Perirectal Space Research Articles

Anogenital lymphangioma circumscriptum masquerading as condyloma accuminata

Anogenital lymphangioma circumscriptum masquerading as condyloma accuminata

Radiological features of leiomyomatous tumors of the colon and rectum.

The purpose of this study was to evaluate the radiological features of 12 pathologically proven cases of colorectal leiomyomatous tumors. A retrospective analysis of radiologic findings was performed in 12 patients with pathologically proven colorectal leiomyomatous tumors (2 leiomyomas and 10 leiomyosarcomas). Available radiologic studies included abdominal CT scans in 11 patients, double contrast barium studies in 4, and pelvic MRI in 1. On imaging, we evaluated the size, tumor margin (smooth or lobulated), morphologic appearance, growth patterns (endocolic, exocolic, or combined), contrast enhancement patterns, presence or absence of calcification within the tumors, and metastasis. The involved tumor sites were the colon in 2 patients and the rectum in 10. The mean tumor size was 7.9 cm (range 2-15 cm): It was 3.5 cm in leiomyomas and 8.8 cm in leiomyosarcomas. On imaging studies, the tumor margin was smooth in three patients and lobulated in nine, with endocolic growth in one, exocolic in four, and combined in the remaining seven. Eight of the 12 tumors showed varying degrees of internal necrosis with heterogeneous contrast enhancement. Dystrophic calcification was noted in five patients. Metastasis was seen in the liver in three patients at the time of initial diagnosis, and lymphadenopathy was noted in two patients (paraaortic space in one and perirectal space in two). Although rare, the diagnosis of leiomyomatous tumor may be suggested especially when the tumor occurring in the colorectum shows exocolic growth or calcification with varying degree of internal necrosis.

Rectal carcinoma: double-contrast MR imaging for preoperative staging.

To evaluate and compare the imaging findings and staging of rectal carcinoma by using conventional magnetic resonance (MR) imaging, MR imaging with an enema of superparamagnetic ferristene-based contrast material, and MR imaging with an enema of ferristene solution plus intravenous injection of gadodiamide. Twenty-nine patients (17 women, 12 men; age range, 39-91 years) referred with a diagnosis of rectal carcinoma were examined. Analysis of the rectal wall and staging of the tumor were performed. In all patients, the MR imaging findings were correlated with the histopathologic findings. The contrast material enema caused distention of the rectum and an intraluminal signal void, whereas the gadodiamide injection caused enhancement of the mucosa on T1-weighted images. This enhancement enabled evaluation of the normal rectal wall and differentiation of the mucosa, tunica muscularis, and perirectal space, which was not possible on the nonenhanced images. Double-contrast (ferristene solution plus gadodiamide) MR imaging was superior to imaging with only ferristene-based contrast material and had a sensitivity of 100%, specificity of 70%, and accuracy of 90% in distinguishing tumor stages worse than Dukes A. Double contrast material-enhanced MR imaging enables accurate rectal carcinoma staging, which is not possible at nonenhanced imaging.

Lipomatosis pélvica: revisión clínica y aportación de cuatro nuevos casos

First described by the end of the fifties, pelvic lipomatosis is an uncommon disease that develops as a result of an excessive proliferation of benign fat tissue within the perivesical and perirectal spaces. The compressive effect on the urinary, and to a lesser degree, the digestive and vascular structures result in the well-known symptoms. Diagnosis is reached through X-ray studies, primarily computerised tomography. Contribution of four new cases in young males diagnosed through imaging studies as well as biopsies in three of them. Evolution has been varying, with medical control of symptoms in two cases and renal function impairment due to upper obstructive uropathy in the other two.

Rectal Gangrene. A Rare Complication of Infected Hemorrhoid.

A 27-year-old male with rectal gangrene as a result of a hemorrhoid infection complicated by pelvic cellulitis is described. Management initially included an exploratory laparotomy and perirectal space drainage. The patient deteriorated acutely on the 2nd postoperative day and required emergency abdomino-perineal resection. Reviewing the medical literatures, rectal gangrene can occur as a result of variety of etiologies such as occlusion of small arteries, toxication, infection, or trauma, although most of them occur after the abdominal aortic operations. Because clinical deterioration occurs in a matter of hours, a high index of suspicion should be maintained and the emergency operation is always required to save patient's life.

Osteosarcoma of the Pelvis

The cases of 40 patients with osteosarcoma of the pelvis treated between 1977 and 1994 were reviewed. The location of the tumor was ilium in 30 patients, ischium in four, pubis in one, and sacrum in five. Most (58%) of the tumors were of the chondroblastic subtype. Thirty patients had surgical excision of the tumors: 10 with hemipelvectomies and 20 with limb sparing procedures. A wide margin was achieved in 16 of 30 (53%) patients, including 12 of 14 who had no sacral tumor involvement. Positive margins occurred at the sacrum in 11 patients, lumbar vertebra in one, perirectal space in one, and contralateral pubic body in one. Macroscopic tumor emboli within the regional large vessels were found in seven patients. The incidence of local recurrence was 32%: 13% in wide excisions, 38% in marginal excisions, and 80% in intralesional excisions. The 1- and 5-year overall patient survivals were 73% and 34%, respectively. Patients who had a surgical excision of the primary tumor had a significantly better survival than did those treated without surgery (5-year survival; 41% and 10%, respectively). Tumor size, surgical excision of the primary tumor, surgical margin, and type of surgical procedure were the prognostic factors for patients with Stage IIB tumors.

Saline Injection into the Perirectal Space to Assist Transgluteal Drainage of Deep Pelvic Abscesses

Saline Injection into the Perirectal Space to Assist Transgluteal Drainage of Deep Pelvic Abscesses

Preoperative staging of rectal carcinoma using double-contrast MR imaging. Technical aspects and early clinical experiences.

To improve preoperative staging of rectal carcinoma with MR imaging, using a double-contrast technique. Imaging was performed in 12 patients before and after i.v. injection of Gd-DTPA and rectal administration of a superparamagnetic contrast medium, mainly containing magnetite. The diagnostic information was evaluated and compared with findings at surgery and histopathological analysis. The superparamagnetic contrast medium enema caused a distension of the rectum and intraluminal signal void, whereas Gd-DTPA enhanced the mucosa in T1-weighted images. This allowed an evaluation of the normal rectal wall and separation of the mucosa, tunica muscularis and perirectal space in all cases, which was not possible in T1- or T2-weighted precontrast images. The rectal carcinoma could be delineated and tumor invasion to the rectal wall determined in all cases. The findings in postcontrast MR corresponded with the findings at histopathological examination in 11 of 12 patients. The histopathological examination in one patient revealed metastases (< 1 cm) in regional lymph nodes, too small to be identified in pre- or postcontrast MR images. Double-contrast-enhanced MR imaging allows evaluation of the normal rectal wall and preoperative staging of rectal carcinoma.

私の歩んできたこう門病学

Colo-Proctology Center was begun at the Department of Surgery of the Social Insurance Central Hospital in 1960. Patients with coloanal disease and number of surgeries have been gradually increased and number of patients treated at the Center were about 6, 000 and 848 instances underwent surgery in 1992.As for hemorroidal surgery, Whitehead's method had been performed in our department up to 1961, but since then Millingan-Morgan method and its modified methods have been performed.Ligation and Excision methods had been used for only 3.3 percent until 1958 in Japan but for 82.6 percent in 1977.As for fistula in ano, we presented threedimentional classification using symbols representing the extension of the fistula, sites of penetration in the sphincter and its relationship to the perirectal spaces (1972). This classification is used presently in the discussion of anal fiitula in Japan.A sphineter preserving method has been used on IIL (low inter sphincteric fistula) in which a fistulous tract is situated laterally or anteriorly to the anus. For II HC (complicated high inter sphincteric fistula) or type III (Ischiorectal fistula), conservative correction by P.H. Hanley (New Orleanse) has been used.In a treatment of anal fissure conservative methods have mostly been used ambulatory, lateral subcutaneous internal sphincterotomy has been performed in the patients with severe anal pain and only a few patients with chronic ulcer undergo surgery.As for postoperative disturbances, half of them are caused by Whitehead's method and the causes for recurrence of anorectal fistula were persistence of the primary lesion, persistence of fistula, remaining infective lesion, and inappropriate drainage.A conference on colo-proctology, in which discussion on one theme was frankly done, has been continuing, and it is useful for daily practice of colo-proctology, being well-received by doctors.Many doctors, who are interested in colo-protology, have visited the Colo-Proctology Center, after several training sessions, they have been encouraged in their work and have been trying to raise the level of knowledge and treatment in this field.

Cellular differentiation in relation to water vapour absorption in the rectal complex of the mealworm, Tenebrio molitor

Larvae of the mealworm beetle Tenebrio molitor, are able to absorb water vapour from subsaturated air, but adults cannot. This functional difference is paralleled by structural differences in the cryptonephridial rectal complex, the site of vapour absorption in the larva. Very distinctive differences occur in the rectal pad epithelium and these are reported in detail for the first time. The cells of the larval rectal pad are very closely apposed, forming a structural, and presumably functional, unit, whereas the cells of the adult rectal pad are more clearly separate. Intracellular organization also shows clear differences. These differences indicate that the rectal epithelium may play a more important role in vapour absorption than recently ascribed to it. Other, less striking, differences in the cryptonephric Malpighian tubules and perinephric membrane as previously recorded have largely been confirmed. Morphometric analysis suggests that diffusion alone could account for the observed absorption of water vapour across the larval system from rectal lumen to the lumen of the cryptonephric tubules, but this does not rule out the possibility that other transporting mechanisms are also involved. Radial diffusion and antero-posterior gradients may be facilitated by the predominently radial and circumferential arrangement of the rectal pad cells and the surrounding cryptonephric tubules. Reinvestigation of the isolating perinephric membrane and its insertion onto the rectal cuticle supports the conclusions that insertion occurs only posteriorly. The model incorporating anterior as well as posterior insertion does not apply. The membrane posteriorly encloses a single perirectal space between rectum and tubules and in this region no perinephric or peritubular space is found between inner and outer regions of the membrane. This is the region where maximal gradients occur across the system.

Radiologic features of retroperitoneal cystic hamartoma.

Retroperitoneal cystic harmartoma is a rare tumor believed to originate from small portions of the embryonic tailgut that normally disappear in early fetal development. Depending on the location and size of the mass, a wide range of clinical presentations is associated with the lesion. Most lesions are found in the presacrococcygealretrorectal space, but they may also occur in other retroperitoneal locations. Computed tomography (CT) is the most sensitive radiologic study for detecting these tumors, which usually are small, round, sharply marginated, and of homogeneous soft tissue density. We describe the clinical, radiographic, and pathologic features in four patients. In three cases, the lesions occurred in the perirectal space, and in one it was found in the iliac fossa. In this last case, there was an additional lesion in the perinephric region.

The fascial planes round the rectum. Anatomic and computer tomographic correlations (author's transl)

About 1000 patients mostly with rectal carcinomas but also with hematomas, abscesses and soft tissue tumors received CT-examinations of the posterior compartment of the pelvis before and after surgical treatment and radiation therapy. The morphology of the perirectal space is demonstrated under normal and pathologic conditions and can be compared with the current anatomical knowledge. Special attention has been focussed on the site of the so called "Hüllfaszien" or "Grenzlamellen" of the rectum and the division of the perirectal space. Nomenclature and description of the perirectal fasciae and spaces are somewhat controversial. Therefore misinterpretations of pathologic CT-findings are not uncommon.

The cryptonephridial system in the mealworm Tenebrio molitor: transport of radioactive potassium, thallium and sodium; a functional and structural study.

Larvae of the mealworm Tenebrio molitor were injected with radioactive potassium, sodium or thallium solution. It was found that the rectal complex of the animal was labelled with potassium and thallium, but not with sodium. Potassium and thallium labelled the complex to the same level as if the two ions were tracers for each other. Ramsay has found that potassium is actively transported to the complex from the hemocoel and there are reasons to believe that T1+ follows the same pathway. Therefore animals injected with thallium were investigated both by light and electron microscopy. The results suggest that thallium spreads from the hemocoel through the leptophragma to the neighbouring ordinary tubular cells, and in moist mealworms thallium is further found in the perirectal space. Due to diffusion and washing out of thallium during fixation it can not be determined whether T1+ and K+ follow identical pathways, but it is possible to determine how far thallium has penetrated during the experiments.

2. Classiflcation of Fistulas

Fistulas were classified into 4 main groups according to their spread to perianal or perirectal spaces, i.e., I-subcutaneous or submucous fistula, II-intersphincteric (between internal and external sphincters) fistula, III-infralevator fistula and IV-supralevator fistula.I and II groups were further divided into H (high) and L (low), setting the dentate line as a dividing line. III and IV groups were divided into U (unilateral) and B (bilateral). Each of them was also divided into s (simple) and c (complicated).Eight hundred and eight cases of fistulas operated in our clinic for the past 3 years were classified according to the above-mentioned criteria and shown in the following table (denominator in each column). Also shown in the same table are re-operation cases in each types-of fistulas (numerator) and re-operation rates (%).

Insect rectum

An important function of the rectum in terrestrial insects is the removal of water from the faeces, which in some insects are in equilibrium with an atmosphere of 75% relative humidity or less when they are voided. Structural complexity in the insect rectum appears to have evolved along two main lines: ( a ) The cryptonephric line; the ends of the Malpighian tubules are enclosed together with the rectum in a perirectal space. ( b ) The rectal gland line; areas of thickened epithelium have a system of intercellular channels and spaces. These two lines have in common that the perirectal fluid of ( a ) and the intercellular fluid of ( b ) are of higher osmolarity than the haemolymph, and it has been suggested that the reabsorption of water from the faeces is thereby facilitated. Possible mechanisms are discussed, with special reference to the active transport of water.

Further studies on the rectal complex of mealwormtenebrio molitor, L. (Coleoptera, Tenebrioidae)

An electron microscopical study has been made of the rectal complex. The perinephric membrane is a complicated structure which, in the posterior region, comprises an inner and an outer sheath separated by a space containing tracheolar end cells. The outer sheath is formed of a single layer of cells covered by an external basement membrane. The inner sheath is a multi-laminate structure made up of many thin, cellular layers which in places are reduced to closely apposed plasma membranes. Anteriorly the cellular layers are reduced in number, but each layer is of greater thickness; they finally terminate where the perinephric membrane is applied to the intestine. Posteriorly the inner sheath makes contact with the rectal epithelium. An earlier description identified three spaces within the rectal complex: the perirectal, subepithelial and peritubular spaces. The first two are true intercellular spaces, bounded by basement membranes, but the so-called peritubular space is occupied by necrotic cells. The inner sheath of the perinephric membrane is interrupted by the leptophragmata. Each leptophragma is bounded by a prominent electron-dense ring into which the laminae of the inner sheath are inserted. The outer sheath forms a blister over the leptophragma and is completely noncellular in this region. At the base of the blister a basement membrane covers the leptophragma itself, and the body of the leptophragma cell projects into the lumen of the tubule, with a thin layer of cytoplasm lying beneath the basement membrane. Both this layer and the cell body itself bear microvilli. The cell has a normal complement of mitochondria, but these do not invade the microvilli. In this last respect the ordinary tubule cells differ from the leptophragma cells in that most of their microvilli contain mitochondria, with connexions between the outer mitochondrial m em brane and the plasma membrane. The tubule cells have a poorly developed endoplasmic reticulum but are filled with numerous small granules; basal infoldings are restricted to those parts of the cell which face the perirectal space. The permeability of the perinephric membrane has been re-investigated and it is shown that the m em brane is more permeable to water and solutes at the anterior end, as might be expected if the inner sheath were the main barrier. Using preparations isolated in small volumes of haemolymph or other external media it has been shown that the rectal complex takes up potassium against a gradient of concentration. The lumen of the perirectal tubule is some 50 m V positive with respect to the external medium, so the uptake of potassium must be active. The leptophragma is freely permeable to chloride and this ion appears to enter the tubule passively. A model of the mechanism of the rectal complex is proposed, whose main feature is that the high osmolarity of the fluids within the rectal complex is brought about by the inward secretion of potassium chloride, unaccompanied by water, at the leptophragmata. This should result in a fall in the osmolarity of the external medium. A substantial fall has been observed on occasion, but in most experiments a fall is barely detectable. It is believed that the impermeability of the leptophragmata to water is rapidly lost in a deteriorating preparation.