Elevated intraspinal pressure drives edema progression after acute compression spinal cord injury in rabbits

Chaohua Yang; Tao He; Qing Wang; Gaoju Wang; Jingjin Ma; Zhiyu Chen; Qiaochu Li; Linbang Wang; Zhengxue Quan

doi:10.1016/j.expneurol.2022.114206

Elevated intraspinal pressure drives edema progression after acute compression spinal cord injury in rabbits

Exp Neurol. 2022 Nov:357:114206. doi: 10.1016/j.expneurol.2022.114206. Epub 2022 Aug 19.

Authors

Chaohua Yang¹, Tao He², Qing Wang³, Gaoju Wang³, Jingjin Ma⁴, Zhiyu Chen⁴, Qiaochu Li⁴, Linbang Wang⁴, Zhengxue Quan⁵

Affiliations

¹ Department of Orthopedic Surgery, The First Affiliated Hospital of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing 400016, China; Department of Orthopaedics, The Affiliated Hospital of Southwest Medical University, No.25 Taiping Street, Jiangyang District, Sichuan 646000, China; Orthopedic Laboratory of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing 400016, China. Electronic address: 14211330003@fudan.edu.cn.
² Department of Orthopedic Surgery, The First Affiliated Hospital of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing 400016, China; Orthopedic Laboratory of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing 400016, China; Department of Orthopaedic Trauma, Chongqing General Hospital, No.118 Xingguang Avenue, Liangjiang New District, Chongqing 40114, China.
³ Department of Orthopaedics, The Affiliated Hospital of Southwest Medical University, No.25 Taiping Street, Jiangyang District, Sichuan 646000, China.
⁴ Department of Orthopedic Surgery, The First Affiliated Hospital of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing 400016, China; Orthopedic Laboratory of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing 400016, China.
⁵ Department of Orthopedic Surgery, The First Affiliated Hospital of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing 400016, China; Orthopedic Laboratory of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing 400016, China. Electronic address: 201818@hospital.cqmu.edu.cn.

PMID: 35988698
DOI: 10.1016/j.expneurol.2022.114206

Abstract

Elevated intraspinal pressure (ISP) following traumatic spinal cord injury (tSCI) can be an important factor for secondary SCI that may result in greater tissue damage and functional deficits. Our present study aimed to investigate the dynamic changes in ISP after different degrees of acute compression SCI in rabbits with closed canals and explore its influence on spinal cord pathophysiology. Closed balloon compression injuries were induced with different inflated volumes (40 μl, 50 μl or no inflation) at the T7/8 level in rabbits. ISP was monitored by a SOPHYSA probe at the epicenter within 7 days post-SCI. Edema progression, spinal cord perfusion and damage severity were evaluated by serial multisequence MRI scans, somatosensory evoked potentials (SEPs) and behavioral scores. Histological and blood spinal cord barrier (BSCB) permeability results were subsequently analyzed. The results showed that the ISP waveforms comprised three peaks, significantly increased after tSCI, peaked at 72 h (21.86 ± 3.13 mmHg) in the moderate group or 48 h (31.71 ± 6.02 mmHg) in the severe group and exhibited "slow elevated and fast decreased" or "fast elevated and slow decreased" dynamic changes in both injured groups. Elevated ISP after injury was correlated with spinal cord perfusion and edema progression, leading to secondary lesion enlargement. The secondary damage aggravation can be visualized by diffusion tensor tractography (DTT). Moreover, the BSCB permeability was significantly increased at the epicenter and rostrocaudal segments at 72 h after SCI; by 14 days, notable permeability was still observed at the caudal segment in the severely injured rabbits. Our results suggest that the ISP of rabbits with closed canals increased after acute compression SCI and exhibited different dynamic change patterns in moderately and severely injured rabbits. Elevated ISP exacerbated spinal cord perfusion, drove edema progression and led to secondary lesion enlargement that was strongly associated with BSCB disruption. For severe tSCI, early intervention targeting elevated ISP may be an indispensable choice to rescue spinal cord function.

Keywords: Arterial spin labeling; Blood spinal cord barrier; Diffusion tensor tractography; Edema; Intraspinal pressure; Spinal cord injury.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Edema / diagnostic imaging
Edema / etiology
Evoked Potentials, Somatosensory
Magnetic Resonance Imaging
Rabbits
Spinal Cord / pathology
Spinal Cord Injuries* / complications
Spinal Cord Injuries* / diagnostic imaging
Spinal Cord Injuries* / pathology