<prompt> Facial recess or the posterior sinus is bounded by -Medially by the vertical part of VII nerveLaterally by the chorda tympaniAbove by the fossa incudisAll of the above  <response>: Facial recess or Posterior sinus It is a depression in the posterior wall of the middle ear.It is bounded by:Medially Vertical part of VIII nerveLaterally Chorda tympaniAbove Fossa incudisImportance This recess is important surgically, as direct access can be made through this into the middle ear without disturbing posterior canal wall. Posterior tympanotomy approach 