Vertebral aneurysm

Fig. 5.23. a,b 3D CTA of bilateral MCA aneurysm and a small vertebral aneurysm, c-e DSA (ap view), aneurysmog-raphy and 3D CTA of a large MCA aneurysm demonstrating that one major MCA branch is originating very close to the neck of the aneurysm. f,g Fusiform MCA aneurysm 3D CTA and DSA match perfectly, h-j Broad-based basilar artery aneurysm encroaching both PI segments demonstrated on 3D CTA as well as on DSA. k-m Ruptured Pcom aneurysm (arrow)... 

Fig. 5.25a,b. Flair sequence demonstrating blood in the subarachnoid space around the brain stem and predominantly on the occipital surface and in the ventricles as well as acute hydrocephalus after rupture of a left vertebral aneurysm... 

Fig. 5.35a,b. Giant vertebral aneurysm in a 9-year-old boy with nausea and vomiting due to brain stem compression. a DSA ap view, b Axial contrast-enhanced CCT)... 

Fig. 5.37. a DWI with silent small infarct of the PICA after embolization of a left vertebral aneurysm. b,c DWI showing small acute cerebral infarctions in the territory of the MCA after embolization of an unruptured right paraophthahnic aneurysm the patient had no neurological symptoms... 

Fig. 5.71a-c. Broad based vertebral aneurysm at the origin of the PICA before and after stent placement and implantation of platinum coils... 

Fig. 5.72a,b. Small vertebral aneurysm before and after endovascular treatment... 

Fig. 5.73. a Very small ruptured vertebral aneurysm. b,d Two microstents (INX, Medtronic) were placed in front of the aneurysm, c Immediately, contrast stasis in the aneurysm was noted. Repeated DSA 10 days and 7 months (e) after intervention revealed complete aneurysm obliteration... 

In contrast to vertebral aneurysms located at the origin of the PICA, real PICA aneurysms are located either proximally or distally at the PICA itself Endovascular therapy with preservation of the parent artery... 

Vertebral arteries vary in size and symmetry, where mostly the left vertebral artery is the dominant one. The coincidence of vertebral fenestrations and aneurysms is well known. The anterior spinal artery receives tiny vessels from the vertebral arteries which are physiologically not depicted by MRA due to their size. The posterior inferior cerebellar artery (PICA) as the largest, most important and most variable cerebellar artery however, under normal conditions it is constantly depictable with TOF and CE-MRA. 

Penetrating and non-penetrating neck injuries are more likely to damage the carotid than the better protected vertebral artery. The vertebral artery appears to be more vulnerable to rotational and hyperextension injuries of the neck, particularly at the level of the atlas and axis. Laceration, dissection and intimal tears may be complicated by thrombosis and then embolism and, therefore, ischemic stroke at the time of the injury or some days or even weeks after the injury. Later stroke may be a consequence of the formation of a traumatic aneurysm, arteriovenous fistula or a fistula between the carotid and vertebral arteries (Davis and Zimmerman 1983). 

Embolism from thrombus within the cavity of an aneurysm is rare and is difficult to prove in cases where there maybe other potential sources of embolization. Intracranial aneurysms more commonly present with rupture and subarachnoid hemorrhage, whereas internal carotid artery aneurysms tend to cause pressure symptoms including a pulsatile and sometimes painful mass in the neck or pharynx, ipsilateral Horner s syndrome or compression of the lower cranial nerves. Extracranial vertebral artery aneurysms may cause pain in the neck and arm, a mass, spinal cord compression and upper limb ischemia (Catala et al. 1993). 

A systematic review of all prospective studies of the risks associated with spinal manipulation included five primary investigations (150). The most valid studies suggested that about half of all patients who see a chiropractor will have adverse effects, which are usually mild and transient. No reliable data about serious adverse events were uncovered. However, a review of recent case reports has shown that spinal manipulation was associated with several serious adverse effects, including dissection of the vertebral and internal carotid arteries, resulting in strokes and at least one death (151). Other instances relate to epidural hematoma, intracranial aneurysm, cauda equina syndrome, contusion of the spinal cord, myelopathy, radiculopathy, and palsy of the long thoracic nerve. 

Mas JL, Henin D, Bousser MG, Chain F, Hauw JJ. Dissecting aneurysm of the vertebral artery and cervical manipulation a case report with autopsy. Neurology 1989 39(4) 512-15. 

Suxamethonium-induced fasciculation or increased muscle tone can be dangerous in patients with fractures or dislocations (especially vertebral, when the drug is relatively contraindicated), in patients with open-eye injuries or after the eyeball is opened surgically, when an increase in abdominal pressure must be avoided (pheochromocytoma, aortic aneurysm, full stomach, ileus), and in patients in whom a rise in arterial pressure may be catastrophic (cerebral aneurysm, raised intracranial pressure). Prolonged paralysis, occasionally lasting hours, is a risk if the patient is, or has been, taking certain drugs. 

Most arterial aneurysms arise at the bifurcation of major arteries, and this is also true for the intracranial location. Around 85% of all intracranial aneurysms originate from the anterior circulation. The most common location (30%-35%) is the anterior communicating artery (Acorn). However, many of these so-called Acorn aneurysms do have their origin at the A1/A2 junction of the anterior cerebral artery and do not involve the anterior communicating artery. Internal carotid and posterior communicating artery aneurysms account for 30% and middle cerebral artery (MCA) bifurcation aneurysms for 20%. Around 15% of intracranial aneurysms arise at the vertebrobasilar circulation. Half of them develop at the basilar tip (with various degrees of involvement of the PI segments) and the other 50% from other posterior fossa vessels. Aneurysms of the anterior inferior cerebellar artery (AICA) and vertebral artery (VA) aneurysms without involvement of the VA-PICA junction or the vertebrobasilar site are extremely rare. 

Various nondetachable balloons are available for temporary vessel occlusion, angioplasty for vasospasm therapy or remodelling techniques for broad based aneurysms. Larger vessels like the carotid or vertebral artery can be occluded with a double lumen balloon catheter, i.e. Meditech (Cook). For intracranial angioplasty and remodeling smaller, more flexible balloons, like the Hyperglide (MTI), Eclipse (Balt), or the Copernic (Balt) are required. Additionally to these balloons tbe Hyperform microballoon (MTI) can be used for remodelling technique. 

Aneurysms of the vertebral artery leading to SAH are located at the V4 segment. Dissecting aneurysms are more frequent in this location than non-dis-... 

Fig. 5.80. a PA view. Giant vertebral artery aneurysm in a 9-year-old boy presenting with dizziness, vomiting and nausea, b Lateral view. Endovascular occlusion of the left vertebral artery was performed distal to the PICA using one GDC-Vortx-Coil. c Injection into the contralateral vertebral artery revealed no retrograde filling of the aneurysm, d-f CT before (d) and 6 months after (e,f) vessel occlusion demonstrated complete retraction of the aneurysm... 

Albuquerque PC, Fiorella DJ, Han PP, Deshmukh VR, Kim LJ, McDougall CG (2005) Endovascular management of intracranial vertebral artery dissecting aneurysms. Neu-rosurg Focus 18(2) E3... 

Hecht ST, Horton JA, Yonas H (1991) Growth of a thrombosed giant vertebral artery aneurysm after parent artery occlusion. AJNR Am J Neuroradiol 12 449-451... 

Horowitz MB, Levy El, Koebbe CJ, Jungreis CC (2001) Transluminal stent-assisted coil embolization of a vertebral confluence aneurysm technique report. Surg Neurol 55 291-296... 

Lanzino G, Wakhloo AK, Fessler RD, Hartney ML, Guter-man LR, Hopkins LN (1999b) Efficacy and current limitations of intravascular stents for intracranial internal carotid, vertebral, and basilar artery aneurysms. J Neurosurg 91 538-546... 

Lownie SP, Pelz DM, Fox AJ (2000) Endovascular therapy of a large vertebral artery aneurysm using stent and coils. Can J Neurol Sci 27 162-165... 

Neurosurgery 40 651-662 discussion 662-663 Schievink WI (2001) Spontaneous dissection of the carotid and vertebral arteries. N Engl J Med 344 898-906 Schievink WI, Wijdicks EF, Piepgras DG, Chu CP, O Fallon WM, Whisnant JP (1995) The poor prognosis of ruptured intracranial aneurysms of the posterior circulation. J Neurosurg 82 791-795... 

Fig. 23.4. Modified classification of thoracic and abdominal aortic aneurysms by Crawford. Type I distal of the left subclavian artery as far as the renal arteries type II distal of the left subclavian artery, extending below the renal arteries type III from the sixth thoracic vertebral body, extending below the re-...

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