posterior septal branches of sphenopalatine artery posterior septal branches of sphenopalatine artery crossing the under surface of the sphenoid the sphenopalatine artery ends on the nasal septum as the posterior septal branches; these anastomose with the ethmoidal arteries and the septal branch of the superior labial; one branch descends in a groove on the vomer to the incisive canal and anastomoses with the descending palatine artery. posterior septal branches of sphenopalatine arterydetailssourcesphenopalatine arteryidentifierslatinrami septales posteriores arteriae sphenopalatinaeta98a12.2.05.090ta24462fma71690anatomical terminology