Deadly brain drain: Fixing a leaky skull



BACKGROUND:  When the fluid which normally surrounds the brain begins to drip from the nose, it is referred to as a CSF leak. CSF stands for cerebrospinal fluid and is colorless, clear, and devoid of cells. CSF leaks occur when the brain lining and the bone separating the brain and the sinuses have been disturbed in some way. These kinds of leaks are often mistaken for sinus infections or allergy symptoms and so many patients go untreated. Unfortunately, since the barrier between the sinuses is compromised, these patients are at a high risk of infection, particularly meningitis. (Source:

TYPES:  While CSF leaks can result from accidental or surgical trauma where an injury causes cracks in the skull base or along the bone separating the brain and the sinuses, two other types of CSF leaks exist. 

  • Tumor-Related CSF Rhinorrhea: if an aggressive tumor or cancer invades the skull base, it can begin to erode the bone causing the barriers between the brain and sinuses to breakdown. The tumor then acts as the barrier and once removed, the patient begins to leak CSF.
  • Spontaneous CSF Rhinorrhea: when none of the other causes have occurred, the CSF leak is considered to be spontaneous. There is some evidence suggesting elevated intracranial pressure could be responsible for these leaks, but the exact cause is still unknown. (Source:

SYMPTOMS: It can be difficult to identify a CSF leak, but common signs of a leak include:

  • Clear, watery drainage usually from one side of the nose or one ear that increases when the head is tilted forward or strained.
  • Headaches, possibly accompanied by vision changes.
  • Unexplained hearing loss. (Source:

NEW TECHNOLOGY:  An endoscopic operation has become standard care for repairing CSF rhinorrhea because of its high success rate and low morbidity. Before the operation CT scans or MRI are taken to identify the area where fluid is leaking from. Then instruments are inserted into one of the nostrils. Sometimes fluorescein is injected so the defect becomes more visible under a certain filter of light. Once the defect is found, surgeons strip away the mucosa and graft material is placed to patch the injury. The material used for the graft can come from various places such as cartilage or abdominal fat, but generally where the graft material comes from has no bearing on the success of the operation. (Source: