Purdy Phillip D, White Charles L, Baer Donna L, Frawley William H, Reichard R Ross, Pride G Lee, Adams Christina, Miller Susan, Hladik Christa L, Yetkin Zerrin
Department of Radiology, Division of Neuroradiology, the University of Texas Southwestern Medical Center at Dallas 75390-8896, USA.
AJNR Am J Neuroradiol. 2004 Sep;25(8):1435-42.
Our previous model of spinal cord injury (SCI) included six dogs undergoing 30-minute compression with a balloon in the subarachnoid space. We determined whether various balloon sizes and compression times creates a gradation of injuries.
In 17 dogs (including our original six), angioplasty balloons 2, 4, or 7 mm in diameter (2 cm long) were inflated at T6 for 30, 120, or 240 minutes. T1- and T2-weighted, gadolinium-enhanced, and short-tau inversion recovery (STIR) MR images were obtained at 1.5 T. Spinal canal occlusion (SCO) was measured as balloon area-spinal cord area. Hematoxylin-eosin and beta amyloid precursor protein staining were performed to demonstrate hemorrhage and axonal injury, respectively. Injuries were scored as mild, moderate, or severe. Trends were assessed with one-way analysis of variance.
SCO was 12.5-20% for 2-mm balloons, 28-56% for 4 mm, and 62-82% for 7 mm. No abnormalities were seen with SCO <30%. T1- and T2-weighted images had the poorest diagnostic performance; STIR images were best for predicting hemorrhage and axonal injury. Hemorrhage was demonstrated more frequently than was axonal injury. SCO (P < .0001) and hemorrhage (P = .002) significantly increased with balloon size. Longer inflation times tended to increase injuries for a given size, but differences were not significant.
Compression injuries depended on the level of SCO. The compression times tested had less effect than the degree of compression. The value of 1.5-T MR imaging varied with the sequence and improved with contrast enhancement. STIR images showed SCIs not otherwise detected.
我们之前的脊髓损伤（SCI）模型包括六只狗，它们在蛛网膜下腔用球囊进行了30分钟的压迫。我们确定了不同的球囊大小和压迫时间是否会造成不同程度的损伤。
在17只狗（包括最初的6只）中，将直径为2、4或7毫米（长2厘米）的血管成形术球囊在T6处充气30、120或240分钟。在1.5T下获得T1加权、T2加权、钆增强和短tau反转恢复（STIR）磁共振图像。脊髓管闭塞（SCO）以球囊面积-脊髓面积来测量。分别进行苏木精-伊红染色和β淀粉样前体蛋白染色以显示出血和轴突损伤。损伤分为轻度、中度或重度。采用单因素方差分析评估趋势。
2毫米球囊的SCO为12.5%-20%，4毫米球囊为28%-56%，7毫米球囊为62%-82%。SCO<30%时未见异常。T1加权和T2加权图像的诊断性能最差；STIR图像最适合预测出血和轴突损伤。出血比轴突损伤更常见。SCO（P<.0001）和出血（P=.002）随球囊大小显著增加。对于给定大小的球囊，较长的充气时间往往会增加损伤，但差异不显著。
压迫性损伤取决于SCO的程度。所测试的压迫时间比压迫程度的影响小。1.5T磁共振成像的价值因序列而异，且通过对比增强有所改善。STIR图像显示了其他方法未检测到的脊髓损伤。
