Source:http://linkedlifedata.com/resource/umls/id/C0444567
FMA: Anatomical conduit space that connects two adjacent body spaces, surrounded by two or more subdivisions of two or more organs or organ parts. Examples: right atrioventricular orifice, orifice of artery, hilum of kidney, porta hepatis.,UWDA: Anatomical surface that bounds two adjacent body spaces, surrounded by two or more subdivisions of two or more organs. Examples: right atrioventricular orifice, orifice of artery, hilum of kidney, porta hepatis.