Infarct presenting with a combination of Wallenberg and posterior spinal artery syndromes

Anatomical Study of the Posterior Spinal Artery Branches to the Medulla Oblongata

BACKGROUND

The posterior spinal arteries (PSAs), branches of the intracranial segment of the vertebral artery or posterior inferior cerebellar artery, run bilaterally along the spinal cord and are integral to the blood supply primarily to the posterior one third of this structure. However, a less well-described distribution of the PSAs is their supply to the posterior medulla. The purpose of this study is to examine the medullary branches of the PSA anatomically.

METHODS

We conducted a cadaveric study to evaluate for branches of the PSA supplying the medulla oblongata.

RESULTS

All 14 sides had medullary branches arising from the PSAs. The average number of branches supplying the medulla oblongata on each side was 6. Most of these branches traveled laterally to anastomose with medullary branches arising from the anterior spinal artery. Additionally, lateral and ascending branches were noted.

CONCLUSIONS

Physicians who interpret imaging of the craniocervical junction, in particular arteriograms, should be aware of ascending medullary branches arising from the anterior spinal artery. Additionally, neurosurgeons operating this region must be careful in dissecting over the posterior medulla and manipulating the cerebellar tonsils, as in telovelar approaches to the fourth ventricle, in order to avoid iatrogenic injury to these vessels. Additionally, variable stroke patterns involving the vertebral artery or posterior inferior cerebellar artery might include ischemia to the medulla oblongata via PSA branches, and this anatomy should be kept in mind by interventionalists, radiologists, and neurologists alike.

Cervical Posterior Spinal Artery Syndrome Caused By Spontaneous Vertebral Artery Dissection: Two Case Reports and Literature Review

Herein, we described 2 patients with posterior spinal artery syndrome (PSAS) caused by vertebral artery dissection. The patients complained of sudden neck pain or walking instability. Neurological examination revealed sensory loss, muscle weakness, and sensory ataxia. Angiography showed double lumen sign or intimal flap in the vertebral artery. T2-weighted imaging and diffusion-weighted imaging of MRI showed a hyperintense lesion in the dorsal side of the cervical spinal cord at different times after onset. Both patients had good outcome after antiplatelet therapy and physiotherapy. A review of previously reported PSAS cases was also conducted in order to improve the understanding and awareness of this rare myelopathy.

Clinical core symptoms of posterior spinal artery ischemia

INTRODUCTION

Ischemia in the distribution of the posterior spinal artery is rare.

METHODS

Between 2004 and 2008 we observed 4 patients with posterior spinal artery ischemia (PSAI).

RESULTS

All patients had the expected loss of posterior column function but also suffered from motor deficits which were severe, and the leading symptom in 2 patients. Severe pain, bowel and bladder dysfunction were other concomitant symptoms. In 3 of 4 patients, a follow-up spinal MRI was needed to show the cord infarct together with vertebral body ischemia in 2 patients.

CONCLUSION

An acute onset of posterior column dysfunction with a variable degree of motor deficit and dorsalgia suggests PSAI.

Combination of infarctions in the posterior inferior cerebellar artery and anterior spinal artery territories

After an episode of vasodilator-induced systemic hypotension, a 75-year-old man developed ocular lateropulsion to the right, left-side-dominant quadriparesis, loss of superficial sensation below C4 dermatome level, and anuresis. Magnetic resonance imaging (MRI) showed infarcts in the right cerebellar hemisphere (posterior inferior cerebellar artery territory) and the upper cervical cord (anterior spinal artery territory); the combination of posterior inferior cerebellar artery (PICA) and anterior spinal artery (ASA) infarcts has not been reported previously. Angiography revealed severe stenosis in the bilateral vertebral arteries. Hemodynamic hypoperfusion of the stenotic vertebral arteries may cause this unusual combination.