Anterior choroidal artery

Blockade of the anterior choroidal artery may cause infarction of the lateral geniculate body causing hemianopia with preserved central vision and a prominent sensory loss with hemiparesis (Bruno et al. 1989). 

Brazis PW, Masdeu JC, Biller J (1990) Localization in clinical neurology, 3rd edn. Little Brown, Boston Bruno A, Graff-Radford NR, Biller J et al (1989) Anterior choroidal artery territory infarction a small vessel disease. Stroke 20 616-619... 

Small hypophyseal and meningeal branches of the ICA are not visible in MR angiographies. The first originating vessel is the ophthalmic artery from the C3 segment. Distally the posterior communicating artery and subsequently the anterior choroidal artery arise from the ICA. A direct origin of the posterior cerebral artery from the ICA is referred to as embryonic type. 

The anterior choroidal artery is mostly detectable only on source images, not on MIP of a TOF-MRA (Wiesmann et al. 2001), because of its very small size. Consequently, definite statements about pathology can not be made. 

Wiesmann M, Yousry I, Seelos KC et al. (2001) Identification and anatomic description of the anterior choroidal artery by use of 3D-TOF source and 3D-CISS MR imaging. AJNR Am J Neuroradiol 22 305-310... 

These include infarcts in the territory of (1) the deep perforators of the MCA, anterior cerebral artery (ACA) and posterior cerebral artery (PCA), posterior communicating artery (PcomA), the lenticulo-striate arteries and the anterior choroidal artery (2) the superficial perforators (white matter medullary branches) of the superficial pial arteries (3) border-zone or junctional infarcts between 1 and 2 (4) combined infarcts. Small (< 1.5 mm infarcts - lacunes) are usually caused by single perforator disease while larger infarcts have a more diverse pathophysiology including embolism and MCA stenosis (Bang et al. 2002). 

Aphasia and neglect can be found following respectively dominant and non-dominant anterior choroidal artery infarcts. Anterior choroidal artery infarcts usually cause the classical 3H syndrome hemiparesis, hemihypesthesia, hemianopia. Pure motor hemiparesis and isolated hemianopia can also occur (Han et al. 2000). Anterior choroidal artery territory infarcts are rarely caused by small vessel occlusion. In general they are caused by cardioembolism or large artery disease with occlusion or artery-to-artery embolism (Leys et al. 1994). 

Recently, using color-coded diffusion tensor imaging five different patterns of corticospinal tract stroke were identified that fall into two clinical subgroups with either little recovery or good recovery. Patients with poor motor recovery had lesions centered in the pyramidal tract (anterior choroidal artery). Patients with good recovery had either very small lesions or lesions located anteriorly or medially (Lie et al. 2004). 

Lee PH, Bang OY, Oh SH et al (2003) Subcortical white matter infarcts. Comparison of superficial perforating artery and internal borderzone infarcts using diffusion-weighted magnetic resonance imaging. Stroke 34 2630-2635 Leys D, Mounier-Vehier F, Lavenu I et al (1994) Anterior choroidal artery territory infarcts. Study of presumed mechanisms. Stroke 25 837-842... 

The anterior choroidal artery arises from the last section of the internal carotid artery, just beyond the posterior communicating artery origin, and supplies the optic tract, internal capsule, medial parts of the basal ganglia, the medial part of the temporal lobe, thalamus, lateral geniculate body, proximal optic radiation and midbrain. Occasionally it arises from the proximal middle cerebral artery or posterior communicating artery. Minor twiglets... 

The anterior choroidal artery. This branch of the internal carotid artery can anastomose with the posterior choroidal artery, a branch of the posterior cerebral artery. 

Some anterior circulation syndromes, usually classified as partial anterior circulation syndromes, are caused by boundary zone infarcts. The rare anterior choroidal artery distribution infarcts, which can be defined only by the CT or MRI pattern, are probably caused by microvascular disease as well as embolism, and they can lead to a partial anterior circulation syndrome or lacunar syndrome (Hupperts et al. 1994). 

Hupperts RMM, Lodder J, Heuts-van Raak EPM et al. (1994). Infarcts in the anterior choroidal artery territory. Anatomical distribution, clinical syndromes, presumed pathogenesis and early outcome. Brain 117 825-834... 

Fig. 4 E. View into the ambient and crural cisterns following selective amygdalohippocampectomy. Vascular anatomy demonstrated is P-2 segment (P2), anterior choroidal artery with branches (arrows). Also seen is the III nerve superiorly III) and the optic tract inferomedically Op). The basilar vein is partially hidden beneath the anterior choroidal artery...

Fig. 5B. The basilar vein (B) is demonstrated bet ween P-2 segment (P2) and anterior choroidal artery (arrow). Also the III nerve (III) and the optic tract (Op) are seen. Tiny nerve fibers originating from the lateral peduncle (small arrows), crossing the ambient cistern, and joining the III nerve...

Fig. 8. Visualization of the ICA, PcoA, anterior choroidal artery, uncal artery, M-1 and M-2 segments with temporal branches. Dotted line indicates the place of...

One can now begin to see how the combined subfrontal and in-sula/temporal approach described enables the surgeon to see not only the course of the anterior choroidal artery but also the optic tract. This is particularly important in those cases demonstrating deep mesial herniation. 

Fig. 9. The amygdala is removed (dotted lines), exposure of the entire temporal horn with demonstration of the anterior choroidal artery, basilar vein of Rosenthal and optic tract. The direction of the arrows indicate the dissection steps around the...

The choroid plexus may be displaced from medially to laterally to demonstrate the tela choroidea over the sulcus choroideus. Through this transparent membrane can be seen the anterior choroidal artery and ventricular tributaries of the basiliar vein. 

The anterior choroidal artery gives not only medial branches to the optic tract, peduncle, internal capsule, thalamus and a large branch to the choroid... 

MGY) series of over 115 selective operations. The results are described in the second part of this paper. Those which might be particularly anticipated are hemiparesis and homonymous field defects. These may be kept to a minimum if care is taken to avoid damage to the branches of the anterior choroidal artery and branches of the P-2 segment. Visual field defects are more likely to result from damage to or spasm of vessels that supply the optic tract than to direct injury to Meyer s loop. 

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