Line 2:1·"Gross anatomy" is not a recognised heading for this article type.
Oxford Comma
suggestion
"The glossopharyngeal, vagus and accessory nerves have rootlets between the olive and inferior cerebellar peduncle. The facial nerve arises at the just above the olive, inferior to the pons."
Line 5:11·Use the Oxford comma in 'glossopharyngeal, vagus and accessory'.