Pathways of lymph flow through superficial inguinal lymph nodes in the pig

The pig lymph node has an unusual structure in that tissue containing lymph nodules generally occupies a central position. Our aim was to describe the lymphatic pathways through this node. We studied the structure of these pathways with light and electron microscopy, made casts of lymphatic vessels and sinuses with Microfil, and studied the distribution within the node of subcutaneously injected carbon particles. Most afferent lymphatics penetrate deeply within the node, where they give off several branches to peritrabecular sinuses that ramify through centrally located nodular tissue. However, where an afferent lymphatic enters the node there is a subcapsular sinus over an area of nodular tissue that occupies a conventional superficial position. Some lymph reaches this sinus from the central peritrabecular sinuses, but there can also be direct communications between this sinus and the afferent lymphatic. After flowing through sinuses in nodular tissue, lymph enters tissue that is analogous to medullary tissue in other species. This tissue is of two types, one consisting mainly of a diffuse network of reticular cells around spaces up to 10-12 microns across, and one that more closely resembles conventional medullary tissue. Lymph then flows to collecting ducts, which lack valves, and then to efferent lymphatics. Our findings do not support suggestions that a purely physical obstruction of lymphocytes in the lymph node accounts for the dearth of lymphocytes in efferent lymph of pigs.

Artifacts, normal variants, and imaging pitfalls of musculoskeletal magnetic resonance imaging

This article is an early attempt to catalogue some of the many artifacts, normal variants, and imaging pitfalls that the authors have seen in musculoskeletal MRI. The study of such phenomena is potentially very rewarding and may help to prevent some cases of misdiagnosis with MRI.

Intraperitoneal paravesical spaces: CT delineation with US correlation

The urinary bladder, obliterated umbilical arteries, and inferior epigastric vessels located within the extraperitoneal space of the anterior abdominal wall indent the anterior parietal peritoneum, forming intraperitoneal paravesical fossae. These are the supravesical space and the medial and lateral inguinal fossae. More posteriorly, the peritoneum covering the bladder is reflected onto the rectum to form the rectovesical space, which is divided by the uterus into an anterior vesicouterine recess and a posterior rectouterine pouch, or cul-de-sac. The cul-de-sac is continuous with the pararectal and ovarian fossae and is bounded posterolaterally by the rectouterine (sacrogenital) folds. These peritoneal compartments form a large potential space for the accumulation of ascites and are separated from the equally large extraperitoneal paravesical spaces by only a thin layer of peritoneum or peritoneum and umbilicovesical fascia. The computed tomographic scans of 100 patients with ascites were reviewed, with particular attention to the differentiation between intraperitoneal and extraperitoneal paravesical collections. The scans of intraperitoneal collections were found to have certain characteristic appearances, including inferior displacement of the distended urinary bladder, visualization of the umbilical folds, and preservation of the preperitoneal fat.

Anatomical basis of inguinal surgery in children

This paper begins with a review of the embryology of the inguinal region. The authors then point out the special morphological and topographical features of the inguinal canal in male children. These observations were based on the study of 50 inguinal canals from male children. From the anatomical observations described in this study guidelines are proposed for the surgical approach and dissection of the spermatic cord used in the treatment of congenital hernias or abnormal descent of the testis.

Inguinal hernia of childhood

The early recognition and treatment of the inguinal hernia in childhood should result in negligible morbidity and mortality with current anesthetic and recovery room support. The outpatient management of the postoperative patient has contributed to this objective as well as reduced the overall cost.

A gliding space between the femoral artery and inguinal ligament: mechanism of formation of false aneurysm

False aneurysms preferentially arise in the inguinal region subsequent to aorto-femoral bypass. This finding suggests that the position of the inguinal ligament against the anterior surface of the prosthesis may be an etiological factor. Description of the inguinal region, forming a borderline between the trunk and thigh and specific to the erect posture, has been the subject of many anatomical studies. These papers describe mainly the relations between the vascular sheath of the femoral artery, the fascia transversalis and inguinal ligament. Based on a series of anatomical dissections we have found a gliding space between the femoral artery and inguinal ligament. This finding has led us to propose section of the fibrous portion of the inguinal ligament and the insertion of free omentum between the arch of the ligament and prosthesis in order to prevent false aneurysm. Preliminary results obtained with this technique are satisfactory.

Inguinal hernia repair using local anaesthesia

This is a review of a large and long experience in one hospital with more than 100 000 elective inguinal hernia repairs using local anaesthesia and emphasising the advantages of this type of anaesthetic. Subsections deal briefly with facets of this experience such as age, preoperative assessment, skin incision, the cremaster muscle, the testis, bilateral hernias, hernias in women, short hospital stay, follow-up, return to work and recurrence rates. Considerable emphasis is given to the principles of technique and this is described in detail.

Radical ilioinguinal lymphadenectomy

Radical ilioinguinal lymphadenectomy remains the mainstay of treatment for certain genitourinary carcinomas either with the propensity for or with clinical evidence of metastases to the inguinal-pelvic region. The most frequent indication for this procedure in urologic practice is carcinoma of the penis, followed by carcinoma of the urethra, scrotum, and testis with scrotal invasion. This article reviews the anatomy of the inguinal and iliac region and presents a detailed discussion of the surgical technique.

A model of the inguinal canal

Medical students often find it difficult ot conceptualize and learn the anatomy of the inguinal region and canal. A model of the inguinal canal, appropriate for lecture and laboratory presentations, has been used for many years by one of the authors (J.J.J.), and based on student and staff feedback, is judged a successful visual learning aid. This paper outlines a step-by-step procedure for constructing the model out of plexiglass and colored, felt-tipped marking pens.

Inguinal herniography in adults: technique, normal anatomy, and diagnostic criteria for hernias

In 146 adults (88 men, 58 women) with groin pain of uncertain origin and normal physical examinations, herniography disclosed inguinal hernias in 40 (45%) men and in 19 (33%) women. There were no false-positive or false-negative herniographic diagnoses among 20 patients who were operated upon subsequently. These results indicate that herniography is a useful examination in the evaluation of adults with groin pain of obscure origin.

Lymphatic neovascularization after orchiopexy

Lymphatic neovascularization after transseptal and ipsilateral orchiopexy was studied in dogs. After the former, massive scrotal and inguinal lymphatic neovasculature developed on the side of the subcutaneous pouch; the lymphatic vessels drained into both right and left superficial inguinal, iliac, and paraaortic lymph nodes. After ipsilateral orchiopexy, neovascularization was confined mainly to the scrotum and inguinal areas of the affected side, although crossing to the opposite inguinal nodes was also seen. In the unoperated animal the lymph of the testicle was partially drained through the lymphatics of the epididymis and vas deferens into the iliac nodes.

Inguinal anatomy

The flat muscles of the anterior abdominal wall pass down well in front of the pectineal ligament of Astley Cooper on the summit of the superior pubic rumus, thus providing space for the spermatic cord and the great vessels of the lower limb to leave the abdomen. The abdominal wall layers turn back lower down to close the gap on the medial side of the external iliac vein. The external oblique aponeurosis turns back to form a strong inguinal ligament, and the attached fascia lata turns back as the lacunar ligament to meet and fuse with the pectineus muscle fascia 1-1.5 cm below Cooper's ligament. This leaves a deep trough, between Cooper's ligament behind and the posterior inguinal wall in front, which houses the transversely placed femoral canal. The transversalis fascia of the floor of the femoral canal turns down to form the medial wall of the venous compartment of the femoral sheath, and has the support of the curved edge of the lacunar ligament which effectively bars the femoral canal from entering the thigh. It is usually taught, however, that the lower end of the femoral canal passes unprotected into the thigh as the medial or third compartment of the femoral sheath, to lie between the femoral vein in its sheath and the curved edge of the lacunar ligament. If this were the case there would be no hindrance to the descent of a process of parietal peritoneum containing omentum or gut into and distending the femoral canal in the thigh. Would such a swelling, before the process of peritoneum had broken through the walls of the canal into the subcutaneous tissues of the groin, pass for a femoral hernia? Fortunately this problem does not arise. A study of the posterior aspect of the anterior abdominal wall, removed with the attached anterior half of the bony pelvis, reveals many details of the design and attachments of the deep inguinal ring, the femoral trough and canals and the femoral sheath.

Hormonal regulation of testicular descent: experimental and clinical observations

Hormonal regulation of testicular descent has been investigated. Based on experimental studies using the rat and on a review of clinical material it has been determined that testicular descent is an androgen-mediated event directly under the regulation of pituitary gonadotropin. Furthermore, the active androgenic metabolite involved in this process appears to be dihydrotestosterone, which is synthesized by the testis and must be present in high local concentrations to be effective. In addition to these hormonal requirements the anatomy of the inguinal canal must provide unimpeded migration of the testis into the scrotum. Any imbalance or anomaly of these prerequisites may lead to cryptorchidism.

[Age and variability in the inguinal lymph nodes of adult humans]

Lymphatic nodes on the anterior surface of the femur, in the region of the femoral triangle were studied in 56 corpses of humans of either sex from 31 to 82 years of age, dead of accidental causes or of diseases not related to lymphatic nodes. The investigation was carried on by the method of interstitial and direct injection of the Gerota's mass to some regions of foot skin, external genitalia and the skin of the anterior wall of the abdomen. It has been established that the size of inguinal lymphatic nodes (both superficial and profound) in humans of either sex, are in direct dependence on the age of the person. The amount of inguinal lymphatic nodes in young people prevails over that in old people. The external diameter of the afferent and efferent vessels in elderly humans is greater than in young ones. The amount of afferent lymphatic vessels to inguinal lymphatic nodes in most cases prevails over the amount of efferent ones, independent of age and sex. The external diameter of the former is greater than that of the latter.

The applied surgical anatomy of the peritoneal fascia of the groin and the "secondary" internal inguinal ring

The preperitoneal fascia of the groin is distinct from the transversalis fascia, although often mistaken for it. This distinction, and other special features of this fascia in the inguen, are more readily appreciated in the course of the preperitoneal approach than by the conventional transinguinal approach. Certain features of this fascia which are of practical surgical significance are emphasized, especially those concerning operations for hernias, hydroceles, or undescended testes in infancy and childhood. These special features include the preperitoneal fascial ring or secondary internal ring, which appears to have been confused in the past with the transversalis fascial opening or internal ring proper. Other features concerning the relative merits of the preperitoneal approach to groin hernias as opposed to the conventional transinguinal approach are discussed.

The inguinal and lacunar ligaments

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