Abstract
Objectives To describe transnasal Eustachian tube (ET) occlusion with a liquid embolic solution
for lateral skull base cerebrospinal fluid (CSF) leaks.
Design A lateral skull base CSF fistula model was developed by the authors using fresh cadaveric
heads. Using a transtympanic needle, regulated pressurized pigmented saline was continuously
instilled into the middle ear space and visualized endoscopically in the nasopharynx.
An angioembolization catheter was then placed through the cartilaginous ET orifice
just medial to the bony ET. Under endoscopic and fluoroscopic guidance, a column of
liquid embolic agent was deployed into the bony ET segment up to the middle ear space.
Setting Tertiary care academic center.
Participants Cadaveric specimens.
Main Outcome Measures Cessation of CSF flow after occlusion at supraphysiologic pressures.
Results In two cadavers, a CSF fistula model was developed and endoscopic visualization of
irrigant flow into the nasopharynx was confirmed. Fluoroscopy provided adequate anatomic
views of the ET and middle ear, in addition to dynamic views of embolization. Cessation
of flow after occlusion was successfully achieved with pressures up to 25 mm Hg, which
exceeds normal physiological intracranial pressure.
Conclusion Eustachian tube occlusion with a liquid embolic solution is feasible in a novel cadaveric
CSF leak model. In the future, this relatively short, straightforward procedure may
become an outpatient alternative to manage intermittent or low-flow CSF fistulae following
lateral skull base surgery.
Keywords
cerebrospinal fluid leak - vestibular schwannoma - onyx - fluoroscopy - lateral skull
base surgery
