Readout-segmented diffusion tensor imaging for assessing sciatic nerve invasion by soft tissue tumor

Abstract

There are few publications regarding feasibility of readout-segmented diffusion tensor imaging (rsDTI) in assessing nerve invasion by soft tissue tumor. 64 patients with soft tissue mass in upper leg suspected of sciatic nerve invasion underwent rsDTI. Nerve invasion was confirmed in 28 cases by operation or electromyogram. The sciatic nerve was better depicted with diffusion weighted map versus b = 0 map of rsDTI. Inter-reader agreement in using rsDTI to rate nerve invasion was excellent. Sensitivity and specificity of rsDTI in identifying nerve invasion were 93% (26/28) and 92% (33/36) respectively. Apparent diffusion coefficient (ADC) was significantly higher in invaded nerves versus normal nerves (1.45 ± 0.67 × 10− 3mm2/s vs. 1.39 ± 0.46 × 10− 3mm2/s, P༜0.05). DTI derived FA was significantly lower in invaded nerves versus normal nerves (0.22 ± 0.11 vs. 0.37 ± 0.13, P༜0.05). Readout-segmented DTI was feasible in assessing sciatic nerve invasion by soft tissue tumor in selected patients.