Imaging in a patient with symptomatic CSF leakage. (a + b) MRI with intravenous contrast media displays enhancement of the meninges over the convexity and tentorium (arrow heads). A fluid collection separates the periosteal and the inner layer of the enhancing dura mater (arrows). (c + d) MRI with intrathecally applied gadolinium contrast agent. (c) Distribution of contrast agent in the subarachnoid space (solid arrow). (d) MRI depicts transforaminal contrast leakage as the diagnosis of meningeal tears in the left T2 nerve root (double arrow) with epidural distribution of contrast agent in the epidural space (triangle). (e + f) CT-guided blood patch. (e) Tuohy needle in the epidural space of T1/2 (curved arrows) used to inject a mixture of blood and iodine contrast agent into the epidural space (black triangles). (f) Epidural blood patch by means of a Tuohy needle (curved arrow) with epidural (triangle) and transforaminal (double arrow) distribution of the blood at the level of the T2 nerve root.