the transverse sinus as a sequel to chronic suppuration in the mastoid
antrum and middle ear. It also occurs in relation to the peripheral
veins, but in these it can seldom be recognised as a separate entity,
being merged in the general infective process from which it takes
origin. Its occurrence may be inferred, if in the course of a
suppurative lesion there is a sudden rise of temperature, with pain,
redness, and swelling along the line of a venous trunk, and a rapidly
developed œdema of the limb, with pitting of the skin on pressure. In
rare cases a localised abscess forms in the vein and points towards the
surface.
_Treatment._--Attention must be directed towards the condition with
which the phlebitis is associated. Ligation of the vein on the cardiac
side of the thrombus with a view to preventing embolism is seldom
feasible in the peripheral veins, although, as will be pointed out
later, the jugular vein is ligated with this object in cases of
phlebitis of the transverse sinus.
VARIX--VARICOSE VEINS
The term varix is applied to a condition in which veins are so altered
in structure that they remain permanently dilated, and are at the same
time lengthened and tortuous. Two types are met with: one in which
dilatation of a large superficial vein and its tributaries is the most
obvious feature; the other, in which bunches of distended and tortuous
vessels develop at one or more points in the course of a vein, a
condition to which Virchow applied the term _angioma racemosum venosum_.
The two types may occur in combination.
Any vein in the body may become varicose, but the condition is rare
except in the veins of the lower extremity, in the veins of the
spermatic cord (varicocele), and in the veins of the anal canal
(hæmorrhoids).
We are here concerned with varix as it occurs in the veins of the lower
extremity.
_Etiology._--Considerable difference of opinion exists as to the
essential cause of varix. The weight of evidence is in favour of the
view that, when dilatation is the predominant element, it results from a
congenital deficiency in the number, size, and strength of the valves of
the affected veins, and in an inherent weakness in the vessel walls.
The _angioma racemosum venosum_ is probably also due to a congenital
alteration in the structure of the vessels, and is allied to tumours of
blood vessels. The view that varix is congenital in origin, as was first
suggested by Virchow, is supported by the fact that in a large
proportion of cases the condition is hereditary; not only may several
members of the same family in succeeding generations suffer from varix,
but it is often found that the same vein, or segment of a vein, is
involved in all of them. The frequent occurrence of varix in youth is
also an indication of its congenital origin.
In the majority of cases it is only when some exciting factor comes into
operation that the clinical phenomena associated with varix appear. The
most common exciting cause is increased pressure within the veins, and
this may be produced in a variety of ways. In certain diseases of the
heart, lungs, and liver, for example, the venous pressure may be so
raised as to cause a localised dilatation of such veins as are
congenitally weak. The direct pressure of a tumour, or of the gravid
uterus on the large venous trunks in the pelvis, may so obstruct the
flow as to distend the veins of the lower extremity. It is a common
experience in women that the signs of varix date from an antecedent
pregnancy. The importance of the wearing of tight garters as a factor in
the production of varicose veins has been exaggerated, although it must
be admitted that this practice is calculated to aggravate the condition
when it is once established. It has been proved experimentally that the
backward pressure in the veins may be greatly increased by straining, a
fact which helps to explain the frequency with which varicosity occurs
in the lower limbs of athletes and of those whose occupation involves
repeated and violent muscular efforts. There is reason to believe,
moreover, that a sudden strain may, by rupturing the valves and so
rendering them incompetent, induce varicosity independently of any
congenital defect. Prolonged standing or walking, by allowing gravity to
act on the column of blood in the veins of the lower limbs, is also an
important determining factor in the production of varix.
Thrombosis of the deep veins--in the leg, for example--may induce marked
dilatation of the superficial veins, by throwing an increased amount of
work upon them. This is to be looked upon rather as a compensatory
hypertrophy of the superficial vessels than as a true varix.
_Morbid Anatomy._--In the lower extremity the varicosity most commonly
affects the vessels of the great saphena system; less frequently those
of the small saphena system. Sometimes both systems are involved, and
large communicating branches may develop between the two.
The essential lesion is the absence or deficiency of valves, so that
they are incompetent and fail to support the column of blood which bears
back upon them. Normally the valves in the femoral and iliac veins and
in the inferior vena cava are imperfectly developed, so that in the
erect posture the great saphena receives a large share of the backward
pressure of the column of venous blood.
The whole length of the vein may be affected, but as a rule the disease
is confined to one or more segments, which are not only dilated, but are
also increased in length, so that they become convoluted. The adjacent
loops of the convoluted vein are often bound together by fibrous tissue.
All the coats are thickened, chiefly by an increased development of
connective tissue, and in some cases changes similar to those of
arterio-sclerosis occur. The walls of varicose veins are often
exceedingly brittle. In some cases the thickening is uniform, and in
others it is irregular, so that here and there thin-walled sacs or
pouches project from the side of the vein. These pouches vary in size
from a bean to a hen's egg, the larger forms being called _venous
cysts_, and being most commonly met with in the region of the saphenous
opening and of the opening in the popliteal fascia. Such pouches, being
exposed to injury, are frequently the seat of thrombosis (Fig. 66).
[Illustration: FIG. 66.--Thrombosis in Tortuous and Pouched Great
Saphena Vein, in longitudinal section.]
_Clinical Features._--Varix is most frequently met with between puberty
and the age of thirty, and the sexes appear to suffer about equally.
The amount of discomfort bears no direct proportion to the extent of
the varicosity. It depends rather upon the degree of pressure in the
veins, as is shown by the fact that it is relieved by elevation of the
limb. When the whole length of the main trunk of the great saphena is
implicated, the pressure in the vein is high and the patient suffers a
good deal of pain and discomfort. When, on the contrary, the upper part
of the saphena and its valves are intact, and only the more distal veins
are involved, the pressure is not so high and there is comparatively
little suffering. The usual complaint is of a sense of weight and
fulness in the limb after standing or walking, sometimes accompanied by
actual pain, from which relief is at once obtained by raising the limb.
Cramp-like pains in the muscles are often associated with varix of the
deep veins.
The dilated and tortuous vein can be readily seen and felt when the
patient is examined in the upright posture. In advanced cases, bead-like
swellings are sometimes to be detected over the position of the valves,
and, on running the fingers along the course of the vessel, a firm
ridge, due to periphlebitis, may be detected on each side of the vein.
When the limb is œdematous, the outline of the veins is obscured, but
they can be identified on palpation as gutter-like tracks. When large
veins are implicated, a distinct impulse on coughing may be seen to pass
down as far as the knee; and if the vessel is sharply percussed a fluid
wave may be detected passing both up and down the vein.
If the patient is placed on a couch and the limb elevated, the veins are
emptied, and if pressure is then made over the region of the saphenous
opening and the patient allowed to stand up, so long as the great
saphena system alone is involved, the veins fill again very slowly from
below. If the small saphena system also is involved, and if
communicating branches are dilated, the veins fill up from below more
rapidly. When the pressure over the saphenous opening is removed, the
blood rapidly rushes into the varicose vessels from above; this is known
as Trendelenburg's test.
The most marked dilatation usually occurs on the medial side of the
limb, between the middle of the thigh and the middle of the calf, the
arrangement of the veins showing great variety (Fig. 67).
There are usually one or more bunches of enlarged and tortuous veins in
the region of the knee. Frequently a large branch establishes a
communication between the systems of the great and small saphenous veins
in the region of the popliteal space, or across the front of the upper
part of the tibia. The superficial position of this last branch and its
proximity to the bone render it liable to injury.
[Illustration: FIG. 67.--Extensive Varix of Internal Saphena System on
Left Leg, of many years' standing.]
The small veins of the skin of the ankle and foot often show as fine
blue streaks arranged in a stellate or arborescent manner, especially in
women who have borne children.
_Complications._--When the varix is of long standing, the skin in the
lower part of the leg sometimes assumes a mahogany-brown or bluish hue,
as a result of the _deposit of blood pigment_ in the tissues, and this
is frequently a precursor of ulceration.
_Chronic dermatitis_ (_varicose eczema_) is often met with in the lower
part of the leg, and is due to interference with the nutrition of the
skin. The incompetence of the valves allows the pressure in the varicose
veins to equal that in the arterioles, so that the capillary circulation
is impeded. From the same cause the blood in the deep veins is enabled
to enter the superficial veins, where the backward pressure is so great
that the blood flows down again, and so a vicious circle is established.
The blood therefore loses more and more of its oxygen, and so fails to
nourish the tissues.
The _ulcer_ of the leg associated with varicose veins has already been
described.
_Hæmorrhage_ may take place from a varicose vein as a result of a wound
or of ulceration of its wall. Increased intra-venous pressure produced
by severe muscular strain may determine rupture of a vein exposed in the
floor of an ulcer. If the limb is dependent, the incompetency of the
valves permits of rapid and copious bleeding, which may prove fatal,
particularly if the patient is intoxicated when the rupture takes place
and no means are taken to arrest the hæmorrhage. The bleeding may be
arrested at once by elevating the limb, or by applying pressure directly
over the bleeding point.
_Phlebitis and thrombosis_ are common sequelæ of varix, and may prove
dangerous, either by spreading into the large venous trunks or by giving
rise to emboli. The larger the varix the greater is the tendency for a
thrombus to spread upwards and to involve the deep veins. Thrombi
usually originate in venous cysts or pouches, and at acute bends on the
vessel, especially when these are situated in the vicinity of the knee,
and are subjected to repeated injuries--for example in riding.
Phleboliths sometimes form in such pouches, and may be recognised in a
radiogram. In a certain proportion of cases, especially in elderly
people, the occurrence of thrombosis leads to cure of the condition by
the thrombus becoming organised and obliterating the vein.
_Treatment._--At best the treatment of varicose veins is only
palliative, as it is obviously impossible to restore to the vessels
their normal structure. The patient must avoid wearing anything, such as
a garter, which constricts the limb, and any obvious cause of direct
pressure on the pelvic veins, such as a tumour, persistent
constipation, or an ill-fitting truss, should be removed. Cardiac,
renal, or pulmonary causes of venous congestion must also be treated,
and the functions of the liver regulated. Severe forms of muscular
exertion and prolonged standing or walking are to be avoided, and the
patient may with benefit rest the limb in an elevated position for a few
hours each day. To support the distended vessels, a closely woven silk
or worsted stocking, or a light and porous form of elastic bandage,
applied as a puttee, should be worn. These appliances should be put on
before the patient leaves his bed in the morning, and should only be
removed after he lies down at night. In this way the vessels are never
allowed to become dilated. Elastic stockings, and bandages made entirely
of india-rubber, are to be avoided. In early and mild cases these
measures are usually sufficient to relieve the patient's discomfort.
_Operative Treatment._--In aggravated cases, when the patient is
suffering pain, when his occupation is interfered with by repeated
attacks of phlebitis, or when there are large pouches on the veins,
operative treatment is called for. The younger the patient the clearer
is the indication to operate. It may be necessary to operate to enable a
patient to enter one of the public services, even although no symptoms
are present. The presence of an ulcer does not contra-indicate
operation; the ulcer should be excised, and the raw surface covered with
skin grafts, before dealing with the veins.
The _operation of Trendelenburg_ is especially appropriate to cases in
which the trunk of the great saphena vein in the thigh is alone
involved. It consists in exposing three or four inches of the vein in
its upper part, applying a ligature at the upper and lower ends of the
exposed portion, and, after tying all tributary branches, resecting this
portion of the vein.
The procedure of C. H. Mayo is adapted to cases in which it is desirable
to remove longer segments of the veins. It consists in the employment of
special instruments known as "ring-enucleators" or "vein-strippers," by
means of which long portions of the vein are removed through
comparatively small incisions.
An alternative procedure consists in avulsing segments of the vein by
means of Babcock's stylet, which consists of a flexible steel rod, 30
inches in length, with acorn-shaped terminals. The instrument is passed
along the lumen of the segment to be dealt with, and a ligature applied
around the vein above the bulbous end of the stylet enables nearly the
whole length of the great saphena vein to be dragged out in one piece.
These methods are not suitable when the veins are brittle, when there
are pouches or calcareous deposits in their walls, or where there has
been periphlebitis binding the coils together.
Mitchell of Belfast advises exposing the varices at numerous points by
half-inch incisions, and, after clamping the vein between two pairs of
forceps, cutting it across and twisting out the segments of the vein
between adjacent incisions. The edges of the incisions are sutured; and
the limb is firmly bandaged from below upwards, and kept in an elevated
position. We have employed this method with satisfactory results.
The treatment of the complications of varix has already been considered.
ANGIOMA[4]
[4] In the description of angiomas we have followed the teaching of the
late John Duncan.
Tumours of blood vessels may be divided, according to the nature of the
vessels of which they are composed, into the capillary, the venous, and
the arterial angiomas.
CAPILLARY ANGIOMA
The most common form of capillary angioma is the nævus or congenital
telangiectasis.
#Nævus.#--A nævus is a collection of dilated capillaries, the afferent
arterioles and the efferent venules of which often share in the
dilatation. Little is known regarding the _etiology_ of nævi beyond the
fact that they are of congenital origin. They often escape notice until
the child is some days old, but attention is usually drawn to them
within a fortnight of birth. For practical purposes the most useful
classification of nævi is into the cutaneous, the subcutaneous, and the
mixed forms.
_The cutaneous nævus_, "mother's mark," or "port-wine stain," consists
of an aggregation of dilated capillaries in the substance of the skin.
On stretching the skin the vessels can be seen to form a fine network,
or to run in leashes parallel to one another. A dilated arteriole or a
vein winding about among the capillaries may sometimes be detected.
These nævi occur on any part of the body, but they are most frequently
met with on the face. They may be multiple, and vary greatly in size,
some being no bigger than a pin-head, while others cover large areas of
the body. In colour they present every tint from purple to brilliant
red; in the majority there is a considerable dash of blue, especially in
cold weather.
Unlike the other forms of nævi, the cutaneous variety shows little
tendency to disappear, and it is especially persistent when associated
with overgrowth of the epidermis and of the hairs--_nævoid mole_.
The _treatment_ of the cutaneous nævus is unsatisfactory, owing to the
difficulty of removing the nævus without leaving a scar which is even
more disfiguring. Very small nævi may be destroyed by a fine pointed
Paquelin thermo-cautery, or by escharotics, such as nitric acid. For
larger nævi, radium and solidified carbon dioxide ("CO₂ snow") may be
used. The extensive port-wine stains so often met with on the face are
best left alone.
The _subcutaneous nævus_ is comparatively rare. It constitutes a
well-defined, localised tumour, which may possess a distinct capsule,
especially when it has ceased to grow or is retrogressing. On section,
it presents the appearance of a finely reticulated sponge.
Although it may be noticed at, or within a few days of, birth, a
subcutaneous nævus is often overlooked, especially when on a covered
part of the body, and may not be discovered till the patient is some
years old. It forms a rounded, lobulated swelling, seldom of large size
and yielding a sensation like that of a sponge; the skin over it is
normal, or may exhibit a bluish tinge, especially in cold weather. In
some cases the tumour is diminished by pressing the blood out of it, but
slowly fills again when the pressure is relaxed, and it swells up when
the child struggles or cries. From a cold abscess it is diagnosed by the
history and progress of the swelling and by the absence of fluctuation.
When situated over one of the hernial openings, it closely simulates a
hernia; and when it occurs in the middle line of the face, head, or
back, it may be mistaken for such other congenital conditions as
meningocele or spina bifida. When other means fail, the use of an
exploring needle clears up the diagnosis.
_Mixed Nævus._--As its name indicates, the mixed nævus partakes of the
characters of the other two varieties; that is, it is a subcutaneous
nævus with involvement of the skin.
It is frequently met with on the face and head, but may occur on any
part of the body. It also affects parts covered by mucous membrane, such
as the cheek, tongue, and soft palate. The swelling is rounded or
lobulated, and projects beyond the level of its surroundings. Sometimes
the skin is invaded by the nævoid tissue over the whole extent of the
tumour, sometimes only over a limited area. Frequently the margin only
is of a bright-red colour, while the skin in the centre resembles a
cicatrix. The swelling is reduced by steady pressure, and increases in
size and becomes tense when the child cries.
[Illustration: FIG. 68.--Mixed Nævus of Nose which was subsequently
cured by Electrolysis.]
_Prognosis._--The rate of growth of the subcutaneous and mixed forms of
nævi varies greatly. They sometimes increase rapidly, especially during
the first few months of life; after this they usually grow at the same
rate as the child, or more slowly. There is a decided tendency to
disappearance of these varieties, fully 50 per cent. undergoing natural
cure by a process of obliteration, similar to the obliteration of
vessels in cicatricial tissue. This usually begins about the period of
the first dentition, sometimes at the second dentition, and sometimes at
puberty. On the other hand, an increased activity of growth may be shown
at these periods. The onset of natural cure is recognised by the tumour
becoming firmer and less compressible, and, in the mixed variety, by the
colour becoming less bright. Injury, infection, or ulceration of the
overlying skin may initiate the curative process.
Towards adult life the spaces in a subcutaneous nævus may become greatly
enlarged, leading to the formation of a cavernous angioma.
_Treatment._--In view of the frequency with which subcutaneous and mixed
nævi disappear spontaneously, interference is only called for when the
growth of the tumour is out of proportion to that of the child, or when,
from its situation--for example in the vicinity of the eye--any marked
increase in its size would render it less amenable to treatment.
The methods of treatment most generally applicable are the use of radium
and carbon dioxide snow, igni-puncture, electrolysis, and excision.
For nævi situated on exposed parts, where it is desirable to avoid a
scar, the use of _radium_ is to be preferred. The tube of radium is
applied at intervals to different parts of the nævus, the duration and
frequency of the applications varying with the strength of the
emanations and the reaction produced. The object aimed at is to induce
obliteration of the nævoid tissue by cicatricial contraction without
destroying the overlying skin. _Carbon-dioxide snow_ may be employed in
the same manner, but the results are inferior to those obtained by
radium.
_Igni-puncture_ consists in making a number of punctures at different
parts of the nævus with a fine-pointed thermo-cautery, with the object
of starting at each point a process of cicatrisation which extends
throughout the nævoid tissue and so obliterates the vessels.
_Electrolysis_ acts by decomposing the blood and tissues into their
constituent elements--oxygen and acids appearing at the positive,
hydrogen and bases at the negative electrode. These substances and gases
being given off in a nascent condition, at once enter into new
combinations with anything in the vicinity with which they have a
chemical affinity. In the nævus the practical result of this reaction is
that at the positive pole nitric acid, and at the negative pole caustic
potash, both in a state of minute subdivision, make their appearance.
The effect on the tissues around the positive pole, therefore, is
equivalent to that of an acid cauterisation, and on those round the
negative pole, to an alkaline cauterisation.
As the process is painful, a general anæsthetic is necessary. The
current used should be from 20 to 80 milliampères, gradually increasing
from zero, without shock; three to six large Bunsen cells give a
sufficient current, and no galvanometer is required. Steel needles,
insulated with vulcanite to within an eighth of an inch of their points,
are the best. Both poles are introduced into the nævus, the positive
being kept fixed at one spot, while the negative is moved about so as to
produce a number of different tracks of cauterisation. On no account
must either pole be allowed to come in contact with the skin, lest a
slough be formed. The duration of the sitting is determined by the
effect produced, as indicated by the hardening of the tumour, the
average duration being from fifteen to twenty minutes. If pallor of the
skin appears, it indicates that the needles are too near the surface, or
that the blood supply to the integument is being cut off, and is an
indication to stop. To cauterise the track and so prevent bleeding, the
needles should be slowly withdrawn while the current is flowing. When
the skin is reached the current is turned off. The punctures are covered
with collodion. Six or eight weeks should be allowed to elapse before
repeating the procedure. From two to eight or ten sittings may be
necessary, according to the size and character of the nævus.
_Excision_ is to be preferred for nævi of moderate size situated on
covered parts of the body, where a scar is of no importance. Its chief
advantages over electrolysis are that a single operation is sufficient,
and that the cure is speedy and certain. The operation is attended with
much less hæmorrhage than might be expected.
#Cavernous Angioma.#--This form of angioma consists of a series of large
blood spaces which are usually derived from the dilatation of the
capillaries of a subcutaneous nævus. The spaces come to communicate
freely with one another by the disappearance of adjacent capillary
walls. While the most common situation is in the subcutaneous tissue, a
cavernous angioma is sometimes met with in internal organs. It may
appear at any age from early youth to middle life, and is of slow growth
and may become stationary. The swelling is rounded or oval, there is no
pulsation or bruit, and the tumour is but slightly compressible. The
treatment consists in dissecting it out.
#Aneurysm by Anastomosis# is the name applied to a vascular tumour in
which the arteries, veins, and capillaries are all involved. It is met
with chiefly on the upper part of the trunk, the neck, and the scalp. It
tends gradually to increase in size, and may, after many years, attain
an enormous size. The tumour is ill-defined, and varies in consistence.
It is pulsatile, and a systolic bruit or a "thrilling" murmur may be
heard over it. The chief risk is hæmorrhage from injury or ulceration.
[Illustration: FIG. 69.--Cirsoid Aneurysm of Forehead in a boy æt. 10.
(Mr. J. W. Dowden's case.)]
The _treatment_ is conducted on the same lines as for nævus. When
electrolysis is employed, it should be directed towards the afferent
vessels; and if it fails to arrest the flow through these, it is useless
to persist with it. In some cases ligation of the afferent vessels has
been successful.
#Arterial Angioma# or #Cirsoid Aneurysm#.--This is composed of the
enlarged branches of an arterial trunk. It originates in the smaller
branches of an artery--usually the temporal--and may spread to the main
trunk, and may even involve branches of other trunks with which the
affected artery anastomoses.
The condition is probably congenital in origin, though its appearance is
frequently preceded by an injury. It almost invariably occurs in the
scalp, and is usually met with in adolescent young adults.
The affected vessels slowly increase in size, and become tortuous, with
narrowings and dilatations here and there. Grooves and gutters are
frequently found in the bone underlying the dilated vessels.
There is a constant loud bruit in the tumour, which greatly troubles the
patient and may interfere with sleep. There is no tendency either to
natural cure or to rupture, but severe and even fatal hæmorrhage may
follow a wound of the dilated vessels.
[Illustration: FIG. 70.--Cirsoid Aneurysm of Orbit and Face, which
developed after a blow on the Orbit with a cricket ball.
(From a photograph lent by Sir Montagu Cotterill.)]
The condition may be treated by excision or by electrolysis. In excision
the hæmorrhage is controlled by an elastic tourniquet applied
horizontally round the head, or by ligation of the feeding trunks. In
large tumours the bleeding is formidable. In many cases electrolysis is
to be preferred, and is performed in the same way as for nævus. The
positive pole is placed in the centre of the tumour, while the negative
is introduced into the main affluents one after another.
ANEURYSM
An aneurysm is a sac communicating with an artery, and containing fluid
or coagulated blood.
Two types are met with--the pathological and the traumatic. It is
convenient to describe in this section also certain conditions in which
there is an abnormal communication between an artery and a
vein--arterio-venous aneurysm.
PATHOLOGICAL ANEURYSM
In this class are included such dilatations as result from weakening of
the arterial coats, combined, in most cases, with a loss of elasticity
in the walls and increase in the arterial tension due to
arterio-sclerosis. In some cases the vessel wall is softened by
arteritis--especially the embolic form--so that it yields before the
pressure of the blood.
Repeated and sudden raising of the arterial tension, as a result, for
example, of violent muscular efforts or of excessive indulgence in
alcohol, plays an important part in the causation of aneurysm. These
factors probably explain the comparative frequency of aneurysm in those
who follow such arduous occupations as soldiers, sailors,
dock-labourers, and navvies. In these classes the condition usually
manifests itself between the ages of thirty and fifty--that is, when the
vessels are beginning to degenerate, although the heart is still
vigorous and the men are hard at work. The comparative immunity of women
may also be explained by the less severe muscular strain involved by
their occupations and recreations.
Syphilis plays an important part in the production of aneurysm, probably
by predisposing the patient to arterio-sclerosis and atheroma, and
inducing an increase in the vascular tension in the peripheral vessels,
from loss of elasticity of the vessel wall and narrowing of the lumen as
a result of syphilitic arteritis. It is a striking fact that aneurysm is
seldom met with in women who have not suffered from syphilis.
#Varieties--Fusiform Aneurysm.#--When the _whole circumference_ of an
artery has been weakened, the tension of the blood causes the walls to
dilate uniformly, so that a fusiform or tubular aneurysm results. All
the coats of the vessel are stretched and form the sac of the aneurysm,
and the affected portion is not only dilated but is also increased in
length. This form is chiefly met with in the arch of the aorta, but may
occur in any of the main arterial trunks. As the sac of the aneurysm
includes all three coats, and as the inner and outer coats are usually
thickened by the deposit in them of connective tissue, this variety
increases in size slowly and seldom gives rise to urgent symptoms.
As a rule a fusiform aneurysm contains fluid blood, but when the intima
is roughened by disease, especially in the form of calcareous plates,
shreds of clot may adhere to it.
It has little tendency to natural cure, although this is occasionally
effected by the emerging artery becoming occluded by a clot; it has also
little tendency to rupture.
#Sacculated Aneurysm.#--When a _limited area_ of the vessel wall is
weakened--for example by atheroma or by other form of arteritis--this
portion yields before the pressure of the blood, and a sacculated
aneurysm results. The internal and middle coats being already damaged,
or, it may be, destroyed, by the primary disease, the stress falls on
the external coat, which in the majority of cases constitutes the sac.
To withstand the pressure the external coat becomes thickened, and as
the aneurysm increases in size it forms adhesions to surrounding
tissues, so that fasciæ, tendons, nerves, and other structures may be
found matted together in its wall. The wall is further strengthened by
the deposit on its inner aspect of blood-clot, which may eventually
become organised.
The contents of the sac consist of fluid blood and a varying amount of
clot which is deposited in concentric layers on the inner aspect of the
sac, where it forms a pale, striated, firm mass, which constitutes a
laminated clot. Near the blood-current the clot is soft, red, and
friable (Fig. 72). The laminated clot not only strengthens the sac,
enabling it to resist the blood-pressure and so prevent rupture, but, if
it increases sufficiently to fill the cavity, may bring about cure. The
principle upon which all methods of treatment are based is to imitate
nature in producing such a clot.
Sacculated aneurysm, as compared with the fusiform variety, tends to
rupture and also to cure by the formation of laminated clot; natural
cure is sometimes all but complete when extension and rupture occur and
cause death.
An aneurysm is said to be _diffused_ when the sac ruptures and the blood
escapes into the cellular tissue.
#Clinical Features of Aneurysm.#--Surgically, the sacculated is by far
the most important variety. The outstanding feature is the existence in
the line of an artery of a globular swelling, which pulsates. The
pulsation is of an expansile character, which is detected by observing
that when both hands are placed over the swelling they are separated
with each beat of the heart. If the main artery be compressed on the
cardiac side of the swelling, the pulsation is arrested and the tumour
becomes smaller and less tense, and it may be still further reduced in
size by gentle pressure being made over it so as to empty it of fluid
blood. On allowing the blood again to flow through the artery, the
pulsation returns at once, but several beats are required before the sac
regains its former size. In most cases a distinct thrill is felt on
placing the hand over the swelling, and a blowing, systolic murmur may
be heard with the stethoscope. It is to be borne in mind that
occasionally, when the interchange of blood between an aneurysm and the
artery from which it arises is small, pulsation and bruit may be slight
or even absent. This is also the case when the sac contains a
considerable quantity of clot. When it becomes filled with
clot--_consolidated aneurysm_--these signs disappear, and the clinical
features are those of a solid tumour lying in contact with an artery,
and transmitting its pulsation.
A comparison of the pulse in the artery beyond the seat of the aneurysm
with that in the corresponding artery on the healthy side, shows that on
the affected side the wave is smaller in volume, and delayed in time. A
pulse tracing shows that the normal impulse and dicrotic waves are lost,
and that the force and rapidity of the tidal wave are diminished.
[Illustration: FIG. 71.--Radiogram of Aneurysm of Aorta, showing
laminated clot and erosion of bodies of vertebræ. The intervertebral
discs are intact.]
An aneurysm exerts pressure on the surrounding structures, which are
usually thickened and adherent to it and to one another. Adjacent veins
may be so compressed that congestion and œdema of the parts beyond are
produced. Pain, disturbances of sensation, and muscular paralyses may
result from pressure on nerves. Such bones as the sternum and vertebræ
undergo erosion and are absorbed by the gradually increasing pressure of
the aneurysm. Cartilage, on the other hand, being elastic, yields before
the pressure, so that the intervertebral discs or the costal cartilages
may escape while the adjacent bones are destroyed (Fig. 71). The skin
over the tumour becomes thinned and stretched, until finally a slough
forms, and when it separates hæmorrhage takes place.
[Illustration: FIG. 72.--Sacculated Aneurysm of Abdominal Aorta nearly
filled with laminated clot. Note greater density of clot towards
periphery.]
In the progress of an aneurysm towards rupture, timely clotting may
avert death for the moment, but while extension in one direction has
been arrested there is apt to be extension in another, with imminence of
rupture, or it may be again postponed.
#Differential Diagnosis.#--The diagnosis is to be made from other
pulsatile swellings. Pulsation is sometimes transmitted from a large
artery to a tumour, a mass of enlarged lymph glands, or an inflammatory
swelling which lies in its vicinity, but the pulsation is not
expansile--a most important point in differential diagnosis. Such
swellings may, by appropriate manipulation, be moved from the artery and
the pulsation ceases, and compression of the artery on the cardiac side
of the swelling, although it arrests the pulsation, does not produce any
diminution in the size or tension of the swelling, and when the pressure
is removed the pulsation is restored immediately.
Fluid swellings overlying an artery, such as cysts, abscesses, or
enlarged bursæ, may closely simulate aneurysm. An apparent expansion may
accompany the pulsation, but careful examination usually enables this to
be distinguished from the true expansion of an aneurysm. Compression of
the artery makes no difference in the size or tension of the swelling.
Vascular tumours, such as sarcoma and goitre, may yield an expansile
pulsation and a soft, whifling bruit, but they differ from an aneurysm
in that they are not diminished in size by compression of the main
artery, nor can they be emptied by pressure.
The exaggerated pulsation sometimes observed in the abdominal aorta, the
"pulsating aorta" seen in women, should not be mistaken for aneurysm.
#Prognosis.#--When _natural cure_ occurs it is usually brought about by
the formation of laminated clot, which gradually increases in amount
till it fills the sac. Sometimes a portion of the clot in the sac is
separated and becomes impacted as an embolus in the artery beyond,
leading to thrombosis which first occludes the artery and then extends
into the sac.
The progress of natural cure is indicated by the aneurysm becoming
smaller, firmer, less expansile, and less compressible; the murmur and
thrill diminish and the pressure effects become less marked. When the
cure is complete the expansile pulsation is lost, and there remains a
firm swelling attached to the vessel (_consolidated aneurysm_). While
these changes are taking place the collateral arteries become enlarged,
and an anastomotic circulation is established.
An aneurysm may prove _fatal_ by exerting pressure on important
structures, by causing syncope, by rupture, or from the occurrence of
suppuration. _Pressure_ symptoms are usually most serious from aneurysms
situated in the neck, thorax, or skull. Sudden fatal _syncope_ is not
infrequent in cases of aneurysm of the thoracic aorta.
_Rupture_ may take place through the skin, on a mucous or serous
surface, or into the cellular tissue. The first hæmorrhage is often
slight and stops naturally, but it soon recurs, and is so profuse,
especially when the blood escapes externally, that it rapidly proves
fatal. When the bleeding takes place into the cellular tissue, the
aneurysm is said to become _diffused_, and the extravasated blood
spreads widely through the tissues, exerting great pressure on the
surrounding structures.
The _clinical features_ associated with rupture are sudden and severe
pain in the part, and the patient becomes pale, cold, and faint. If a
comparatively small escape of blood takes place into the tissues, the
sudden alteration in the size, shape, and tension of the aneurysm,
together with loss of pulsation, may be the only local signs. When the
bleeding is profuse, however, the parts beyond the aneurysm become
greatly swollen, livid, and cold, and the pulse beyond is completely
lost. The arrest of the blood supply may result in gangrene. Sometimes
the pressure of the extravasated blood causes the skin to slough and,
later, give way, and fatal hæmorrhage results.
The _treatment_ is carried out on the same lines as for a ruptured
artery (p. 261), it being remembered, however, that the artery is
diseased and does not lend itself to reconstructive procedures.
_Suppuration_ may occur in the vicinity of an aneurysm, and the aneurysm
may burst into the abscess which forms, so that when the latter points
the pus is mixed with broken-down blood-clot, and finally free
hæmorrhage takes place. It has more than once happened that a surgeon
has incised such an abscess without having recognised its association
with aneurysm, with tragic results.
#Treatment.#--In treating an aneurysm, the indications are to imitate
Nature's method of cure by means of laminated clot.
_Constitutional treatment_ consists in taking measures to reduce the
arterial tension and to diminish the force of the heart's action. The
patient must be kept in bed. A dry and non-stimulating diet is
indicated, the quantity being gradually reduced till it is just
sufficient to maintain nutrition. Saline purges are employed to reduce
the vascular tension. The benefit derived from potassium iodide
administered in full doses, as first recommended by George W. Balfour,
probably depends on its depressing action on the heart and its
therapeutic benefit in syphilis. Pain or restlessness may call for the
use of opiates, of which heroin is the most efficient.
_Local Treatment._--When constitutional treatment fails, local measures
must be adopted, and many methods are available.
#Endo-aneurysmorrhaphy.#--The operation devised by Rudolf Matas in 1888
aims at closing the opening between the sac and its feeding artery, and
in addition, folding the wall of the sac in such a way as to leave no
vacant space. If there is marked disease of the vessel, Matas' operation
is not possible and recourse is then had to ligation of the artery just
above the sac.
_Extirpation of the Sac--The Old Operation._--The procedure which goes
by this name consists in exposing the aneurysm, incising the sac,
clearing out the clots, and ligating the artery above and below the sac.
This method is suitable to sacculated aneurysm of the limbs, so long as
they are circumscribed and free from complications. It has been
successfully practised also in aneurysm of the subclavian, carotid, and
external iliac arteries. It is not applicable to cases in which there is
such a degree of atheroma as would interfere with the successful
ligation of the artery. The continuity of the artery may be restored by
grafting into the gap left after excision of the sac a segment of the
great saphena vein.
_Ligation of the Artery._--The object of tying the artery is to diminish
or to arrest the flow of blood through the aneurysm so that the blood
coagulates both in the sac and in the feeding artery. The ligature may
be applied on the cardiac side of the aneurysm--proximal ligation, or to
the artery beyond--distal ligation.
_Proximal Ligation._--The ligature may be applied immediately above the
sac (Anel, 1710) or at a distance above (John Hunter, 1785). The
_Hunterian operation_ ensures that the ligature is applied to a part of
the artery that is presumably healthy and where relations are
undisturbed by the proximity of the sac; the best example is the
ligation of the superficial femoral artery in Scarpa's triangle or in
Hunter's canal for popliteal aneurysm; it is on record that Syme
performed this operation with cure of the aneurysm on thirty-nine
occasions.
It is to be noted that the Hunterian ligature does not aim at
_arresting_ the flow of blood through the sac, but is designed so to
diminish its volume and force as to favour the deposition within the sac
of laminated clot. The development of the collateral circulation which
follows upon ligation of the artery at a distance above the sac may be
attended with just that amount of return stream which favours the
deposit of laminated clot, and consequently the cure of the aneurysm;
the return stream may, however, be so forcible as to prevent coagulation
of the blood in the sac, or only to allow of the formation of a red
thrombus which may in its turn be dispersed so that pulsation in the sac
recurs. This does not necessarily imply failure to cure, as the
recurrent pulsation may only be temporary; the formation of laminated
clot may ultimately take place and lead to consolidation of the
aneurysm.
The least desirable result of the Hunterian ligature is met with in
cases where, owing to widespread arterial disease, the collateral
circulation does not develop and gangrene of the limb supervenes.
_Anel's ligature_ is only practised as part of the operation which deals
with the sac directly.
_Distal Ligation._--The tying of the artery beyond the sac, or of its
two branches where it bifurcates (Brasdor, 1760, and Wardrop, 1825), may
arrest or only diminish the flow of blood through the sac. It is less
successful than the proximal ligature, and is therefore restricted to
aneurysms so situated as not to be amenable to other methods; for
example, in aneurysm of the common carotid near its origin, the artery
may be ligated near its bifurcation, or in aneurysm of the innominate
artery, the carotid and subclavian arteries are tied at the seat of
election.
_Compression._--Digital compression of the feeding artery has been given
up except as a preparation for operations on the sac with a view to
favouring the development of a collateral circulation.
_Macewen's acupuncture or "needling"_ consists in passing one or more
fine, highly tempered steel needles through the tissues overlying the
aneurysm, and through its outer wall. The needles are made to touch the
opposite wall of the sac, and the pulsation of the aneurysm imparts a
movement to them which causes them to scarify the inner surface of the
sac. White thrombus forms on the rough surface produced, and leads to
further coagulation. The needles may be left in position for some hours,
being shifted from time to time, the projecting ends being surrounded
with sterile gauze.
The _Moore-Corradi method_ consists in introducing through the wall of
the aneurysm a hollow insulated needle, through the lumen of which from
10 to 20 feet of highly drawn silver or other wire is passed into the
sac, where it coils up into an open meshwork (Fig. 73). The positive
pole of a galvanic battery is attached to the wire, and the negative
pole placed over the patient's back. A current, varying in strength from
20 to 70 milliampères, is allowed to flow for about an hour. The hollow
needle is then withdrawn, but the wire is left _in situ_. The results
are somewhat similar to those obtained by needling, but the clot formed
on the large coil of wire is more extensive.
[Illustration: FIG. 73.--Radiogram of Innominate Aneurysm after
treatment by the Moore-Corradi method. Two feet of finely drawn silver
wire were introduced. The patient, a woman, æt. 47, lived for ten months
after operation, free from pain (cf. Fig. 75).]
Colt's method of wiring has been mainly used in the treatment of
abdominal aneurysm; gilt wire in the form of a wisp is introduced
through the cannula and expands into an umbrella shape.
_Subcutaneous Injections of Gelatin._--Three or four ounces of a 2 per
cent. solution of white gelatin in sterilised water, at a temperature of
about 100° F., are injected into the subcutaneous tissue of the abdomen
every two, three, or four days. In the course of a fortnight or three
weeks improvement may begin. The clot which forms is liable to soften
and be absorbed, but a repetition of the injection has in several cases
established a permanent cure.
_Amputation of the limb_ is indicated in cases complicated by
suppuration, by secondary hæmorrhage after excision or ligation, or by
gangrene. Amputation at the shoulder was performed by Fergusson in a
case of subclavian aneurysm, as a means of arresting the blood-flow
through the sac.
TRAUMATIC ANEURYSM
The essential feature of a traumatic aneurysm is that it is produced by
some form of injury which divides all the coats of the artery. The walls
of the injured vessel are presumably healthy, but they form no part of
the sac of the aneurysm. The sac consists of the condensed and thickened
tissues around the artery.
The injury to the artery may be a subcutaneous one such as a tear by a
fragment of bone: much more commonly it is a punctured wound from a stab
or from a bullet.
The aneurysm usually forms soon after the injury is inflicted; the blood
slowly escapes into the surrounding tissues, gradually displacing and
condensing them, until they form a sac enclosing the effused blood.
Less frequently a traumatic aneurysm forms some considerable time after
the injury, from gradual stretching of the fibrous cicatrix by which the
wound in the wall of the artery has been closed. The gradual stretching
of this cicatrix results in condensation of the surrounding structures
which form the sac, on the inner aspect of which laminated clot is
deposited.
A traumatic aneurysm is almost always sacculated, and, so long as it
remains circumscribed, has the same characters as a pathological
sacculated aneurysm, with the addition that there is a scar in the
overlying skin. A traumatic aneurysm is liable to become diffuse--a
change which, although attended with considerable risk of gangrene, has
sometimes been the means of bringing about a cure.
The treatment is governed by the same principles as apply to the
pathological varieties, but as the walls of the artery are not diseased,
operative measures dealing with the sac and the adjacent segment of the
affected artery are to be preferred.
ARTERIO-VENOUS ANEURYSM
An abnormal communication between an artery and a vein constitutes an
arterio-venous aneurysm. Two varieties are recognised--one in which the
communication is direct--_aneurysmal varix_; the other in which the
vein communicates with the artery through the medium of a sac--_varicose
aneurysm_.
Either variety may result from pathological causes, but in the majority
of cases they are traumatic in origin, being due to such injuries as
stabs, punctured wounds, and gun-shot injuries which involve both artery
and vein. In former times the most common situation was at the bend of
the elbow, the brachial artery being accidentally punctured in
blood-letting from the median basilic vein. Arterio-venous aneurysm is a
frequent result of injuries by modern high-velocity bullets--for
example, in the neck or groin.
In _aneurysmal varix_ the higher blood pressure in the artery forces
arterial blood into the vein, which near the point of communication with
the artery tends to become dilated, and to form a thick-walled sac,
beyond which the vessel and its tributaries are distended and tortuous.
The clinical features resemble those associated with varicose veins, but
the entrance of arterial blood into the dilated veins causes them to
pulsate, and produces in them a vibratory thrill and a loud murmur. In
those at the groin, the distension of the veins may be so great that
they look like sinuses running through the muscles, a feature that must
be taken into account in any operation.
As the condition tends to remain stationary, the support of an elastic
bandage is all that is required; but when the condition progresses and
causes serious inconvenience, it may be necessary to cut down and expose
the communication between the artery and vein, and, after separating the
vessels, to close the opening in each by suture; this may be difficult
or impossible if the parts are matted from former suppuration. If it is
impossible thus to obliterate the communication, the artery should be
ligated above and below the point of communication; although the risk of
gangrene is considerable unless means are taken to develop the
collateral circulation beforehand (Makins).
_Varicose aneurysm_ usually develops in relation to a traumatic
aneurysm, the sac becoming adherent to an adjacent vein, and ultimately
opening into it. In this way a communication between the artery and the
vein is established, and the clinical features are those of a
combination of aneurysm and aneurysmal varix.
As there is little tendency to spontaneous cure, and as the aneurysm is
liable to increase in size and finally to rupture, operative treatment
is usually called for. This is carried out on the same lines as for
aneurysmal varix, and at the same time incising the sac, turning out the
clots, and ligating any branches which open into the sac. If it can be
avoided, the vein should not be ligated.
ANEURYSMS OF INDIVIDUAL ARTERIES
#Thoracic Aneurysm.#--All varieties of aneurysm occur in the aorta, the
fusiform being the most common, although a sacculated aneurysm
frequently springs from a fusiform dilatation.
The _clinical features_ depend chiefly on the direction in which the
aneurysm enlarges, and are not always well marked even when the sac is
of considerable size. They consist in a pulsatile swelling--sometimes in
the supra-sternal notch, but usually towards the right side of the
sternum--with an increased area of dulness on percussion. With the
X-rays a dark shadow is seen corresponding to the sac. Pain is usually a
prominent symptom, and is largely referable to the pressure of the
aneurysm on the vertebræ or the sternum, causing erosion of these bones.
Pressure on the thoracic veins and on the air-passage causes cyanosis
and dyspnœa. When the œsophagus is pressed upon, the patient may have
difficulty in swallowing. The left recurrent nerve may be stretched or
pressed upon as it hooks round the arch of the aorta, and hoarseness of
the voice and a characteristic "brassy" cough may result from paralysis
of the muscles of the larynx which it supplies. The vagus, the phrenic,
and the spinal nerves may also be pressed upon. When the aneurysm is on
the transverse part of the arch, the trachea is pulled down with each
beat of the heart--a clinical phenomena known as the "tracheal tug."
Aneurysm of the descending aorta may, after eroding the bodies of the
vertebræ (Fig. 71) and posterior portions of the ribs, form a swelling
in the back to the left of the spine.
Inasmuch as obliteration of the sac and the feeding artery is out of the
question, surgical treatment is confined to causing coagulation of the
blood in an extension or pouching of the sac, which, making its way
through the parietes of the chest, threatens to rupture externally. This
may be achieved by Macewen's needles or by the introduction of wire into
the sac. We have had cases under observation in which the treatment
referred to has been followed by such an amount of improvement that the
patient has been able to resume a laborious occupation for one or more
years. Christopher Heath found that improvement followed ligation of the
left common carotid in aneurysm of the transverse part of the aortic
arch.
[Illustration: FIG. 74.--Thoracic Aneurysm, threatening to rupture
externally, but prevented from doing so by Macewen's needling. The
needles were left in for forty-eight hours.]
#Abdominal Aneurysm.#--Aneurysm is much less frequent in the abdominal
than in the thoracic aorta. While any of the large branches in the
abdomen may be affected, the most common seats are in the aorta itself,
just above the origin of the cœliac artery and at the bifurcation.
The _clinical features_ vary with the site of the aneurysm and with its
rapidity and direction of growth. A smooth, rounded swelling, which
exhibits expansile pulsation, forms, usually towards the left of the
middle line. It may extend upwards under cover of the ribs, downwards
towards the pelvis, or backward towards the loin. On palpation a
systolic thrill may be detected, but the presence of a murmur is neither
constant nor characteristic. Pain is usually present; it may be
neuralgic in character, or may simulate renal colic. When the aneurysm
presses on the vertebræ and erodes them, the symptoms simulate those of
spinal caries, particularly if, as sometimes happens, symptoms of
compression paraplegia ensue. In its growth the swelling may press upon
and displace the adjacent viscera, and so interfere with their
functions.
The _diagnosis_ has to be made from solid or cystic tumours overlying
the artery; from a "pulsating aorta"; and from spinal caries; much help
is obtained by the use of the X-rays.
The condition usually proves fatal, either by the aneurysm bursting into
the peritoneal cavity, or by slow leakage into the retro-peritoneal
tissue.
The Moore-Corradi method has been successfully employed, access to the
sac having been obtained by opening the abdomen. Ligation of the aorta
has so far been unsuccessful, but in one case operated upon by Keen the
patient survived forty-eight days.
#Innominate aneurysm# may be of the fusiform or of the sacculated
variety, and is frequently associated with pouching of the aorta. It
usually grows upwards and laterally, projecting above the sternum and
right clavicle, which may be eroded or displaced (Fig. 75). Symptoms of
pressure on the structures in the neck, similar to those produced by
aortic aneurysm, occur. The pulses in the right upper extremity and in
the right carotid and its branches are diminished and delayed. Pressure
on the right brachial plexus causes shooting pain down the arm and
muscular paresis on that side. Vaso-motor disturbances and contraction
of the pupil on the right side may result from pressure on the
sympathetic. Death may take place from rupture, or from pressure on the
air-passage.
[Illustration: FIG. 75.--Innominate Aneurysm in a woman, æt. 47, eight
months after treatment by Moore-Corradi method (cf. Fig. 73).]
The available methods of treatment are ligation of the right common
carotid and third part of the right subclavian (Wardrop's operation), of
which a number of successful cases have been recorded. Those most
suitable for ligation are cases in which the aneurysm is circumscribed
and globular (Sheen). If ligation is found to be impracticable, the
Moore-Corradi method or Macewen's needling may be tried.
#Carotid Aneurysms.#--Aneurysm of the _common carotid_ is more frequent
on the right than on the left side, and is usually situated either at
the root of the neck or near the bifurcation. It is the aneurysm most
frequently met with in women. From its position the swelling is liable
to press on the vagus, recurrent and sympathetic nerves, on the
air-passage, and on the œsophagus, giving rise to symptoms referable to
such pressure. There may be cerebral symptoms from interference with the
blood supply of the brain.
Aneurysm near the origin has to be diagnosed from subclavian,
innominate, and aortic aneurysm, and from other swellings--solid or
fluid--met with in the neck. It is often difficult to determine with
precision the trunk from which an aneurysm at the root of the neck
originates, and not infrequently more than one vessel shares in the
dilatation. A careful consideration of the position in which the
swelling first appeared, of the direction in which it has progressed, of
its pressure effects, and of the condition of the pulses beyond, may
help in distinguishing between aortic, innominate, carotid, and
subclavian aneurysms. Skiagraphy is also of assistance in recognising
the vessel involved.
Tumours of the thyreoid, enlarged lymph glands, and fatty and
sarcomatous tumours can usually be distinguished from aneurysm by the
history of the swelling and by physical examination. Cystic tumours and
abscesses in the neck are sometimes more difficult to differentiate on
account of the apparently expansile character of the pulsation
transmitted to them. The fact that compression of the vessel does not
affect the size and tension of these fluid swellings is useful in
distinguishing them from aneurysm.
_Treatment._--Digital compression of the vessel against the transverse
process of the sixth cervical vertebra--the "carotid tubercle"--has been
successfully employed in the treatment of aneurysm near the bifurcation.
Proximal ligation in the case of high aneurysms, or distal ligation in
those situated at the root of the neck, is more certain. Extirpation of
the sac is probably the best method of treatment, especially in those of
traumatic origin. These operations are attended with considerable risk
of hemiplegia from interference with the blood supply of the brain.
The _external carotid_ and the cervical portion of the _internal
carotid_ are seldom the primary seat of aneurysm, although they are
liable to be implicated by the upward spread of an aneurysm at the
bifurcation of the common trunk. In addition to the ordinary signs of
aneurysm, the clinical manifestations are chiefly referable to pressure
on the pharynx and larynx, and on the hypoglossal nerve. Aneurysm of the
internal carotid is of special importance on account of the way in which
it bulges into the pharynx in the region of the tonsil, in some cases
closely simulating a tonsillar abscess. Cases are on record in which
such an aneurysm has been mistaken for an abscess and incised, with
disastrous results.
_Aneurysmal varix_ may occur in the neck as a result of stabs or bullet
wounds. The communication is usually between the common carotid artery
and the internal jugular vein. The resulting interference with the
cerebral circulation causes headache, giddiness, and other brain
symptoms, and a persistent loud murmur is usually a source of annoyance
to the patient and may be sufficient indication for operative treatment.
#Intracranial aneurysm# involves the internal carotid and its branches,
or the basilar artery, and appears to be more frequently associated with
syphilis and with valvular disease of the heart than are external
aneurysms. It gives rise to symptoms similar to those of other
intracranial tumours, and there is sometimes a loud murmur. It usually
proves fatal by rupture, and intracranial hæmorrhage. The treatment is
to ligate the common carotid or the vertebral artery in the neck,
according to the seat of the aneurysm.
#Orbital Aneurysm.#--The term pulsating exophthalmos is employed to
embrace a number of pathological conditions, including aneurysm, in
which the chief symptoms are pulsation in the orbit and protrusion of
the eyeball. There may be, in addition, congestion and œdema of the
eyelids, and a distinct thrill and murmur, which can be controlled by
compression of the common carotid in the neck. Varying degrees of ocular
paralysis and of interference with vision may also be present.
These symptoms are due, in the majority of cases, to an aneurysmal varix
of the internal carotid artery and cavernous sinus, which is often
traumatic in origin, being produced either by fracture of the base of
the skull or by a punctured wound of the orbit. In other cases they are
due to aneurysm of the ophthalmic artery, to thrombosis of the cavernous
sinus, and, in rare instances, to cirsoid aneurysm.
If compression of the common carotid is found to arrest the pulsation,
ligation of this vessel is indicated.
#Subclavian Aneurysm.#--Subclavian aneurysm is usually met with in men
who follow occupations involving constant use of the shoulder--for
example, dock-porters and coal-heavers. It is more common on the right
side.
The aneurysm usually springs from the third part of the artery, and
appears as a tense, rounded, pulsatile swelling just above the clavicle
and to the outer side of the sterno-mastoid muscle. It occasionally
extends towards the thorax, where it may become adherent to the pleura.
The radial pulse on the same side is small and delayed. Congestion and
œdema of the arm, with pain, numbness, and muscular weakness, may result
from pressure on the veins and nerves as they pass under the clavicle;
and pressure on the phrenic nerve may induce hiccough. The aneurysm is
of slow growth, and occasionally undergoes spontaneous cure.
The conditions most likely to be mistaken for it are a soft, rapidly
growing sarcoma, and a normal artery raised on a cervical rib.
On account of the relations of the artery and of its branches, treatment
is attended with greater difficulty and danger in subclavian than in
almost any other form of external aneurysm. The available operative
measures are proximal ligation of the innominate, and distal ligation.
In some cases it has been found necessary to combine distal ligation
with amputation at the shoulder-joint, to prevent the collateral
circulation maintaining the flow through the aneurysm. Matas' operation
has been successfully performed by Hogarth Pringle.
#Axillary Aneurysm.#--This is usually met with in the right arm of
labouring men and sailors, and not infrequently follows an injury in the
region of the shoulder. The vessel may be damaged by the head of a
dislocated humerus or in attempts to reduce the dislocation, by the
fragments of a fractured bone, or by a stab or cut. Sometimes the vein
also is injured and an arterio-venous aneurysm established.
Owing to the laxity of the tissues, it increases rapidly, and it may
soon attain a large size, filling up the axilla, and displacing the
clavicle upwards. This renders compression of the third part of the
subclavian difficult or impossible. It may extend beneath the clavicle
into the neck, or, extending inwards may form adhesions to the chest
wall, and, after eroding the ribs, to the pleura.
The usual symptoms of aneurysm are present, and the pressure effects on
the veins and nerves are similar to those produced by an aneurysm of the
subclavian. Intra-thoracic complications, such as pleurisy or pneumonia,
are not infrequent when there are adhesions to the chest wall and
pleura. Rupture may take place externally, into the shoulder-joint, or
into the pleura.
Extirpation of the sac is the operation of choice, but, if this is
impracticable, ligation of the third part of the subclavian may be had
recourse to.
#Brachial aneurysm# usually occurs at the bend of the elbow, is of
traumatic origin, and is best treated by excision of the sac.
_Aneurysmal varix_, which was frequently met with in this situation in
the days of the barber-surgeons,--usually as a result of the artery
having been accidentally wounded while performing venesection of the
median basilic vein,--may be treated, according to the amount of
discomfort it causes, by a supporting bandage, or by ligation of the
artery above and below the point of communication.
Aneurysms of the vessels of the #forearm and hand# call for no special
mention; they are almost invariably traumatic, and are treated by
excision of the sac.
#Inguinal Aneurysm# (_Aneurysm of the Iliac and Femoral
Arteries_).--Aneurysms appearing in the region of Poupart's ligament may
have their origin in the external or common iliac arteries or in the
upper part of the femoral. On account of the tension of the fascia lata,
they tend to spread upwards towards the abdomen, and, to a less extent,
downwards into the thigh. Sometimes a constriction occurs across the
sac at the level of Poupart's ligament.
The pressure exerted on the nerves and veins of the lower extremity
causes pain, congestion, and œdema of the limb. Rupture may take place
externally, or into the cellular tissue of the iliac fossa.
These aneurysms have to be diagnosed from pulsating sarcoma growing from
the pelvic bones, and from an abscess or a mass of enlarged lymph glands
overlying the artery and transmitting its pulsation.
The method of treatment that has met with most success is ligation of
the common or external iliac, reached either by reflecting the
peritoneum from off the iliac fossa (extra-peritoneal operation), or by
going through the peritoneal cavity (trans-peritoneal operation).
#Gluteal Aneurysm.#--An aneurysm in the buttock may arise from the
superior or from the inferior gluteal artery, but by the time it forms a
salient swelling it is seldom possible to recognise by external
examination in which vessel it takes origin. The special symptoms to
which it gives rise are pain down the limb from pressure on the sciatic
nerve, and interference with the movements at the hip.
Ligation of the hypogastric (internal iliac) by the trans-peritoneal
route is the most satisfactory method of treatment. Extirpation of the
sac is difficult and dangerous, especially when the aneurysm has spread
into the pelvis.
#Femoral Aneurysm.#--Aneurysm of the femoral artery beyond the origin of
the profunda branch is usually traumatic in origin, and is more common
in Scarpa's triangle than in Hunter's canal. Any of the methods already
described is available for their treatment--the choice lying between
Matas' operation and ligation of the external iliac.
Aneurysm of the _profunda femoris_ is distinguished from that of the
main trunk by the fact that the pulses beyond are, in the former,
unaffected, and by the normal artery being felt pulsating over or
alongside the sac.
In _aneurysmal varix_, a not infrequent result of a bullet wound or a
stab, the communication with the vein may involve the main trunk of the
femoral artery. Should operative interference become necessary as a
result of progressive increase in size of the tumour, or progressive
distension of the veins of the limb, an attempt should be made to
separate the vessels concerned and to close the opening in each by
suture. If this is impracticable, the artery is tied above and below the
communication; gangrene of the limb may supervene, and we have observed
a case in which the gangrene extended up to the junction of the middle
and lower thirds of the thigh, and in which recovery followed upon
amputation of the thigh.
#Popliteal Aneurysm.#--This is the most common surgical aneurysm, and is
not infrequently met with in both limbs. It is generally due to disease
of the artery, and repeated slight strains, which are so liable to occur
at the knee, play an important part in its formation. In former times it
was common in post-boys, from the repeated flexion and extension of the
knee in riding.
The aneurysm is usually of the sacculated variety, and may spring from
the front or from the back of the vessel. It may exert pressure on the
bones and ligaments of the joint, and it has been known to rupture into
the articulation. The pain, stiffness, and effusion into the joint which
accompany these changes often lead to an erroneous diagnosis of joint
disease. The sac may press upon the popliteal artery or vein and their
branches, causing congestion and œdema of the leg, and lead to gangrene.
Pressure on the tibial and common peroneal nerves gives rise to severe
pain, muscular cramp, and weakness of the leg.
The differential diagnosis is to be made from abscess, bursal cyst,
enlarged glands, and sarcoma, especially pulsating sarcoma of one of the
bones entering into the knee joint.
The choice of operation lies between ligation of the femoral artery in
Hunter's canal, and Matas' operation of aneurysmo-arteriorrhaphy. The
success which attends the Hunterian operation is evidenced by the fact
that Syme performed it thirty-seven times without a single failure. If
it fails, the old operation should be considered, but it is a more
serious operation, and one which is more liable to be followed by
gangrene of the limb. Experience shows that ligation of the vein, or
even the removal of a portion of it, is not necessarily followed by
gangrene. The risk of gangrene is diminished by a course of digital
compression of the femoral artery, before operating on the aneurysm.
_Aneurysmal varix_ is sometimes met with in the region of the popliteal
space. It is characterised by the usual symptoms, and is treated by
palliative measures, or by ligation of the artery above and below the
point of communication.
_Aneurysm_ in the #leg and foot# is rare. It is almost always traumatic,
and is treated by excision of the sac.