<prompt> Lateral wall of mastoid antrum is related to ?Superficial temporal aeryExternal auditory canalEmissary veinMeningeal aery  <response>: MacEwens triangle or suprameatal triangle overlies the lateral wall of mastoid antrum. It is bounded above by supramastoid crest, anteroinferiorly by posterosuperior margin of external auditory canal and posteriorly by a tangent drawn from zygomatic arch. 