Effect of spinal cord compression on local vascular blood flow and perfusion capacity by Alshareef M, Krishna V, Ferdous J, Aishareef A, Kindy M, Kolachalama VB, et al.

BACKGROUND: Different degrees of blood flow/vascular compromise occur with anterior, posterior, or circumferential spinal cord compression/spinal cord injury (SCI). SCI is also divided into primary and secondary injury. Primary SCI refers to the original neurological damage to tissues, whereas secondary injury reflects interruption of normal blood flow leading to further inflammatory response/other local changes which contribute to additional neurological injury. METHODS: The authors developed a quantitative “3-D finite element fluid structure interaction model” of spinal cord blood flow to better document the mechanisms of secondary ischemic damage occurring in the spinal cord anteriorly, posteriorly, or circumferentially. This included assessment of the anterior spinal artery (ASA) and five arterial branches (L1, L2, L3, R1, R2), but excluded the microvasculature. RESULTS: Different locations of cord compression resulted in alternative patterns of spinal cord ischemia. Anterior spinal artery (ASA) flow was substantially reduced by direct anterior compression, but resulted in the least vascular compromise. Alternatively, posterior compression resulted in a significant and critical reduction of distal ASA blood flow and, therefore, correlated with the greatest susceptibility to acute ischemia. Counterintuitively, they concluded “at equivalent degrees of dural occlusion, the loss of branch blood flow under anterior posterior compression was intermediate to predictions for purely posterior or anterior loading.” CONCLUSION: Utilizing a computational three-dimensional model, Alshareef et al. observed that anterior cervical cord compression resulted in the least severe compromise of ASA blood flow to the spinal cord, whereas posterior cord compression/SCI maximally reduced distal ASA blood flow potentiating acute ischemia. Therefore, the latter warranted the earliest surgical intervention.