Translabyrinthine Fistula Closure in Inner Ear Malformations with Otogenic Cerebrospinal Fluid Leak.

Inner ear malformations can cause abnormal communication between the inner ear and subarachnoid space, leading to otogenic cerebrospinal fluid (CSF) leakage and subsequent bacterial meningitis. Persistent leakage may result in recurrent meningitis, which is associated with neurological sequelae and poor prognosis; thus, early diagnosis and surgical intervention are essential. Various surgical strategies have been reported, commonly termed middle ear obliteration and inner ear obliteration. However, their definitions remain ambiguous, and techniques vary widely in approach and effectiveness. This study describes 2 pediatric cases of incomplete partition type I (IP-I) malformation complicated by recurrent meningitis that were treated with translabyrinthine fistula closure via the lateral semicircular canal, a form of inner ear obliteration. Both patients exhibited high vestibular CSF pressure due to hypoplasia of the internal auditory canal fundus. Patient 1 had undergone 4 previous window closure surgeries elsewhere without success, whereas Patient 2 had no residual hearing and required prompt management. In both cases, the fistula was directly identified and sealed with a three-layer construct under direct visualization, allowing secure closure. Postoperative follow-up revealed no recurrence of meningitis for >8 years in Case 1 and more than 1 year in Case 2, without complications. This technique may represent a reasonable treatment option for controlling CSF leakage in severe inner ear malformations, including cases refractory to conventional treatments, even at the cost of sacrificing inner ear function. Using 2 representative pediatric cases, this study presents a case-based review that clarifies the classification, indications, and limitations of current surgical strategies for otogenic CSF leakage associated with inner ear malformations.