Aberrant biliary ducts (vasa aberrantia): Surgical implications

Summary Aberrant biliary ducts (vasa aberrantia) represent a morphological anomaly rather than an anatomical variation of the biliary tree. They have been recognised by anatomists for many years. They are inconstant but fairly frequent and are situated on the surface of the liver in a fibrous envelope or are to be found suspended, in particular in the left triangular ligament. One of them is the sub vesicular duct (ductus subvesicalis), situated in the gallbladder fossa and accounts for more than a third of cases. The vasa aberrantia are in continuity with the intrahepatic bile ducts but they appear to have lost their relationship with the hepatic parenchyma, draining no particular region of the liver. They are not accompanied by arteries and veins which together with the bile ducts normally constitute the portal triad. The vasa aberrantia should be known by surgeons because their existence can sometimes explain the origin of certain cases of biliary peritonitis or on occasions a choleperitonitis following the section of the left hepatic triangular ligament. The frequency of a subvesicular duct is such as to justify routine drainage of the gallbladder bed following cholecystectomy.

---

Les conduits biliaires aberrants (vasa aberrantia): incidences chirurgicales

Résumé Les conduits biliaires aberrants (vasa aberrantia) sont une anomalie morphologique et non une variation de l'arbre biliaire. Ils sont connus des anatomistes depuis longtemps. Ils sont inconstants mais assez fréquents. Ils sont situés à la surface du foie dans son enveloppe fibreuse ou dans son appareil suspenseur, en particulier dans le ligament triangulaire gauche. L'un d'eux est le conduit sous-vésiculaire (ductus subvesicalis), situé dans la fosse de la vésicule biliaire où on le trouve dans plus du tiers des cas. Les vasa aberrantia sont en continuité avec les conduits biliaires intrahépatiques mails ils semblent avoir perdu leurs relations avec le parenchyme hépatique, ne drainant pas de territoire hépatique systématisé. Ils ne sont pas accompagnés par les artères et les veines qui forment normalement avec les conduits beliaires la triade portale. Les vasa aberrantia méritent d'être connus des chirurgiens car leur existence permet d'expliquer l'origine de certaines péritonites biliaires et plus accessoirement celle d'un cholépéritoine consécutif à la section du ligament triangulaire gauche du foie. La fréquence du conduit sous-vésiculaire justifie à elle seule le drainage systématique du lit vésiculaire après cholécystectomie.

     

Expression of alpha-amylase isoenzymes and trypsin by the proliferating epithelium of large intrahepatic bile ducts and intrahepatic peribiliary glands in hepatolithiasis

The expression of alpha-amylase isoenzymes (pancreatic and salivary) and trypsin by the epithelium of large intrahepatic bile ducts and peribiliary glands was examined immunohistochemically in hepatolithiasis ( n = 22), extrahepatic biliary obstruction ( n = 20) and normal liver ( n = 22). Hepatolithiasis was associated with marked proliferation of bile duct cells and peribiliary glands. Expression of pancreatic and salivary amylase was observed in the proliferating bile duct cells and peribiliary glands of all livers, and trypsin was found in 68% of the livers. In extrahepatic biliary obstruction, proliferation of the biliary epithelium was less marked, but expression of amylase isoenzymes was observed in all livers and trypsin was found in 50%. All normal livers showed expression of amylase isoenzymes in large intrahepatic bile ducts, septal bile ducts and peribiliary glands, and trypsin was found in 73%. The density of enzyme-containing acini was highest in hepatolithiasis, intermediate in extrahepatic biliary obstruction and lowest in normal liver. These results show that the proliferating biliary epithelium in hepatolithiasis contains amylase isoenzymes and trypsin and that biliary epithelium retains the ability to produce these enzymes after proliferation, suggesting that a large amount of amylase isoenzymes and trypsin may be secreted into the bile ducts in hepatolithiasis. These enzymes may play an important role in the pathophysiology of hepatolithiasis.     

Parenchyma-wise technique for the harvest and implantation of hepatic segment 2-3 grafts: Anatomic basis and surgical steps

We propose a technique for pediatric liver transplantation that does not waste the donor's parenchyma. Organ shortage has extended criteria for donor acceptance, such that even individuals with livers of suboptimal volume can donate their segment 2-3. By incorporating wise use of parenchyma, our proposed technique for harvesting segment 2-3 for implantation in a pediatric recipient benefits these and other donors, and it might increase donations. This is especially important in countries in which procurement of organs from the deceased is not allowed. Our technique also aims to solve the problem of the large-for-size syndrome for neonates and extremely small infants and to allow for primary closure of the abdomen. This technique enables harvest of the following four grafts: (1) complete segment 2-3; (2) reduced segment 2-3; (3) complete segment 3; and (4) reduced segment 3. The surgeon will select the type that has suitable graft-to-recipient weight ratio and that suits the donor's liver anatomy and volume. These four types benefit the donor by preserving the parenchyma of segment 4 and the left part of the caudate lobe. The three graft types other than the complete segment 2-3 graft will also preserve varying fractions of the parenchyma of segment 2-3. The technique for complete segment 2-3 graft can be put into practice immediately; the techniques for the other three grafts need an imaging modality to preoperatively delineate the donor's fourth-order bile ducts. We expect to correct this deficiency in the near future by developing the requisite imaging technique.     

Dynamic anatomy of the acetabulum: an experimental approach and surgical implications

Summary The deformations and stresses acting on the acetabular rim have not been very precisely documented. The authors present a study based on an experimental simulation of hip loading with anatomic correlations. 122 dissections were performed in order to define the anatomic aspect of the roof (and especially of Byers's area 17) and the intermediate area between the anterior and posterior acetabular cornua. Ten fresh cadavers were tested on the lines of previous studies on monopodal or bipodal loading. An extensometric study was performed with special attention to the transverse acetabular ligament, supra-acetabular area and obturator foramen. The area 17 of Byers is a transitional zone and the mobility of the posterior cornu is 3 times that of the anterior cornu. Resection of the acetabular ligament modifies the displacement of the posterior cornu under loading but has no influence on deformation of the oburator foramen. The biomechanical behavior of the acetabular roof in the standing position is influenced by the conditions of monopodal or bipodal loading and by femoral rotation, but a tendency to extrusion was constantly noted.

---

L'anatomie dynamique de l'acétabulum: bases expérimentales et réflexions sur les applications chirurgicales

Résumé Les déformations et les contraintes en périphérie de l'acétabulum ont été peu étudiées. Les auteurs présentent un travail de corrélation entre les constatations anatomiques et la simulation expérimentale de mise en charge. 122 dissections ont été réalisées pour préciser l'aspect anatomique du toit et en particulier la zone 17 de Byers, les régions intermédiaires avec les cornes antérieures et postérieures. 10 hanches de cadavres frais ont été étudiées selon les conditions classiques de mise en charge mono et bipodale. Une étude extensométrique a été pratiquée en tenant compte tout spécialement du ligament transverse, de la région supra-acétabulaire et du foramen obturé. La zone 17 de Byers est une zone transitionnelle et la mobilité de la corne postérieure est trois fois plus importante que celle de la corne antérieure. La section du ligament transverse de l'acétabulum modifie le déplacement de la corne postérieure au cours des mises en charge mais n'a pas d'influence significative sur la déformation du foramen obturé. Le comportement biomécanique du toit de l'acétabulum en position debout est influencé par les conditions d'appui mono ou bipodal, les rotations fémorales, mais une tendance constante à l'extrusion a été notée.

     

Variation in Kaplan fiber insertion to the distal femur and surgical implications: A cadaveric anatomical study comparing Asian and Caucasian knees

BackgroundThe iliotibial band together with its attachment to the distal femur, known eponymously as the Kaplan fibers, has been shown to contribute to anterolateral rotatory stability of the knee. However, there remains paucity of data regarding the detailed anatomy of the Kaplan fibers to aid us in anatomical-based surgical reconstruction of these structures. The aim of our study was to identify and compare the presence and quantitative anatomy of the Kaplan fibers in Caucasian and Asian cadavers.MethodsTwenty paired fresh-frozen Asian and 20 unpaired embalmed Caucasian cadaveric knees were dissected using a standard outside–in technique. The presence, qualitative and quantitative measurements of any distal femoral attachments of the iliotibial band were recorded. Mean values of its dimensions were calculated and compared between the Caucasian and Asian groups.ResultsA consistent supracondylar attachment of the iliotibial band was found in all Caucasian knees and in 19 of 20 Asian knees. The fibers were noted to have two variations with regard to their insertion to the distal femur, either as a single limb or as a double limb attachment, averaging between 30 mm and 40 mm from the lateral femoral epicondyle. No statistically significant difference was noted in dimensions of the fibers between the Caucasian and Asian groups.ConclusionsThe Kaplan fibers are a consistent attachment of the iliotibial band at the distal femur in both Caucasian and Asian knees with two different patterns of insertion. Surgical reconstructions should aim to recreate these attachments to be as anatomically based as possible.     

Characterization of the oropharynx: anatomy,histology, immunology,squamous cell carcinoma and surgical resection

Understanding the structure and function of the oropharynx is paramount for providing excellent patient care. In clinical oncology, the oropharynx is generally divided into four distinct components: (i) the base of the tongue; (ii) the soft palate; (iii) the palatine tonsillar fossa; and (iv) the pharyngeal wall. The oropharyngeal mucosa is distinct from other mucosal surfaces in the body, as it is composed of a reticulated epithelium with a discontinuous basement membrane, also known as lymphoepithelium. This review describes the anatomy, histology, immunology and surgical resection of the oropharynx as they relate to oncological care.     

Stereophotogrammetric surface anatomy of the anterior cruciate ligament's tibial footprint: Precise osseous structure and distances to arthroscopically-relevant landmarks

Background

While femoral tunnel malposition is widely recognized as the main technical error of failed anterior cruciate ligament (ACL) surgery, tibial tunnel malposition is likely underrecognized and underappreciated.

Gross anatomy in the surgical curriculum in Switzerland: Improved cadaver preservation,anatomical models,and course development

The invention of new techniques for surgery and interventional radiology demand improved training for ongoing specialists. The Anatomical Institutes in Switzerland support these requirements by establishing hands‐on practical training courses by using new procedures for cadaver embalming and model construction. Improvements allow courses to provide students with more realistic simulations of both established and experimental surgical methods. Through these changes, the value of in‐depth gross anatomy is enhanced as a topic of fundamental importance for the postgraduate medical and surgical curriculum. The web site http://www.unifr.ch/sgahe/snga.html contains information on courses using the Thiel embalming solution. Details about training courses in Switzerland using anatomical models are available at http://www.heartlab.org , http://www.vascular‐international.org , and http://www.elastrat.com . Anat Rec (New Anat) 265:254–256, 2001. © 2001 Wiley‐Liss, Inc.     

Superior approach to the inferior laryngeal nerve in thyroid surgery: anatomy, surgical technique and indications

Goals of the study To describe the anatomical bases of the surgical access to the higher part of the thyroid lobe, with first location of the inferior laryngeal nerve at its laryngeal penetration, to discuss the advantages and disadvantages of this surgical technique and to determine the operational indications.Population and method A prospective study of surgical anatomy performed over a period of 18 months was conducted. A total of 25 (22 women and 3 men) patients with cervicothoracic goitre underwent total thyroidectomy. Thyroid lobectomies were performed using the technique of “capsular thyroidectomy”, with first location and complete dissection of the inferior laryngeal nerve. A neurostimulator was systematically used for the location of the inferior laryngeal nerve and also the external laryngeal nerve.Results The first detection of the inferior laryngeal nerve at the top of the thyroid lobe was positive in 49/50 cases. A superior parathyroid gland was found in 75% of cases and an inferior parathyroid gland in 37.5% of cases. The external laryngeal nerve was stimulated and respected in 12,5% of cases. No voice trouble, no laryngeal palsy and no definitive hypoparathyroidism occurred after surgery.Conclusion Safeguarding of the inferior laryngeal nerve is the principal and obligatory stake in thyroid surgery. Locating the inferior laryngeal nerve at the level of its laryngeal penetration at the superior pole of the thyroid region is necessary in cases of particular situations: huge cervicothoracic goitres, re-operative procedures and various anatomical variations. The use of a neurostimulator secures this technique.     

Anatomo‐radiological patterns of pancreatic vascularization,with surgical implications: Clinical and anatomical study

The pancreas receives multiple arterial sources that should be considered in patients undergoing pancreatic surgery. The aim of this study is to describe pancreatic vascularization and to explore the anatomical basis of postoperative complications. Ten specimens from unembalmed cadavers, including the retroperitoneal vessels and organs and spleen, were injected with acrylic resins to obtain vascular casts. Thirty computed tomography angiographies (CTA) of subjects with no pancreatic pathology (mean age 70.9 years) were also analyzed. A paucivascular area at the neck of the pancreas was apparent in all vascular casts. At CTA: (1) the transverse pancreatic artery, the only artery running from the cervicocephalic to the somatocaudal segment, was visible in 76.9% of cases; (2) the splenic artery was suprapancreatic in 66.7% and intrapancreatic with a tortuous course in 33.3%; (3) the posterior superior pancreaticoduodenal artery was visible in 100% of cases, the anterior superior pancreatico‐duodenal artery in 92.6%, the anterior inferior pancreaticoduodenal artery in 73.1%, the posterior inferior pancreaticoduodenal artery in 86.4%, the dorsal pancreatic artery in 65.4%, the great pancreatic artery in 73.1%, and the pancreatic arteries to the body and caudal pancreatic arteries in 96.2%. Our study demonstrated great individual variability of the pancreatic vasculature, which can be explored by CTA and could be relevant to surgical procedures. Clin. Anat. 30:614–624, 2017. © 2017 Wiley Periodicals, Inc.     

Morphology of the bile ducts of the brook lamprey,Lampetra lamottenii (Le Sueur) before and during infection with the nematode,Truttaedacnitis stelmioides (Vessichelli, 1910) (Nematoda: Cucullanidae)

Routine light microscopy and transmission and scanning electron microscopy were used to describe and compare the biliary tree of larval Lampetra lamottenii before and during infestation of the bile ducts with the nematode, Truttaedacnitis stelmioides. The most prominent changes to the biliary tree following infection by the parasite are the dilation of the bile ducts, alterations to their epithelial cells, and an increase in periductal fibrous tissue. In recently infected animals, the simple epithelium of dilated bile ducts often contains many mitotic figures. In long-term infestations, the epithelium is stratified or pseudostratified. Changes to the fine structure of the biliary epithelial cells include increase and/or dilation of the RER and SER, and increases in microfilaments, intermediate filaments, and microtubules. The abundance of dense bodies may reflect enhance reabsorption of biliary constituents, and their accumulation may ultimately result in cytolysis. There are increased mucous granules in the apical cytoplasm of biliary epithelial cells and an abundance of mucinous material within the bile duct lumen, and the basal lamina appears thickened. The changes to the liver of L. lamottenii following infection are discussed and compared to those reported in small mammals following bileduct ligation, in patients with extrahepatic biliary obstruction, and in parasitic infection of the biliary tree.© Willey-Liss, Inc.     

Gross anatomy,histological, and histochemical analysis of the eyelids and orbital glands of the neonate pygmy hippopotamus (Suina: Choeropsis liberiensis or Hexaprotodon liberiensis,Morton 1849) with reference to its habitat

The pygmy hippopotamus is phylogenetically related to members of both the Suidae and Cetacea. However, differences in their habitats may have resulted in variation in the anatomy and physiology of the ocular adnexa between these species. Therefore, this study focuses on the identification of accessory organs of the eye, which are typical for the pygmy hippopotamus and are comparable to organs present in mammals related to it. Moreover, the secretions produced by the superficial gland of the third eyelid, the deep gland of the third eyelid and the lacrimal gland were examined, as they ensure eyeball protection. In the upper and lower eyelids, numerous serous glands where identified, which were typical for the pygmy hippopotamus and similar as in the Cetacea. This study enabled to identify additional folds in the eyelids of the pygmy hippopotamus. Lymphoid follicles and diffuse lymphocytes were not found in the lymphoid region in the upper or lower eyelids and the third eyelid, which was most likely caused by the age of the studied hippopotamuses. An accurate histochemical analysis revealed that the secretions of the pygmy hippopotamus are very similar to the Sus scrofa. The structural differences between the pygmy hippopotamus and representatives of Cetacea are most likely caused by the fact that most of Cetacea live in saltwater and are exposed to more frequent fluctuations in water temperature compared to the pygmy hippopotamus, which lives in fresh water and does not lead a migratory lifestyle like the Cetacea.