Friday, April 24, 2015

Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a type of stroke where bleeding occurs within the brain tissue itself. The blood clot causes damage to the brain tissue in that area leading to signs and symptoms. Also, the blood clot may lead to increased pressure in the brain and subsequent symptoms. The bleeding may occur due to a number of reasons such as

  • high blood pressure
  • head trauma
  • arteriovenous malformation rupture
  • brain aneurysm rupture
  • diseases that cause increased tendency of bleeding (Eg., Hemophilia)
  • treatment with blood thinner medicines (Eg., Aspirin, Warfarin, Clopidogrel, Heparin)
  • tumors within the brain
  • cocaine and amphetamine abuse
  • amyloid angiopathy (bleeding due to degeneration of arteries in elderly people)
How common is intracerebral hemorrhage?

About 10% of all strokes occur due to intracerebral hemorrhage while 80% occur due to ischemic stroke (due to blockage of arteries supplying the brain). This translates to about 12-15 cases per 100,000/year in general population. About 40% of patients with intracerebral hemorrhage eventually die and a large proportion of the rest are left with permanent disability. Advancing age and uncontrolled high blood pressure are major risk factors for ICH.

Signs and Symptoms
  • Headache
  • Nausea and vomiting
  • weakness of arm, leg
  • facial droop
  • confusion, lethargy and loss of consciousness
  • speech difficulty
  • seizures
  • visual loss
  • difficulty in walking
How is the diagnosis made?
  • A CT scan is the best imaging modality to detect acute bleeding within the brain
  • CT angiogram / MRI / MR angiogram and a digital subtraction angiogram may be required to detect the exact cause of bleeding.
How is intracerebral hemorrhage treated?
  • The first step in the treatment of intracerebral hemorrhage is to determine the cause of bleed
  • High blood pressure is controlled with medications
  • If the bleeding leads to increased pressure in the brain, surgery may be needed to remove the clot and relieve the pressure. Surgical procedure may involve craniotomy and evacuation, stereotactic aspiration, draining fluid from the brain.
Recovery and Outcome

Outcome following intracerebral hemorrhage depends upon the cause, location and extent of bleed. Prompt diagnosis and treatment helps to minimize complications and long term sequelae.

Friday, April 17, 2015

Smoking and Brain Aneurysms

The prevalence of brain aneurysms in India is unknown. Extrapolating the estimates in Western countries to India, about 2,00,000 patients suffer from brain aneurysm rupture every year in India. A brain aneurysm rupture is fatal in about 40% of the cases and leads to significant disability in a considerable proportion of survivors. Considering that 62% of India's population is under 60 years of age and that most aneurysm ruptures occur between 35 and 60 years of age, a large proportion of patients lose their productive life due to brain aneurysm rupture.

Smoking is one of the only two modifiable predisposing conditions to brain aneurysm formation and rupture, the other being uncontrolled high blood pressure. According to the data from Global Adult Tobacco Survey (GATS), in 2009-10, about one third of Indians (aged 15 and above) were smokers (48% males and 20% females). As such, every patient with a diagnosed brain aneurysm should be counselled to quit smoking.

Smoking no only predisposes to brain aneurysm rupture, but also acts as a catalyst in aneurysm formation and growth. Some of the known facts about smoking and brain aneurysms are

  • Smoking weakens the walls of the arteries in the brain leading to increased risk of outpouching. Also, weak arterial walls promote aneurysm growth and eventually rupture
  • Smokers are three times more prone to aneurysm rupture than non-smokers
  • Smokers are also predisposed to having stroke more often than non-smokers following aneurysm rupture
  • Multiple brain aneurysms (>2 aneurysms) are more common in smokers than in the general population
  • Female smokers are at the highest risk of aneurysm rupture
  • The phenomenon of vasospasm (narrowing of arteries) following brain aneurysm rupture is more common in smokers
  • Smokers are also prone to develop more complications during treatment of the aneurysm (surgical clipping or coiling)
  • Even after aneurysm repair by clipping or coiling, the risk of aneurysm re-growth or development of new aneurysms remains in smokers
  • High blood pressure and smoking are the only two risk factors for brain aneurysm rupture that can be modified and controlled. Hence, they need to be given utmost importance.

Friday, April 10, 2015

Brain AVMs during pregnancy

An AVM (arteriovenous malformation) of the brain is an abnormal tangle of blood vessels in the brain connecting the arteries to the veins. The tangle of abnormal blood vessels is called a 'nidus'. If the arteries and veins are connected one-to-one without the intervening tangle of blood vessels, it is called a fistula. Because these blood vessels are abnormal, they have a tendency to rupture leading to bleeding within the brain. AVMs are not unique to the brain and can occur in other parts of the body. However, brain AVMs are unique in that they cause severe devastating effects if they rupture.

Brain AVMs diagnosed during pregnancy present a challenge to the neurosurgeon as well as to the obstetrician. The normal changes in the mother during pregnancy may predispose to rupture of the AVM, thus causing brain bleed. If untreated, the AVM runs the risk of bleeding and at the same time, treatment of the AVM may itself pose significant risk to the mother and the fetus. The overall risk of AVM rupture during pregnancy is about 1 in 100,000 deliveries.

What precautions should be taken in a pregnant mother diagnosed with brain AVM

  • The highest risk of rupture of an AVM is in the second trimester due to the normal pregnancy related changes in the mother.
  • The risk of AVM rupture does not increase during labor and delivery and hence, normal delivery should be encouraged
  • As the changes occurring in the mother do not immediately revert following delivery, the risk of AVM rupture remains high immediately following delivery
  • If the mother presents with seizures, due consideration should be given to the anti-seizure drug as it may harm the fetus
  • The symptoms of AVM rupture mimic other common symptoms such as pregnancy induced hypertension and hence a high index of suspicion is required to diagnose a brain AVM
  • when a mother presents with severe headache, seizures, speech difficulty or weakness of arm or leg, brain imaging is warranted
  • MRI is the preferred method of choice to diagnose brain AVM in pregnancy as it avoids the radiation risk
  • Surgery or endovascular therapy for an AVM in a pregnant mother should be carefully thought and undertaken with the understanding all the associated risks such as that of anesthesia, blood loss and radiation. There are no guidelines for the management of brain AVMs during pregnancy
  • Stresses associated with normal delivery should be minimized. Primarily, the straining involved in the second stage of labor should be addressed. A combination of an outlet forceps delivery and the use of epidural anesthesia is recommended as means to reduce the duration of labor.
  • There is no clear evidence to recommend that women with unruptured AVMs not have children.
  • On the other hand, if a woman presents with a history of an AVM rupture in the recent past (within a year), there is evidence to support the recommendation that the patient undergo treatment for the AVM

Friday, April 3, 2015

Brain aneurysms in pregnancy

Pregnancy is a unique phase in a woman's life. It is associated with normal changes in almost every body system that assist fetal survival as well as preparation for labor. High blood pressure (hypertension) is the most common medical problem encountered during pregnancy and complicates 2%-3% of pregnancies. Diagnosis or rupture of a brain aneurysm during pregnancy poses serious life-threatening risk to the mother and the baby. It is therefore imperative that all Obstetricians are aware of this entity so that a high index of suspicion is maintained when pregnant women present with acute headache. The present article discusses some of the common questions about brain aneurysms in pregnancy.

Are brain aneurysms common in pregnancy?

Brain aneurysms rarely present during pregnancy.The reported incidence of brain aneurysm rupture during pregnancy ranges from 3-11 per 100,000 pregnancies. Of all the women presenting with ruptured brain aneurysm during pregnancy, 35% eventually die. It also results in death of the fetus in 17% of the cases. Although brain aneurysms are rare in pregnancy, they account for 5%-12% of all maternal deaths during pregnancy.

Is the risk of brain aneurysm rupture higher in pregnant women than in the general population?

It is unclear whether the risk of aneurysm rupture is higher in pregnant women than in general population. Many studies from Europe have reported increased risk of aneurysm rupture during pregnancy. However, a recent study from the United States reported no evidence of increased risk. The critical periods during pregnancy that can be detrimental to the mother and the fetus are labor and delivery.

How are brain aneurysms managed in pregnant women?

The management of brain aneurysms in pregnant women is similar to that in general population. Additional aspects that should be considered are

  • Asymptomatic unruptured intracranial aneurysm in pregnancy can be managed conservatively with close monitoring with noninvasive imaging techniques such as magnetic resonance imaging. However, expanding or symptomatic unruptured aneurysms in pregnant women should be treated

  • Radiation exposure to the fetus from CT scan and angiography should be minimized. MRI is the preferred imaging modality. If CT scan and angiography are absolutely required, a lead shield should be used to protect the fetus from radiation.

  • There are no evidence-based recommendations for child birth in patients with unruptured brain aneurysm, and there is no evidence to suggest that maternal or fetal outcome is improved by cesarean delivery in comparison with closely supervised vaginal delivery. Some studies have recommended caesarean delivery to avoid the stress of labor and delivery.

  • All women with ruptured brain aneurysms should be treated to prevent rebleeding. Clipping avoids the risk of radiation injury, but puts the mother and the fetus under stress during anesthesia and open surgery. Endovascular coiling poses radiation risk to the fetus.