s
otherwise apparently healthy. Without warning, the child seems to
choke, has great difficulty in breathing, with inspiratory stridor and
indrawing of the epigastrium; he rapidly becomes cyanosed, and in the
majority of cases dies in a few minutes--_thymus death_. No
satisfactory explanation of the sudden onset of the symptoms is
forthcoming, but it appears to be associated with something which
suddenly narrows the mediastinal space, such as backward bending of
the head, or venous engorgement of the thymus gland. Cases are
recorded in which an attack has come on during the administration of a
general anaesthetic; in some instances the patient has suffered from
the generalised status lymphaticus.

#Tumours of the Carotid Gland or Glomus Carotica# (_Potato-like tumour
of the neck_).--The carotid gland under normal conditions is about the
size of a grain of corn, and lies to the posterior aspect of the
bifurcation of the carotid. It is sometimes the seat of
_endothelioma_. The tumour has a definite capsule, is moderately firm
and elastic, increases in size slowly and gradually for a time, and
then may grow more rapidly. Its relation to the vessels is
characteristic: as it grows it envelops the common carotid and its
branches, and becomes adherent to the internal jugular vein; and it
may come to implicate the nerves in the neck, particularly the vagus
and its recurrent branch, and the cervical sympathetic.

It gives rise to few symptoms, and in the majority of cases the
surgeon is consulted on account of the disfigurement resulting from
the presence of the swelling in the neck. This swelling is ovoid,
smooth or slightly lobulated; it lies at the level of the bifurcation
of the carotid, and tends to grow upwards rather than downwards; it is
movable from side to side, but not up and down; it lies under the
sterno-mastoid, and the skin is not implicated. There is transmitted
pulsation in the tumour, but no expansion.

The diagnosis has to be made from lymphoma, adenoma, tuberculous
glands, sarcoma, and carcinoma.

In a large proportion of the cases operated upon it has been necessary
to ligate the carotids and to excise portions of the internal jugular
vein, and as severe cerebral symptoms are liable to ensue the
mortality has hitherto been high. Operation is therefore only to be
recommended when the growth is rapid, or the symptoms have become
urgent.

CHAPTER XXVII

THE THYREOID GLAND

Surgical Anatomy--P