Wei Chen, PhD

• Associate Professor in Medicine
• Member of the Duke Cancer Institute

https://medicine.duke.edu/faculty/wei-chen-phd

The middle lamella separates these erector spinae muscles from quadratus lumborum erectile dysfunction caused by hydrocodone buy cheap sildalist 120mg on line. Extending medially erectile dysfunction melanoma sildalist 120 mg purchase otc, the anterior lamella attaches to the vertebral transverse process and is continuous with the fascia that invests the psoas muscle erectile dysfunction caused by anabolic steroids order sildalist paypal. Historically erectile dysfunction doctor orlando discount sildalist 120 mg buy, the retroperitoneum Transversus abdominis muscle Quadratus lumborum muscle Psoas major muscle Erector spinae muscles Latissimus dorsi muscle Thoracolumbar fascia Anterior layer Middle layer Posterior layer has been divided embryologically based on these three strata (Tobin erectile dysfunction medication samples 120 mg sildalist purchase mastercard, 1944). The outer stratum covers the epimysium of the abdominal wall muscles and becomes the transversalis fascia. The intermediate stratum is associated with the genitourinary organs, and the inner stratum is associated with the gastrointestinal organs (MacLennan, 2012). The aim is not to have the reader memorize what each embryologic stratum becomes during development. Rather, these embryologic strata categorize the retroperitoneal fasciae, which compartmentalize various spaces within the retroperitoneum. Transversalis Fascia and Posterior Pararenal Space the outer stratum forms the transversalis fascia, which lies deep to the transversus abdominis muscle and superficial to the preperitoneal fat and peritoneum. Anterior layer lumbodorsal fascia Middle layer lumbodorsal fascia Sacrospinalis Posterior layer lumbodorsal fascia Drawing aside m. Transverse section through the kidney and posterior abdominal wall showing the lumbodorsal fascia incised. Through such a lumbodorsal incision, the kidney can be reached without incising muscle. It may fuse medially with the posterior lamina of Gerota fascia, which is of clinical significance during retroperitoneal dissection because this fascia must be incised to allow access to the renal hilum. The anterior boundary is formed by the posterior lamina of Gerota fascia, and the posterior and lateral boundaries are formed by the transversalis fascia (Tobin, 1944). Gerota Fascia (Renal Fascia) and Perirenal Space the anterior lamina (fascia of Toldt or prerenal fascia) and the posterior lamina (fascia of Zuckerkandl or retrorenal fascia) of the renal fascia are derived from the intermediate stratum, which embeds the genitourinary organs. The two laminae together form the renal fascia, eponymously named Gerota fascia, after the Romanian anatomist Dimitrie D. The perirenal space contains the adrenal, kidney, ureter, perirenal fat, renal vascular pedicle, and gonadal vessels. The perirenal fat is finer and lighter yellow than the coarser yellow-orange pararenal fat. This color distinction can be helpful during colon mobilization for retroperitoneal surgery. The anatomy of the adrenal, kidney, and ureter is discussed in detail in their respective chapters. The posterior lamina of Gerota fascia is thicker and more frequently visualized radiographically than the anterior lamina. These two layers merge laterally to form the lateroconal fascia, which separates the anterior and posterior pararenal spaces and continues anterolaterally deep to the transversalis fascia. There is some controversy regarding the medial and inferior extents of the perirenal space. Historically, it was assumed that there was no communication between the right and left perirenal spaces. However, based on in vivo cases and cadaveric injection studies, there may be some communication across the midline below the level of the renal hilum (Lim et al. Anterior view of Gerota fascia on the right side, split over the right kidney (which it contains) and showing inferior extension enveloping the ureter and gonadal vessels. The tail of the pancreas is closely associated with the spleen and must be accounted for during left retroperitoneal surgery because of its proximity to the upper pole of the left kidney and left adrenal. The duodenum is 20 cm to 25 cm in length and can be divided into four distinct parts. The first (superior) portion is intraperitoneal and extends from the pylorus to the neck of the gallbladder. The second (descending) and third (horizontal or inferior) portions of the duodenum are contained within the retroperitoneum. The second, descending portion of the duodenum is critical to the urologist because of its proximity to the right renal hilum. The duodenum may be mobilized medially using a Kocher maneuver to expose these right-sided retroperitoneal structures. During left-sided retroperitoneal surgery, as the colon is reflected medially the mesentery thins and the duodenum can be encountered. The common bile duct and the main pancreatic duct combine to enter the second portion of the duodenum at the ampulla of Vater (hepatopancreatic ampulla). The fourth and final portion ascends and becomes intraperitoneal as it transitions into the jejunum. As with the duodenum, portions of the colon are secondarily retroperitoneal because they developed intraperitoneally but fused with the posterior abdominal wall during embryogenesis. The ascending colon and hepatic flexure overlie the right-sided retroperitoneal structures, and the splenic flexure and descending colon cover the left-sided retroperitoneal structures. To gain access to the kidneys transperitoneally, the ipsilateral colon must be reflected medially in most instances. This can be performed by mobilizing the colon at the white line of Toldt, which visually represents the transition from the colonic visceral peritoneum to the posterior parietal peritoneum. Care must be taken to divide the hepatocolic and splenocolic ligaments sharply when necessary to avoid iatrogenic injury to the liver and spleen, which is often due to excessive retraction during attempts to obtain adequate exposure. Recent investigations have begun to classify the mesentery as a distinct organ that has intestinal, vascular, immunologic, and endocrine function. Initial early depictions of the mesentery by Leonardo Da Vinci showed a continuous structure from the small bowel to the colon. Posterior view of Gerota fascia on the right side, rotated medially with the contained kidney, ureter, and gonadal vessels, exposing the muscular posterior body wall covered by the transversalis fascia. Previously, it was suggested that the perirenal space is closed inferiorly by the fusion of Gerota fascia. However, in vivo cases and cadaveric injection studies demonstrated that the perirenal space has a conelike shape that is open at its inferior extent in the extraperitoneal pelvis (Lim et al. These boundaries are of clinical significance in the pathology of urologic disease because they function to contain perinephric fluid collections, which include urine (traumatic or iatrogenic urinary extravasation, obstructive uropathy with calyceal rupture), blood (traumatic or iatrogenic perinephric hematoma, ruptured aneurysm), or purulence (perinephric abscess or infected urinoma). Clinically, this space is significant because it can be developed to gain access to the kidney anteriorly when followed medially from the white line of Toldt. During this event, the white line of Toldt is formed at the lateral border of the fusion of the colonic mesentery with the posterior peritoneum. The anterior pararenal space contains the secondarily retroperitoneal organs: the ascending and descending colon, pancreas, and second and third portions of the duodenum. These organs are intraperitoneal at one point during embryogenesis; however, they become retroperitoneal secondarily as they attach to the posterior abdominal wall when the inner stratum fuses with the primary dorsal peritoneum. Chapter 75 Surgical, Radiographic, and Endoscopic Anatomy of the Retroperitoneum 1668. It acts as a scaffolding for the small and large intestines, suspending these structures from the posterior abdominal wall. As the mesentery is the first barrier between the intestines and the body, it also acts as a sampling reservoir for systemic immune responses. Mesenteric nodes regulate the cell-mediated immune response with the adjacent intestinal mucosa. Several mesenteric disease processes are of important clinical significance to the practicing urologist. Internal herniation resulting from surgically created mesenteric defects can cause a potentially life-threatening postoperative complication. After bowel segment isolation, it is imperative that small defects in the mesentery are closed primarily because the risk of herniation is higher in these cases. The intima consists of a layer of endothelial cells surrounded by subendothelial connective tissue. The media layer contains vascular smooth muscle cells and elastic connective tissue that control the caliber of the vessel. It contains the nerves that control vasomotor tone and the vasa vasorum (Latin, "vessels of the vessels"), which are smaller vessels that supply the walls of larger vessels. The superior adrenal artery branches from the inferior phrenic artery and supplies the ipsilateral adrenal gland. The superior arterial blood supply to the adrenal is constant; however, the middle and inferior arteries to the adrenal are variable. These arteries vary in number and location with the most common variant being the middle adrenal artery arising from the aorta and the inferior adrenal arising from the renal artery. The next branch of the abdominal aorta is the celiac artery (celiac trunk or truncus coeliacus), which is a short, unpaired artery that arises anteriorly at the midline at the level of T12. It gives origin to the left gastric, splenic, and common hepatic arteries, which supply the abdominal esophagus, stomach, duodenum, spleen, liver, and pancreas. Of surgical anatomic significance, the splenic vessels course Chapter 75 Surgical, Radiographic, and Endoscopic Anatomy of the Retroperitoneum 1669. Cross-sectional anatomy of the upper abdomen at the level of the kidneys demonstrated with transverse sections obtained by computed tomography. When the inferior pancreatic edge is mobilized off the anterior renal fascia during adrenal or renal transperitoneal surgery, knowledge of the anatomic relationship between the splenic vessels and the pancreas is important to prevent vascular injury. The next branches are the paired middle adrenal arteries, which supply the ipsilateral adrenal gland as noted earlier. It supplies the pancreas (inferior pancreaticoduodenal artery), small intestine, and most of the large intestine (ileocolic, right colic, and middle colic arteries). The inferior adrenal arteries branch off the renal arteries to supply the ipsilateral adrenal gland. There is considerable variation in the location, size, and number of renal arteries, with at least one quarter of cases manifesting with supernumerary renal arteries. There is no clear consensus on whether supernumerary arteries are more common on the right or the left. Chapter 75 Right renal artery Aorta Left renal artery Surgical, Radiographic, and Endoscopic Anatomy of the Retroperitoneum 1671. Magnetic resonance angiogram, transverse section, right and left renal arteries arising from the aorta and supplying the kidneys. The gonadal arteries are the next paired branch of the aorta, typically arising anterolaterally from the aorta below the renal arteries. They may emerge from the renal artery in some variations, in which case they course with the gonadal vein. In males, the gonadal arteries are called the testicular arteries, and in females, they are called the ovarian arteries. The ovarian arteries arise from the anterolateral aspect of the aorta below the renal arteries. They travel anterior to the ureter and course medially as they pass through the infundibulopelvic ligament (suspensory ligament of the ovary) to the ovary. There are extensive collaterals to the gonads in both sexes, allowing for ligation of the testicular and ovarian arteries without gonadal ischemia. The paired lumbar arteries arise posteriorly, adjacent to the bodies of the upper four lumbar vertebrae. In some instances, a fifth pair of lumbar arteries is present, arising from the middle sacral artery. The superior hemorrhoidal artery has collateral circulation with the inferior and middle hemorrhoidal arteries, which branch off the internal iliac arteries. Before bifurcation, the median sacral (middle sacral) artery arises from the posterior aspect of the aorta and courses over the fifth lumbar vertebra and sacrum. At the fourth lumbar vertebra, the aorta bifurcates to form the common iliac arteries. No named branches are given off as these arteries enter the pelvis and divide to form the internal and external iliac arteries. Most often, the renal artery supplies the proximal ureter, and the internal iliac artery, including its branches, the superior and inferior vesical arteries, supply the distal ureter. The middle ureter is typically supplied by the aorta; however, it may also be supplied by the common iliac, gonadal, uterine, middle rectal, and vaginal arteries. In general, the abdominal (proximal) ureter receives its blood supply medially, and the pelvic (distal) ureter receives its blood supply from a lateral direction. Venous System Although not as well defined, the layers of the venous system are similar to that of the arterial system. The layers from innermost to outermost are the intima, internal elastic lamina, media, external elastic lamina, and adventitia. As in the arterial system, the intima is composed of a layer of endothelial cells with subendothelial connective tissue. In the venous system, the internal and external elastic laminae are often poorly defined even in larger caliber vessels. The media layer of veins is significantly smaller than that of arteries and contains less vascular smooth muscle. Conversely, the venous adventitia is larger than the venous media and functions similar to the adventitia of the arterial system. The venous system also differs from the arterial system with the presence of valves that prevent retrograde flow. These valves are typically bicuspid, and they function to maintain the full venous blood flow toward the heart. The venous system is more variable than the arterial system; however, many venous structures run parallel with their arterial equivalent. The median (middle) sacral vein runs with its respective artery and typically drains into the left common iliac vein; however, it may enter into the angle created by convergence of the two common iliac veins.

Through coagulating semen erectile dysfunction drugs injection buy discount sildalist online, seminal vesicle secretions may promote sperm motility impotence occurs when purchase sildalist without prescription, increase stability of sperm chromatin impotence natural treatments sildalist 120mg buy low price, and suppress immune activity in the female reproductive tract erectile dysfunction caffeine sildalist 120mg buy amex. The best-elucidated function of human semen is its ability to provide antioxidative protection to sperm erectile dysfunction doctor atlanta 120 mg sildalist purchase with amex. Semen is rich in antioxidant enzymes, including glutathione peroxidase, superoxide dismutase, and catalase (Yeung et al. In addition, the antioxidant molecules taurine, hypotaurine, and tyrosine are present in high concentrations (van Overveld et al. Lipofuscin granules from dead epithelial cells give seminal vesicle secretions a yellow-white color. In addition, seminal vesicle secretions are alkaline and contain fructose, mucus, vitamin C, flavins, phosphoryl choline, and prostaglandins. The mixing of seminal vesicle with prostatic secretions results in human semen having a mildly alkaline pH. It also contains the mitochondrial sheath, which is helically arranged around the outer dense fibers. The outer dense fibers, rich in disulfide bonds, are not contractile proteins but are thought to provide the sperm tail with the elastic rigidity necessary for progressive motility (Oko and Clermont, 1990). The sperm terminates in the endpiece, the most distal segment of the sperm tail, and contains axonemal structures and the fibrous sheath. Except for the endpiece region, the sperm is enveloped by a highly specialized plasma membrane that regulates the transmembrane movement of ions and other molecules (Friend, 1989). Mitochondria are organelles that produce cellular energy and can also cause apoptotic cell death through the release of cytochrome c. The inner membrane forms deep folds into the matrix, called the cristae, which make the surface area of the inner membrane larger than that of the outer membrane. Reasons for this may include the fact that mitochondria are near respiratory-chain complexes and may be easily attacked by reactive oxygen species. This degradation is likely mediated by the small proteolytic polypeptide ubiquitin, which regulates proteolysis in many tissues (Sutovsky et al. From animal studies, it is clear that the plasma membrane covering the sperm-head region harbors specialized proteins that participate in sperm-egg interaction (Saling, 1989). Physiologically, the axoneme is the true motor assembly and requires 200 to 300 proteins for proper function. The dynein proteins extend from one microtubule doublet to the adjacent doublet and form the inner and outer arms of the axoneme. The dynein structure has two or three globular, outer (heavy) chain heads (500 kD) joined to a common stem. The inner (light) chain arms (14 to 120 kD) are the primary effectors of movement and are associated with the radial spokes of the dynein assembly. Sperm with outer arm mutants have reduced motility, and those with inner arm mutants have no motility. Radial links or spokes connect a microtubule of each doublet to the central inner doublet and consist of a complex of proteins. The central inner doublet is surrounded by a ringlike helical sheath to which the radial links from the outer doublets are attached. Tektins are proteins associated with the outer microtubular doublets, and nexin links are proteins that connect the outer doublets to one another and maintain the cylindric axonemal shape. The phenotype of defective sperm structure has been recognized as ciliary dyskinesia. Although infertility is the rule with ciliary dyskinesias, ejaculated sperm can be motile and sperm concentrations can be normal. In general, patients suspected of harboring sperm structural defects exhibit severely compromised sperm motility (<10%). Sperm electron microscopy can reveal ultrastructural or functional sperm abnormalities. Sperm structural abnormalities are currently categorized by Chemes (2000) as follows: 1. This is the most frequent flagellar anomaly underlying severely low motility and shows a structural phenotype of random, heterogeneous, microtubular alterations. These anomalies can arise from correctable disorders such as varicocele, reactive oxygen species, and gonadotoxin exposure. This condition is a systematic sperm abnormality, usually associated with near-complete or total immotility. It has a more homogenous and distinctive phenotype characterized by sperm fibrous sheath, axonemal, and periaxonemal distortions. A subset of these patients exhibit the classic ciliary dyskinesia (formerly immotile cilia syndrome) in which sperm immotility is associated with respiratory disease and dextrocardia. There is a strong familial incidence, suggesting that such conditions are genetic. Sperm production in the testis functions optimally at 2°C to 4°C below body temperature and generates mature human sperm in 64 days. Well-integrated cycles and waves of spermatogenesis ensure that human sperm production is constant at about 1200 sperm per second. Spermatogenesis is an androgen-dependent process that occurs with very high intratesticular testosterone levels. The product of spermatogenesis, the spermatozoa, leave the testis as immotile cells with limited capacity to fertilize oocytes. After epididymal transit, sperm are typically motile and capable of fertilization. During ejaculation, sperm are rapidly transported through the ejaculatory ducts into the urethra from the distal epididymis. The ejaculate supports sperm metabolism and motility, serves as an antioxidant, and acts as a barrier to exclude subsequent gamete deposits from gaining access to the egg. Effect of unilateral vasectomy and ejaculation frequency on sperm reserves: aspects of epididymal physiology, J Reprod Fertil 3:260­268, 1961. Ben-Rafael Z, Orvieto R: Cytokines-involvement in reproduction, Fertil Steril 58:1093, 1992. Cayan S, Schriock E, Conaghan J, et al: Birth after intracytoplasmic sperm injection using testicular sperm from men with Kartagener/immotile cilia syndrome, Fertil Steril 76:1, 2001. In Bollack C, Clavert A, editors: Progress in reproductive biology, Basel, 1981, Karger, pp 48­57. Clement K, Vaisse C, Lahlou S, et al: A mutation in the human leptin receptor gene causes obesity and pituitary dysfunction, Nature 392:398­401, 1998. Clermont Y: the cycle of the seminiferous epithelium in man, Am J Anat 112:35­51, 1963. Clermont Y: Kinetics of spermatogenesis in mammals: seminiferous epithelium cycle and spermatogonial renewal, Physiol Rev 52:198­236, 1972. Collin O, Lissbrant E, Bergh A: Atrial natriuretic peptide, brain natriuretic peptide and c-type natriuretic peptide: effects on testicular microcirculation and immunohistochemical localization, Int J Androl 20:55­60, 1997. Conrad S, Renninger M, Hennenlotter J, et al: Generation of pluripotent stem cells from adult human testis, Nature 456:344­349, 2008. In Bollack C, Clavert A, editors: Progress in reproductive biology, Basel, 1981, Karger, p 67. Culty M, Li H, Boujrad N, et al: In vitro studies on the role of the peripheraltype benzodiazepine receptor in steroidogenesis, J Steroid Biochem Mol Biol 69:123­130, 1999. Hundeiker M: Lymphgefasse in parenchym des menschlichen hoden, Arch Klin Exp Dermatol 235:271, 1971. In Burger H, de Kretser D, editors: the testis, New York, 1981, Raven Press, pp 141­169. Kiess W, Reich A, Meyer K, et al: A role for leptin in sexual maturation and puberty Kinoshita Y, Hosaka M, Nishimura R, et al: Partial characterization of 5a-reductase in the human epididymis, Endocrinol Jpn 27:277­284, 1980. Kormano M: Dye permeability and alkaline phosphatase activity of testicular capillaries in the postnatal rat, Histochemie 9:327­338, 1967. Kormano M, Reijonen K: Microvascular structure of the human epididymis, Am J Anat 145:23­27, 1976. Kormano M, Suoranta H: An angiographic study of the arterial pattern of the human testis, Anat Anz 128:69­76, 1971. Kossack N, Meneses J, Shefi S, et al: Isolation and characterization of pluripotent human spermatogonial stem cell-derived cells, Stem Cells 27:138­149, 2009. Le Roy C, Lejeune H, Chuzel F, et al: Autocrine regulation of Leydig cell differentiated functions by insulin-like growth factor I and transforming growth factor beta, J Steroid Biochem Mol Biol 69:379­384, 1999. Filippini A, Riccioli A, Padula F, et al: Control and impairment of immune privilege in the testis and in semen, Hum Reprod Update 7:444­449, 2001. Temperature and androgen as determinants of the sperm storage capacity of the rat cauda epididymis, Biol Reprod 26:673­682, 1982. Goffin V, Binart N, Touraine P, et al: Prolactin: the new biology of an old hormone, Annu Rev Physiol 64:47­67, 2002. Hansson V, Djoseland O: Preliminary characterization of the 5-dihydrotestosterone binding protein in the epididymal cytosol fraction: in vivo studies, Acta Endocrinol 71:614­624, 1972. Hermo L, Lalli M, Clermont Y: Arrangement of connective tissue elements in the walls of seminiferous tubules of man and monkey, Am J Anat 148:433­446, 1977. Milgrom E, de Roux N, Ghinea N, et al: Gonadotrophin and thyrotrophin receptors, Horm Res 48:33­37, 1997. Muller I: Kanalchen und Capillararchitektonik des ratten Hodens, Z Zellforsch 45:522­537, 1957. Murakami M, Yokoyama R, Nishida T, et al: Scanning and transmission electron microscope observations of the terminal segment of the cat seminiferous tubule: epithelial phagocytosis of spermatozoa and latex beads, Arch Histol Cytol 51:185­192, 1988. Nikolic A, Volarevic V, Armstrong L, et al: Primordial germ cells: current knowledge and perspectives, Stem Cells Int 2016:1741072, 2016. Paniagua R, Regader J, Nistal M, et al: Histological, histochemical and ultrastructural variations along the length of the human vas deferens before and after puberty, Acta Anat 111:190, 1981. Prader A: Testicular size: assessment and clinical importance, Triangle 7:240­243, 1966. Primakoff P, Hyatt H, Tredick-Kline J: Identification and purification of a sperm surface protein with a potential role in sperm-egg membrane fusion, J Cell Biol 104:141­149, 1987. Rikmaru A, Shirai M: Response of the human testicular capsule to electrical stimulation and to autonomic drugs, Tohoku J Exp Med 108:303­304, 1972. Robaire B, Hermo L: Efferent ducts, epididymis, and vas deferens: structure, function, and their regulation. In Knobil E, Neil J, editors: the physiology of reproduction, New York, 1988, Raven Press, pp 999­1080. Robert M, Gagnon C, Semenogelin I: A coagulum forming, multifunctional seminal vesicle protein, Cell Mol Life Sci 55:944­960, 1999. Russell L, Clermont Y: Anchoring device between Sertoli cells and late spermatids in rat seminiferous tubules, Anat Rec 185:259­278, 1976. Wenzel J, Kellermann P: Vergleichende untersuchungen uber das Lymphgefasssytem des Nebenhodens und Hodesn von Mensch, hund unk Kaninchwen, Z Mikrosk Anat Forsch 75:368­387, 1966. Witschi E: Migration of the germ cells of human embryos from the yolk sac to the primitive gonadal fold, Carnegie Institute Wash Contrib Embryol 209:67­80, 1948. Suppression by abdominal temperature of transepithelial ion and water transport in the cauda epididymidis, Biol Reprod 26:683­689, 1982. Schulze W: Structural principles underlying the spermatogenic process in man and a non-human primate (Macaca cynomolgus). Schweitzer R: Uber die Bedeutung der Vascularisation, der Binnendruckes und der Zwischenzellen fur die Biologie des Hodens, Anat Entwickl 89:775­796, 1929. Steinberger E: Molecular mechanisms concerned with hormonal effects on the seminiferous tubule and endocrine relationships at puberty in the male. Sutovsky P, Moreno R, Ramalho-Santos J, et al: Ubiquitin tag for sperm mitochondria, Nature 402:371­372, 1999. Suzuki F, Nagano T: Development of tight junctions in caput epididymal epithelium of mouse, Dev Biol 63:321, 1978. In Burger H, de Kretser D, editors: the testis, New York, 1981, Raven Press, pp 107­126. Tiepolo L, Zuffardi O: Localization of factors controlling spermatogenesis in the nonfluorescent portion of the human Y chromosome long arm, Hum Genet 34:119­124, 1976. Toyama Y: Actin-like filaments in the myoid cell of the testis, Cell Tissue Res 177:221­226, 1977. Yanagimachi R: Fertilization and developmental initiation of oocytes by injection of spermatozoa and pre-spermatozoal cells, Ital J Anat Embryol 110:145­150, 2005. The importance of an ageing process in sperm for the length of the period during which fertilizing capacity is retained by sperm isolated in the epididymis of the guinea pig, J Morphol 48:475­491, 1929. Despite these differences, attention from health policy leadership and local, national, and supranational entities toward addressing this issue has remained scant. Efforts to reduce gender inequality in health are desperately needed and require a substantial adjustment in multiple facets of life, including workplace safety, global peace, sociology, psychology, and lifestyle. Gender Longevity Gap Human longevity continues to increase on a global scale (Fries, 1980; Oeppen and Vaupel, 2002). Emphasis on perinatal care, labor and delivery, childhood vaccinations, smoking cessation, and healthier lifestyles in terms of diet and exercise have made a true impact on extending human life span around the world (Mathers and Loncar, 2006; Oeppen and Vaupel, 2002). Interestingly, one peculiar statistic seems to stand out from the general progress: the gap in longevity between male and female humans. The gap exists across the globe and across all strata of industrial development; eastern Europe demonstrates the largest gap, approximately 7 years. Even in sub-Saharan Africa, the region with the shortest life expectancy in the world, men are living on average 5. In addition to the discrepancy present in current statistics, trends recorded over the past 50 years do not demonstrate a narrowing of the longevity gap.

The 16-dot procedure has become a popular variation of tunical shortening in which there is no incision into the tunic but the tunica albuginea is plicated with permanent suture using an extended Lembert-type suture placement technique (Brant et al erectile dysfunction doctors huntsville al 120mg sildalist with mastercard. Here erectile dysfunction diabetes qof purchase sildalist 120 mg with visa, a partial-thickness incision is made transversely on the contralateral side to the point of maximum curvature (Baskin and Duckett doctor for erectile dysfunction in chennai sildalist 120 mg order overnight delivery, 1994; Levine erectile dysfunction doctor in mumbai order sildalist overnight delivery, 2006) new erectile dysfunction drugs 2013 purchase sildalist us. The longitudinal fibers between the two transverse incisions are excised so as to reduce the bulk of the plication. The key is that all plication procedures shorten the long side of the penis and therefore can result in loss of length on that aspect of the penis. Studies have examined the loss of penile on rigidity, simple and safe surgery, and effective straightening (Hatzimouratidis et al. A study of failures with the Nesbit procedure identified three factors associated with an unsatisfactory outcome, including impaired preoperative erectile function, penile shortening of greater than 2 cm, and penile deformity greater than 30 degrees (Andrews et al. This technique uses excision of an elliptical segment of the tunica on the contralateral side of the curvature. Multiple variations on this approach have evolved, including the Yachia procedure, which uses the HeinekeMikulicz technique (Yachia, 1990, 1993). This approach must be used carefully so that the length of the incision is not too long, such that transverse closure could result in further narrowing of the shaft, possibly resulting in an unstable erection. Several authors have suggested that this approach has a lower risk for perceived penile shortening (Klevmark et al. Imbrication procedures are used to avoid making a full-thickness tunical incision and fold the tunica to correct curvature. The tunica albuginea is plicated with permanent suture using an extended Lembert-type suture placement following four dots per plication. The incision is made through the longitudinal fibers but does not violate the inner circular fibers of the tunic. The expected factors that predicted loss of length included the direction of curvature and the degree of curvature (Greenfield et al. Preoperative penile length and degree and direction of curvature deformity appear to correlate with postoperative satisfaction (Mulhall et al. It does not address hinge or hourglass effect and may exacerbate it, resulting in an unstable penis. Penile narrowing or indentation has been reported in up to 17% with these techniques. In addition, there can be pain associated with the knots and suture granulomas (Ralph et al. Surgical straightening with plication procedures can be expected in 79% to 100% of patients, with a reported satisfaction rate of 65% to 100% (Ding et al. Recurrence of penile curvature deformity (greater than 30 degrees) has been reported in up to 12% in a limited number of long-term studies (Levine and Burnett, 2013; Taylor and Levine, 2008). Other, less common complications include hematoma in up to 9% of patients, urethral injury in less than 2%, and phimosis in up to 5% (Kadioglu et al. This can be determined during the patient interview, when he is asked directly, "If your penis was straight, would the quality of rigidity that you currently have allow penetrative sex Some men simply reject the idea that they need a prosthesis as a first-line surgical treatment. Others who might be considered candidates for tunica plication reject this approach because of fear of penile length loss. These men may be offered a grafting repair with the understanding that a penile prosthesis can be placed with minimal added difficulty at a later time. The advantage of performing the grafting procedure is that it would likely correct curvature and reestablish more normal shaft caliber while increasing the likelihood of some length recovery in the range of 0. These predictors have been suggested as a result of single-center studies, with a limited number of patients in each cohort. Larger-scale studies indicate that the most critical criterion for any grafting procedure is the quality of preoperative erections (Flores et al. Expert opinion has been consistent that patients with ventral deformity do not do well with grafting procedures. Therefore, plaque incision was introduced in which a modified-H or double-Y incision is made in the area of maximum curvature (Gelbard, 1995). Using the modified-H incision allows the correction of the curvature and shaft caliber. Gelbard (1995) has suggested that using multiple incisions and filling them with grafts would result in a smoother correction of curvature and potentially less injury to the underlying cavernosal tissue (Gelbard, 1995). An increasing number of patients with severe deformity have indentation that if not addressed may result in a straightened penis but with residual narrowing causing instability. The corners of the defect are darted in a radial fashion to enhance correction of the narrowing in that area (Levine, 2011). Geometric principles have been applied to the grafting technique so as to obtain a properly sized graft with excellent correction of deformity (Egydio et al. Graft Materials the ideal graft should approximate the strength and elastic characteristics of normal tunica albuginea; should have minimal morbidity and tissue reaction; should be readily available; should not be too thick; should be pliable, easy to size and suture, inexpensive, and resistant to infection; and should preserve erectile capacity (Gur et al. Multiple autologous grafts have been used historically, including fat, dermis, tunica vaginalis, dura mater, temporalis fascia, saphenous vein, crura or albuginea, and buccal mucosa (Das, 1980; Devine and Horton, 1974; Hatzichristodoulou et al. Although the outcomes of these surgeries are typically good in select patients, they have fallen out of favor because of a need for extended surgery to harvest the graft and a second surgical site, which possesses its own potential complications of healing, scarring, and possible lymphedema. Crural and buccal grafts are compromised by the inability to get enough graft material for large defects (Hatzichristou and Hatzimouratidis, 2002; Schwarzer et al. Finally, "off-the-shelf" allografts and xenografts have emerged, including processed pericardium from a bovine or human source, porcine intestinal submucosa, and porcine skin. These packaged processed grafts are being used with increased frequency Chapter 73 because of their ease of use and reduction in operating times. The pericardial grafts are thin, are strong, do not contract, and have no reports of infection or rejection. Overall, 92% of patients were able to achieve successful coitus with or without assistance. These researchers reported a 33% overall recurrence rate, with 26% of patients who received dermal grafts and 44% of patients who received pericardial grafts experiencing recurrence. However, this study did not report on the severity of recurrence, and all patients were able to achieve erections suitable for coitus. Satisfaction rates were similar, and those who underwent pericardial grafting had shorter operative times and decreased morbidity associated with the absence of a graft donor site (Chun et al. However, a contemporary series showed that of 26 patients, there was 82% patient satisfaction and only 1 of 26 patients had a surgical complication (infected hematoma) (Valente et al. They concluded that this tissue-engineered endothelialized tubular graft was structurally similar to normal tunic with a high burst pressure and adequate mechanical resistance. Furthermore, the autologous property of this model could represent an advantage compared with other available grafts (Imbeault et al. The biomechanical properties, compatibility with the tunica albuginea, and effective neovascularization of the tissue-engineered grafts need to be investigated further before such basic research can be applied in practice. Tachosil is a collagen fleece coated with a tissue sealant that adheres to tissue after several minutes of compression. Because no surgical fixation is required, collagen fleece is easy to administer, and may shorten operating time. At a mean follow-up of 25 months, there were no major complications and recurrence was observed in only 16. An artificial erection is then created by injecting a vasoactive drug (papaverine, Trimix, prostaglandin E1) via a 21-gauge butterfly needle placed through the glans into the corpus cavernosum. Saline can be infused to create a full rigid erection, which allows visualization and measurement of the deformity, including curvature and areas of indentation with or without hinge effect. The preferred approach for grafting procedures is a circumcising incision made approximately 1. The penis is degloved down to the Buck fascia, at which point hemostasis is obtained with bipolar cautery. It is advisable for the surgeon to use loupe magnification to reduce the likelihood of injury to neurovascular structures. With the shaft exposed, the erection can again be re-created, demonstrating the area of maximum deformity. In the circumstance of a dorsal or dorsal-lateral curvature, the Buck fascia, with the enclosed neurovascular bundle, is elevated by making a pair of parallel incisions just lateral to the urethral ridge, through the Buck fascia to the tunica albuginea. Typically this can be done with delicate, sharp dissection, but occasionally, if there is significant adhesion between the Buck fascia and the tunic, bipolar cautery can be used to elevate this with minimal risk for permanent nerve injury. Once the Buck fascia is elevated off the area of maximum deformity, a full erection is re-created. It should be noted that even with a pure lateral curvature, the tunic to be excised must traverse through the dorsal septum, because this is the anchor point of the scar and if it is not taken, substantial residual curvature will likely remain (Jordan, 2007). When extensive calcification extends beyond the area of partial plaque excision, the calcified component can be removed, leaving the outer lamina intact because the calcification involves the inner circular fibers. Once the rectangular defect is established, the corners are darted in a radial fashion so as to help to recover normal shaft caliber in the area of indentation. Several authors have simplified the geometric principle technique by ensuring that the lateral sides of the defect are of equal length (Egydio et al. In doing this, we create a uniform-sized square or rectangle, which virtually always allows satisfactory correction of lateral and dorsal curvature. Often the proximal transverse length will be longer than the distal transverse length because of distal tapering of the shaft. The penis can now be measured on stretch again; typically there will be increased dorsal length from 0. With these stay sutures on stretch, the defect can be measured longitudinally and transversely. The graft should be sized no more than 10% larger than the measured defect on stretch. An artificial erection is again reestablished; if there is significant residual curvature, this can be addressed with tunica plication. In patients who have a more prolonged curve or in those who have substantial indentation in one area and a more distal curvature, the grafting should be performed in the area of indentation, and plication is used to address any residual dorsal or lateral curve once grafting has been completed. Once satisfactory deformity correction has been accomplished, the Buck fascia is reapproximated with running 4-0 chromic, and the shaft skin is reapproximated to subcoronal skin with interrupted 4-0 chromic in a horizontal mattress fashion. Of note, for those patients who are uncircumcised and do not have any evidence of phimosis, a circumcision is not necessary (Garaffa et al. Additional straightening maneuvers may be necessary, including manual modeling and incising of the tunica albuginea with or without grafting. Recently, transcorporeal approaches have been used before modeling or relaxing incisions; the plaque is incised or stretched from within the corporeal body (Perito and Wilson, 2013; Shaeer, 2011). Typically the dressing is left in place for 3 days and then removed, at which point the patient may shower. Submersion of the wound is not advised because this may encourage wound separation. We find it useful to liken the importance of postoperative rehabilitation after penile surgery to the importance of the rehabilitation needed for successful orthopedic joint replacement. Typically, a patient is seen 2 weeks after surgery, at which point massage and stretch therapy are initiated (Horton et al. The patient is instructed to grasp the penis by the glans and gently stretch it away from the body and then with his other hand to massage the shaft of the penis for 5 minutes twice per day for 2 to 4 weeks. This will reinitiate the sexual experience for the couple and hopefully diminish the fear of reinjuring the penis, for which the partner may feel responsible. Finally, external penile traction devices have been encouraged and have been recently shown to reduce length loss postoperatively and can even enhance length gain after both grafting and plication procedures (Levine et al. There was no patient reported with postoperative length loss among those who used postoperative traction therapy, and although not statistically significant, there was a trend of higher satisfaction for erect length in the groups in which postoperative traction was used. Traction is recommended to be used for 3 or more hours per day, beginning 3 to 4 weeks after surgery, once the wound can tolerate the pressures of the stretching device for 3 months (Rybak et al. Diminished sensation after grafting has been reported in a few series with a follow-up of less than 5 years (Taylor and Levine, 2008). Manual modeling via the penoscrotal approach is recommended with a high-pressure inflatable cylinder, but all available three-piece and two-piece devices have been used successfully to correct deformity (Chung et al. Our approach is to place the prosthesis cylinders first, followed by closing of the corporotomies. With use of a surrogate reservoir attached to the pump tubing, the prosthesis can be filled to full rigidity, which will allow visualization of the deformity. To protect the pump from the high pressures that may occur during manual modeling, shodded hemostat clamps are applied to the tubing between the pump and the cylinders. It is recommended to try to hold the penis in this position for 60 to 90 seconds, but experience has suggested that approximately 30 seconds may be all that is possible. Once the modeling has been performed, the penis can be reassessed by instilling more fluid, reapplying the hemostats, and then performing the modeling procedure repeatedly until satisfactory curvature correction has been attained. The modeling technique should be a gradual bending rather than a violent maneuver, because this will reduce the likelihood of inadvertent tearing of the tunic or injury to the overlying neurovascular bundle. Urethral injuries during performance of this technique as a result of distal extrusion of the prosthetic cylinders at the fossa navicularis have been reported (Wilson and Delk, 1994; Wilson et al. To reduce the likelihood of this occurring, the bending hand should be placed on the shaft of the penis rather than on the glans, to avoid downward pressure on the tips of the cylinders. The other hand should be grasping the base of the penis with pressure over the corporotomies, which will provide support to this area and reduce the likelihood of disruption of the suture line. Published reports on the use of modeling have indicated that successful straightening can be expected in 86% to 100% with no higher incidence of device revision; sensory deficit after manual modeling is rare but remains a potential complication that should be discussed with the patient preoperatively (Chung et al. Although it would appear that for more severe curvature more advanced techniques are necessary, published experience has suggested that manual modeling may be used as first-line therapy for correction of curvature after prosthesis implantation (Chung et al.

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The epididymal duct would be approximately 6 m in length if it were stretched out. It winds within the epididymis to form the body and the tail of the epididymis, all of which are surrounded by a fibrous sheath. This article provides a general anatomic framework of the surgical, radiographic, and endoscopic anatomy of the normal male reproductive system. Because this chapter is dedicated solely to the anatomy of the male reproductive system, please refer to Chapter 109 for further description of pelvic anatomy, including bones, soft tissue, circulation, and innervation of the pelvis not directly related to reproduction. It is common for the right testis to hang lower than the left in approximately 85% of men. The dimensions of the normal testis include a length of 4 to 5 cm, a width of 3 cm, and a depth of 2. There is a small, pedunculated or sessile body at the upper pole of the testis, which is known as the appendix testis. A tough capsule envelops the testis, composed from external to internal of the visceral tunica vaginalis, the tunica albuginea, and the tunica vasculosa, before reaching the parenchyma of the testis. The tunica albuginea is composed of smooth muscle cells that pass through collagenous tissue (Langford and Heller, 1973). It is believed that these smooth muscle cells provide the testicular capsule with some ability to contract and may affect arterial flow into the testis. They may also promote the flow of seminiferous tubule fluid on its way out of the testis (Davis and Horowitz, 1978; Rikmaru and Shirai, 1972; Schweitzer, 1929). Arterial Supply There are three arterial supplies to the testis: the testicular (internal spermatic) artery, the artery of the vas deferens (deferential artery), and the cremasteric (external spermatic) artery (Harrison and Barclay, 1948). The testicular artery is the main blood supply to the testis, and its diameter is greater than the deferential and cremasteric arteries combined (Raman and Goldstein, 2004). The testicular artery arises from the abdominal aorta and descends in the intermediate stratum of the retroperitoneum to enter the internal inguinal ring. From its aortic origin, it crosses the psoas muscle and the ureter to reach the inguinal ring to enter the spermatic cord. As the testicular artery descends toward the testis, it branches into an internal artery and an inferior testicular artery and into a capital artery to the caput epididymis. There may be variation at the level of this branching, which has been found to occur within the inguinal canal in 31% to 88% of cases (Beck et al. In 31% of cases, there are two branches, and in 13% there are three or more branches of this artery (Kormano and Suoranta, 1971). Arterial anastomosis occurs at the head of the epididymis, allowing for a rich blood supply between the testicular and capital arteries. At the tail of the epididymis, arterial anastomoses are formed between the testicular, epididymal, cremasteric, and vasal arteries. The testicular arteries pass into the mediastinum testis and supply the tunica vasculosa in the anterior portion of the upper pole of the testis and the anterior, medial, and lateral portions of the lower pole of the testis. Therefore care must be taken not to devascularize the testis by passing a traction suture through the lower pole, as well as by performing testis biopsies in the medial or lateral surfaces of the upper pole to minimize the risk of vascular injury. The deferential artery derives from the internal iliac artery or from the superior vesical artery. The cremasteric artery Microanatomic Architecture the tunica albuginea invaginates into the testis to form the mediastinum testis, where vessels and ducts traverse the testicular capsule. The mediastinum testis sends septa that attach to the inner surface of the tunica albuginea to form 200 to 300 cone-shaped lobules, each of which contains one or more convoluted seminiferous tubules. Seminiferous tubules are coiled and long, with both ends typically ending in the rete testis. The seminiferous tubules contain germ cells and supporting cells, including Sertoli cells, fibrocytes, and myoid cells of the basement membrane. Each seminiferous tubule is U-shaped, but if a seminiferous tubule were stretched out from its convoluted form, each would measure nearly 1 m in length. The testosterone-producing Leydig cells are interdispersed in the loose tissue around the seminiferous tubules. The interstitial tissue includes Leydig cells, mast cells, macrophages, nerves, blood vessels, and lymphatic vessels. Microbeads injected retrograde through the rete testis into the seminiferous tubules demonstrating the tubular structure. Testicular microanatomic architecture with Leydig cells, seminiferous tubules, germ cells, Sertoli cells, basement membrane, and smooth muscle labeled at 10× magnification. Centrifugal arteries, which are the individual arteries supplying the seminiferous tubules, pass within the septa containing the seminiferous tubules and branch into arterioles that ultimately become intertubular and peritubular capillaries (Muller, 1957). Although in the case of testicular artery ligation, the deferential and cremasteric arteries can potentially provide adequate blood supply to the testis, atrophy and/or azoospermia has resulted from testicular artery ligation in adults and children. Men who have undergone vasectomy deserve special attention in preserving the testicular artery in future surgeries such as varicocelectomy because of the risk of having had the deferential artery compromised at the time of vasectomy (Lee et al. Note connections between the pampiniform plexus and the saphenous, internal iliac, and external iliac veins. Venous Drainage Unlike most other venous patterns in the human body, veins within the testis do not travel with their corresponding arteries. Small parenchymal veins drain into either a group of veins near the mediastinum testis or veins on the surface of the testis (Setchell and Brooks, 1988). These two groups of veins anastomose with each other and the deferential veins to form the pampiniform plexus. The pampiniform plexus is a network of testicular veins that anastomose as they ascend surrounding the testicular artery. This allows for a countercurrent heat exchange that cools the blood flow within the testicular artery. Ultimately, these veins join to form two or three veins at the level of the inguinal canal, and then they form one vein that ascends to drain into the inferior vena cava on the right and into the renal vein on the left side. Lymphatic Drainage Lymphatic channels from the testis drain into the para-aortic and interaortocaval lymph nodes. Nerve Supply Visceral innervation to the testis and epididymis arise in the renal and aortic plexuses and course alongside the gonadal vessels. This is autonomic innervation; the testis does not have any known somatic innervation (Mitchell, 1935). The pelvic plexus, in association with the vas deferens, offers additional gonadal afferent and efferent nerves (Rauchenwald et al. Three distinct anatomic distributions of nerves have been isolated within the spermatic cord and are thought to be the primary contributors in men with chronic orchialgia. Blood-Testis Barrier the fluid passing from the seminiferous tubules and exiting from the testis has been found to have a substantially different fluid composition than that of blood plasma or lymphatics. This suggests that compounds do not freely diffuse to and from the tubules, indicating that a barrier exists, which is known as the blood-testis barrier (Setchell and Waites, 1975). There are extremely strong, tight junctions between Sertoli cells, which provide an intracellular barrier that allows for spermatogenesis in an immune privileged site. Microsurgical view of the veins of the pampiniform plexus during varicocele ligation through a subinguinal approach. Ultrasonography Ultrasonography is the primary imaging modality used to interrogate the scrotum and its contents. The patient is placed in the supine position and a coupling gel is used with the transducer probe on the scrotal skin. An anechoic area between the echogenic scrotal wall and testicle is commonly visualized, which represents a small amount of physiologic fluid between the visceral and parietal layers of the tunica vaginalis. The mediastinum testis is visualized posteriorly as an echogenic band parallel to the epididymis. The echo pattern of the normal testis is fine, uniform, with a medium-level echo pattern. Sonographically, the normal testis measures approximately 5 cm × 3 cm × 2 cm (Dogra et al. Color Doppler can identify testicular vessels in the majority of patients (Spirnak and Resnick, 2002). Waveforms from intratesticular arteries and testicular capsular arteries demonstrate consistently low-impedance patterns with high levels of diastolic flow. Supratesticular arteries are also sonographically identifiable and show low-impedance waveforms from the testicular, deferential, and cremasteric arteries (Middleton et al.

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