Relation of the Supraorbital Nerve and Vessels to the Notch and Foramen of the Supraorbital Margin

Thirty-nine head-halves of the Japanese cadavers from our dissecting room were investigated. Results obtained are as follows: 1. The so-called supraorbital and frontal notches have a transverse ligament at their mouth. By this, one can distinguish whether the nerves and the vessels running together, pass inside or outside the notches, as in the case where the passage is a foramen.2. The nerve takes always the inside course while in a c onsiderable number of the cases the vessels running together with the nerve pass outside the foramen or notch (Table 3).3. Therefore, the so-called supraorbital and frontal foramina and notches are essentially the passages for the nerves. We could distinguish the following foramina and notches:a) supraorbital notch (F1-2 19/38) and foramen (F1-2,3/39), common for the lateral and medial branches of the supraorbital nerve PNAb) flateral supraorbital foramen (F1.12/39) and notch (I12,4/39), or the lateral branch (N2) of the supraorbital:c) medial supraorbital notch (I1,13/39) and foramen (F2 4/39), for the medial branch (N2): andd) supratrochlear foramen (F3.2.38) and notch (I2 1/38), for the supratrochlear nerve (N2).4. In about one half of the cases there was found only one notch or foramen for the supraorbital nerve. In the cases of two notches and/or foramina, they did not always represent the respective passages for the lateral and the medial branches of the supraorbital; they were sometimes for the supraorbital and supratrochlear nerves respectively. In one case three separate passages for the lateral and medial branches and the supratrochlear nerve were found. (Table 4).5. The supraorbital artery and vein run generally together with the supraorbital nerve or its lateral branch, but sometimes it may run in company with the medial branch, in a rare instance even with the supratrochlear nerve.6. The position of these foramina and notches were examined (Fig.6). The common psasage for the supraorbital nerve (I1+2or F1+2) is apt to lie in the intermediate region between the separate passages for N1 and N2. The distribution diagram of I1+2 and F1+2 is suggestive of a bimodal distribution, the significance of which, however, is unknown.