Peripheral nerve injury

Diagnosis with MR imaging of denervated skeletal muscle - Experimental study in rats

Eiko Yamabe, Toshiyasu Nakamura, Koichi Oshio, Yoshito Kikuchi, Hiroyasu Ikegami, Yoshiaki Toyama

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

Purpose: To prospectively evaluate signal intensity change on T2-weighted magnetic resonance (MR) images and the time course of T2 values and T2 ratios after reinnervation in various nerve injury models in rats. Materials and Methods: Institutional animal use and care committee approval was obtained. Thirty male rats made up four groups of rats with an injured left posterior tibial nerve (irreversible neurotmesis, reversible neurotmesis, severe axonotmesis, or moderate axonotmesis) and one control group. There were six rats in each group. Signal intensity changes were seen in the gastrocnemius muscle on the T2-weighted MR images. T2 values were also measured in vivo with the Carr-Purcell-Meiboom-Gill method. Gait function was assessed by calculating the print length factor (PLF). T2 ratios and PLFs on the injured side were compared with those on the unaffected side. Ratios of specific acquisition points within groups were compared by using repeated-measures analysis of variance. Comparisons across the five groups at each acquisition point were performed by using one-way analysis of variance with Scheffe post hoc testing. P < .05 indicated a significant difference. Results: The more severe the nerve damage, the higher the signal intensity on T2-weighted MR images. There were significant differences in T2 ratios between the nerve injury groups and the control group (P < .05). Changes in T2 values and ratios depended on the degree of nerve injury. In the reversible neurotmesis group, T2 values and ratios began to decrease 28 days after surgery. In the severe and moderate axonotmesis groups, T2 values and ratios began to decrease 14 days after surgery. The starting point of functional recovery also depended on the degree of nerve injury. Conclusion: The degree and prognosis of nerve injury can be evaluated by observing changes in signal intensity on T2-weighted images and the time course of T2 values and ratios.

Original languageEnglish
Pages (from-to)409-417
Number of pages9
JournalRadiology
Volume247
Issue number2
DOIs
Publication statusPublished - 2008 May

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Nervous System Trauma
Peripheral Nerve Injuries
Skeletal Muscle
Magnetic Resonance Imaging
Wounds and Injuries
Magnetic Resonance Spectroscopy
Ambulatory Surgical Procedures
Analysis of Variance
Animal Care Committees
Tibial Nerve
Control Groups
Gait

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

Cite this

Peripheral nerve injury : Diagnosis with MR imaging of denervated skeletal muscle - Experimental study in rats. / Yamabe, Eiko; Nakamura, Toshiyasu; Oshio, Koichi; Kikuchi, Yoshito; Ikegami, Hiroyasu; Toyama, Yoshiaki.

In: Radiology, Vol. 247, No. 2, 05.2008, p. 409-417.

Research output: Contribution to journalArticle

Yamabe, Eiko ; Nakamura, Toshiyasu ; Oshio, Koichi ; Kikuchi, Yoshito ; Ikegami, Hiroyasu ; Toyama, Yoshiaki. / Peripheral nerve injury : Diagnosis with MR imaging of denervated skeletal muscle - Experimental study in rats. In: Radiology. 2008 ; Vol. 247, No. 2. pp. 409-417.
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