Suprameatal triangle externally represents:

Suprameatal triangle, also known as MacEwen's triangle, is seen in temporal bone of skull, in  norma lateralis view. It is a small area/depression present posterior and superior to external acoustic meatus. It forms the lateral wall of mastoid antrum. It is of importance to surgeons performing cortical mastoidectomy. Boundaries of Suprameatal triangle: Superiorly: By supramastoid crest. Anteriorly: By posterosuperior margin of EAM (external acoustic meatus). Posteriorly: Vertical tangent to posterior margin of EAM (external acoustic meatus).   Anteroinferiorly: By presence of suprameatal spine. Key Concept:  Suprameatal triangle, also known as MacEwen's triangle, is seen in temporal bone of skull, in norma lateralis view. It represents mastoid antrum.