1178 SURFACE AND SURGICAL ANATOMY. 
by chipping off the hamular process with a small chisel introduced at the posterior 
extremity of the lateral relief incisions. 
Naso-pharynx.—To explore the upper or nasal division of the pharynx the 
finger should be hooked upwards behind the soft palate. Anteriorly, the finger 
readily detects the sharp posterior border of the vomer, the posterior nares, and the 
posterior extremity of the middle and inferior turbinals, The roof of the space Is 
formed by the basilar process of the occipital bone, while upon the posterior wall is 
a transverse bony ridge caused by the projection of the anterior arch of the atlas. 
Upon the /ateral walls of the naso-pharynx are the openings of the Eustachian 
tubes, situated $ in. behind the posterior extremities of the inferior turbinals (Fig. 
639). The orifices, bounded superiorly and posteriorly by a prominent margin, are 
directed onnieeds and forwards, and, therefore, in a direction favourable to the 
passage of the Eustachian catheter. Behind the prominent posterior margin of the 
orifice 1s a lateral recess of the pharynx known as the fossa of Rosenmiiller, in which 
the point of the Eustachian catheter is apt to become engaged. Upon the roof and 
posterior wall of the pharynx, down to the level of the anterior arch of the atlas, 
and extending laterally as far as the Eustachian orifices, is a collection of adenoid 
tissue, the pharyngeal tonsil. Hypertrophy of this tissue constitutes the condition 
known as “ adenoids,’ the harmful effects of which are due to their interference 
with nasal respiration. Upon the centre of the pharyngeal tonsil is an orifice 
leading into a small recess into which numerous mucous glands open. The 
structures felt in the post-nasal space may be rendered visible by reflecting the 
light upon a small mirror placed immediately behind and below the soft palate 
(posterior rhinoscopy). The lower part of the inferior turbinal is obscured from 
view by the bulging of the upper surface of the soft palate. 
In plugging the posterior nares, it is unportant to remember that these openings 
measure nearly one inch in the vertical and half an inch in the transverse direction. 
In the child, owing to the small size of the face, the vertical diameter of the naso- 
pharynx is relativ ely much smaller than in the adult. 
The lymphatics of the pharynx join the upper deep cervical glands, one of which 
lies internal to the carotid vessel between the lateral recess of the pharynx and 
the prevertebral fascia. In children suppuration originating in this gland is the 
commonest cause of a retro-pharyngeal abscess. 
In the adult the four upper cervical vertebrae can be explored from the mouth, 
while in the ez/d the finger can also reach as far down as the sixth vertebra and the 
back of the cricoid cartilage. 
THE NECK. 
The general envelope of deep cervical fascia, along with the processes and partitions 
which proceed from its deep surface, subdivides the neck into compartments which 
hmit and determine the spread of pus. The most important compartment is the 
central or visceral compartment, bounded anteriorly by the pretracheal fascia, pos- 
teriorly by the prevertebral fascia, and laterally by the fascia forming the vascular 
compartment. Posteriorly, this compartment extends from the base of the skull 
downwards into the posterior mediastinum ; anteriorly, it extends from the hyoid 
bone into the anterior part of the superior mediastinum. -Abscesses in the visceral 
compartment are either secondary to disease of the organs it contains, or the result 
of a primary suppurative cellulitis, A tubercular abscess originating in one of the 
retropharyngeal lymphatic glands hes in front of the prevertebral fascia, and points 
towards the posterior wall of the pharynx; abscesses secondary to disease of the 
cervical vertebrae lie behind the prevertebral fascia, and spread laterally behind 
the vascular compartment; they point behind the sterno-mastoid, and should be 
opened through an incision at the posterior border of the muscle, the surgeon 
keeping to the anterior aspect of the transverse processes in order to avoid the 
structures in the vascular compartment (Chiene). 
In front of the visceral compartment is a small muscular compartment containing 
the depressor muscles of the hyoid bone ; anterior to it again, in the region of the 
supra-sternal notch, is the small supra-sternal compartment, containing the lower 
