Anatomical study of arterial arrangement of the spinal cord in Syrian hamsters (Mesocricetus auratus)

This study aimed to investigate the arterial arrangement of the spinal cord in Syrian hamsters, and to identify differences and similarities to humans and experimental animals that are mostly used as models in studies into ischemic spinal cord injuries. This observational anatomical study was conducted on 20 adult Syrian hamsters using dissection and corrosion casting technique. The general anatomy of the arterial blood supply of spinal cord was obtained and noted as follows: (1) high variability in the level of the origin of right and left vertebral arteries, (2) the independent origin of dorsal intercostal arteries, (3) origin of lumbar arteries as a common trunk with right and left divisions, (4) presence of dorsal and ventral radicular branches in both sides of the cervical spinal cord with almost the same frequency, (5) greater presence of ventral and dorsal radicular branches in the left side of the thoracolumbar spinal cord, (6) two dorsal spinal arteries originating from the posterior inferior cerebellar arteries and extending to the caudal end of the thoracic spinal cord, (7) continuous ventral spinal artery originating from both vertebral arteries and extending to the conus medularis, and (8) presence of the artery of Adamkiewicz in the thoracic region of the spinal cord. From comparative anatomy viewpoints, the arteries supplying the spinal cord of Syrian hamsters exhibit many similarities with humans, laboratory rodents, and rabbits in many aspects compared to dogs, cats, and pigs. Overall, Syrian hamsters can be used as a proposed model in experimental studies of the spinal cord ischemia.

Integration of multiple prognostic predictors in a porcine spinal cord injury model: A further step closer to reality

Introduction

Spinal cord injury (SCI) is a devastating neurological disorder with an enormous impact on individual's life and society. A reliable and reproducible animal model of SCI is crucial to have a deeper understanding of SCI. We have developed a large-animal model of spinal cord compression injury (SCI) with integration of multiple prognostic factors that would have applications in humans.

Methods

Fourteen human-like sized pigs underwent compression at T8 by implantation of an inflatable balloon catheter. In addition to basic neurophysiological recording of somatosensory and motor evoked potentials, we introduced spine-to-spine evoked spinal cord potentials (SP-EPs) by direct stimulation and measured them just above and below the affected segment. A novel intraspinal pressure monitoring technique was utilized to measure the actual pressure on the cord. The gait and spinal MRI findings were assessed in each animal postoperatively to quantify the severity of injury.

Results

We found a strong negative correlation between the intensity of pressure applied to the spinal cord and the functional outcome (P < 0.0001). SP-EPs showed high sensitivity for real time monitoring of intraoperative cord damage. On MRI, the ratio of the high-intensity area to the cross-sectional of the cord was a good predictor of recovery (P < 0.0001).

Conclusion

Our balloon compression SCI model is reliable, predictable, and easy to implement. By integrating SP-EPs, cord pressure, and findings on MRI, we can build a real-time warning and prediction system for early detection of impending or iatrogenic SCI and improve outcomes.

Arterial Blood Supply to the Spinal Cord in Animal Models of Spinal Cord Injury. A Review

Animal models are used to examine the results of experimental spinal cord injury. Alterations in spinal cord blood supply caused by complex spinal cord injuries contribute significantly to the diversity and severity of the spinal cord damage, particularly ischemic changes. However, the literature has not completely clarified our knowledge of anatomy of the complex three-dimensional arterial system of the spinal cord in experimental animals, which can impede the translation of experimental results to human clinical applications. As the literary sources dealing with the spinal cord arterial blood supply in experimental animals are limited and scattered, the authors performed a review of the anatomy of the arterial blood supply to the spinal cord in several experimental animals, including pigs, dogs, cats, rabbits, guinea pigs, rats, and mice and created a coherent format discussing the interspecies differences. This provides researchers with a valuable tool for the selection of the most suitable animal model for their experiments in the study of spinal cord ischemia and provides clinicians with a basis for the appropriate translation of research work to their clinical applications. Anat Rec, 300:2091-2106, 2017. © 2017 Wiley Periodicals, Inc.

Morphometry and Variability of the Brain Arterial Circle in Chinchilla (Chinchilla laniger, Molina)

Arterial circles of brains from 70 adult chinchillas were filled with synthetic latex. The arterial circle of the brain is formed as the result of vertebral arteries being merged into the basilar artery. Caudally, both vertebral arteries gave rise to the ventral spinal artery. The ventral spinal artery splits into tiny cerebellar vessels, the pontine and cochlear branches. Distally, the basilar artery ramified into two terminal branches that formed the arterial circle of brain, rostrally open in most cases (75%). The observed variability of the arterial circle of brain of chinchillas pertained to all elements of that circle. The greatest variability within the vessels of the circle of Willis in chinchillas was observed in 22 cases (31.4%) of internal ophthalmic arteries. In chinchillas, a trend toward slight variability within the arteries comprising the arterial circle of the brain was observed in 44 animals. This accounted for 62.8% of all cases. Only in three cases was the arterial circle of brain clearly symmetrical. At the same time, 23 animals (32.8%) revealed features of significant vascular variability within the brain base region. These consisted of disturbed geometry of the entire arterial circle, different levels of ramifications into individual arteries, as well as the number and diameter of arteries. No internal carotid arteries were observed in chinchillas apart from one atypical case in which the carotid artery extended unilaterally into the basilar artery. These investigations indicate on the significant variability of arterial circle in rodents. Anat Rec, 300:1472-1480, 2017. © 2017 Wiley Periodicals, Inc.