Title:Establishment of a Rat Model of Infraorbital Neuroinflammation Under
CT Guidance
Volume: 20
Issue: 2
Author(s): Chen Zeng, Chuan Zhang, Ruhui Xiao, Yehan Li, Xing Luo, Hao Deng and Hanfeng Yang*
Affiliation:
- Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, 637000, China
- Department
of Radiology, The First Affiliated Hospital of Jinan University, Guangzhou, 510630, China
Keywords:
Animal model, infraorbital nerve, pain, rat, transmission electron microscopy, trigeminal neuralgia.
Abstract:
Introduction: The aim is to establish a rat model of infraorbital neuroinflammation with
less trauma, stable pain, and a long duration of pain. The pathogenesis of TN is not fully clear.
There are various models of TN in rats with different disadvantages, such as damaging the surrounding
structures and inaccuracy of location for infraorbital nerve (ION). We aim to establish a
rat model of infraorbital neuroinflammation with minimal trauma, a simple operation, and accurate
positioning under CT guidance to help us study the pathogenesis of trigeminal neuralgia.
Methods: Thirty-six adult male Sprague Dawley rats (180-220 g) were randomly divided into 2
groups and injected with talc suspension or saline through the infraorbital foramen (IOF) under CT
guidance. Mechanical thresholds were measured in the right ION innervation region of 24 rats over
12 postoperative weeks. At 4 weeks, 8 weeks, and 12 weeks after the operation, the inflammatory
involvement of the surgical area was evaluated by MRI, and neuropathy was observed using a
transmission electron microscope (TEM).
Results: The talc group had a significant decrease in the mechanical threshold at 3 days after surgery
that continued until 12 weeks post-operation, and the talc group had a significantly lower mechanical
threshold than the saline group 10 weeks post-operation. The talc group had significantly
impaired trigeminal nerve (TGN) myelin after 8 weeks post-operation.
Conclusion: The rat model of infraorbital neuroinflammation established by CT-guided injection
of talc into the IOF is a simple operation that results in less trauma, stable pain, and a long duration
of pain. Moreover, infraorbital neuroinflammation in peripheral branches of the TGN can cause
demyelination of the TGN in the intracranial segment.
