Cavernous Angiomas and Surgery: Common Questions

Many people affected by cavernous angioma have questions regarding surgery. This article addresses the most common questions, with answers based on the published clinical literature cited at the end of this article. For information specific to you or your family, please consult your physician.

Some key terms
Hemorrhage: The medical term for “bleeding.”
Resection: The surgical removal of a lesion.
Lesion: A medical term for an abnormality on or in a body part caused by disease or injury.
Seizure: Uncontrolled electrical activity in the brain, which may cause cognitive or physical symptoms.
Brainstem: The part of the brain between the cortex (the white matter) and the spinal cord.

What is a clinical hemorrhage?

A hemorrhage is when there is a bleed in your brain. Clinically, the definition of a hemorrhage is an event that includes both the onset of symptoms (e.g. headache, seizure, etc) and radiological or physical evidence of a vascular bleed.

Bleeding from a cavernous angioma can cause symptoms in two ways. The first is when blood leaks from a lesion and makes contact with brain tissue. It is also thought that an increased amount of bleed inside a lesion can cause pressure on the surrounding tissue.

When is surgery recommended for brainstem lesions?

Brainstem lesions may cause particular concern because they are more likely to develop clinical hemorrhage (bleeding together with neurological symptoms) than lesions located in other parts of the brain. The brainstem is the location of many cranial nerves as well as those for essential motor and sensory capacities, thus this represents a particularly sensitive brain region. Brainstem lesions are therefore often treated more aggressively than lesions in other parts of the brain. The decision to undergo brain surgery is certainly difficult; one must weigh the risk of potential harm from surgery and one’s current clinical status compared to the risk of additional bleeds.

Surgery on a surgically accessible brainstem lesion may be recommended if:

  • The lesion has hemorrhaged multiple times and shows to be causing worsening neurological deficits (including motor or sensory deficits, headaches, double vision, vertigo, etc.), or
  • The lesion has hemorrhaged and blood has extended into the surrounding brain.

In general, surgery may be recommended if the risk of brain surgery is outweighed by possible negative consequences of new hemorrhages.

When is surgery not recommended for brainstem lesions?

In a recent report from the Barrow Neurological Institute at St. Joseph’s Hospital in Phoenix, Arizona, roughly half of all patients with brainstem lesions in the past 15 years have been recommended for surgery.

For patients not undergoing surgical excision of the lesion (from this study and others), conservative management and observation was recommended for one or more of the following reasons:

  • The patient experienced few or no symptoms,
  • The lesion was small and/or inaccessible,
  • The lesion had minor hemorrhages in the past that showed rapid improvement, or
  • The lesion was asymptomatic and located in an area below the 4th ventricle—surgery through this region tends to cause the most severe deficits.

Each of these conditions was considered to be less risky to the patient than surgery.

What are some statistics for surgical outcomes?

Brain surgery involves serious risks; however, individuals who choose surgery often believe that the risks are worth taking, as surgical removal of a cavernous angioma can significantly reduce future risk of hemorrhage.

Two recent reports examined the surgical outcomes from large series of patients; the results are summarized below.

In a series of 260 adult patients who were treated between 1985 and 2009 at the Barrow Neurological Institute at St. Joseph’s Hospital in Phoenix, Arizona, the following outcomes were observed:

  • 89% of patients had the entirety of their lesion removed.
  • 45% of patients showed an improvement in symptoms after surgery.
  • 36% of patients showed new, permanent deficits, or worsening symptoms including motor or sensory disabilities, cognitive impairment, ataxia, pain and/or behavioral changes.
  • 7% of patients experienced a re-hemorrhage.
  • 5% of patients required additional surgeries.

Another publication, compiling data from 45 studies published between 1970 and 2008, reported similar results. In total, 745 patients sought treatment for their brainstem cavernous angioma. In this group:

  • 92% of patients had a complete resection of their lesion.
  • Of those with partial resections, about 50% of the patients experienced a re-hemorrhage of the remaining lesion.
  • For those patients with complete resection of their lesion:
  • 85% of patients were the same or showed improvement post-surgery.
  • 14% of patients were worse following surgery
  • 1.9% of patients died due to long-term surgery related outcomes.

While these results highlight the risks associated with surgery, the overall success for these groups of patients is illustrated by a reduction in the individual rate of hemorrhage.

What if a developmental venous anomaly is present?

A developmental venous anomaly (DVA or venous angioma) is a large vein structure that is often found near a cavernous angioma. During surgical removal of the cavernous angioma, it is generally recommended to leave the DVA intact. It may have an important role for normal venous drainage, and removal of a DVA may cause an unnecessary risk of venous infarction, or a blockage of blood flow.

Can surgery be useful for CCM-related epilepsy treatment?

Seizures and epilepsy (recurring seizures) are among the most common symptoms associated with cavernous angioma. It is not known why cavernous angiomas cause seizures. One hypothesis may be that bleeding from the lesions causes seizures; however, research suggests that bleeding is not the primary factor involved. In one study, clinical hemorrhage was more often observed in patients who did not experience seizures. This same study shows that location of lesions is more predictive of one’s risk of epilepsy: those with cavernous angiomas in the temporal lobe are more likely to have seizures.

Seizures and epilepsy can be controlled with anti-seizure medications and/or surgical removal of lesions that cause seizures. In a series of 44 patients with epilepsy that was not controllable with medication, 72% of patients undergoing resection became seizure-free. The remaining patients who underwent surgery had rare seizures, some improvement or no improvement from pre-surgical conditions. In summary, surgical options may be an effective option for reducing seizures in cavernous angioma patients who suffer from epilepsy.

How can natural history studies help better answer these questions?

The decision to undergo surgery is personal, medical and scientific. One of the largest criticisms to studies such as those discussed here is that it remains unknown how surgical outcomes compare to conservative management of lesions (i.e. observation without surgical intervention). There is a need for a large-scale natural history study (a study that follows a group of people over time to see how their condition evolves) to better understand the normal progression of cavernous angioma patients through time. This is difficult because patients are treated in different countries, states or hospitals.

Angioma Alliance is working to help with this effort though our research initiatives including the Patient Registry and the DNA & Tissue Bank. To learn more about these programs and consider participating please visit: Without you, there can be no cure!


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