Charcot-Bouchard aneurysm

Charcot-Bouchard aneurysms (also known as miliary aneurysms or microaneurysms) are aneurysms of the brain vasculature which occur in small blood vessels (less than 300 micrometre diameter). They should not be confused with saccular aneurysms (a.k.a. berry aneurysms), which occur in larger-sized blood vessels. Charcot-Bouchard aneurysms are most often located in the lenticulostriate vessels of the basal ganglia and are associated with chronic hypertension.^[1] Charcot-Bouchard aneurysms are a common cause of stroke.

Presentation

Charcot-Bouchard aneurysms are aneurysms in the small penetrating blood vessels of the brainstem and midbrain. They are associated with hypertension. The common artery involved is Lenticulostriate branch of Middle cerebral artery. Common locations of hypertensive hemorrhages include the putamen, caudate, thalamus, pons, and cerebellum.

As with any aneurysm, once formed they have a tendency to expand and eventually rupture, in keeping with the Law of Laplace.^[2] If a Charcot-Bouchard aneurysm ruptures, it will lead to an intracerebral hemorrhage, which can cause hemorrhagic stroke, typically experienced as a sudden focal paralysis or loss of sensation. In contrast, if a saccular aneurysm ruptures, it will lead to a subarachnoid hemorrhage, typically experienced as an extremely severe headache leading to loss of consciousness. Both situations are medical emergencies, but a subarachnoid hemorrhage is more dangerous, with mortality between 25 and 50%.^[1]

Eponym

Charcot-Bouchard aneurysms are named for the French physicians Jean-Martin Charcot and Charles-Joseph Bouchard.^[3][4] It was Bouchard who discovered these aneurysms during his doctoral research under Charcot.

Other conditions

Other causes of intracranial hemorrhage include:

• Saccular aneurysm (aka berry aneurysm)
• Arteriovenous malformations

References

1. ^ ^{a b} Kumar; Abbas; Fausto, eds (2005). Robbins and Cotran Pathologic Basis of Disease (7th ed.). China: Elsevier. ISBN 0-7216-0187-1. 
2. ^ E. Goljan, Pathology, 2nd ed. Mosby Elsevier, Rapid Review Series.
3. ^ synd/28 at Who Named It?
4. ^ C. J. Bouchard. Étude sur quelques points de la pathogénie des hémorrhagies cérébrales. Paris, 1867.