Renal Pelvis Opacification on Postmyelography Computed Tomography as an Indicator for Cerebrospinal Fluid Loss in Spontaneous Intracranial Hypotension.

Increased renal pelvis opacification on postmyelography CT was observed in SIH patients, even in the absence of a CSF leak or a CSF venous fistula, when compared to non-SIH patients. Although the provenance of early renal opacification in SLEC (-) SIH patients remains unclear, our results suggest that it may be a surrogate for increased spinal CSF resorption via spinal arachnoid granulations and along spinal nerve sheaths occult to direct imaging.