Temporal evolution of spinal cord infarction in an in vivo experimental study of canine models characterized by diffusion‐weighted imaging

Abstract

To determine the temporal evolution of diffusion abnormalities of in vivo experimental spinal cord infarction. Guided by a digital subtract angiography (DSA) monitor, an agent of 1:1 match of lipiodol and diatrizoate meglumine was injected into bilateral T9-11 intercostal arteries of six dogs to embolize the spinal branches of intercostal arteries and establish the canine spinal cord infarction models. The progression of experimental spinal cord infarction was followed by dynamic MRI, including diffusion-weighted imaging (DWI) on a 1.5 Tesla MR system from one hour to 168 hours postembolization. Apparent diffusion coefficient (ADC) values were calculated and analyzed. At the end of the MRI experiments, the spinal cords of the animals were fixed for histology. A total of six experimental models were successfully established. In all cases, DWI images showed slight hyperintensity within one hour postembolization, whereas only four cases presented slight hyperintensity on T2-weighted images. ADC values of spinal cord infarction lesions decreased rapidly at early stage (several hours to 24 hours) and then increased gradually. The temporal evolution of diffusion abnormality of experimental spinal cord infarction may help us better understand various DWI signals in the process of spinal cord infarction.