Kidney Stones, also known as renal calculi, are hard masses that separate urine from the urinary tract. These stones can occur anywhere in the urinary tract, including the kidneys, bladder, ureters and urethra.
This fluid is called the cerebrospinal fluid (CSF). When it leaks out, the pressure around the brain and spinal cord drops. Causes of leakage through the dura include: 1  Certain head, brain, or spinal surgeries.  Head injury.
Cerebrospinal Fluid (CSF) Leak. Cerebrospinal fluid (CSF) leak is a condition that occurs when there is a tear or hole in the membranes surrounding the brain or spinal cord, allowing the clear fluid that surrounds and cushions those organs to escape.