Epidurography contrast patterns with fluoroscopic guided lumbar transforaminal epidural injections:a prospective evaluation.

Contrast appeared ventrally and unilaterally in all injections. Dorsal flow occurred in 20% of these injections. No contrast flow crossed the midline. The observed contrast flow patterns should be studied clinically to determine whether they have any effect on clinical outcome. Intravascular injections were noted in 10% of cases.