Variants in the structure and topography of the superior margin of the epidural space of the human spinal cord

A common yet undescribed MRI finding in newborns: posterior epidural space edema of the cervical and upper thoracic spine

PURPOSE

Posterior spinal epidural space (PSES) is a fat-containing space. We noted numerous spinal MRIs demonstrating T2-hyperintense thickening of the cervical/thoracic PSES in early newborns, resembling epidural edema. Our aim is to describe the appearance/frequency of this finding and explore any associations with delivery.

METHODS

Retrospectively, 202 spinal/cranial MRIs, belonging to newborns within the first 2 weeks of life, were evaluated using sagittal fat-suppressed T2, T1-FLAIR, and STIR. Exclusion criteria were motion, incomplete spine imaging, lack of sagittal T2/STIR, and inadequate clinical data. Ninety-three patients were included in the final analysis. We reviewed all cases for T2 hyperintense thickened PSES and, if present, accompanying abnormal T1 signal. The spinal canal and PSES thickness were measured. Clinical and demographic data were collected. Follow-up exams were evaluated, if available. Cases with thickened PSES and without were compared.

RESULTS

T2-hyperintense thickened PSES was present in 60/93 (64.5%). Mean PSES thickness was 2.3 mm (0.7-4.6). The mean PSES thickness/spinal canal diameter ratio was 0.2 (0.1-0.5). No cord compression was identified. One had a hyperintense T1 PSES signal, compatible with epidural hemorrhage. No difference was found between those with thickened PSES and without, regarding sex, gestational age, birth weight, birth method, difficult delivery, fetal position, or neurologic status (p>0.05). Follow-up imaging was available in 10, with complete resolution of T2 hyperintense PSES thickening.

CONCLUSION

T2 hyperintense PSES thickening is common in imaged newborns and reversible at follow-up. No significant neurologic outcomes were found related to its presence; thus, follow-up does not appear necessary.