Spontaneous cerebrospinal fluid (CSF) leaks into the middle ear, known as CSF otorrhea, present a significant diagnostic challenge for otolaryngologists. Unlike cases stemming from temporal bone trauma, fractures, or meningitis, spontaneous CSF otorrhea occurs without obvious preceding causes in adults. This absence of clear etiology can obscure the diagnosis, making it difficult to discern CSF from other middle ear effusions or otorrhea.
The underlying mechanism often involves a defect in the tegmen tympani, through which the arachnoid membrane herniates. These defects can be congenital or arise from dynamic factors such as brain pulsations or increased intracranial pressure, leading to tears in the arachnoid membrane. Critically, tegmen defects can be multiple, meaning that identifying a single defect might not guarantee complete surgical resolution.
A review of nine adult cases of spontaneous CSF leak into the ear highlights the complexities of diagnosis and management. Patients commonly present with non-specific symptoms like aural fullness and middle ear effusion. Interestingly, the characteristic clear otorrhea, suggestive of CSF, often becomes apparent only after tympanostomy tube insertion. In this case series, a significant number of patients were found to have multiple tegmen defects and meningoencephaloceles confirmed during surgery.
Effective surgical repair is crucial. Procedures frequently involve a combined middle cranial fossa and transmastoid approach to address potential multiple defects comprehensively. Various materials are utilized for repair, including temporalis fascia, free muscle grafts, Oxycel cotton, calvarial bone, pericranium, bone wax, and fibrin glue, tailored to the specific defect characteristics and surgical approach.
In conclusion, diagnosing CSF middle ear effusion or otorrhea in adults requires a high index of suspicion, even in the absence of typical risk factors like trauma or meningitis. While initial symptoms can be subtle and mimic common ear conditions, recognizing the possibility of spontaneous CSF leak and employing confirmatory imaging are paramount for accurate diagnosis. Given the potential for multiple tegmen defects, a surgical strategy incorporating a middle fossa approach, either alone or combined with a transmastoid approach, should be strongly considered to ensure effective repair and prevent recurrence.
