The cerebrospinal fluid (CSF) surrounds and protects the brain and spinal cord by being a clear, watery liquid. It also helps regulate blood pressure and flow in the brain. The cerebrospinal fluid normally stays within the brain's closed system of membranes and bones, but sometimes it leaks out through holes or tears. A cerebrospinal fluid leak, or CSF leak, is a condition that occurs when this fluid is leaking.
A CSF leak can be caused by various factors, such as:
Trauma or injury to the head or spine, such as a car accident, a fall, or a gunshot wound
Surgery or invasive procedures on the brain or spine, such as a lumbar puncture, a spinal tap, or a shunt placement
Congenital defects or malformations of the skull or spine, such as Chiari malformation, spina bifida, or meningocele
Increased pressure in the brain, such as from a brain tumor, hydrocephalus, or pseudotumor cerebri
Infections or inflammation of the brain or spine, such as meningitis, encephalitis, or epidural abscess
Degenerative or aging-related changes of the bones or membranes, such as osteoporosis, arthritis, or calcification
Typically, a CSF leak manifests as a clear, watery, and often salty drainage from the nose or ear, or dripping into the throat as a result of coughing, sneezing, straining, or bending over. Other symptoms of a CSF leak include:
Headache, especially when standing up or sitting down
Nausea, vomiting, or dizziness
Neck stiffness or pain
Hearing loss, ringing in the ears, or ear fullness
Vision changes, such as blurred vision, double vision, or sensitivity to light
Facial numbness, weakness, or paralysis
Difficulty swallowing, speaking, or breathing
Confusion, memory loss, or altered mental status
Fever, chills, or signs of infection
A CSF leak can be diagnosed by various tests, such as:
Physical examination, where the doctor may look for signs of fluid leakage, check the vital signs, and assess the neurological function
Lab tests, where the doctor may collect and analyze samples of the fluid, blood, or urine to check for the presence of CSF, glucose, protein, or infection
Imaging tests, where the doctor may use X-rays, CT scans, MRI scans, or nuclear medicine scans to look for the source and location of the leak, and to rule out other causes of the symptoms
Dye tests, where the doctor may inject a special dye into the CSF system and then use imaging tests to see if the dye leaks out
Pressure tests, where the doctor may measure the pressure of the CSF system using a device called a manometer
The treatment of a CSF leak depends on the cause, severity, and location of the leak, and may include:
Conservative measures, such as bed rest, hydration, pain relief, and antibiotics to prevent or treat infection
Medications, such as acetazolamide, caffeine, or steroids to reduce the pressure or production of CSF
Procedures, such as an epidural blood patch, where the doctor injects the patient’s own blood into the epidural space to seal the leak
Surgery, where the doctor repairs the hole or tear using various techniques, such as sutures, grafts, or glue
Shunts, where the doctor inserts a tube or device to divert the excess CSF to another part of the body, such as the abdomen or the heart
Some of the ways to prevent or reduce the risk of a CSF leak are:
Avoiding trauma or injury to the head or spine, such as wearing a seat belt, a helmet, or protective gear
Following the doctor’s instructions and precautions after surgery or invasive procedures on the brain or spine, such as avoiding lifting, bending, or straining
Seeking medical attention promptly if there are any signs or symptoms of a CSF leak, such as fluid leakage, headache, or infection
Managing the underlying conditions that may cause increased pressure in the brain, such as treating a brain tumor, hydrocephalus, or pseudotumor cerebri
Maintaining a healthy lifestyle, such as eating a balanced diet, exercising regularly, and quitting smoking
