The chordae Willisii in the superior sagittal sinus: morphology and classification.

Chordae Willisii, which are located in the superior sagittal sinus, have been examined in 65 bodies. Three clearly differentiated primary forms and several variations have been found. Chordae Willisii guarantee, as auxiliary structures, a laminar blood flow. Their construction and location within the sinus are well adapted to their function.