Oral Posters: Thoraco-lumbar Degenerative

Presented by: Y.J. Jin - View Audio/Video Presentation (Members Only)

Author(s):

Y.J. Jin(1)

(1) Seoul Paik Hospital, College of Medicine, Inje University, Department of Neurosurgery, Seoul, Korea, Republic of

Abstract

The aim of this study is to illustrate the significance in the extradural and periannular enhancements on fat suppressed magnetic resonance (MR) imaging and relationship with clinical outcome in patients with radicular pain or midline back pain. The inflammatory change is concerned with peripheral venous dilation and neoangiogenesis in the lesion site. The change is easily detectable on the enhanced and fat-suppressed MR images. In a prospective study, 1056 patients were enrolled performing gadolinium-enhanced lumbar spine MRI studies with fat suppression. 607 patients met the inclusion criteria. The patients were divided into three groups such as midline back pain (n=151), unilateral suprailiac and upper buttock pain (n=117), lower buttock or leg pain (n=339). Provocative epidural injections via transforaminal approach to patients with lateralizing symptom and interlaminar approach to those with midline symptom were performed according to the enhancement sites. Pain distribution, patterns and locations of extradural and periannular enhancement adjacent to annular tears on MRI were assessed.
In midline back pain group, enhancement was prominent in the retrocorporeal subligamentous fibrovascular tissue and ventral epidural venous plexus (74% in patients without protrusion, 100% with protrusion) and then, central circumferential tear with lake or slit shape (56% in patients without protrusion, 8% with protrusion). Favorable outcome (over 50% pain relief) was obtained in 95% of patients. In suprailiac and upper buttock pain group, ipsilateral foraminal and extraforaminal periannular enhancement (100%) was predominant in patients without protrusion. Mostly, they occurred near HIZ on T2-WI. 50% of patients with protrusion had ipsilateral enhancement in the ventral epidural and subarticular area. All patients showed favorable response. In lower buttock or leg pain group, ipsilateral foraminal and extraforaminal periannular enhancement were predominant in 70% of patients without protrusion, 98%/100% of those with foraminal/extraforaminal protrusion. Ipsilateral ventral epidural venous enhancement was detected in 100% of patients with mild protrusion or extruded disc. Favorable outcome occurred in 91% without protrusion, 92% with mild protrusion and extrusion, 95% with foraminal disc, and 100% with extraforaminal disc.
Enhancement site around disc space may be relevant in the diagnosis of symptomatic chemical radicular pain and midline back pain. This will help interventionists to reduce the amount of injectate via a target-specific approach.