Approaches to Repairing Skull Base Defects for the Prevention of Cerebrospinal Fluid (CSF) Leakage

Cerebrospinal fluid (CSF) rhinorrhoea refers to any situation wherein CSF leaks nasally. This occurs when the subarachnoid space is in continuity with the nose as a result of a gap in the arachnoid and dura mater and some discontinuity of the bony structures of the skull. It is frequently a complex matter to assess and treat CSF rhinorrhoea. Laboratory assessment of nasal discharge to show whether CSF is present is not invariably accurate, whilst imaging may fail to demonstrate leakage that comes from a small hole or may not reveal several simultaneous sites whereby CSF leakage is occurring. Due to these limitations, unwarranted surgery and insufficient interventions have both occurred. CSF leaks fall into the following categories: trauma-related, iatrogenic, and spontaneous (in other words, idiopathic). Trauma to the face (which can be blunt or penetrating in character) may lead to CSF leakage. Surgical oncological operations (either ENT or neurosurgery) may result in iatrogenic leaks, as may functional endoscopic sinus surgery (FESS). The majority of cases which would previously have been classed as essential are currently considered likely to be due to raised ICP, as occurs in idiopathic intracranial hypertension (IIH). Anomalous congenital skull malformations and particular neoplasms may also result in CSF discharge through the nose. In this chapter, approaches to repairing skull base defects for the prevention of cerebrospinal fluid (CSF) leakage are presented.