Results from the subjective and objective analyses comparing IMAR and wFBP

Neuroradiologist EvaluationwFBP (Median)IMAR (Median)TestP Value
Subjective
    Overall soft-tissue visualization scorea1 ± 1.503 ± 1.27WSR<.001
        Cervical (n = 21)2 ± 1.544 ± 1.06WSR.001
        Thoracic (n = 8)NAbNAb
        Lumbar (n = 39)1 ± 1.243 ± 1.15WSR<.001
    Soft-tissue structure with worst artifacts, visualization scorea0 ± 1.343 ± 1.19WSR<.001
        Cervical (n = 21)1 ± 1.533 ± 1.20WSR.001
        Thoracic (n = 8)NAbNAb
        Lumbar (n = 39)0 ± 1.182 ± 1.04WSR<.001
    Bone (cortex) visualization score5 ± 0.495 ± 0.87WSR.02
        Cervical (n = 21)5 ± 0.365 ± 0.30WSR.16
        Thoracic (n = 8)NAbNAb
        Lumbar (n = 39)5 ± 0.545 ± 0.16WSR<.001
Objective
    Vertebral body cortical obscuration (in degrees)7 ± 173 ± 12PTT<.001
    Vertebral body cortical obscuration, when present (n = 15) (degrees)34 ± 2213 ± 24PTT<.001
    Length of flame artifacts (mm)29 ± 1811 ± 7PTT<.001
  • Note:—NA indicates not applicable; PTT, 2-tailed paired t test; WSR, Wilcoxon signed rank test.

  • a Structures evaluated in the region of metal fixation hardware included the central canal, spinal cord, neural foramina, and prevertebral soft tissues.

  • b A subgroup analysis of thoracic spine cases was not performed due to the few cases in this group.