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Updated: Apr 5, 2026

Intrathecal Application of a Fluorescent Dye for the Identification of Cerebrospinal Fluid Leaks in Cochlear Malformation
Published on: February 29, 2020
Spontaneous middle cranial fossa cerebrospinal fluid otorrhea in adults
1University of Illinois at Chicago, Chicago, Illinois, U.S.A.
Objectives/Hypothesis:
The goals of this study are to: 1) investigate the urgency for repair of middle cranial fossa spontaneous cerebrospinal fluid (CSF) leaks in adults, and 2) review the literature and treatment recommendations for adult spontaneous CSF otorrhea.
Data Sources:
1) All patients who were referred to a tertiary center with spontaneous CSF otorrhea, exposed middle cranial fossa dura, or encephalocele from 2004 to 2015; and 2) landmark references on spontaneous CSF leaks
Review Methods:
Electronic medical records of patients with a documented spontaneous CSF leak, exposed dura, or encephalocele were reviewed. Subjects were excluded if they had a congenital, traumatic, or iatrogenic CSF leak. Main outcome measure was duration of CSF leak and development of meningitis after clinical presentation.
Results:
Twenty-two patients (27 ears) who were at risk for meningitis from spontaneous CSF otorrhea, encephalocele, or a dural breach with or without mastoiditis were evaluated. Duration of CSF leaks in patients who refused repair or who continued to have CSF leak after repair or prior to successful repair ranged from 4 months to 11 years. Duration of encephaloceles and dural exposure in an uninfected mastoid ranged from 24 months to 6 years. Only one patient presented with meningitis. None of these 22 patients developed meningitis during the time periods they were under our care.
Conclusion:
Should patients with CSF otorrhea, exposed dura, or encephalocele refuse operation, it may be reasonable to follow them with close observation and education about warning signs for meningitis.
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