Intradural lumbar disc herniation detected by 3D CISS MRI

Abstract

A 73-year-old man who presented with right lumbosciatic pain underwent a neurosurgical operation for a voluminous L2-L3 disc herniation, seen on conventional MRI images. No disc herniation was identified in the epidural space during the surgery. Just after the operation, the patient started to present pain in the left L3 territory and was not able to walk any more. A second MRI including three-dimensional (3D) high-resolution constructive interference in steady state (CISS) sequence showed that the voluminous L2-L3 disc split the posterior longitudinal ligament and the anterior dura mater, extended intradurally and compressed the cauda equina to the right. The patient underwent a second surgery, which permitted to cure the symptoms. 3D high-resolution CISS should be considered to accurately depict intradural disc herniation in order to optimally guide the surgical approach.

Keywords: neuroimaging; neurosurgery; radiology.

Figure 1

Intradural disc herniation and anatomical relations on 2D T2 spin-echo and 3D CISS sequences. Compared with standard 2D T2 spin-echo (first column), 3D high-resolution CISS MRI (second column) demonstrated that the L2–L3 disc herniation split the PLL (line A on coronal plane) and the anterior dura mater (line B on sagittal plane). The large paramedian left-sided disc extrusion entered into the thecal sac (line C on axial plane). It impinged on the left L3 nerve root and compressed the rest of the cauda equina to the right, with a typical ‘hawk-beak’ appearance (line C on axial plane). CISS, constructive interference in steady state; PLL, posterior longitudinal ligament; SE, spin-echo; 3D, three-dimensional; 2D, two-dimensional.