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.
Spinal fluid leak or CSF leak occurs if the membrane which enclosed the spinal fluid around the central nervous system is punctured. The membrane is quite tough but it can be damaged during surgery for chronic back pain. CSF is the one that protects and insulates the brain from all kinds of harm.