Perilymph within the scala tympani communicates with cerebrospinal fluid through a narrow channel that also serves as a pressure-release route during sudden barometric change. Which structure is this?
- A Vestibular aqueduct
- B Cochlear aqueduct ✓
- C Endolymphatic duct
- D Aqueduct of Sylvius
Correct answer: B. Cochlear aqueduct
Explanation
The cochlear aqueduct runs from the scala tympani near the round window to the subarachnoid space of the posterior cranial fossa, allowing perilymph-CSF communication and pressure equilibration. Patency of this channel explains why CSF leaks can present as perilymphatic fistulae. The vestibular aqueduct contains the endolymphatic duct and sac, which belong to the endolymphatic system, so options A and C describe the wrong compartment.
Reference: Cummings Otolaryngology: Head and Neck Surgery, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.