Repair of Tegmen Tympani Defect Presenting with Spontaneous Cerebrospinal Fluid Otorrhea Using the Middle Cranial Fossa Approach

Abstract

Spontaneous cerebrospinal fluid (CSF) otorrhea frequently occurs without temporal bone trauma, fracture, surgery, or any identifiable causes. It is usually associated with tegmen tympani defects of the temporal bone in adults. The congenital origin theory and the arachnoid granulation theory have been accepted to explain the tegmen tympani defect. Magnetic resonance imaging (MRI) and computed tomography (CT) are used to show the defects, brain tissue, and the meninges. We recently encountered three cases of spontaneous CSF otorrhea with a defect on the tegmental plate of the temporal bone. High-resolution CT (HRCT) scan of the temporal bones showed the tegmen tympani defects. The defects were successfully repaired with temporal muscle fascia or fascia lata graft and fibrin glue using the middle cranial fossa approach via craniotomy.

Management of Spontaneous Cerebrospinal Fluid Leaks in the Middle Cranial Fossa and Bone Tegmen Tympani Defect in Patients with Meningitis and Rhinorrhea

“…According to many authors, MCF approach is often used for all bony defects, but they recommend taking into consideration the possible complications. Seizures, brain swelling, venous infarction and neurological deficits are the most dangerous pitfalls about this approach [16,21,22]. The transmastoid approach consists of a retroauricolar skin incision and a mastoidectomy.…”

Recurrent Otogenic Intracranial Sepsis: A Key Radiological Finding, Not to Be Missed

“…In this case, the defect in the tegmen tympani provided a route for the spread of otogenic sepsis intracranially [4]. Tegmen tympani defects have been found on autopsy in 15–35% of patients who present with otorrhoea, suggesting they are not uncommon [5]. There are various theories postulating why these defects occur, with suggestions that this could be due to constant cerebrospinal fluid (CSF) pressure, CSF from aberrant arachnoid granulation tissue causing pressure on the bone, idiopathic intracranial hypertension, and morbid obesity [4].…”

“…There are 3 possible approaches for the repair of tegmen tympani defects discussed in the literature, and the choice depends on various factors including location and size of the defect [5]. The three approaches are transmastoid approach, middle fossa craniotomy approach, or the combined approach [5].…”

“…The middle cranial fossa approach can be used for large/multiple defects and for anterior and medial site defects that are inaccessible via the transmastoid approach [5]. This approach usually involves making one or two burr holes to create a craniotomy.…”

“…Again the meningocele/encephalocele is identified and excised. The defect is repaired, with options for grafts including temporalis fascia, autologous bone/cartilage graft, or artificial grafts [5, 7].…”