The olfactory fossa is a depression located in the anterior cranial cavity, formed by the cribriform plate of the ethmoid bone.
This depression houses the olfactory bulb, a structure critical for the sense of smell. The cribriform plate, which forms the floor of the olfactory fossa, is a thin, perforated bone through which the olfactory nerves pass from the nasal cavity to the olfactory bulb in the brain.
Anatomy and Significance
- Location: Anterior cranial fossa, on either side of the crista galli.
- Formation: Primarily by the cribriform plate of the ethmoid bone. The lateral lamella forms its lateral border.
- Function: Provides space and protection for the olfactory bulb.
- Clinical Relevance: Deep or asymmetric olfactory fossae, along with thin lateral lamellae, increase the risk of injury to the skull base during endoscopic sinus surgery. This can lead to cerebrospinal fluid (CSF) leak or intracranial injury.
Potential Risks During Surgery
During functional endoscopic sinus surgery (FESS), the lateral lamella of the cribriform plate, which forms the lateral boundary of the olfactory fossa, is vulnerable to injury. A deep or asymmetric olfactory fossa further increases this risk. Injury to this area can result in:
- Cerebrospinal Fluid (CSF) Leak: Disruption of the dura mater can lead to leakage of CSF into the nasal cavity.
- Intracranial Injury: Damage to the brain tissue.
Therefore, surgeons must carefully assess the anatomy of the olfactory fossa prior to and during endoscopic sinus surgery to minimize the risk of complications.
