THE HEAD AND NECK 1067 



The Scalp and Temporal Region. 



Scalp — Fascia. — ^The superficial fascia is firm and granular, and 

 is separated into lobules by fibrous processes which pass between 

 the skin and the epicranial aponeurosis. The deep fascia is repre- 

 sented by the epicranial aponeurosis of the occipito-frontalis muscle, 

 to be presently described. 



Nerves of the Scalp Proper. — ^The great, small, and least or third 

 occipital nerves, and the mastoid branch of the great auricular 

 have been already described. In the fronto-parietal region two 

 sensory nerves are met with, namely, the supra-orbital and supra- 

 trochlear, both of which are derived from the frontal nerv^e, which 

 is one of the branches of the ophthalmic division of the fifth cranial 

 nerve. 



The supra-orbital nerve, which is of large size, leaves the orbit 

 through the supra-orbital foramen. It then ascends, lying at first 

 beneath the upper part of the orbicularis palpebrarum and the 

 frontalis muscles, but subsequently piercing the latter muscle in 

 two branches, outer and inner. The outer branch is the larger of 

 the two, and its offsets extend well back over the parietal region. 

 As the supra-orbital nerve passes through the supra-orbital foramen 

 it furnishes one or two twigs to the mucous membrane of the frontal 

 air-sinus and to the diploe of the frontal bone, and, after emerging 

 from the foramen, it sends downwards palpebral branches to the 

 integument of the upper eyelid. Thereafter the nerve supplies the 

 integument of the fronto-parietal region. 



The outer and inner branches of the supra-orbital nerve sometimes emerge 

 from the orbit separately, the outer branch passing through the supra-orbital 

 foramen, and the inner branch passing over the frontal notch. 



The supratrochlear nerve, which is of small size, is internal to 



the supra-orbital nerve. It leaves the orbit close to the internal 

 angular process of the frontal bone, where it lies above the trochlea 

 or pulley of the superior oblique muscle of the eyeball. It then 

 ascends beneath the upper part of the orbicularis palpebrarum 

 and the frontalis muscles, and, piercing the latter muscle, it has a 

 limited distribution to the frontal integument close to the median 

 line. As the nerve leaves the orbit it furnishes palpebral twigs 

 to the inner part of the integument of the upper eyelid. 



Arteries. — ^The third part of the occipital artery has been already 

 described. The arteries of the fronto-parietal region are three in 

 number, namely, the supra-orbital, frontal, and anterior branch 

 of the superficial temporal. 



The supra-orbital artery is a branch of the ophthalmic, and 

 emerges from the orbit with the supra-orbital nerve. It is dis- 

 tributed to the structures covering the frontal bone, and anasto- 

 moses with the frontal, and the anterior division of the superficial 

 temporal, arteries. In the supra-orbital foramen it furnishes one or 

 two branches to the mucous membrane of the frontal air-sinus and to 



