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.

Aberrant bile ducts, 'remnant surface bile ducts,' and peribiliary glands: descriptive anatomy, historical nomenclature, and surgical implications.

The term "aberrant bile ducts" has been used to designate three heterogeneous groups of biliary structures: (1) bile ducts degenerating or disappearing (unknown etiology, diverse locations); (2) curious biliary structures in the transverse fissure; and (3) aberrant right bile ducts draining directly into the common hepatic duct. We report our observations on these three groups. Twenty-nine fresh human livers of stillborns and adults were injected differentially with colored latex and dissected. Adult livers showed portal venous and hepatic arterial branches, and bile ducts not associated with parenchyma, subjacent to and firmly adherent with the liver capsule: elements of ramifications of normal sheaths were present on the liver's surface. These ramifications, having lost parenchyma associated with them, then sequentially lost their portal branches, bile ducts and arterial branches. This process affected the ramifications of the sheaths in the left triangular ligament, adjacent to the inferior vena cava, in the gallbladder bed and anywhere else on the liver's surface and resulted in the presence of bile ducts accompanied by portal venous and/or hepatic arterial branches and not associated with parenchyma for a period of time. This first group represented normal bile ducts that do not meet the criteria of aberration and could be appropriately designated "remnant surface bile ducts." Such changes were not found in the transverse fissures and review of the literature revealed that the curious biliary structures are the microscopic peribiliary glands. The third group met the criteria of aberration and the anatomy of a representative duct is described.

Perineal hernia: surgical anatomy, embryology, and technique of repair.

Perineal hernia is the protrusion into the perineum of intraperitoneal or extraperitoneal contents through a congenital or acquired defect of the pelvic diaphragm. The first case was reported by de Garangeot in 1743. Perineal hernias may occur anteriorly or posteriorly to the superficial transverse perineal muscles. Congenital perineal hernia is a rare entity. Failure of regression of the peritoneal cul de sac of the embryo is considered a predisposing factor for hernia formation. Acquired perineal hernias are primary or secondary. Primarily acquired perineal hernias are caused by factors associated with increased intra-abdominal pressure. They are more common in females as a result of the broader female pelvis and the attenuation of the pelvic floor during pregnancy and childbirth. Secondarily acquired perineal hernias are incisional hernias associated with extensive pelvic operations such as abdominoperineal resection of the anorectum and pelvic exenteration. Pain in the perineal area, intestinal obstruction, topical skin erosion, and difficulty with urination necessitate the surgical repair of a perineal hernia. This can be accomplished through transabdominal, perineal, or combined abdominoperineal approaches. The defect in the muscles of the pelvic diaphragm may be closed either with direct suturing or by using autogenous tissues or synthetic mesh.

Surgical anatomy of the retroperitoneal spaces, Part V: Surgical applications and complications.

Knowledge of the surgical anatomy of the retroperitoneum is crucial for surgery of the retroperitoneal organs. Surgery is essential for treatment of retroperitoneal pathologies. The list of these diseases is extensive and comprises acute and chronic inflammatory processes (abscess, injury, hematoma, idiopathic fibrosis), metastatic neoplasms, and primary neoplasms from fibroadipose tissue, connective tissue, smooth and striated muscle, vascular tissue, somatic and sympathetic nervous tissue, extraadrenal chromaffin tissue, and lymphatic tissue. The retroperitoneum can be approached and explored by several routes, including the transperitoneal route and the extraperitoneal route. The retroperitoneal approach to the iliac fossa is used for ectopic renal transplantation. Safe and reliable primary retroperitoneal access can be performed for laparoscopic exploration. The anatomic complications of retroperitoneal surgery are the complications of the organs located in several compartments of the retroperitoneal space. Complications may arise from incisions to the somatic wall, somatic nerves, blood and lymphatic vessels, lymph nodes, visceral autonomous plexuses, and neighboring splanchna.

Surgical anatomy of the retroperitoneal spaces, Part IV: retroperitoneal nerves.

We present surgicoanatomical topographic relations of nerves and plexuses in the retroperitoneal space: 1) six named parietal nerves, branches of the lumbar plexus: iliohypogastric, ilioinguinal, genitofemoral, lateral femoral cutaneous, obturator, femoral. 2) The sacral plexus is formed by the lumbosacral trunk, ventral rami of S1-S3, and part of S4; the remainder of S4 joining the coccygeal plexus. From this plexus originate the superior gluteal nerve, which passes backward through the greater sciatic foramen above the piriformis muscle; the inferior gluteal nerve also courses through the greater sciatic foramen, but below the piriformis; 3) sympathetic trunks: right and left lumbar sympathetic trunks, which comprise four interconnected ganglia, and the pelvic chains; 4) greater, lesser, and least thoracic splanchnic nerves (sympathetic), which pass the diaphragm and join celiac ganglia; 5) four lumbar splanchnic nerves (sympathetic), which arise from lumbar sympathetic ganglia; 6) pelvic splanchnic nerves (nervi erigentes), providing parasympathetic innervation to the descending colon and pelvic splanchna; and 7) autonomic (prevertebral) plexuses, formed by the vagus nerves, splanchnic nerves, and ganglia (celiac, superior mesenteric, aorticorenal). They include sympathetic, parasympathetic, and sensory (mainly pain) fibers. The autonomic plexuses comprise named parts: aortic, superior mesenteric, inferior mesenteric, superior hypogastric, and inferior hypogastric (hypogastric nerves).

Surgical anatomy of the retroperitoneal spaces, Part III: Retroperitoneal blood vessels and lymphatics.

In this article, we discuss the surgical anatomy of the blood vessels and the lymphatic vessels and lymph nodes found in the retroperitoneum. Retroperitoneal blood vessels include the aorta and all its branches--parietal and visceral--from the diaphragm to the pelvis, and the inferior vena cava and its tributaries. The retroperitoneal lymphatics form a very rich and extensive chain. As a general rule, lymphatics follow the arteries and named lymph nodes are found at the root of the arteries. Retroperitoneal nodes of the abdomen comprise the inferior diaphragmatic nodes and the lumbar nodes. The latter are classified as left lumbar (aortic), intermediate (interaorticovenous), and right lumbar (caval). These nodes surround the aorta and the inferior vena cava. Around the aorta lie the paraortic nodes, preaortic nodes (include celiac, superior mesenteric, inferior mesenteric nodes collecting lymph from the splanchna supplied by the homonymous arteries), and retroaortic nodes. Similarly, around the vena cava lie the paracaval, precaval, and retrocaval nodes. Pelvic nodes include the common iliac, external and internal iliac, obturator, and sacral nodes.

Surgical anatomy of the retroperitoneal spaces part II: the architecture of the retroperitoneal space.

The extraperitoneal space extends between peritoneum and investing fascia of muscles of anterior, lateral and posterior abdominal and pelvic walls, and circumferentially surrounds the abdominal cavity. The retroperitoneum, which is confined to the posterior and lateral abdominal and pelvic wall, may be divided into three surgicoanatomic zones: centromedial, lateral (right and left), and pelvic. The preperitoneal space is confined to the anterior abdominal wall and the subperitoneal extraperitoneal space to the pelvis. In the extraperitoneal tissue, condensation fascias delineate peri- and parasplanchnic spaces. The former are between organs and condensation fasciae, the latter between this fascia and investing fascia of neighboring muscles of the wall. Thus, perirenal space is encircled by renal fascia, and pararenal is exterior to renal fascia. Similarly for the urinary bladder, paravesical space is between the umbilical prevesical fascia and fascia of the pelvic wall muscles-the prevesical space is its anterior part, between transversalis and umbilical prevesical fascia. For the rectum, the "mesorectum" describes the extraperitoneal tissue bound by the mesorectal condensation fascia, and the pararectal space is between the latter and the muscles of the pelvic wall. Perisplanchnic spaces are closed, except for neurovascular pedicles. Prevesical and pararectal (presacral) and posterior pararenal spaces are in the same anatomical level and communicate. Anterior to the anterior layer of the renal fascia, the anterior interfascial plane (superimposed and fused mesenteries of pancreas, duodenum, and colon) permits communication across the midline. Thus parasplanchnic extraperitoneal spaces of abdomen and pelvis communicate with each other and across the midline.

Surgical anatomy of the retroperitoneal spaces--part I: embryogenesis and anatomy.

Embryologically, the retroperitoneal (extraperitoneal) connective tissue includes three strata, which respectively form the internal fascia lining of the body wall, the renal fascia, and the covering of the gastrointestinal viscera. All organs, vessels, and nerves, that lie on the posterior abdominal wall, along with their tissues and surrounding connective and fascial planes, are collectively referred to as the retroperitoneum. The retroperitoneal space is the area of the posterior abdominal wall that is located between the parietal peritoneum and the fascia. Within the greater retroperitoneal space, there are also several small spaces, or subcompartments. Loose connective tissue and fat surround the anatomic entities, and, to a variable degree, occupy the subcompartments. The multilaminar thoracolumbar (lumbodorsal) fascia begins at the occipital area and terminates at the sacrum.

Protective mechanisms of the common fibular nerve in and around the fibular tunnel: a new concept.

The most frequent site at which the common fibular nerve is affected by compression, trauma, traction, masses, and surgery is within and around the fibular tunnel. The aim of this study was to determine whether there were protective mechanisms at this site that guard against compression of the nerve. Twenty-six lower limbs of 13 preserved adult cadavers (11 males and two females) were used. Proximal to the entrance of the tunnel, three anatomical configurations seemed to afford the required protection for the nerve: reinforcement of the deep fascia; tethering of the common fibular nerve to both the tendon of the biceps femoris and the reinforced fascia; and the particular arrangement of the deep fascia, fibular head, and soleus and gastrocnemius muscles. At the entrance of the tunnel, contraction of the first segment of fibularis longus muscle could afford the required protection. In the tunnel, contraction of the second and third segments of fibularis longus muscle could guard against compression of the nerve. The tough fascia on the surface of fibularis longus muscle and the fascial band within it, which have long been accused of compression of the nerve, may actually be elements of the protective mechanisms. We conclude that there are innate, anatomical protective mechanisms which should be taken into consideration when decompressing the common fibular nerve. To preserve these mechanisms whenever possible, the technique should be planned and varied according to the underlying etiology.

Lumbar hernia: surgical anatomy, embryology, and technique of repair.

Lumbar hernia is the protrusion of intraperitoneal or extraperitoneal contents through a defect of the posterolateral abdominal wall. Barbette was the first, in 1672, to suggest the existence of lumbar hernias. The first case was reported by Garangeot in 1731. Petit and Grynfeltt delineated the boundaries of the inferior and superior lumbar triangles in 1783 and 1866, respectively. These two anatomical sites account for about 95 per cent of lumbar hernias. Approximately 20 per cent of lumbar hernias are congenital. The rest are either primarily or secondarily acquired. The most common cause of primarily acquired lumbar hernias is increased intra-abdominal pressure. Secondarily acquired lumbar hernias are associated with prior surgical incisions, trauma, and abscess formation. During embryologic development, weakening of the area of the aponeuroses of the layered abdominal muscles that derive from somitic mesoderm, which invades the somatopleure, may potentially lead to lumbar hernias. Repair of lumbar hernias should be performed as early as possible to avoid incarceration and strangulation. The classic repair technique uses the open approach, where closure of the defect is performed either directly or using prosthetic mesh. The laparoscopic approach, either transabdominal or extraperitoneal, is an alternative.

One snake or two: the symbols of medicine.

In antiquity, Asklepios was portrayed with a stout staff around which was coiled a snake. Hermes (Mercury), the messenger of the gods, was portrayed with a wand, often with wings, around which were coiled two snakes. During the Renaissance and up to modern times, in varied locales, each icon has been termed the caduceus and afforded the status of the symbol of medicine. It is proposed that this confusion did not arise from ignorance, but from the loss of the deeper significance of the symbols, and from the replacement of religious iconographic constraints by aesthetic and decorative considerations.

Reflections on dissection: leave no student behind.

Dissection is being reduced--and even removed--from the medical curriculum in Australia, New Zealand, the United Kingdom, Ireland, and the United States. Dissection's contribution to the curriculum is too important to be diminished. To understand the human body, students must dissect. To avoid anatomical complications, future surgeons need the knowledge they can gain from dissection. Cadavers reveal the uniqueness of each body and the body's strength and fragility, which cannot be learned from books or computers. Cadavers offer surgical skill-building opportunities and confrontation with death. For all its strengths, however, dissection alone does not teach everything the student needs to know. Other educational tools (books, CT and MRI, animation of developmental processes) successfully fill in gaps of knowledge. Surgeons and educators must recognize the threat that decreased dissection poses to our students and patients. They must take steps to support dissection in the medical curriculum or, if it has disappeared, to bring it back.

Anatomy of the lymphatics.

The lymphatic system is perhaps the most complicated system of Homo sapiens. An introduction to the anatomy, embryology, and anomalies of the lymphatics is presented. The overall anatomy and drainage of the lymphatic vessels in outlined. The topographic anatomy, relations, and variations of the principle vessels of the lymphatic system (the right lymphatic duct, the thoracic duct, and the cisterna chyli) are presented in detail.

Groin hernia: anatomical and surgical history.

The history of surgical repair of groin hernia is a lengthy record of assorted techniques in search of a cure for an ailment that comes in many sizes and shapes and that has plagued humanity for thousands of years. Although improvements are still being sought and found, for several decades surgeons have had the means to relieve most hernia sufferers. A remaining issue is whether the wide array of surgical procedures can or should be whittled down to a few "standard" operations that are safe, effective, and cost-efficient. The history of the anatomy of groin hernia shows how much there was to learn and how much remains to be learned. It also shows how important it is for the surgeon to know and understand both the anatomy of the area and the formation of groin hernia.

"To afford the wounded speedy assistance": Dominique Jean Larrey and Napoleon.

Dominique Jean Larrey (1766-1842) has been described as the father of modern military surgery and is considered even today as the model military surgeon. He developed a plan of rapid evacuation of wounded soldiers from the battlefield during combat, using flexible medical units which he named ambulances volantes ("flying ambulances"). He won the admiration of Napoleon Bonaparte (1769-1821), who was amazed by the results of Larrey's sanitary system. Larrey spent almost 18 years with Napoleon, accompanying him in 25 campaigns, 60 battles, and more than 400 engagements. Napoleon's enormous military success was due not only to his strategy and skill but also to the medical services provided by Larrey. The surgeon became a master of wound management and limb amputation. In his vivid battlefield journals, Larrey documented the course of tetanus, the pathophysiology of cold injury, the effective control of hemorrhage, the drainage of empyema and hemothorax, the aspiration of pericardial effusion or hemopericardium, and the packing of sucking chest wounds. Larrey established a categorical rule for the triage of war casualties, treating the wounded according to the observed gravity of their injuries and the urgency for medical care, regardless of their rank or nationality.

The monarch and the master: Peter the Great and Frederik Ruysch.

The extraordinary European journey of Tsar Peter the Great and his passage to Amsterdam, The Netherlands, allowed him to meet a great figure of medical history who offered insight into the mysteries surrounding the structure of the human body. The famous Dutch anatomist Frederik Ruysch, preeminent in dissection and anatomical preservation, impressed the emperor and inspired his love for anatomy and surgery. Peter the Great was fascinated by the study of the structure of the human body and spent many hours in the anatomical cabinet of Ruysch. This impressive collection of cadavers and anatomical specimens, described as "a perfect necropolis," was both a laboratory for teaching anatomy and a bizarre and unique form of art. The profound and enduring impression that the West made on the emperor also led him to modernize the medical services in his homeland, Russia.

Richter hernia: surgical anatomy and technique of repair.

Richter hernia (partial enterocele) is the protrusion and/or strangulation of only part of the circumference of the intestine's antimesenteric border through a rigid small defect of the abdominal wall. The first case was reported in 1606 by Fabricius Hildanus. The first definition of partial enterocele was given by August Gottlieb Richter in 1785. Sir Frederick Treves discriminated it from Littre hernia (hernia of the Meckel diverticulum). More often these hernias are diagnosed in the sixth and seventh decades of life. They comprise 10 per cent of strangulated hernias. Their common sites are the femoral ring, inguinal ring, and at incisional trauma. The most-often entrapped part of the bowel is the distal ileum, but any part of the intestinal tube may be incarcerated. These hernias progress more rapidly to gangrene than other strangulated hernias, and obstruction is less frequent. The gold standard technique for repair is the preperitoneal approach, followed by laparotomy and resection if perforation is suspected.