The infrapyloric artery and cephalic pancreatoduodenectomy with pylorus preservation: preliminary study

Summary Cephalic pancreatoduodenectomy (CPD) with pylorus preservation has been suggested to improve the functional and nutritional result of surgery. At operation, the first two centimeters of the duodenum are preserved, the vascular arch of the lesser gastric curvature is saved and the right gastroepiploic artery is resected at its origin. The aim of this study on 15 fresh cadavers was to determine the origin of the vascularization of the remaining duodenum and also the possibilities of preserving an optimal vascularization after CPD and pylorus preservation. All of the arteries supplying the remaining duodenum and arising either from the right gastric artery or the right gastroepiploic artery were identified. The distances between the origin of the infrapyloric artery and the termination of the gastroduodenal artery on the cranial and ventral pancreaticoduodenal artery and the left gastroepiploic artery were measured. At CPD with pylorus preservation, the study demonstrated that: 1) the cranial side of the remaining duodenum remains vascularized in 80% of the cases by one or two supraduodenal branches coming from the right gastric artery; 2) ligation of the right gastroepiploic artery eliminates all vascular supply to the caudal side of the remaining duodenum in almost half of the cases; 3) in these cases, the dissection of the bifurcation of the gastroduodenal artery and the vascular section beyond the origin of the infrapyloric artery allowed a direct vascular supply to the remaining duodenum to be preserved.This work was presented at the French Section of the European Association of Clinical Anatomy meeting, Bobigny, France, 1992     

Missense mutation in a von Willebrand factor type A domain of the alpha 3(VI) collagen gene (COL6A3) in a family with Bethlem myopathy

The Bethlem myopathy is a rare autosomal dominant proximal myopathy characterized by early childhood onset and joint contractures. Evidence for linkage and genetic heterogeneity has been established, with the majority of families linked to 21q22.3 and one large family linked to 2q37, implicating the three type VI collagen subunit genes, COL6A1 (chromosome 21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes. Mutations of the invariant glycine residues in the triple-helical domain-coding region of COL6A1 and COL6A2 have been reported previously in the chromosome 21-linked families. We report here the identification of a G-->A mutation in the N-terminal globular domain-coding region of COL6A3 in a large American pedigree (19 affected, 12 unaffected), leading to the substitution of glycine by glutamic acid in the N2 motif, which is homologous to the type A domains of the von Willebrand factor. This mutation segregated to all affected family members, to no unaffected family members, and was not identified in 338 unrelated Caucasian control chromosomes. Thus mutations in either the triple-helical domain or the globular domain of type VI collagen appear to cause Bethlem myopathy.      

doublecortin is the major gene causing X-linked subcortical laminar heterotopia (SCLH)

Subcortical laminar heterotopia (SCLH), or 'double cortex', is a cortical dysgenesis disorder associated with a defect in neuronal migration. Clinical manifestations are epilepsy and mental retardation. This disorder, which mainly affects females, can be inherited in a single pedigree with lissencephaly, a more severe disease which affects the male individuals. This clinical entity has been described as X- SCLH/LIS syndrome. Recently we have demonstrated that the doublecortin gene, which is localized on the X chromosome, is implicated in this disorder. We have now performed a systematic mutation analysis of doublecortin in 11 unrelated females with SCLH (one familial and 10 sporadic cases) and have identified mutations in 10/11 cases. The sequence differences include nonsense, splice site and missense mutations and these were found throughout the gene. These results provide strong evidence that loss of function of doublecortin is the major cause of SCLH. The absence of phenotype-genotype correlations suggests that X-inactivation patterns of neuronal precursor cells are likely to contribute to the variable clinical severity of this disorder in females.      

MR imaging of posteromedial and posterolateral stabilisers of the knee: anatomic basis and patterns of lesions in knee injuries

Summary The angular points are the ligamentous and tendinous structures that reinforce the posteromedial and posterolateral capsule of the knee and share in fixation of the posterior horns of the menisci. They are often damaged in acute injuries and this is usually associated with ruptures of the cruciate and collateral ligaments and may add to the degree of laxity. We describe the normal appearance of these structures in terms of the sectional anatomy, correlated with the lesional appearances of complete and incomplete ruptures and associated meniscal detachments as shown by clinical testing and arthrotomy findings.

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IRM des points d'angle du genou : bases anatomiques et applications aux genoux traumatiques

Résumé Les points d'angle sont des structures ligamentaires et tendineuses qui renforcent la capsule postéro-médiale et postéro-latérale et participent à la fixation des cornes postérieures des ménisques. Leurs lésions, fréquentes au cours des traumatismes aigus, sont généralement associées à des ruptures des ligaments croisés et des ligaments collatéraux et peuvent être source d'une aggravation de la laxité. Nous rapportons, en corrélation avec l'anatomie en coupe, l'aspect normal de ces structures, et en corrélation avec les données de l'arthrotomie et du testing les aspects lésionnels observés au cours des traumatismes : ruptures complètes, incomplètes et désinsertions méniscales associées.

     

Apoptotic cell death in mouse models of GM2 gangliosidosis and observations on human Tay-Sachs and Sandhoff diseases

Tay-Sachs and Sandhoff diseases are autosomal recessive neurodegenerative diseases resulting from the inability to catabolize GM2 ganglioside by beta-hexosaminidase A (Hex A) due to mutations of the alpha subunit (Tay-Sachs disease) or beta subunit (Sandhoff disease) of Hex A. Hex B (beta beta homodimer) is also defective in Sandhoff disease. We previously developed mouse models of both diseases and showed that Hexa-/- (Tay-Sachs) mice remain asymptomatic to at least 1 year of age while Hexb-/- (Sandhoff) mice succumb to a profound neurodegenerative disease by 4-6 months of age. Here we find that neuron death in Hexb-/- mice is associated with apoptosis occurring throughout the CNS, while Hexa-/- mice were minimally involved at the same age. Studies of autopsy samples of brain and spinal cord from human Tay-Sachs and Sandhoff diseases revealed apoptosis in both instances, in keeping with the severe expression of both diseases. We suggest that neuron death is caused by unscheduled apoptosis, implicating accumulated GM2 ganglioside or a derivative in triggering of the apoptotic cascade.      

Anatomic bases for liver transplantation

Summary This study gathers the anatomic implications for a good liver transplantation. During hepatic removal a left hepatic a.exists in 20% of cases; a right hepatic artery originating from the superior mesenteric a. (SMA) can be the only arterial supply in 9% of cases; the whole lesser omentum has to be removed and the SMA from 6 cm to its origin. The SMA must be freed from the celiac ganglia and its ostium removed with the celiac trunk in an aortic patch cut on the anterior side in order to avoid the renal ostia. During total hepatectomy, dissection of the portal triad is often difficult because of portal hypertension dilating accessory portal veins (parabiliary arcade) and pedicular lymphatics. Nerve plexuses are thick in front of the hepatic artery or behind the portal triad. Transection of triangular ligaments leads to the retrohepatic inferior vena cava (IVC) that must be freed from its posterior tributaries (right suprarenal vein and inferior phrenic veins flowing either into the IVC or into the hepatic veins). One big problem during hepatic replacement is the biliary anastomosis which must be well irrigated. In the recipient, dissection up to the hilum preserves hepatic and pancreatico-duodenal pedicles. The biliary tract of the graft must be cut low, behind the pancreas, and several centimeters of the gastroduodenal artery must be preserved to save hepatic and gastroduodenal pedicles.

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Bases anatomiques de la transplantation hépatique

Résumé Ce travail rassemble les notions anatomiques nécessaires au bon déroulement d'une transplantation hépatique. Le prélèvement du greffon doit enlever tout le petit omentum contenant une éventuelle a. hépatique gauche née de l'a. gastrique gauche (20%) et emporter l'a. mésentérique supérieure jusqu'à 6 cm de son origine pour ne pas oublier une a. hépatique droite née de cette dernière: son ostium est pris avec le tronc clique dans un patch aortique découpé sur la face antérieure. Lors de l'hépatectomie totale, la dissection du pédicule hépatique est rendue délicate par l'hypertension portale qui dilate les veines portes diets accessoires (arcade parabiliaire) et les lymphatiques pédiculaires. Les plexus nerveux sont riches devant l'artère hépatique et derrière le pédicule. La section des ligaments triangulaires droit et gauche amène à la veine cave inférieure (VCI) rétro-hépatique qu'il faut libérer de ses afférences postérieures (en particulier la veine surrénale principale droite toujours haut située et les veines phréniques inférieures qui s'abouchent soit dans la VCI soit dans les veines hépatiques du carrefour). Lors du remplacement, l'anastomose biliaire doit être vascularisée. Chez le receveur la dissection jusqu'au hile permet de conserver les pédicules. La voie biliaire du greffon doit être coupée bas derrière le pancréas et les premiers centimètres de l'artère gastro-duodénale conservés pour préserver les pédicules hépatique et pancréaticoduodénal.

     

Contribution to the study of the tributaries and the termination of the external jugular vein

Summary The dissection of 100 external jugular veins in 50 cadavers was the object of this anatomic study. A certain number of notions concerning the afferent veins, the mode of termination and the valvular system of this vessel were defined. 1)Afferent veins. Along its pathway toward the deep venous system, the external jugular vein successively received: the transverse cervical vein in 88 cases (88%), usually opposite the intersection of the external jugular vein with the dorsal border of the sterno- cleidomastoid muscle; the suprascapular vein in 47 cases (47%); the anterior jugular vein in 46 cases (46%); the cervical vein or anastomosis with the latter in 13 cases (13%). 2)Mode of termination. Forty-three subjects presented a symmetric mechanism. 100 anastomoses can be classed into three types: in 60 cases (60%), the external jugular vein flowed into the jugulo-subclavian venous confluence; in 36 cases (36%), in to the subclavian vein at a distance from its junction with the internal jugular vein; in 4 cases (4%) in to the trunk of the internal jugular vein. 3)Study of the valves. There were studied in 25 subjects (50 external jugular veins). The valves were found in the ostial and paraostial position in 49 out of 50 veins.

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Contribution à l'étude des afférences et de la terminaison de la veine jugulaire externe

Résumé Cette étude anatomique repose sur la dissection de 100 vv. jugulaires externes chez 50 cadavres. Elle a permis de préciser un certain nombre de notions concernant les veines afférentes, le mode de terminaison et le système valvulaire de ce vaisseau. 1)Veines afférentes. Le long de son trajet vers le sytème veineux profond, la v. jugulaire externe reçoit successivement: la v. cervicale transverse dans 88 cas (88 %), habituellement en regard du croisement de la v. jugulaire externe avec le bord dorsal du m. sterno-cléido-mastoïdien ; la v. supra-scapulaire dans 47 cas (47 %); la v. jugulaire antérieure dans 46 cas (46 %) ; la v. céphalique ou une anastomose avec celle-ci dans 13 cas (13 %). 2)Mode de terminaison. Quarante trois sujets présentent un dispositif symétrique. Les 100 abouchements peuvent être classés en trois types : dans 60 cas (60 %) la v. jugulaire externe se déverse dans le confluent veineux jugulo-subclavier ; dans 36 cas (36 %), dans la v. subclavière à distance de sa réunion avec la v. jugulaire interne ; dans 4 cas (4 %) dans le tronc de la v. jugulaire interne. 3)Etude des valvules. Recherchées chez 25 sujets (50 vv. jugulaires externes), les valvules ont été retrouvées dans 49 cas sur 50 en position ostiale ou paraostiale.