Artery superior cerebellar

FIGURE 4.2 Seventy-three-year-old female with sudden right hemiparesis, left facial weakness, dysarthria, nausea, and downheat nystagmus. Posterior circulation angioplasty demonstrated occlusion of the proximal hasilar artery (arrows— a and b). Note the retrograde opacification of the superior cerebellar arteries through postero-inferior cerebellar to superior cerebellar arteries collaterals (b). 

The size of the basilar artery varies markedly. Given an embryonic type of PCA, the basilar artery can be extremely small and sometimes it appears to end at the level of the superior cerebellar arteries. 

The anterior cerebellar artery (AICA) is normally the thinnest cerebellar artery and in MR angiographies is often insufficiently depicted. The superior cerebellar artery on the other hand can almost constantly be identified and anomalies such as duplications are mostly recognized on MR angiographies (Uchino et al. 2003). For the numerous anomalies and potential collateral circulations see specific literature (Osborn and Anderson 1977). 

Uchino A, Sawada A, Takase Y et al. (2003) Variations of the superior cerebellar artery MR angiographic demonstration. Radiat Med 21 235-238... 

The mesencephalon has four arterial territories anteromedial (paramedian branches of the basilar artery anterolateral (branches from the P2 segment of the PCA) lateral (branches from P2 segment of PCA and from posterior choroidal arteries) and dorsal (branches from PI segment of PCA and superior cerebellar artery). Isolated mesencephalic infarcts are rare because the arteries supplying blood to the mesencephalon (basilar artery, posterior cerebral artery and superior cerebellar artery)... 

Cerebellar infarcts can be grouped in territorial (superior cerebellar artery, anterior inferior cerebellar artery, posterior inferior cerebellar artery and combined), borderzone and lacunar. They are often combined with brain stem infarcts and with superficial posterior cerebral artery or thalamic infarcts. The most common isolated cerebellar infarcts are located in the superior cerebellar artery and posterior inferior cerebellar artery territories (Amarenco 1993 Amarenco et al. 1993,1994). 

The basilar artery ascends ventral to the pons to the ponto-midbrain junction in the interpeduncular cistern, where it divides into the two posterior cerebral arteries. Numerous small branches penetrate the brainstem and cerebellum. The basilar artery also gives rise to the anterior inferior cerebellar artery, which supplies the rostral cerebellum, brainstem, inner ear, and the superior cerebellar artery, which supplies the brainstem, superior half of the cerebellar hemisphere, vermis and dentate nucleus. 

The posterior cerebral artery supplies the occipital lobe and portions of the medial and inferior temporal lobe. The arterial supply of the spinal cord is derived from the vertebral arteries and the radicular arteries. The brain is supplied by the internal carotid arteries (the anterior circulation) and the vertebral arteries, which join at the pon tomedullary junction to form the basilar artery (collectively termed the posterior circulation). The brainstem is supplied by the posterior system. The medulla receives blood from branches of the vertebral arteries as well as from the spinal arteries and the posterior inferior cerebellar artery (PICA). The pons is supplied by paramedian and short circumferential branches of the basilar artery. Two major long circumferential branches are the anterior inferior cerebellar artery (AICA) and the superior cerebellar artery. The midbrain receives its arterial supply primarily from the posterior cerebral artery as well as from the basilar artery. The venous drainage of the spinal cord drains directly to the systemic circulation. By contrast, veins draining the cerebral hemispheres and brain stem drain into the dural sinuses. Cerebrospinal fluid also drains into the dural sinuses through unidirectional valves termed arachnoid villi. 

Posterior cerebral artery Superior cerebellar artery... 

Fig. 1.6 Cross-section illustrating the distribution of blood to the walls of the midbrain. The tectum is supplied by branches of the superior cerebellar artery. The medial aspects of the peduncular and tegmental regions are vascularized by branches of the basUar artery. The lateral peduncular and tegmental regions are supplied by branches of the posterior communicating artery. Note that these small arteries, which enter the walls of the central nervous system from the periphery, are functional end arteries and do not anastomose with adjacent arteries (See also Color Insert)...

Fig.3.22a-e. Small infratentorial brain AVM with two associated aneurysms along the PICA in a patient with SAH. Complete endovascular cure could be performed while coiling the proximal aneurysm and embolising the AVM with Onyx through the superior cerebellar artery. Note after AVM-treatment the more distal aneurysm disappeared... 

Fig.5.6a-d. Various locations of aneurysms. a Vertebrobasilar junction aneurysm. bTrue PICA aneurysm, c Basilar trunk aneurysm, d Basilar trunk aneurysm between origin of superior cerebellar artery and posterior cerebral artery, so-called superior cerebellar artery aneurysm... 

Fig. 5.16. a Giant ICA aneurysm inducing optic nerve compression in a 10-year-old boy with visual deficit on the right eye. b Brain stem aneurysm between origin of the superior cerebellar artery and posterior cerebral artery resulting in right sided oculomotor palsy. c,d Pcom aneurysm (c DSA, lateral view) in a 46-year-old-patient with oculomotor palsy note the close relationship of the aneurysm and the oculomotor nerve (arrow) but without visible contact (d, sagittal reconstruction of CISS sequence)... 

Fig. 5.34a-c. Patient after SAH with a basilar tip aneurysm seen on CTA in an outside hospital. a Initial DSA did show vasospasm of the PI segment and the superior cerebellar artery on both sides. In addition, some irregularity at the tip of the basilar artery was noted but no real aneurysm, b Repeated DSA 2 months later showed a small basilar tip aneurysm suitable for endovascular treatment, c The patient was scheduled for embolization 10 days later but the aneurysm again was not visible. The patient was referred to surgery... 

Fig. 5.79a,b. Conventional angiography before and after selective obliteration of a basilar stem aneurysm located in the distal third of the vessel proximal to the origin of the superior cerebellar artery... 

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