bill’s bar

Location: • Lies in petrous part of the temporal bone • Opens into posterior cranial fossa. • It is divided by a transverse ridge (crista falciformis) and vertical crest (Bill’s bar):   Quadrant Structure Anterosuperior Facial nerve Anteroinferior Cochlear nerve Posterosuperior Superior vestibular nerve Posteroinferior Inferior vestibular nerve   Mnemonic : “Seven up, Coke down, Balance behind” • Seven […]