Abstract No. 284: An intravertebral tumor model in rabbits created by transplantation of VX2 carcinoma via percutaneous puncture technique under CT guidance
The majority of current animal spinal tumor models are limited in rats, the size of which is too small to be studied for mechanism, efficacy and safety of the newly mini-invasive therapies such as percutaneous vertebroplasty. Although a very few literatures described the spinal tumor models in rabbits, but these models were established by surgical method, which may not be applicable for image-guided percutaneous puncture techniqueS(PPT). In the present study, we used CT-guided PPT to produce a predictable and reproducible spinal tumor model of rabbits and to investigate the onset of the paraplegia and histopathological findings of the animal model.
Materials and Methods
New Zealand white rabbits (n = 30) were transplanted with a piece of VX2 carcinoma in the lumbar vertebral body via CT guided PPT. Lower extremity motor function was assessed daily. MRI and CT scans were acquired on postoperative day (POD) 14,21,28 and at the onset of paraparesis. When vertebral tumors were detected on POD 21 and 28, one of the animals without paraparesis were sacrificed randomly and the vertebrae were dissected at different time point respectively. Hematoxylin and eosin cross sections were obtained. The other animals were sacrificed and the vertebrae were dissected at the onset of paraparesis. By the termination of the experiment on POD 90, the remaining animals without paraparesis were sacrificed and the histological studies were also performed.
Results
Vertebral tumors were developed in 27 rabbits. MRI scans revealed tumor in only one rabbit on POD 14. MRI and CT scans revealed tumors in 20 rabbits on POD 21, of whom 18 rabbits were no paraparesis. Tumors were detected in another 6 rabbits by MRI and CT scans on POD 28, including 5 rabbits without paraparesis. The mean time of the onset of paraparesis was 26.4±4.2 day(19 to 36). Histopathological examination confirmed tumor arising from the body and extending into the canal, with widespread osteolytic activity.
Conclusion
An intravertebral tumor model in rabbits was established via PPT under CT guidance. The method was easy and feasible with very high success rate to develop a vertebral tumor model. Vertebral tumors could be detected by CT and MRI from POD 21.
The First Affiliated Hospital of Suzhou University, SuZhou, China
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