Introduction

Cerebrospinal fluid (CSF) otorrhea, the escape of CSF through the ear, represents a critical defect in the integrity of the temporal bone [1,2]. While often secondary to trauma or skull base surgery, the incidence of spontaneous CSF otorrhea is increasingly recognized, particularly in patients with predisposing factors such as elevated intracranial pressure or anatomic problems like tegmen tympani (the roof of the middle ear) bone defects [3,4].

A routine myringotomy, typically performed to manage middle ear effusion, then serves as the critical inciting event. By creating a direct communication between the fluid-filled middle ear and the external environment, the procedure converts a contained or nasally draining leak into an active otologic fistula, resulting in persistent, clear watery drainage [5]. This active leakage not only poses a significant burden to the patient but, more importantly, establishes a direct pathway for infection, increasing the risk of potentially fatal meningitis [6].

We present the case of a five-year-old boy with bilateral profound sensorineural hearing loss and no prior imaging in whom a routine left myringotomy for recurrent otitis media unexpectedly produced a high-flow, pulsatile CSF otorrhea, ultimately attributed to a common cavity deformity with a fistula from the vestibule through the oval window. CSF leakage from congenital inner ear malformations, including its precipitation by myringotomy or ventilation tube placement, is a recognized phenomenon [5,7]. The value of this report lies less in the rarity of the entity itself than in the unexpected intraoperative scenario it highlights: a high-flow leak discovered during a routine procedure in a child without prior meningitis or an established diagnosis, requiring immediate temporary measures before definitive repair could be planned. We use this case to highlight (1) the recognition and acute intraoperative management of unexpected high-flow CSF otorrhea, and (2) the rationale for preoperative temporal bone imaging in children with profound sensorineural hearing loss before middle-ear instrumentation.