Henry Gray (18251861). Anatomy of the Human Body. 1918.
3b. 5. The Sinuses of the Dura Mater
(Sinus Duræ Matris). Ophthalmic Veins and Emissary Veins
The sinuses of the dura mater are venous channels which drain the blood from the brain; they are devoid of valves, and are situated between the two layers of the dura mater and lined by endothelium continuous with that which lines the veins. They may be divided into two groups: (1) a postero-superior, at the upper and back part of the skull, and (2) an antero-inferior, at the base of the skull.
The postero-superior group comprises the
FIG. 566 Superior sagittal sinus laid open after remova of the skull cap. The chordæ Willisii are clearly seen. The venous lacunæ are also well shown; from two of them probes are passed into the superior sagittal sinus. (Poirier and Charpy.) (See enlarged image)
The superior sagittal sinus (sinus sagittalis superior; superior longitudinal sinus) (Figs. 566,567) occupies the attached or convex margin of the falx cerebri. Commencing at the foramen cecum, through which it receives a vein from the nasal cavity, it runs from before backward, grooving the inner surface of the frontal, the adjacent margins of the two parietals, and the superior division of the cruciate eminence of the occipital; near the internal occipital protuberance it deviates to one or other side (usually the right), and is continued as the corresponding transverse sinus. It is triangular in section, narrow in front, and gradually increases in size as it passes backward. Its inner surface presents the openings of the superior cerebral veins, which run, for the most part, obliquely forward, and open chiefly at the back part of the sinus, their orifices being concealed by fibrous folds; numerous