establishing drainage.

AFTER-EFFECTS OF HEAD INJURIES

Various after-effects may follow injuries of the head. Thus, for
example, _chronic interstitial changes_ (sclerosis) may spread from an
area of cicatrisation in the brain; or _softening_ may ensue, either
in the form of pale areas of necrosis (white softening) or of
haemorrhagic patches (red softening). The symptoms vary with the area
implicated. _Adhesions_ between the brain and its membranes may
produce severe headache and attacks of vertigo, especially on the
patient making sudden exertion.

After a head injury, the patient's whole mental attitude is sometimes
changed, so that he becomes irritable, unstable, and incapacitated for
brain-work--_traumatic neurasthenia_. In some cases self-control is
lost, and alcoholic and drug habits are developed.

#Traumatic epilepsy# may ensue as a result of some circumscribed
cortical lesion, such as a spicule of bone projecting into the
cortex, the presence of adhesions between the membranes and the brain,
a cicatrix in the brain tissue leading to sclerosis or a haemorrhagic
cyst in the membranes or cerebral tissue.

The convulsive attacks are of the Jacksonian type, beginning in one
particular group of muscles and spreading to neighbouring groups till
all the muscles of the body may be affected. The convulsions may begin
soon after the injury, for example, when the cause is a fragment of
bone irritating the cortex; in other cases it may be several years
before they make their appearance. The onset is usually sudden, and
the "signal symptom"--for example, jerking of the thumb, conjugate
deviation of the eyes, or motor aphasia--indicates the seat of the
lesion. At first the attacks only recur at intervals of, it may be
weeks or months, but as time goes on they become more and more
frequent, until there may be as many as forty or fifty in a day.
Sometimes the patient loses consciousness during the fit; sometimes he
remains partly conscious. In course of time the same degenerative
changes as occur in other forms of epilepsy ensue: certain groups of
muscles may become paralysed; the patient may pass into a state of
idiocy, or into what is known as the "status epilepticus," in which
the fits succeed one another without remission, the breathing becomes
stertorous, the temperature rising, the pulse becoming very rapid;
finally coma supervenes, and the patient dies.

_Treatment._--The administration of bromides is only palli