Obliteration for Cerebrospinal Fluid Leak Repair
Obliteration for cerebrospinal fluid (CSF) leak repair is used for lateral skull base or posterior fossa lesions that result in a spinal fluid leak that drips down the Eustachian tube. Spinal fluid leaks occur in 5% to 10% of skull base surgeries, such as vestibular schwannomas.
The surgery involves a transnasal, transoral endoscopic approach. The endoscope is inserted into the tip in the nose. A tonsil mouth gag is inserted into the mouth to provide greater access to the Eustachian tube, which facilitates dissection and suturing. Dr. Poe uses an angled microdebrider blade passed through the mouth to remove mucosa 360 degrees around the Eustachian tube and as high as possible in the lumen. The lumen is filled with AlloDerm (a cadaveric dermis product) and oversewn shut.
“It’s important to only remove surface mucosa and not allow the microdebrider to dig deeper into tissue, which can create significant bleeding,” Dr. Poe said. “We have to always be aware of the location of the internal carotid artery in this area, but keeping the dissection within the cartilaginous Eustachian tube provides an adequate margin of safety.” The complete obliteration will normally scar over fully, and long-term outcomes are excellent, because it shouldn’t recur, Dr. Poe said.