Developmental Venous Anomaly

Developmental venous anomalies (DVA) are common vascular malformations most often found in the brain and spinal cord, but they can appear anywhere in the body.  A DVA is a circular collection of blood vessels that feeds into a larger central vein. Even though DVAs are abnormal blood vessels, they are fully integrated with the body’s venous system. They provide the brain with normal blood drainage.

DVA associated with a cavernous angioma

With the recent advent of higher resolution imaging techniques, the association between CCM and DVA has become a more common finding. A DVA is most often associated with the sporadic form of cavernous angioma. They can be found with a solitary cavernous angioma lesion or with a localized cluster of lesions.

A DVA is frequently found in the brainstem and, according to a 2019 study (Kumar et al), a DVA in the brainstem has been shown to increase the risk of having a cavernous angioma by 2.6 times. While the reason is not fully understood, the authors suggest it could be due to the size and shape of the DVA in this region.

The cause of CCM development in association with a DVA is not yet fully known. However, some researchers hypothesize that it could be due to thrombosis (blood clot) formation within the DVA. Thrombosis may occur as a result of inflammation, triggering hemorrhage or subsequent blood vessel growth. If this is the mechanism, antithrombotics may be useful only to those with DVAs, so predominantly people with the sporadic illness. Imaging studies, although perhaps only at a few centers with 7T MRI machines, could help answer this question. According to a 2019 study (Zuurbier et al), the association between antithrombotic therapy and a lower risk of hemorrhagic and focal neurological deficits in patients supports this idea.

Other Considerations

In general, surgical resection of a DVA, even during cavernous angioma resection, is not recommended due to the risk of edema, hemorrhage, or infarct. A 2020 study (Chen et al) found that sporadic lesions with an associated DVA did not increase patient risk of hemorrhage or hemorrhage size during a bleed. The authors recommend that having a DVA should not be an exclusive indication for proceeding with surgical resection of CCM.

Genetic testing is generally not recommended if there is an associated DVA present since these are more associated with the sporadic form of the disease. This further highlights the importance of obtaining gradient echo or SWI imaging in order to determine whether a DVA is present or associated with multiple lesions.

Patient Story: Vern

VernDVA with Cavernous Angioma

In 2004, Vern, then a 28-year-old father of two, hit his head while practicing jujitsu. From the subsequent CT scan, Vern and his wife Tiffany were surprised to learn that Vern had a more serious and long-term condition. Doctors diagnosed him with multiple cavernous angiomas surrounding a large developmental venous anomaly (DVA), a dilated malformed vein, in his brainstem. While a DVA by itself typically does not cause symptoms or complications, Vern’s DVA had set the stage for the development of more than one cavernous angioma.

It was not until two years later that Vern had his first hemorrhage. As a result, he closed his business as a mobile fleet service mechanic to focus on his recovery and his family. “I couldn’t drive,” Vern explains. “My reaction time was just not near what it needed to be to operate a vehicle safely.”  Vern is driving again, but not on interstates or during times of heavy traffic. He also has been recovering from gait and vision deficits.

Vern has consulted numerous surgeons about removing the most problematic of his cavernous angiomas. The DVA complicates surgery. Vern’s wife Tiffany explains, “The angioma that keeps bleeding is located too close to his DVA to remove. The DVA looks almost like a hook, and the angioma is on the inside of that hook.” Disturbing a large DVA like Vern’s can cause a catastrophic stroke.

Tiffany continues, “Vern has learned that being busy and doing something productive each day makes a huge difference in his quality of life. Vern has always had a very active lifestyle, but since having his bleeds, he has learned how to do things safer and smarter. He follows what doctors have told him to do and not to do… well mostly. All in all, Vern’s doing well.”

References

  • Chen B, Herten A, Saban D, et al. Hemorrhage from cerebral cavernous malformations: The role of associated developmental venous anomalies [published online ahead of print, 2020 Jun 8]. Neurology. 2020;10.1212
  • Awad IA, Polster SP. Cavernous angiomas: deconstructing a neurosurgical disease. J Neurosurg. 2019;131(1):1–13.
  • Kumar, S., Lanzino, G., Brinjikji, W., Hocquard, K. W., & Flemming, K. D. (2019). Infratentorial Developmental Venous Abnormalities and Inflammation Increase Odds of Sporadic Cavernous Malformation. Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association, 28(6), 1662–1667.
  • Zuurbier, Susanna M et al. Long-term antithrombotic therapy and risk of intracranial haemorrhage from cerebral cavernous malformations: a population-based cohort study, systematic review, and meta-analysis. The Lancet Neurology. 2019;18(10):935-941.
  • Akers A, et al. Synopsis of guidelines for the clinical management of cerebral cavernous malformations: consensus recommendations based on systematic literature review by the Angioma Alliance Scientific Advisory Board Clinical Experts Panel. Neurosurgery. 2017;80(5):665–680.