Water-level sign: A vivid pictorial expression for a known neuroradiological phenomenon hitherto differently described

- Neuroradiologically heterogeneous architecture of fluid containing processes can present with a blood-fluid -, fluid-blood -, or fluid-fluid level.
- As a superordinate term “water-level sign” is proposed as the fluid components behave literally like a water-level.
- Chronic subdural hematoma, spinal subarachnoid hemorrhage, cerebral metastasis, or cystic pituitary process can reveal such a finding
- If such a finding can be identified, it can contribute to diagnosis and therapy.