Lateral Spinal Artery Research Articles

Vascular Microanatomy of the Pontomedullary Junction, Posterior Inferior Cerebellar Arteries, and the Lateral Spinal Arteries

This study of 25 brains at the pontomedullary junction defined the different possible origins of the perforating arteries and lateral spinal arteries in relation to the posterior inferior cerebellar arteries (PICAs). - If the PICA emerges from the common trunk of the AICA-PICA coming from the basilar artery, it never gives perforating arteries or a lateral spinal artery on the lateral surface of the brain stem but supplies blood to a part of the ipsilateral cerebellar hemisphere. - If the PICA arises extradurally at C1, it never gives perforating arteries for the lateral surface of the brain stem, but it gives pial branches for the posterior surface of the medulla oblongata and is always the origin of the lateral spinal artery. - If the PICA emerges in the intradural vertebral artery, it is the source of the perforating arteries for the lateral surface of the brain stem and of the blood supply of the ipsilateral cerebellum.

Developmental Anatomy of the Distal Vertebral Artery in Relationship to Variants of the Posterior and Lateral Spinal Arterial Systems

A certain number of anatomic variants involving the distal vertebral artery (VA) are explained by variations in size and connection of the lateral spinal artery (LSA). This study examined the possible role of another branch of the VA, the posterior spinal artery (PSA), in the development of similar vascular variations. Four types of variations in the distal VA, including the C1 and C2 origins of the posterior inferior cerebellar artery (PICA), the duplication of the distal VA, and the aberrant course of the distal VA, are illustrated by 9 angiographic observations. For each type of VA variant listed above, examples resulting from variations in size and connection of the LSA and PSA could be matched. Variation in size and connection of the PSA is at the origin of a set of anatomic variations of the distal VA similar, but not identical, to the vascular variants linked to the LSA.

Lateral spinal artery aneurysm associated with a posterior inferior cerebellar artery main trunk occlusion

347 Manuscript received May 8, 2005; accepted in final form January 18, 2006. Address reprint requests to: Hisashi Kubota, M.D., Department of Neurosurgery, Yamaguchi University School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505, Japan. email: hisakubo@yamaguchi-u.ac.jp. FIG. 1. Admission angiographic studies. A: Neither the PICA nor the aneurysm was clearly visible on the right VA angiogram. B: Right VA angiogram (left oblique view) showing a 4 3 4–mm aneurysm with a well-demarcated round shape (arrowhead) 25 days after admission. The PICA main trunk (arrow) is not visible. FIG. 2. A: Intraoperative view of the LSA aneurysm. B: Artist’s drawing in which the suction tip and dissector have been erased. The collateral vascular network on the posterolateral surface of the medulla oblongata supplied the blood flow to the distal PICA territory. a = aneurysm; b = LSA; c = PICA; d = occlusive PICA; e = VA; f = collateral artery. Spinal artery aneurysms are rare in intracranial lesions, and lateral spinal artery (LSA) aneurysms have been reported in only two cases.1 We describe the first case of an LSA aneurysm developing after posterior inferior cerebellar artery (PICA) occlusion. This 59-year-old woman was admitted to our hospital with sudden-onset severe headache and consciousness disturbance. A computerized tomography (CT) study revealed subarachnoid hemorrhage (SAH) in the posterior fossa, mostly around the medulla oblongata. Initial and subsequent angiographic studies demonstrated no vascular malformation (Fig. 1A). Fourteen days after admission, a new angiographic study showed a small aneurysm near the PICA, but its precise origin was not obvious. At 25 days, a fourth angiographic study revealed complete occlusion of the ipsilateral PICA, in which small collateral arteries were seen (Fig. 1B). During surgical exploration we found that the aneurysm was located on the LSA that contributed to the distal revascularization of the PICA (Fig. 2). After isolating the aneurysm, the lesion was excised. A ventriculoperitoneal shunt was placed to treat the hydrocephalus. Posttreatment, the patient’s disturbed consciousness gradually improved. The LSA arises from the PICA or vertebral artery (VA) and descends beside the spinal cord posterolaterally, entering into the posterior spinal artery (PSA).1,2 To our knowledge, there have been only a few reports of aneurysms of the LSA1 or of the PSA.3–5 If the VA or PICA is occluded, resulting in changing hemodynamic forces, the LSA occasionally plays an important role as a collateral artery. Although LSA aneurysms are rare, in cases involving posterior fossa SAH and an initially negative angiogram, one must persist with further angiography with particular attention to distal branches of the posterior circulation, like the LSA, which can harbor an aneurysm.

Aneurysms of the Lateral Spinal Artery: Report of Two Cases

Aneurysms of the Lateral Spinal Artery: Report of Two Cases

Aneurysms of the Lateral Spinal Artery: Report of Two Cases

Aneurysms of the Lateral Spinal Artery: Report of Two Cases

Lumbosacral anterolateral spinal arteries and brief review of "accessory" longitudinal arteries of the spinal cord.

The lumbosacral anterolateral spinal arteries (LALSA) were studied in 14 injected lumbosacral spinal cords. Contrary to many previously published opinions, which claimed that virtually all of the formerly described "accessory" longitudinal arteries of the vasa corona, were too inconstant to be of significance, the LALSA in this series were reliably present bilaterally and averaged a length of 8.4 cm. They ran in the acute angles formed by the emergence of the fascicles of the lumbosacral anterior spinal nerve roots and in this position, served as the origin for most of the proximal radicular arteries that supply the cranial half of the motor roots of the cauda equina. A review of the literature and analysis of other accessory longitudinal spinal arteries revealed that two other pairs of accessory spinal vessels, the lateral cervical spinal arteries (LCSA) and the lateral spinal arterial axes (LSA), have a demonstrable functional role and were sufficiently constant, along with the LALSA, to warrant inclusion in detailed descriptions of human spinal cord vasculature.

Anterior spinal arteryをmain feederとするanterior medullo-spinal junctionに局在するAVMのsurgical management

This 12-year-old boy suffered from a progressive gait disturbance. MRI and CT scan displayed a large arteriovenous malformation (AVM) located at the anterior medullo-spinal junction. The main feeder was the left anterior spinal artery. This was fed also by bilateral lateral spinal arteries originating from the vertebral artery and bilateral radicular arteries at the C3 level. Transoral feeder clipping of the anterior spinal artery was successfully performed. Several technical problems were overcome: prevention of liquorrhea using bone graft, abdominal fatty tissue and spinal drainage, selection of an appropriate clip with a small head, monitoring tolerance of occlusion of the anterior spinal artery with the spinal evoked potentials and with confirmation of respiratory function and movement of the four extremities under reduction of the depth of anesthesia. The patient recovered from the intervention completely.Six months later the patient underwent a feeder clipping of the lateral spinal artery and radicular artery on the left side using the monitoring method mentioned above. The patient endured the operation without any new deficits. Then left hemiplegia appeared two weeks later and three weeks after that the patient expired due to an intramedullary hemorrhage at the site of AVM.

The lateral spinal artery of the upper cervical spinal cord. Anatomy, normal variations, and angiographic aspects.

The lateral spinal artery corresponds to the most rostral extent of the posterolateral arterial axis of the spinal cord. It supplies the posterior and lateral aspects of the spinal cord, and courses anterior to the posterior roots of the upper cervical spinal nerves (C-1 to C-4), and posterior to the dentate ligament. The lateral spinal artery anastomoses rostrally with the branches of the posterior inferior cerebellar artery (PICA) at the restiform body and laterally with the extraspinal arteries at the emergence of each nerve. It may originate either from the vertebral artery or from the PICA lateral to the medulla. Certain variations will cause an unusual but normal enlargement of the vessel in a specific portion of its course; these variations include vertebral artery duplication, a C-1 or C-2 vertebral origin of the PICA, a C-1 or C-2 occipital origin of the PICA, and an intradural course of the vertebral artery at C-2. Knowledge of these variations in the arterial supply to the area allows for an understanding of the different anatomic peculiarities present and their angiographic importance.

PATHOGENESIS OF MYELOPATHY IN CERVICAL SPONDYLOSIS

A new explanation is offered for the pathogenesis of the myelopathy observed with cervical spondylosis. It is proposed that the root-sleeve fibrosis associated with the degenerative changes of the zygapophyseal and intervertebral joints can cause spasm of the lateral spinal arteries and their branches to the pial anastomoses. The spasm may originate either from direct stretching and kinking of these arteries during movement at the joints or may be mediated reflexly. The resultant intermittent cervical-cord ischæmia and loss of vascular autoregulation superimposed on a cord already compromised by external compression lead to a progressive myelopathy. This hypothesis assigns a major role to the degenerative changes compressing the cervical cord, but it is also compatible with the paradox that cervical cords with an ischæmic myelopathy do not show unequivocal histological evidence of vascular disease.

FOCAL LESIONS OF THE SPINAL CORD DUE TO VASCULAR DISEASE

No consideration of vascular disease of the spinal cord can be complete without a survey of its blood supply. The origin of the anterior and posterior spinal arteries from the vertebrals occurs at an acute angle just prior to their fusion to form the basilar artery. The anterior spinal arteries join into a common branch within a short distance of their origin and descend along the anterior surface of the cord to about the fifth cervical segment, where they are augmented by lateral branches from the deep cervical, intercostal, lumbar and sacral vessels (fig. 1). The posterior vessels do not unite, but descend along the dorsal surface of the spinal cord, situated on either side of the dorsolateral sulcus. They, too, are replaced by similar branches from the lateral spinal arteries. The deep cervical, intercostal, lumbar and sacral vessels are derived directly from the posterior wall of the aorta (fig.