A patient's MRI with postural symptoms demonstrated:

• an extensive extradural fluid collection separating the dura from the bony spinal canal (curtain sign) in spinal MRI and

• signs of intracranial hypotension in cranial MRI (smooth enhancing pachymeningeal thickening, venous distension sign)

A post-myelogram CT demonstrates a cervical dural leak emitting contrast into the epidural space dorsally at the height of C1/2.

Important: It should be noted that an extradural contrast collection at C1/2 is often the case in patients with extensive epidural leakage because the leaked fluid can migrate significant distances and pool depending on patient position and anatomy, and it does not, in such cases, mean that the leak is definitely located at C1/2. This is known as the C1-C2 false localizing sign. In this case, however, the paucity of contrast in the epidural space elsewhere is more suggestive that this is actually the site of the leak. 

Therefore we concluded the diagnosis as cervical CSF leak leading to intracranial hypotension with postural symptoms.

The leak was later treated by a CT-guided blood patch at the C1/2 level. The patient did not show any postural symptoms from the day after treatment.