RT Journal Article
SR Electronic
T1 Wallerian degeneration and inflammation in rat peripheral nerve detected by in vivo MR imaging.
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 741
OP 746
VO 10
IS 4
A1 D S Titelbaum
A1 J L Frazier
A1 R I Grossman
A1 P M Joseph
A1 L T Yu
A1 E A Kassab
A1 W F Hickey
A1 D LaRossa
A1 M J Brown
YR 1989
UL http://www.ajnr.org/content/10/4/741.abstract
AB To investigate the role of MR imaging in wallerian degeneration, a series of animal models of increasingly complex peripheral nerve injury were studied by in vivo MR. Proximal tibial nerves in brown Norway rats were either crushed, transected (neurotomy), or transected and grafted with Lewis rat (allograft) or brown Norway (isograft) donor nerves. The nerves distal to the site of injury were imaged at intervals of 0-54 days after surgery. Subsequent histologic analysis was obtained and correlated with MR findings. Crush injury, neurotomy, and nerve grafting all resulted in high signal intensity along the course of the nerve observed on long TR/TE sequences, corresponding to edema and myelin breakdown from wallerian degeneration. The abnormal signal intensity resolved by 30 days after crush injury and by 45-54 days after neurotomy, when the active changes of wallerian degeneration had subsided. These changes were not seen in sham-operated rats. Our findings suggest that MR is capable of identifying traumatic neuropathy in a peripheral nerve undergoing active wallerian degeneration. The severity of injury may be reflected by the corresponding duration of signal abnormality. With the present methods, MR did not distinguish inflammatory from simple posttraumatic neuropathy.