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C Couinaud

Publications and source records attributed to C Couinaud.

At least 19 recordsLinked to original sources
PubMed1999

Liver anatomy: portal (and suprahepatic) or biliary segmentation.

BACKGROUND/AIMS: In liver anatomy and surgery, is portal and hepatic vein segmentation (French segmentation) to be preferred over arteriobiliary segmentation (Healey and Schroy, North American segmentation)? METHODS: Several embryological arguments and an analysis of anatomical data from a personal collection of 110 vasculobiliary casts were made. RESULTS: Embryological arguments: Portal vein branching appears first, arteriobiliary branching secondly follows the portal vein distribution. Segment II (the left lateral sector) is the development of the right lateral embryological lobe. The umbilical vein enters the left portion of the middle embryological lobe, forming segment IV on the right and segment III on the left: this is the left paramedian sector. So the left portal fissure (between left and middle lobes) transversally crosses the classical left lobe, which is not a portal unit. Segment VI is a late secondary prominence of segment VII, reaching the anterior margin of the liver only in man. Anatomical arguments: hepatic vein segmentation must be added to portal segmentation; the academic left lobe is the left hepatic vein sector, and the left hepatic fissure separates the classical right and left lobes. Portal vein segmentation must be preferred: portal vein duplication of branches of first order occurs only in 23.5% of the cases, while arteriobiliary duplication of first-order branches is noted in 50% of the livers, portal segmentation being much simpler. CONCLUSIONS: Portal and hepatic vein segmentation seems to be much more accurate.

Animals↗
PubMed1998

[Dorsal sector of the liver].

The dorsal sector extends in front and to the sides of the inferior vena cava, separating the caval axis from the main liver (excepting superiorly the entrance of the main hepatic veins into the vena cava). The two elements, dorsal sector and retro-hepatic portion of the vena cava, actually make a single unit. It is made of two segments: left (segment I) larger than the Spieghel lobe, right (segment IX) incorporated in the posterior surface of the right liver. The "caudate process" is not a peculiar element: it is nothing else than the inferior margin of segment IX: the breadth gives information on the size of segment IX. The dorsal sector is the midportion of the posterior liver, it is absolutely independent of the right and left livers separated by the main portal fissure. Portal pedicles are numerous and ascendant, they arise from the posterior margin of the transverse portal arch (from right to left: segment VII vein, right lateral vein, right portal vein, left portal vein, segment II vein). The size of the dorsal sector is variable, and can be appreciated by an antero-posterior index. A voluminous sector may be a problem for the surgeon. Segment IX can be divided in three subsegments: IXb under the interval between the right superior hepatic vein and the middle hepatic vein (longer branches can ascend and supply a small portion of the upper surface in front of the vena cava), IXc under the very broad right superior vein, and posteriorly IXd, linked to segment VII. Only segment I and subsegment IXb receive branches from the right and from the left livers. Hepatic veins enter directly the caval axis, some enter the main hepatic veins. The dorsal sector is a large anastomosis between efferent veins and the vena cava. Anteriorly segment I is in contact with segment IV but also with segment VIII, subsegments IXb and IXc with segment VIII and IXd with segment VII. The fissural limit is difficult to locate. Posteriorly division of the triangular and coronary ligaments, section of the dorsal hepatic veins, the right middle and inferior veins allow separation of the liver from the posterior abdominal wall and the inferior vena cava, so the surgeon can reach the dorsal sector. A remarkable error has been commited when the main hepatectomies were described: the dorsal sector was not known and the caudate lobe was considered as a part of the left liver. Actually the dorsal liver is a separate entity covering the inferior vena cava which has no connexion with the main liver; when the main portal fissure is opened up to the anterior surface of the vena cava, the dorsal sector is opened vertically. Interruption of the pedicles must also be considered. For example, in a left hepatectomy, the left portal pedicle is divided, all the left branches for subsegment IXb (which will be preserved) are interrupted; but the left branches from the right portal pedicle are not interrupted and will bleed when the dorsal sector is divided. When splitting the liver for transplantation, some difficulties can occur, especially with the right transplant. A main practical interest is the possible propagation to the dorsal ducts of hilar carcinoma.

Hepatectomy↗
PubMed1994

[Intrahepatic anatomy. Application to liver transplantation].

In transplantation of the whole liver, the variable shape of the organ can exceptionally be the source of difficulties, as in the rare cases of situs inversus. Arterial variants may be the source of great difficulties. Among the biliary variants, the low junction of the right and left hepatic ducts in the main portal pedicle, and especially the cysto-hepatic ducts (entrance of a right duct into the gallbladder or the cystic duct) are particularly important, with a frequency ranging from 2 to 15% of the cases. Right liver--left liver, or right liver--left lobe bipartition is now a well controlled technique. Right lobe, left lobe bipartition should never be performed. The left hepatic vein is attributed to the left transplant (left liver or left lobe). In case of duplication of the left vein, the terminal portion of the middle vein is attributed to the left transplant, and the continuity of the middle vein with the inferior vena cava must be reconstructed. The middle vein is always attributed to the right transplant. When the portal bifurcation is missing, usually bipartition is impossible. When the right portal vein is duplicated, the portal stem is attributed to the right liver. Duplications of right and left arteries and ducts make difficulties. A thorough preoperative investigation is necessary in case of a living donor. Cholangiography and arteriography on the back table are essential to achieve an ex vivo bipartition. The surgeon then disposes of three manoeuvres: resection of segment IV, attribution of a short segment of the main duct on the side of a biliary duplication, attribution of the main hepatic artery (or the celiac axis) on the side of a left transplant (left liver or left lobe) is possible in 86% of cases, ex vivo is possible in 95. 70% of cases. Tripartition of the liver is not yet a controlled technique.

Hepatic Artery↗
PubMed1993

Controlled liver splitting for transplantation in two recipients: technique, results and perspectives.

A technique of controlled liver splitting for transplantation in two recipients is proposed, based on a full anatomical assessment of the graft including arteriography and cholangiography on the back-table. Using eight livers, 16 patients received a graft: right liver (eight patients), left lobe (four) or left liver (four). Twelve patients required urgent or very urgent transplantation. Anatomical assessment of the graft demonstrated a portal bifurcation in all cases, a common trunk of the left and middle hepatic veins in five, a right biliary duplication in three and duplication of the left branch of the middle hepatic artery in one. After revascularization of the graft, bleeding was greater in patients with a right graft, particularly if the middle hepatic vein had been ligated. The main postoperative complications were hepatic artery thrombosis (four cases), biliary complications (four), portal vein thrombosis (two), haematoma (two) and abscess (two). No primary non-function of the graft was observed. The postoperative survival rate was 75 per cent. The four patients in whom transplantation was not considered urgent are still alive. The immediate survival rate of the grafts was 69 per cent. These results compare favourably with those in the literature. In spite of the technical, logistical and ethical problems raised by this technique, the results suggest that controlled liver splitting for transplantation in two recipients may in the future significantly improve the feasibility of liver transplantation.

Adolescent↗
PubMed1993

[A "scandal": segment IV and liver transplantation].

Partition right-left lobes keeps segment IV in continuity with the right liver, but interrupts its portal elements which arise from the left portal pedicle. A precise anatomical investigation shows that the venous inflow is totally interrupted. In 12.15% of the cases (n = 107) the biliary duct from segment IV enters close to the upper biliary confluent, into the confluent or the main duct, and can be preserved in such a bipartition; in all other cases the segment is no longer in function and doomed to atrophy. In 10.75% of the livers (n = 99), the segmental artery comes from the right hepatic stem, and the segment is correctly vascularized; but in most cases interruption of both the artery and the portal branches leads to immediate necrosis, which may be lethal. Preservation of both artery and biliary ducts is possible in only 2.15% of the cases (n = 93 casts with correct injection of arteries and ducts). Consequently the partition right-left lobes is possible in only a few cases: cholangiography and arteriography detect the favourable dispositions. In all other cases such partition is forbidden. Procurement of the left lobe from a living donor with preservation of segment IV is rarely possible, such cases being detected by a thorough pre-operative vasculo-biliary investigation: the left lobe is harvested, and segment IV left in situ (2.15% of the cases). Usually the prospective of rapid necrosis or secondary atrophy commands resection of the segment.(ABSTRACT TRUNCATED AT 250 WORDS)

Biliary Tract Surgical Procedures↗
PubMed1993

[Absence of portal bifurcation].

Since the first description in 1957, absence of the portal bifurcation has been reported by four different teams, which makes a total of 5 cases and a frequency of 1.90%. Serious complications may occur postoperatively, and this anomaly should be systematically detected. There is a huge portal ring: the main vessel enters the liver, looking like a large right paramedian vein, turns to the right within the parenchyma, reaches the umbilical fissure to send the usual branches of REX' recessus, and ends as a terminal branch for the caudate lobe. The right lateral vein appears as a collateral. Numerous anterior and posterior branches supply segments IV, V and VIII. Two main facts: the portal ring turns around the axis of the middle hepatic vein, which is in the center of the ring. There is a rupture in the portal triad of the left portal pedicle: the vein is intra-hepatic, the artery and biliary duct lie normally in the hilum. The detection of this anomaly should always be done by portography or ultra-sonography. When operating, it is easily detected: there is no portal bifurcation and the left portal vein is missing. The main difficulty is to perform a right hepatectomy. After total vascular by-pass, the portal system is skeletonized and resection achieved. Another solution is to interrupt the portal stem deep in the hilum, divide the main portal fissure along the right margin of the middle hepatic vein and cut the transversal portion of the portal ring.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Bisection of the liver for transplantation. Simplification of the method].

Blind bipartition of a whole liver to obtain two transplants is problematic, because of frequent vasculo-biliary duplications, especially arterial (mainly on the left) and biliary (mainly on the right) duplications. Arteriography and cholangiography on the back table are necessary to obtain a map of the arterial and biliary distributions without injuring the vessels of the biliary ducts enclosed in the vasculo-biliary sheaths. The surgeon may use three special maneuvers: resection of segment IV when the arterio-biliary duplication involves segment IV; attribution of the common hepatic artery on the side of the arterial duplication (frequent on the left); attribution of a short segment of the common hepatic duct on the side of a biliary duplication (frequent on the right). In an anatomical study of 93 vasculo-biliary casts, the following results were obtained: in 4 cases: bipartition not possible; in 22 cases: "ideal" bipartition (no duplication); in 57 cases: partition right-left livers: in 37 cases 1 maneuver, in 19 cases 2 maneuvers, in 1 case 3 maneuvers; in 10 cases: partition right liver-left lobe: in 2 cases 1 maneuver, in 8 cases 2 maneuvers. We report 8 bipartitions and 16 transplantations (10 children and 6 adults). The duplications we noted do not differ statistically from those reported in our former anatomical study. Survival of the patients (100% in usual cases, 66% in case of extreme emergency or terminal hepatic insufficiency) and survival of the transplants (68,75%) do not differ either from those noted in other transplantation methods. Complications, especially arterial thrombosis, were within the same statistical ranges.(ABSTRACT TRUNCATED AT 250 WORDS)

Dissection↗
PubMed1989

[An unknown syndrome: acute zinc deficiency in the elderly in a surgical milieu].

Old people often present a chronic depletion in zinc. Any stress increases zinc consumption and zinc loss through the kidneys; acute depletion then appears. Anorexia is usual, psycho-neurological troubles induce to a wrong diagnostic of sudden senility or psychiatric disorder. Altered taste and a low blood level of zinc confirms the diagnostic. Zinc administration, usually per os, leads to a prompt recovery. 18 patients have been recorded; acute depletion occurred after infection or any ordinary surgical intervention.

Acute Disease↗
PubMed1989

Exposure of the left hepatic duct through the hilum or in the umbilical of the liver: anatomic limitations.

Anastomosis to the left hepatic duct approached by dissecting the hilar plate is the most reliable method of drainage of the left side of the liver in that longitudinal incision of the left hepatic duct allows a long cholangiojejunostomy. However, the anatomy is not satisfactory in 30% of cases for adequate drainage of the left side of the liver. To further clarify this surgically important area, 107 vasculobiliary casts were reviewed with regard to the anatomy and relationship between the left biliary ductal and left portal venous systems. In cases in which anatomy is unfavorable for adequate drainage by anastomosis to the left hepatic duct in the hilum, several options are available. The anterior portion of the main portal fissure may be opened to gain wide access to the superior aspect of the biliary plate and reach a posterior duct that is more suitable for anastomosis. An anastomosis to an anterior duct may also be possible with this approach. If left portal ducts are inaccessible by division of the main portal fissure because of a retroportal location, then an anastomosis in the anterior portion of the umbilical fissure may give adequate drainage. Therefore a cholangiogram is imperative before any anastomosis in the hilum or the anterior portion of the umbilical fissure.

Anastomosis, Surgical↗
PubMed1988

The parabiliary venous system.

The parabiliary venous system originates from the pancreatico-duodenal and pyloro-duodenal veins, runs along the common bile-duct and the hepatic artery, and divides in the liver hilum into a venous network within the hilar plate. Embryologically, this system, apparently independent of the portal vein, develops together with the bile-ducts and the hepatic artery: these three structures are within the substance of the vasculo-biliary sheaths, and the whole complex invades the liver well after the distribution of the portal vein has been established. It should be pointed out that segments I and IV also appear rather late. Seventy-four specimens with injection of the system have been studied. The hilar plexus sends branches to the veins of the segments adjacent to the hilum. Some vessels directly supply the inferior surface of the quadrate lobe or the caudate lobe, or the left lobe. In 46.50% of specimens, part of the cystic veins are anastomosed with the parabiliary system.

Biliary Tract↗