Table 1 Summary of definition of high-intensity zones (HIZs) in the lumbar spine

Carragee et al.

Central intensity of high-intensity signal was within 10% of the CSF intensity.

Hancock et al.

High-intensity signal located in the substance of the posterior annulus fibrosus, which is brighter than the nucleus pulposus in T2-weighted images.

Takatalo et al.

High-intensity signal located in the substance of the posterior annulus fibrosus, which is brighter than the nucleus pulposus in T2-weighted images

Wang et al.

High-intensity signal located in the substance of the posterior annulus fibrosus, which is brighter than the nucleus pulposus in T2-weighted images.

Three-dimensional localization method was described as follows: (a) posterior annular HIZ signs on sagittal

T2-weighted MR images were distinguish; (b) target HIZ in the left, middle, or right part of the annulus fibrosus were located according to the relative position to mid-sagittal plane on scout view; and (c) a straight line was drawn across the midpoint of ventral edge and the midpoint of dorsal edge of the lumbar disc on sagittal view. The location of HIZs was confirmed in accordance with the relative position to the line and characterized as HIZs in superior, middle, or inferior annulus.

Liu et al.

High-intensity signal located in the substance of the posterior annulus fibrosus, which is brighter than the nucleus pulposus in T2-weighted images. The posterolateral lesions were also included. If HIZ was evident in more than one sagittal image, the largest lesion was selected.

Yang et al.

High-intensity signal located in the substance of the posterior annulus fibrosus, which is brighter than the nucleus pulposus in T2-weighted images.