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).



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 oedematous, 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.



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.

Haemorrhage 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 haemorrhage. 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 sequelae 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 naevus or congenital telangiectasis.

Naevus.—A naevus 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 naevi 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 naevi is into the cutaneous, the subcutaneous, and the mixed forms.

The cutaneous naevus, "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 naevi 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 naevi, the cutaneous variety shows little tendency to disappear, and it is especially persistent when associated with overgrowth of the epidermis and of the hairs—naevoid mole.

The _treatment_ of the cutaneous naevus is unsatisfactory, owing to the difficulty of removing the naevus without leaving a scar which is even more disfiguring. Very small naevi may be destroyed by a fine pointed Paquelin thermo-cautery, or by escharotics, such as nitric acid. For larger naevi, radium and solidified carbon dioxide ("CO_2 snow") may be used. The extensive port-wine stains so often met with on the face are best left alone.

The subcutaneous naevus 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 naevus 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 Naevus.—As its name indicates, the mixed naevus partakes of the characters of the other two varieties; that is, it is a subcutaneous naevus 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 naevoid 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.



Prognosis.—The rate of growth of the subcutaneous and mixed forms of naevi 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 naevus may become greatly enlarged, leading to the formation of a cavernous angioma.

Treatment.—In view of the frequency with which subcutaneous and mixed naevi 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 naevi 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 naevus, 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 naevoid 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 naevus with a fine-pointed thermo-cautery, with the object of starting at each point a process of cicatrisation which extends throughout the naevoid 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 naevus 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 anaesthetic is necessary. The current used should be from 20 to 80 milliamperes, 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 naevus, 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 naevus.

Excision is to be preferred for naevi 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 haemorrhage 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 naevus. 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 haemorrhage from injury or ulceration.



The treatment is conducted on the same lines as for naevus. 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 haemorrhage may follow a wound of the dilated vessels.



The condition may be treated by excision or by electrolysis. In excision the haemorrhage 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 naevus. 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 fasciae, 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.



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 oedema 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 vertebrae 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 haemorrhage takes place.



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 bursae, 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 haemorrhage 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 haemorrhage 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 haemorrhage 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 milliamperes, 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.



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 haemorrhage 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 vertebrae or the sternum, causing erosion of these bones. Pressure on the thoracic veins and on the air-passage causes cyanosis and dyspnoea. When the oesophagus 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 vertebrae (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.



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 coeliac 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 vertebrae 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.



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 oesophagus, 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 haemorrhage. 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 oedema 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 oedema 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 oedema 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 oedema 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.



CHAPTER XV

THE LYMPH VESSELS AND GLANDS

Anatomy and Physiology—INJURIES OF LYMPH VESSELS—Wounds of thoracic duct—DISEASES OF LYMPH VESSELS—Lymphangitis: Varieties—Lymphangiectasis—Filarial disease—Lymphangioma—DISEASES OF LYMPH GLANDS—Lymphadenitis: Septic; Tuberculous; Syphilitic—Lymphadenoma—Leucocythaemia—TUMOURS.

Surgical Anatomy and Physiology.—Lymph is essentially blood plasma, which has passed through the walls of capillaries. After bathing and nourishing the tissues, it is collected by lymph vessels, which return it to the blood stream by way of the thoracic duct. These lymph vessels take origin in the lymph spaces of the tissues and in the walls of serous cavities, and they usually run alongside blood vessels—perivascular lymph vessels. They have a structure similar to that of veins, but are more abundantly provided with valves. Along the course of the lymph trunks are the lymph glands, which possess a definite capsule and are composed of a reticulated connective tissue, the spaces of which are packed with leucocytes. The glands act as filters, arresting not only inert substances, such as blood pigment circulating in the lymph, but also living elements, such as cancer cells or bacteria. As it passes through a gland the lymph is brought into intimate contact with the leucocytes, and in bacterial infections there is always a struggle between the organisms and the leucocytes, so that the glands may be looked upon as an important line of defence, retarding or preventing the passage of bacteria and their products into the general circulation. The infective agent, moreover, in order to reach the blood stream, must usually overcome the resistance of several glands.

Lymph glands are, for the most part, arranged in groups or chains, such as those in the axilla, neck, and groin. In any given situation they vary in number and size in different individuals, and fresh glands may be formed on comparatively slight stimulus, and disappear when the stimulus is withdrawn. The best-known example of this is the increase in the number of glands in the axilla which takes place during lactation; when this function ceases, many of the glands become involuted and are transformed into fat, and in the event of a subsequent lactation they are again developed. After glands have been removed by operation, new ones may be formed.

The following are the more important groups of glands, and the areas drained by them in the head and neck and in the extremities.

Head and Neck.—The anterior auricular (parotid and pre-auricular) glands lie beneath the parotid fascia in front of the ear, and some are partly embedded in the substance of the parotid gland; they drain the parts about the temple, cheek, eyelids, and auricle, and are frequently the seat of tuberculous disease. The occipital gland, situated over the origin of the trapezius from the superior curved line, drains the top and back of the head; it is rarely infected. The posterior auricular (mastoid) glands lie over the mastoid process, and drain the side of the head and auricle. These three groups pour their lymph into the superficial cervical glands. The submaxillary—two to six in number—lie along the lower order of the mandible from the symphysis to the angle, the posterior ones (paramandibular) being closely connected with the submaxillary salivary gland. They receive lymph from the face, lips, floor of the mouth, gums, teeth, anterior part of tongue, and the alae nasi, and from the pre-auricular glands. The lymph passes from them into the deeper cervical glands. They are frequently infected with tubercle, with epithelioma which has spread to them from the mouth, and also with pyogenic organisms. The submental glands lie in or close to the median line between the anterior bellies of the digastric muscles, and receive lymph from the lips. It is rare for them to be the seat of tubercle, but in epithelioma of the lower lip and floor of the mouth they are infected at an early stage of the disease. The supra-hyoid gland lies a little farther back, immediately above the hyoid bone, and receives lymph from the tongue. The superficial cervical (external jugular) glands, when present, lie along the external jugular vein, and receives lymph from the occipital and auricular glands and from the auricle. The sterno-mastoid glands—glandulae concatinatae—form a chain along the posterior edge of the sterno-mastoid muscle, some of them lying beneath the muscle. They are commonly enlarged in secondary syphilis. The superior deep cervical (internal jugular) glands—from six to twenty in number—form a continuous chain along the internal jugular vein, beneath the sterno-mastoid muscle. They drain the various groups of glands which lie nearer the surface, also the interior of the skull, the larynx, trachea, thyreoid, and lower part of the pharynx, and pour their lymph into the main trunks at the root of the neck. Belonging to this group is one large gland (the tonsillar gland) which lies behind the posterior belly of the digastric, and rests in the angle between the internal jugular and common facial veins. It is commonly enlarged in affections of the tonsil and posterior part of the tongue. In the same group are three or four glands which lie entirely under cover of the upper end of the sterno-mastoid muscle, and surround the accessory nerve before it perforates the muscle. The deep cervical glands are commonly infected by tubercle and also by epithelioma secondary to disease in the tongue or throat. The inferior deep cervical (supra-clavicular) glands lie in the posterior triangle, above the clavicle. They receive lymph from the lowest cervical glands, from the upper part of the chest wall, and from the highest axillary glands. They are frequently infected in cancer of the breast; those on the left side also in cancer of the stomach. The removal of diseased supra-clavicular glands is not to be lightly undertaken, as difficulties are liable to ensue in connection with the thoracic duct, the pleura, or the junction of the subclavian and internal jugular veins. The retro-pharyngeal glands lie on each side of the median line upon the rectus capitis anticus major muscle and in front of the pre-vertebral layer of the cervical fascia. They receive part of the lymph from the posterior wall of the pharynx, the interior of the nose and its accessory cavities, the auditory (Eustachian) tube, and the tympanum. When they are infected with pyogenic organisms or with tubercle bacilli, they may lead to the formation of one form of retro-pharyngeal abscess.

Upper Extremity.—The epi-trochlear and cubital glands vary in number, that most commonly present lying about an inch and a half above the medial epi-condyle, and other and smaller glands may lie along the medial (internal) bicipital groove or at the bend of the elbow. They drain the ulnar side of the hand and forearm, and pour their lymph into the axillary group. The epi-trochlear gland is sometimes enlarged in syphilis. The axillary glands are arranged in groups: a central group lies embedded in the axillary fascia and fat, and is often related to an opening in it; a posterior or subscapular group lies along the line of the subscapular vessels; anterior or pectoral groups lie behind the pectoralis minor, along the medial side of the axillary vein, and an inter-pectoral group, between the two pectoral muscles. The axillary glands receive lymph from the arm, mamma, and side of the chest, and pass it on into the lowest cervical glands and the main lymph trunk. They are frequently the seat of pyogenic, tuberculous, and cancerous infection, and their complete removal is an essential part of the operation for cancer of the breast.

Lower Extremity.—The popliteal glands include one superficial gland at the termination of the small saphenous vein, and several deeper ones in relation to the popliteal vessels. They receive lymph from the toes and foot, and transmit it to the inguinal glands. The femoral glands lie vertically along the upper part of the great saphenous vein, and receive lymph from the leg and foot; from them the lymph passes to the deep inguinal and external iliac glands. The femoral glands often participate in pyogenic infections entering through the skin of the toes and sole of the foot. The superficial inguinal glands lie along the inguinal (Poupart's) ligament, and receive lymph from the external genitals, anus, perineum, buttock, and anterior abdominal wall. The lymph passes on to the deep inguinal and external iliac glands. The superficial glands through their relations to the genitals are frequently the subject of venereal infection, and also of epithelioma when this disease affects the genitals or anus; they are rarely the seat of tuberculosis. The deep inguinal glands lie on the medial side of the femoral vein, and sometimes within the femoral canal. They receive lymph from the deep lymphatics of the lower limb, and some of the efferent vessels from the femoral and superficial inguinal glands. The lymph then passes on through the femoral canal to the external iliac glands. The extension of malignant disease, whether cancer or sarcoma, can often be traced along these deeper lymphatics into the pelvis, and as the obstruction to the flow of lymph increases there is a corresponding increase in the swollen dropsical condition of the lower limb on the same side.

The glands of the thorax and abdomen will be considered with the surgery of these regions.

INJURIES OF LYMPH VESSELS

Lymph vessels are divided in all wounds, and the lymph that escapes from them is added to any discharge that may be present. In injuries of larger trunks the lymph may escape in considerable quantity as a colourless, watery fluid—lymphorrhagia; and the opening through which it escapes is known as a lymphatic fistula. This has been observed chiefly after extensive operation for the removal of malignant glands in the groin where there already exists a considerable degree of obstruction to the lymph stream, and in such cases the lymph, including that which has accumulated in the vessels of the limb, may escape in such abundance as to soak through large dressings and delay healing. Ultimately new lymph channels are formed, so that at the end of from four to six weeks the discharge of lymph ceases and the wound heals.

Lymphatic Oedema.—When the lymphatic return from a limb has been seriously interfered with,—as, for example, when the axillary contents has been completely cleared out in operating for cancer of the breast,—a condition of lymphatic oedema may result, the arm becoming swollen, tight, and heavy.

Various degrees of the conditions are met with; in the severe forms, there is pain, as well as incapacity of the limb. As in ordinary oedema, the condition is relieved by elevation of the limb, but not nearly to the same degree; in time the tissues become so hard and tense as scarcely to pit on pressure; this is in part due to the formation of new connective tissue and hypertrophy of the skin; in advanced cases there is a gradual transition into one form of elephantiasis.

Handley has devised a method of treatment—lymphangioplasty—the object of which is to drain the lymph by embedding a number of silk threads in the subcutaneous cellular tissue.

Wounds of the Thoracic Duct.—The thoracic duct usually opens at the angle formed by the junction of the left internal jugular and subclavian veins, but it may open into either of these vessels by one or by several channels, or the duct may be double throughout its course. There is a smaller duct on the right side—the right lymphatic duct. The duct or ducts may be displaced by a tumour or a mass of enlarged glands, and may be accidentally wounded in dissections at the root of the neck; jets of milky fluid—chyle—may at once escape from it. The jets are rhythmical and coincide with expiration. The injury may, however, not be observed at the time of operation, but later through the dressings being soaked with chyle—chylorrhoea. If the wound involves the only existing main duct and all the chyle escapes, the patient suffers from intense thirst, emaciation, and weakness, and may die of inanition; but if, as is usually the case, only one of several collateral channels is implicated, the loss of chyle may be of little moment, as the discharge usually ceases. If the wound heals so that the chyle is prevented from escaping, a fluctuating swelling may form beneath the scar; in course of time it gradually disappears.

An attempt should be made to close the wound in the duct by means of a fine suture; failing this, the duct must be occluded by a ligature as if it were a bleeding artery. The tissues are then stitched over it and the skin wound accurately closed, so as to obtain primary union, firm pressure being applied by dressings and an elastic webbing bandage. Even if the main duct is obliterated, a collateral circulation is usually established. A wound of the right lymphatic duct is of less importance.

Subcutaneous rupture of the thoracic duct may result from a crush of the thorax. The chyle escapes and accumulates in the cellular tissue of the posterior mediastinum, behind the peritoneum, in the pleural cavity (chylo-thorax), or in the peritoneal cavity (chylous ascites). There are physical signs of fluid in one or other of these situations, but, as a rule, the nature of the lesion is only recognised when chyle is withdrawn by the exploring needle.

DISEASES OF LYMPH VESSELS

Lymphangitis.—Inflammation of peripheral lymph vessels usually results from some primary source of pyogenic infection in the skin. This may be a wound or a purulent blister, and the streptococcus pyogenes is the organism most frequently present. Septic lymphangitis is commonly met with in those who, from the nature of their occupation, handle infective material. A gonococcal form has been observed in those suffering from gonorrhoea.

The inflammation affects chiefly the walls of the vessels, and is attended with clotting of the lymph. There is also some degree of inflammation of the surrounding cellular tissue—peri-lymphangitis. One or more abscesses may form along the course of the vessels, or a spreading cellulitis may supervene.

The clinical features resemble those of other pyogenic infections, and there are wavy red lines running from the source of infection towards the nearest lymph glands. These correspond to the inflamed vessels, and are the seat of burning pain and tenderness. The associated glands are enlarged and painful. In severe cases the symptoms merge into those of septicaemia. When the deep lymph vessels alone are involved, the superficial red lines are absent, but the limb becomes greatly swollen and pits on pressure.

In cases of extensive lymphangitis, especially when there are repeated attacks, the vessels are obliterated by the formation of new connective tissue and a persistent solid oedema results, culminating in one form of elephantiasis.

Treatment.—The primary source of infection is dealt with on the usual lines. If the lymphangitis affects an extremity, Bier's elastic bandage is applied, and if suppuration occurs, the pus is let out through one or more small incisions; in other parts of the body Klapp's suction bells are employed. An autogenous vaccine may be prepared and injected. When the condition has subsided, the limb is massaged and evenly bandaged to promote the disappearance of oedema.

Tuberculous Lymphangitis.—Although lymph vessels play an important role in the spread of tuberculosis, the clinical recognition of the disease in them is exceptional. The infection spreads upwards along the superficial lymphatics, which become nodularly thickened; at one or more points, larger, peri-lymphangitic nodules may form and break down into abscesses and ulcers; the nearest group of glands become infected at an early stage. When the disease is widely distributed throughout the lymphatics of the limb, it becomes swollen and hard—a condition illustrated by lupus elephantiasis.

Syphilitic lymphangitis is observed in cases of primary syphilis, in which the vessels of the dorsum of the penis can be felt as indurated cords.

In addition to acting as channels for the conveyance of bacterial infection, lymph vessels frequently convey the cells of malignant tumours, and especially cancer, from the seat of the primary disease to the nearest lymph glands, and they may themselves become the seat of cancerous growth forming nodular cords. The permeation of cancer by way of the lymphatics, described by Sampson Handley, has already been referred to.

Lymphangiectasis is a dilated or varicose condition of lymph vessels. It is met with as a congenital affection in the tongue and lips, or it may be acquired as the result of any condition which is attended with extensive obliteration or blocking of the main lymph trunks. An interesting type of lymphangiectasis is that which results from the presence of the filaria Bancrofti in the vessels, and is observed chiefly in the groin, spermatic cord, and scrotum of persons who have lived in the tropics.

Filarial disease in the lymphatics of the groin appears as a soft, doughy swelling, varying in size from a walnut to a cocoa-nut; it may partly disappear on pressure and when the patient lies down.

The patient gives a history of feverish attacks of the nature of lymphangitis during which the swelling becomes painful and tender. These attacks may show a remarkable periodicity, and each may be followed by an increase in the size of the swelling, which may extend along the inguinal canal into the abdomen, or down the spermatic cord into the scrotum. On dissection, the swelling is found to be made up of dilated, tortuous, and thickened lymph vessels in which the parent worm is sometimes found, and of greatly enlarged lymph glands which have undergone fibrosis, with giant-cell formation and eosinophile aggregations. The fluid in the dilated vessels is either clear or turbid, in the latter case resembling chyle. The affection is frequently bilateral, and may be associated with lymph scrotum, with elephantiasis, and with chyluria.

The diagnosis is to be made from such other swellings in the groin as hernia, lipoma, or cystic pouching of the great saphenous vein. It is confirmed by finding the recently dead or dying worms in the inflamed lymph glands.

Treatment.—When the disease is limited to the groin or scrotum, excision may bring about a permanent cure, but it may result in the formation of lymphatic sinuses and only afford temporary relief.

Lymphangioma.—A lymphangioma is a swelling composed of a series of cavities and channels filled with lymph and freely communicating with one another. The cavities result either from the new formation of lymph spaces or vessels, or from the dilatation of those which already exist; their walls are composed of fibro-areolar tissue lined by endothelium and strengthened by non-striped muscle. They are rarely provided with a definite capsule, and frequently send prolongations of their substance between and into muscles and other structures in their vicinity. They are of congenital origin and usually make their appearance at or shortly after birth. When the tumour is made up of a meshwork of caverns and channels, it is called a cavernous lymphangioma; when it is composed of one or more cysts, it is called a cystic lymphangioma. It is probable that the cysts are derived from the caverns by breaking down and absorption of the intervening septa, as transition forms between the cavernous and cystic varieties are sometimes met with.

The cavernous lymphangioma appears as an ill-defined, soft swelling, presenting many of the characters of a subcutaneous haemangioma, but it is not capable of being emptied by pressure, it does not become tense when the blood pressure is raised, as in crying, and if the tumour is punctured, it yields lymph instead of blood. It also resembles a lipoma, especially the congenital variety which grows from the periosteum, and the differential diagnosis between these is rarely completed until the swelling is punctured or explored by operation. If treatment is called for, it is carried out on the same lines as for haemangioma, by means of electrolysis, igni-puncture, or excision. Complete excision is rarely possible because of the want of definition and encapsulation, but it is not necessary for cure, as the parts that remain undergo cicatrisation.