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separated from it by the fossa for the ductus venosus. The
groove leads down to the gastric impression on the inferior surface of the left lobe (Fig. 938), and, hen in the body, lies in contact with the prominent right or anterior margin of e oesophageal orifice of the diaphragm (see p. 1152 and Fig. 912), sometimes also ith the oesophagus itself.
Facies Inferior.—The inferior or visceral is an irregular, obliquely sloping rface (Fig. 938), which looks downwards, posteriorly, and to the left, and rests
on the stomach, lesser omentum, intestines, and right kidney. The division
Inferior vena cava in its fossa
End of right suprarenal vein
Right end of caudate process
Uncovered area of right lobe
Attachment of right
ts on the superior surface of the stomach, in front of the cardia; also on the sser curvature with its attached lesser omentum. The part which rests upon e anterior surface of the stomach is rendered concave by the pressure of that gan (Fig. 938), and is known as the impressio gastrica ; whilst the portion to the ht of this, being free from the pressure of the stomach, projects backwards over e lesser curvature against the lesser omentum in the form of a smooth rounded ominence, and is known as the tuber omentale.
The inferior surface of the right lobe may be divided into two portions by the e of the gall-bladder, which extends forwards in its fossa to the anterior sharp Ergin of the liver (Fig. 936).
(a) To the left of the line of the gall-bladder are found from before backwards :e lobus.quadratus, porta hepatis, and processus caudatus. The quadrate lobe is of an oblong shape, the antero-posterior diameter being the greatest. Its face is generally concave, and is related to the pylorus and the adjacent parts of the stomach 3 duodenum, when the former is distended. When the stomach is empty, however, the
Onit pylorus usually lies beneath the right portion of the left lobe, and the superior part of the duodenum lies beneath the quadrate lobe, the transverse colon also coming in contact with it Test anteriorly (Fig. 938).
Pations (b) The surface to the right of the gall-bladder, which is more extensive than
See the that on its left, is entirely occupied by three impressions, produced by the under
li lying viscera-namely: (1) The impressio colica lies in front and to the right of
ietei the gall-bladder. It is formed by the right flexure of the colon and the beginning of the transverse colon. (2) Behind this is the impressio renalis, larger than the
F, 07: preceding, which is produced by the superior half or two-thirds of the right kidney. It is placed behind the colic impression just as the kidney itself is placed behind
i Fi the colon. The superior end of the renal impression is frequently devoid of ne the peritoneum (Fig. 938), that is to say, the “uncovered area” of the right lobe
a. Th extends down over the impression for a little way. This impression is very deep,
a similar and accommodates nearly the whole thickness of the kidney. In many hardened
Azin, in specimens it would appear to belong more to the posterior part of the parietal surface than to the inferior or visceral surface. (3) To the medial side of the renal partit impression, and near the neck of the gall-bladder, is placed the narrow impressio
- Low thi duodenalis, which lies in contact with the descending part of the duodenum down to the point at which it is crossed by the colon.
Surface Markings of the Liver.—The limits even of the normal liver are very variable, but, taking the average condition in the male, they may be marked out
Tre the E. on the anterior surface of the body by the following method :—Three points are determined—a) half an inch (12.5 mm.) below the right nipple; (b) half an inch (12.5 mm.) below the right margin of the thorax (or below the tip of the tenth rib); e and (c) one inch (25 mm.) below the left nipple. If these points are joined by three lines, slightly concave towards the liver, they will give the outline of the organ with sufficient accuracy for all ordinary purposes. (For variations in position see below.)
To state the matter somewhat more in detail :--If the two “nipple points” (a) and (c) be joined by a line, slightly convex upwards on each side, but a little depressed at the centre corre sponding to the position of the heart, and crossing the inferior end of the sternum about the level of the seventh cartilage, it will mark the superior limit. A line, convex upwards, from the right nipple point (a) to the subcostal point (6) will indicate the right limit, while the inferior limit is marked by a line, convex downwards, drawn from the subcostal point (b) to the left nipple point (c), and passing through a point half-way between the umbilicus and the inferior end of the body of the sternum, in the median line.
The line indicating the superior limit of the liver is elevated on each side, corresponding to the cupolæ of the diaphragm, and depressed in the centre beneath the heart. On the right side where highest, namely, about one inch (25 mm.), medial to the mammary line, it reaches during expiration to the superior border of the fifth rib; on the left side it is one-half to three-quarters of an inch (12 to 18 mm.) lower; and it crosses behind the sternum at the level of the sixth sternocostal junction-or sometimes lower. It must be remembered, however, that, whilst the liver reaches up to the levels just given, it does so only at the highest part of its convex parietal surface, and is separated from the ribs all round by the thin lower margin of the lung (which extends down between the chest wall and diaphragm to the sixth rib in front, to the eighth in the midlateral line, and to the level of the tip of the spine of the tenth thoracic vertebra behind), so that, in percussing over the liver, its dulness is obscured by the resonance of the lungs above these points.
From the back, the superior margin of the liver rises as high as to the superior margin of the eighth rib or to the inferior margin of the scapula on the right side. On the left, it rises to the inferior margin of the eighth rib, and terminates about an inch medial to the inferior angle of the scapula.
The inferior margin slopes upwards along the eleventh rib of the right side, along a line leading to the superior part of the tenth thoracic vertebra. On the right side the liver extends verticalls in the mid-axillary line from the sixth to the eleventh ribs.
Variations in Size, Form, and Position.-Few organs will be found to vary more in size in different bodies than the liver; these variations, however
, are very frequently to be looked upon as pathological. But even the normal, healthy liver may vary in weight from 48 to 58 ounces I in the adult male, and from 40 to 50 ounces in the female.
Variations in form and position doubtlessly take place physiologically, as a result of the conditions of fulness or emptiness of the adjacent viscera ; for, though the liver, like the other salid abdominal organs, has an intrinsic shape of its own, this is capable of modification within certain limits by the varying pressure of the surrounding parts. Thus, distension of the stomach, oro a portion of the transverse colon lying in the stomach chamber, may push the liver over to the right, so that it may hardly reach the median plane, and at the same time it increases its vertical
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epth. On the other hand, a distended state of the small intestines, with a contracted stomach ad colon, may have the opposite effect, flattening it from below upwards and enlarging it in ne transverse direction.
Variations in form and position due to malformations of the thoracic framework, either connital or acquired, are very common, particularly in females as a result of tight-lacing, which esses the lower ribs inwards. Sometimes in these cases the constriction of the waist lies elly below the liver
. The organ is then forced up against the diaphragm, filling its whole vault, I extending across to the left abdominal wall, where its left margin may lie in the interval ween the diaphragm and the spleen. But more commonly it would seem that the liver is ght by the constriction : its upper part is then closely pressed into the vault of the diaphragm, ch, owing to the narrowing of the thorax, is unable to accommodate the whole organ, so
its inferior part is crushed down for a considerable distance into the umbilical zone of the men (Fig. 918, p. 1167), particularly on the right side. Often, too, a wide, tongue-like ess (the so-called “Reidel's lobe”) descends from the inferior margin, lateral to the gall, der. This process, which when very large may reach to the iliac crest, is sometimes found en, although more common in women, and is liable to be mistaken for a tumour. A somesimilar process occasionally descends from the left lobe. gain, in apparently healthy bodies the liver may extend up on the right side almost to the i rib; whilst in other cases it may be as low as the sixth rib, or even lower. Nor is it particularly in females—to find the anterior border projecting two or three inches (5:0 to 752 elow the margin of the thorax on the right side (Fig. 918, p. 1167). ference should be made here to certain grooves often seen on the liver. Some of these are running obliquely low down at the right side where the liver is in contact with the ribs ; re particularly common in females, and are due to the pressure of the ribs resulting from acing: Grooves of a different kind are found at the superior part of the parietal surface; the liver is in contact with the diaphragm ; these usually run radially, that is, in the on of the muscular fibres of the diaphragm, and are apparently produced by a wrinkling, ular contraction, of the diaphragm. At least, ridges of the diaphragm are found lying in oves, and these ridges or wrinkles would seem to be responsible for the production of the
lly, the liver may present certain congenital irregularities in the direction of additional nd lobes, which reproduce the conditions found in the higher apes, and are very ly present in the fætus (Thomson). Or the liver may be divided up into a large number ct lobes, as in most other animals. ges in position have been already referred to in connexion with variations in form ; d only be added here that the liver ascends and descends at every expiration and inspiraectively, and that it also descends, but very slightly, in changing from the reclining to
posture. Occasionally, without any evident cause, the liver and diaphragm are found a higher or lower position than usual. ion of the Liver. -At first sight it is not easy to understand the means by which maintains its position in the abdomen (and the same remark applies, perhaps, to other ominal organs). The falciform ligament gives it no support, as it is quite lax when dy. Nor can it be said that its vessels, except perhaps the hepatic veins, assist. on considering the conditions under which the viscera are placed in the abdominal problem becomes less difficult. domen is a closed cavity, with a firm framework to its superior part, a tightly stretched
for its roof, and muscular walls all round. Into the concavity of this roof the parietal the liver is fitted with perfect accuracy, so that the two are in absolute contact, and eparated without producing a vacuum, unless some other structure is in a position to ce. But there is hardly any other viscus movable enough to pass up over the front r into the vault of the diaphragm, so that atmospheric pressure alone is probably retain the organ in situ, as in the case of the shoulder joint. In addition, the abdominal always in a condition of tonic contraction or “tone," which gives rise to an intra
This is effective in all directions, and consequently there is a considerable all the abdominal walls. The liver, being in absolute contact with the roof, may be
part of this wall, and it is consequently affected by this pressure which helps to Add to this, the support which the organ receives from the intestines, the stomach, creas; from the coronary and triangular ligaments ; from the connexion of the back of be by areolar tissue to the diaphragm ; and, finally, from the inferior vena cava 1 the liver and sending its hepatic veins forwards to all parts of the organ, just
in itself is firmly attached to the margins of the caval orifice in the central tendon ragm, and we will probably find sufficient cause for the maintenance of the organ a in the abdominal cavity. n to Peritoneum.—The relation of the liver to the peritoneum is someex in its details. The greater part of the liver is covered with perining the tunica serosa, but there is an area of some size upon its superior r aspects where it is directly in contact with the diaphragm, and round
of this area the peritoneum passes from liver to diaphragm. This is he bare area, and the peritoneum around this area is known as the coronarium (coronary ligament). Further, the liver is attached to the
anterior portion of the diaphragm, and to the abdominal wall as low as to the umbilicus by a fold of peritoneum which is known as the ligamentum falciforme. This fold runs forwards from and is continuous with the folds of peritoneum which limit the bare area, and the whole forms a sort of mesentery or meso-hepaticum.
The peritoneum is also reflected off from the margins of the porta hepatis and from the fossa for the ductus venosus, and passes thence to the lesser curvature of the stomach and the first part of the duodenum, forming the omentum minus, The liver may, in fact, be regarded as lying inside a peritoneal fold which stretches from the lesser curvature of the stomach below to the diaphragm and anterior abdominal wall above. This fold is embryologically the ventral mesentery of the stomach, or ventral meso-gastrium, and its original simple character has become complicated by the growth of the liver within it and by the rotation which the stomach undergoes to the right side at its inferior part.
The various ligaments of the liver are as follows:
(1) Ligamentum Falciforme Hepatis.- The falciform ligament of the liver is a crescentic fold of peritoneum, which is attached by its convex border to the inferior surface of the diaphragm, and to the anterior abdominal wall (an inch or more to the right of the median plane) to within a short distance (1 to 2 inches, 2-5 to 5 cm.) of the umbilicus. Its concave border is attached to the superior and anterior aspects of the liver; below this level it presents a free rounded edge, stretching from near the umbilicus to the umbilical notch of the liver, and it contains within its layers a stout fibrous cord called the round ligament.
Near the posterior part of the superior surface of the liver the two layers of which the falciforn ligament is composed separate, and enclose a triangular area on the posterior surface, in front of the superior end of the vena cava, uncovered by peritoneum. Traced backwards, the right laver passes into the superior layer of the coronary ligament, the left into that of the left triangular ligament. It is the remains of a part of the ventral mesentery of the embryo, and has po supporting or suspensory action on the liver of the adult.
(2) Ligamentum Coronarium Hepatis.---The coronary ligament consists of the laver of peritoneum which are reflected from the liver to the diaphragm at the margins of the uncovered area of the right lobe. The name of right triangular ligament has been given to its pointed right extremity (Fig. 938).
The coronary ligament consists of a superior and an inferior layer. The superior is formed by the prolongation to the right of the right layer of the falciform ligament. The inferior layer is formed by the continuation of the inferior layer of the right triangular ligament to the left side, and by the reflection from the margin of the caudate lobe by the side of the inferior vena cava (see Fig. 938).
(3) Ligamentum Triangulare Dextrum. --The right triangular ligament (0.T. right lateral ligament) is merely the pointed right extremity of the coronary ligament, wher the superior and inferior layers become continuous with one another.
(+) Ligamentum Triangulare Sinistrum.---The left triangular ligament (0.T. left lateral ligament) is a considerable triangular fold, continuous with the left laver of the faleiform ligament, which is attached by one border to the superior surface of the left lote near its posterior border, and by the other to the diaphragm, for a distance of several inches as a rule.
Its attachment to the diaphragm lies nearly altogether to the left of the asophageal orif r. and about i inch (18 mm.) anterior to the plane of this opening.
Two other structures, termed ligaments, are not peritoneal folds, but obliterated blond vessels, namely the ligamentum teres hepatis or round ligament and the liganiente venosum (drantii).
(3) Ligamentum Teres Hepatis. — The round ligament of the liver is a stout tinus hand which passes from the umbilicus, backwards and upwards, within the ine marzo the faleijerm ligament, to the umbilical notch of the liver, and thenee upwaris » backwards in the umbilical fossa, to join the left branch of the portal rein. I: is :) remains of the left umbilical rein, which, before birth, carries the arterial blood from the placenta to the body of the fætus (Fig. 85).
16) Ligamentum Venosum Arantii. — The venous ligament of Arantius (O.T. obliter ated ductus venosus) is a slender tiomus cord, which passes from the left tranch of the portal vein, nearly opisite the attachment of the round ligament, upwaris in the fin
s its name, to be connected with the inferior vena cava as it leaves the liver. fætus this structure is a considerable vessel, which conveys some of the blood t to the porta hepatis by the left umbilical vein directly backwards to the vena At the time of birth the ductus venosus and umbilical vein cease to carry blood, vities become obliterated, and they are converted into fibrous cords. Omentum Minus.—The lesser omentum is a fold of peritoneum which extends e liver to the lesser curvature of the stomach and to the duodenum. attached, above, to the margins of the porta hepatis, and also to the bottom of the - the ductus venosus. Below, it is connected to the lesser curvature of the
where its two layers separate to enclose that organ, and also to the upper border uodenum for an inch or more beyond the pylorus. Between its layers, close to or free border, are contained the bile duct, the hepatic artery, the portal vein, and es and lymph vessels passing to and from the porta hepatis (Fig. 939). Its irt is wide, but it is narrow at each end. Of the two ends, the right is free, and
7th costal cartilage 7th costal cartilage
Lig. triangulare sinistrum „Diaphragm Fundus Esophagus Lig. gastrolienale
Pars pylorica Ductus cysticus
Omentum minus Peritoneum (cut edge)
Commencement of duodenum
Duodenum pars superior
Fig. 939.—THE LESSER OMENTUM.
the liver has been removed, and also the anterior layer of the hepato-duodenal ligament.
The view is taken looking upwards as well as backwards.
the liver to the duodenum, forming the anterior boundary of the foramen he left end is very narrow, and is attached to the diaphragm between the
caval openings. The portion of the lesser omentum passing between the mach is known as the ligamentum hepatogastricum; that between the liver um is called the ligamentum hepatoduodenale. -n from the liver to the superior part of the right kidney (a portion of the the coronary ligament) is termed the hepato-renal ligament.
rea” of the liver is triangular in shape, and measures about 3 inches vertical extent, and some 5 inches transversely. It is in contact ragm, a portion of the right suprarenal gland, and the inferior is bounded above and below by the superior and inferior folds of gament, and on the left by the attachment of peritoneum to the audate lobe. It is prolonged upwards for a short distance on the
of the liver, in front of the inferior vena cava, between the layers ligament as they diverge from one another.