Learning objectives
To illustrate anatomical characteristics of medullary arteries of the brain by observing cadaveric microangiograms and by tracing perivascular spaces along medullary arteries on MR images.
To review imaging features of several pathologies involving medullary arteries with classification of ischemic cerebral injuries/ infarcts in terms of medullary artery circulation.
Background
Medullary arteries of the cerebrum supply the entire cerebral white matter,
and are largely responsible for small vessel disease,
which is closely associated with strokes and vascular dementia.
However,
ischemic cerebral lesions/ infarcts are usually discussed from the viewpoint of large arteries,
but rarely of medullary arteries.
Imaging findings OR Procedure details
<Anatomy>
[A] Cadaveric microangiograms
The main arterial trunks of the brain supply the cerebrum via basal perforating arteries and pial arteries (1).
From pial arteries over cerebral convexity,
small arteries and arterioles arise including intracortical arteries,
subcortical arteries,
and medullary arteries.
The cortex is supplied from intracortical arteries,
and the subcortical U-fiber region from subcortical arteries and short side-branches of the medullary arteries (Fig.
1).
Fig.
1 Diagram of coronal section of the cerebrum illustrating its vascular supply (Adapted from Moody DM (2))
The cerebral...
Conclusion
Recognizing the anatomic characteristics of the medullary arteries and their resulting circulation pattern would facilitate to understand the mechanism of various patterns of ischemic cerebral lesions.
References
1. Takahashi S,
ed. Neurovascular Imaging: MRI & Microangiography.
London: Springer; 2011.
2. Moody DM,
Bell MA,
Challa VR.
Features of the cerebral vascular pattern that predict vulnerability to perfusion or oxygenation deficiency: an anatomic study.
AJNR Am J Neuroradiol.
1990 May;11(3):431-9.
3. Moody DM,
Santamore WP,
Bell MA.
Does tortuosity in cerebral arterioles impair down-autoregulation in hypertensives and elderly normotensives? A hypothesis and computer model.
Clin Neurosurg.
1991;37:372-87.
4. Pantoni L,
Garcia JH.
Pathogenesis of leukoaraiosis: a review.
Stroke.
1997 Mar;28(3):652-9.
5. Mugikura S,...
