Value of T2-mapping in the diagnosis of non-compressive lumbar disc herniation: an experimental research

Abstract

Objective To study the value of T2-mapping in the diagnosis of non-compressive lumbar disc herniation. Methods Seven healthy adult Chinese piglets were scanned with T2-mapping under general anesthesia before injecting 2 ml homogenated nucleus pulposus into one side of intervertebral foramen at the level of L4-5, L5-6 and L6-S1 under CT guidance to induce nerve root inflammation. After 14 days of making model, the pigs were scanned again with T2-mapping used the same method to obtain T2 values of bilateral L5, L6, S1 spinal nerve roots. Finally the T2 values were compared with their contralateral normal nerve roots as well as the ipsilateral nerve root value obtained before induction of inflammation. Results The mean T2 values of bilateral nerve roots were (52.5±1.5) vs (52.1±1.3) respectively. There was no significant difference between the bilateral normal nerve roots (P>0.05) . After induction of inflammation, the mean T2 values of the contralateral nerve roots and the inflamed spinal nerve roots were (51.7±2.0) vs (63.2±2.1) respectively. There was statistical difference (P<0.05) . Pathological finding of the induced nerve root inflammation revealed that there were edema, infiltration of inflammatory cell and damage of the membrane structure. Conclusion The value of T2-mapping can reflect the characteristics of radiculitis caused by nucleus fluid leaked from adjacent disc. Key words: Magnetic resonance imaging; T2-mapping; T2 value; Non-compressive lumbar intervertebral disc herniation