Internal carotid agenesis

Title

Other Names:

Agenesis of the internal carotid artery; Internal carotid artery agenesis

Categories:

Blood Diseases; Congenital and Genetic Diseases; Nervous System Diseases

Summary Summary

Internal carotid agenesis occurs when one of the blood vessels which supply blood to the brain does not develop (agenesis). It is rare, occurring in less than 0.01% of people.^[1] Usually there is a pair of internal carotid arteries, one on the left side and one on the right side; agenesis occurs on the left side three times more frequently than on the right side.^[2] Individuals with this condition may not have any symptoms because there are several blood vessels transporting blood to the brain such that if one does not develop, the others can function in its place. However, if symptoms occur, they may include headache, blurred vision, paralysis of some of the nerves in the head (palsy), epilepsy, or muscle weakness on one side of the body (hemiparesis).^[2] The main concern with internal carotid agenesis is the increased risk for enlargement of the other blood vessels (aneurysm), which can occur in up to 67% of people with this condition (compared to 2-4% of individuals without this condition).^[3]

Last updated: 3/17/2011

Cause Cause

The cause of this condition is currently unknown. Most of the time, it is thought to occur by chance. However, there have been a few instances where individuals with internal carotid agenesis also had another condition, leading to questions about a possible association between the two.^[4]

Last updated: 3/17/2011

Diagnosis Diagnosis

Internal carotid agenesis is diagnosed when the absence of the internal carotid artery is noted on tests used to visualize the blood vessels and surrounding bones such as angiography, computed tomography scanning (CT scan), and magnetic resonance imaging (MRI).^[4] ^[3] Once internal carotid agenesis is diagnosed, these tests are done periodically to monitor the other blood vessels and check for aneurysms.^[4]

Last updated: 3/17/2011

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In-Depth Information

The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
PubMed is a searchable database of medical literature and lists journal articles that discuss Internal carotid agenesis. Click on the link to view a sample search on this topic.

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References References

Afifi, AK, Goersky JC, Menezes A, Smoker WR, Bell WE, and Jacoby CG. Cerebral Hemiatrophy, Hypoplasia of Internal Carotid Artery, and Intracranial Aneurysm: A Rare Association Occuring in an Infant. Arch Neurol. 1987; 44:232-235. http://www.ncbi.nlm.nih.gov/pubmed?term=10428407. Accessed 3/14/2011.
Florio F, Balzano S, Nardella M, Strizzi V, Cammisa M, Bozzini V, Catapano G, and D'Angelo V. Congenital Absence of the Internal Carotid Artery. Vardiovasc Intervent Radiol. 1999; 22:74-78. http://www.ncbi.nlm.nih.gov/pubmed?term=9929551. Accessed 3/14/2011.
Lee JH, Oh CW, Lee SH, and Han DH. Aplasia of the internal carotid artery. Acta Neruochin. 2003; 145:117-125. http://www.ncbi.nlm.nih.gov/pubmed/12601459. Accessed 3/14/2011.
Claros P, Bandos R, GIlea I, Claros Jr A, Capdevila A, Gardia Rodrigues J, Claros A. Major congenital anomalies of the internal carotid artery: agenesis, aplasia and hypoplasia. Int J Pediatr Otorhinolaryngol. 1999; 49:69-76. http://www.ncbi.nlm.nih.gov/pubmed?term=10428407. Accessed 3/14/2011.