The helicotrema is located at the apex and provides a connection between which two scalae?

The helicotrema is located at the apex and provides a connection between which two scalae?

• A. Scala media and scala tympani
• B. Scala vestibuli and scala tympani
• C. Scala vestibuli and scala media
• D. Endolymphatic space and perilymphatic space

Answer: (B)

The helicotrema is the opening at the cochlear apex that links the scala vestibuli and the scala tympani. This small passage lets perilymph flow between these two perilymph-filled compartments, which helps equilibrate pressure for very low-frequency sounds that travel all the way to the apex. The scala media, containing endolymph, remains separate and does not connect via the helicotrema, and the endolymphatic space is not the connection here. So the two scalae bridged by the helicotrema are the scala vestibuli and the scala tympani.

The helicotrema is the opening at the cochlear apex that links the scala vestibuli and the scala tympani. This small passage lets perilymph flow between these two perilymph-filled compartments, which helps equilibrate pressure for very low-frequency sounds that travel all the way to the apex. The scala media, containing endolymph, remains separate and does not connect via the helicotrema, and the endolymphatic space is not the connection here. So the two scalae bridged by the helicotrema are the scala vestibuli and the scala tympani.