CSF (spinal fluid) otorrhea is a condition in which spinal fluid drains from the ear. Patients with CSF otorrhea often have hearing loss in the affected ear.
There is a bone called the tegmen ("roof") that separates the ear from the brain, and in rare instances, the bone can become very thin and wear away. The brain then can sink down into the ear cavity. If the protective lining of the brain (dura) also wears away, spinal fluid will leak down into the ear.
Once spinal fluid gets in the ear, it causes hearing loss. It fluid can also drain down the Eustachain tube and out the nose, causing what's known as spinal fluid rhinorrhea.
However, the fluid usually stays in the middle ear and causes ear fullness, pressure and hearing loss. It's as if you’re in a barrel, underwater or in a tunnel.
This condition is often misdiagnosed early on. Your otolaryngologist may see fluid behind the eardrum and try to treat the middle ear fluid with medication, which will not improve your hearing.
The doctor may then recommend a ventilation tube (or PE tube) that can be placed in the doctor's office. In this procedure, a small incision is made in the eardrum, and the fluid is suctioned out. A grommet, or ventilation tube, is placed into the incision and suspended in the eardrum.
From this point, the ear drains almost constantly through the grommet. The drainage can vary anywhere from a thin, clear, watery drainage to a slightly thicker, yellowish drainage.
Despite antibiotics and antibiotic eardrops, the drainage will not cease (usually it will get worse at night or in the morning and better during the day when you are upright). The otolaryngologist will either refer the patient to an ear specialist (otologist/neurotologist) or have the patient collect some of the drainage for analysis. The test, tau (or beta-2) transferrin, is diagnostic for spinal fluid if positive.
Once the diagnosis of spinal fluid otorrhea is made, an imaging study is often ordered, usually a CT scan of the temporal bone, to identify the site of the leak and to plan for surgery.
Most of the time, this condition can be repaired, the can be leak stopped and the can be symptoms relieved.
Treatment involves an operation to repair the hole in the dura (with soft tissue such as abdominal fat) and the hole in the tegmen (with the patient’s own bone). This can be done from below (a "transmastoid" approach) or from above (a "middle fossa" approach). Your surgeon will determine the type of surgical approach that is used. The size and location of the defect will affect the decision.