Surgical management of middle cranial fossa bone defects: meningoencephalic herniation and cerebrospinal fluid leaks

Abstract

Along the medical practice of an Otologist he/she will face middle cranial fossa (MCF) bone defects. The purpose of this study is to contribute to the understanding of this possible life threatening condition, and to share and discuss our management approach. A literature review is also presented.

Study design: Retrospective case series at García-Ibáñez Otology and Skull base private center referral.

Methods: This study is based on the analysis of data collected from 19 cases of temporal bone meningoencephalic herniations surgically treated from 2006 to 2018. The follow-up ranged from 18 to 162 months with a mean average of 44.5 months.

Main findings: Meningoencephalic herniations were divided into four etiologic groups: spontaneous (24.8%), secondary to chronic otitis media (21.8%), iatrogenic (45.9%), and posttraumatic (7.5%). Different surgical techniques were used as treatment: transmastoid (TM) approach (27.8%), MCF approach (27.8%), combined technique (transmastoid plus minicraniotomy, 3%), and middle ear obliteration with blind sac closure of the external auditory canal (41.4%).

Conclusions: Variables like bilateral hearing level, size and location of the bone defect and existence of CSF leak should be analyzed to select the safest and most effective closing surgical approach.

Keywords: Cerebrospinal fluid (CSF) leak; Meningoencephalic herniation; Middle cranial Fossa; Temporal bone defect.