pipe. Bruit may interfere with hearing or sleep or cause emotional distress.
Tests commonly used to help diagnose AVM include:
Treatment for AVM depends on where the abnormality is found, your signs and symptoms and your overall health, and the risk of treatment. Sometimes, an AVM is monitored with regular imaging tests to watch for changes or problems. Other AVMs require treatment. Determining whether an AVM needs treatment involves factors including whether the AVM:
Medications can help manage symptoms such as seizures, headaches and back pain.
The main treatment for AVM is surgery. Your doctor might recommend surgery if you're at a high risk of bleeding. The surgery might completely remove the AVM. This treatment is usually used when the AVM is in an area where surgeons can remove the AVM with little risk of causing significant damage to the brain tissues.
Endovascular embolization is a type of surgery in which the surgeon threads a catheter through the arteries to the AVM. Then a substance is injected to close parts of the AVM to reduce the blood flow. This might also be done before brain surgery or radiosurgery to help reduce the risk of complications.
Sometimes stereotactic radiosurgery is used to treat AVMs. This uses intense, highly focused beams of radiation to damage the blood vessels and stop the blood supply to the AVM.
You and your doctors will discuss whether to treat your AVM, weighing the possible benefits against the risks.
After treatment for an AVM, you might need regular follow-up visits with your doctor. You might need more imaging tests to make sure that the AVM is resolved and that the malformation has not recurred. You'll also need regular imaging tests and follow-up visits with your doctor if your AVM is being monitored.
Coping and support
Learning that you have an AVM can be frightening. It can make you feel like you have little control over your health. But you can take steps to cope with the emotions that accompany your diagnosis and recovery. Consider:
Preparing for your appointment
An AVM might be diagnosed in an emergency situation, immediately after bleeding (hemorrhage) or a seizure has occurred. It can also be detected after other symptoms prompt imaging scans.
But in some cases, an AVM is found during diagnosis or treatment of an unrelated medical condition. You may then be referred to a doctor trained in brain and nervous system conditions (neurologist, interventional neuroradiologist or neurosurgeon).
Because there's often a lot to discuss, it's a good idea to arrive well-prepared for your appointment. Here are some tips to help you get ready for your appointment, and what to expect from your doctor.
What you can do
Your time with your doctor is limited, so preparing a list of questions will help you make the most of your time together. For AVM, some basic questions to ask your doctor include:
What to expect from your doctor
Your neurologist is likely to ask about your symptoms, if any, conduct a physical examination and schedule tests to confirm the diagnosis.
The tests gather information about the size and location of the AVM to help direct your treatment options. He or she may ask: