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PubMed1985

[Anterior single-stage resection with a manual suture as the standard operation of the proximal and middle third of the rectum].

Of a total of 146 restorative resections 129 one-stage anterior resections were performed in a series of 203 tumours of the rectum. The hand-sutured one-layer anastomosis, well established for the upper third of the rectum, can be equally well effected after resection of the middle third. For this purpose the dissection of the extraperitoneal rectum is carried down as far as to the pectinate line, comparable to the abdominal phase of rectal excision. When the anococcygeal raphe is cut the pectinate line becomes visible upon traction and the anastomosis is readily established from within the abdomen. After release of traction it glides down into it's narrow final embedment in the depth of the pelvis from which a potential dehiscence never becomes apparent before the 7th postoperative day. By this time conservative management without protective colostomy is possible, provided absorbable suture material and adequate drainage are used. Dehiscence rate was 12.4%, operative mortality 1.5%. Single components of reliability of the anastomosis are particularly well visualized and controlled with the hand-suture technique.

Adenocarcinoma↗
PubMed1991

The vascular and neuronal composition of the lateral ligament of the rectum and the rectosacral fascia.

Detailed dissections were performed on 83 pelvic halves from 45 cadavers in order to obtain more accurate data on the composition of the lateral ligament of the rectum and the rectosacral fascia. The middle rectal artery was observed in only 18 out of 81 spcimens (22.2%). The lateral ligament of the rectum was divided into lateral and medial portions, according to the positional relationship to the pelvic plexus. The lateral part consisted of a superoanterior and an inferoposterior subdivision. The main component of the former was the middle rectal artery, while the pelvic splanchnic nerves were contained in the latter. Both compoents can be considered to contribute to the formation of the medial part, although the middle rectal vessels were not always present. The medial part consisted of the rectal branches from the pelvic plexus and their connective tissue. The rectosacral fascia was formed by dense connective tissue between the posterior wall of the rectum and the third and fourth sacral vertebrae. The main components of the fascia were branches of the lateral and median sacral vessels and the sacral splanchnic nerves which arose directly from the sacral sympathetic ganglia.

Blood Vessels↗
PubMed1988

Sympathetic nervous influence on the internal anal sphincter and rectum in man.

The effect of sympathetic nerve block and efferent stimulation of the sympathetic nerves on anorectal motility was studied in 21 patients undergoing operation for rectal carcinoma. Anal pressure and rectal volume were simultaneously recorded before and after epidural anaesthesia and during nerve stimulation. Efferent electrical stimulation of the presacral hypogastric nerves (HGN) elicited a contraction of the internal anal sphincter (IAS) in 13 out of 15 patients. The contraction was preceded by a relaxation in seven patients. In the rectum stimulation of the HGN caused variable responses. A weak contraction was the most frequent response. Efferent stimulation of the periarterial lumbar colonic nerves (LCN) elicited a clear-cut contraction of the IAS, while rectal motor responses were only occasionally observed. Epidural anaesthesia encompassing the thoraco-lumbar region (EDA), when used to block the sympathetic discharge to the IAS and the rectum, caused a reduction of anal pressure (28 +/- 11%) and an increased rectal tone. The results imply that the human IAS receives a sympathetic excitatory innervation via both the HGN and the LCN. Furthermore, it appears that the HGN convey inhibitory fibres to the IAS. The rectal responses to EDA and sympathetic nerve stimulation also indicate the presence of both excitatory and inhibitory neurones in the sympathetic nerve supply to the rectum in man.

Aged↗
PubMed1991

Fate of the rectum after colectomy and ileostomy for Crohn's colitis.

Eighty-four patients had colectomy with ileostomy and oversewing of the rectum for Crohn's colitis. Seventy-two patients were operated on because of intractable disease, colitis in combination with rectal fistulas, and toxic megacolon. The operative mortality was 6 percent, and neither emergency surgery nor treatment with steroids correlated with operative morbidity. After a median 7.7 years of follow-up, 25 ileorectal anastomoses had been undertaken, 16 of which were successful. Twenty-nine protectomies were performed; the resulting 10-year cumulative risk of proctectomy was 50 percent. While the risk of proctectomy was significantly less among patients with a normal rectum at colectomy compared with patients with proctitis, the initial macroscopic degree of proctitis did not correlate with the risk of subsequent proctectomy. The 5-year cumulative ileal resection rate in 29 patients with a rectum in situ but out of circuit was 29 percent. The possibility of a future ileorectal anastomosis should still be considered in patients with proctocolitis.

Adolescent↗
PubMed1996

Local ischemia causes carcinoma-like changes of the rectum.

PURPOSE: Bioptic specimens of typical cancerous changes in the rectum usually reveal signs of malignancy. Our goal was to describe the clinical feature, histologic findings, and long-term outcome of patients in whom typical findings of carcinoma of the rectum were discovered by endoscopy, but whose histologic data did not confirm the diagnosis of a malignant disease. METHODS: We conducted a retrospective review of eight patients seen in our hospital with a clinical diagnosis of colorectal cancer. RESULTS: All patients had typical macroscopic findings of colorectal cancer. Endoscopic examination was performed because of chronic gastrointestinal symptoms (tenesmus, diarrhea, hematochezia, recurrent rectal prolapses; n = 5), incidental masses detected by rectal palpation (n = 2), or acute rectal bleeding (n = 1). Instead of confirming malignancy, all histologic specimens showed typical signs of intestinal ischemia. In three patients, tumors were removed by endoscopy; the other patients received symptomatic therapy. All patients were followed for an average period of 46 months. In five patients, symptoms disappeared completely. Three patients continued to suffer from intestinal discomfort. In one case, progression of ischemic damage led to subtotal stenosis, which necessitated proctectomy. CONCLUSIONS: Our results indicate that, despite its rarity, "ischemic pseudocarcinoma" is an important differential diagnosis to cancer of the rectum. Prognosis is generally good. Only patients suffering from chronic symptoms may require surgical treatment.

Adult↗
PubMed1999

Anorectal function after anterior resection with side-to-side anastomosis for carcinoma of the rectum.

PURPOSE: The aim of this study is to demonstrate whether anorectal function after anterior resection with side-to-side anastomosis results in better clinical outcomes than end-to-end anastomosis in patients with carcinoma of the upper half of the rectum. METHODS: Anorectal function was studied in two groups of patients who had anterior resection, those with end-to-end anastomosis (Group E; n = 11) and those with side-to-side anastomosis (Group S; n = 11). Eight control subjects who had sigmoid colectomy for carcinoma were also studied. Each patient underwent manometric study and was questioned about clinical bowel symptoms before the operation and 3, 6, and 12 months postoperatively. RESULTS: The median length of residual rectum in both Group S and Group E was 7 cm. No significant difference was observed in maximum anal resting pressure and maximum squeeze pressure between the groups before and after operation. Maximum tolerable volume in Group S was significantly higher than that in Group E and was close to that in the control group at each postoperative interval. Median volumes in Group S were 200 ml (3 months), 220 ml (6 months), and 220 ml (12 months). Median volumes in Group E were 140 ml (3 months), 150 ml (6 months), and 175 ml (12 months). Bowel frequency per 24 hours at three and six months postoperatively was significantly greater in Group E than in Group S or the control group. Median frequency in Group E was four times (3 months) and three times (6 months) per 24 hours. Median frequency in both Group S and the control group was two times (3 months) and two times (6 months) per 24 hours. Postoperative urgency of defecation was not found in Group S, significantly less frequent than in Group E at three months. CONCLUSION: Side-to-side anastomosis may lead to a better clinical outcome than end-to-end anastomosis for carcinoma of the upper half of the rectum in the adaptation phase.

Aged↗
PubMed1994

Decrease in the anorectal pressure gradient after low anterior resection of the rectum. A study using continuous ambulatory manometry.

PURPOSE: Changes in anorectal function after low anterior resection of the rectum (LAR) often lead to symptoms of urgency and frequency of defecation, the anterior resection syndrome. It has been reported that preservation of part of the rectum improves clinical results, but why this should be remains unclear. METHODS: We have carried out continuous ambulatory manometric studies in two groups of patients: 11 patients, a median of 11 (range, 5-96) months after LAR, in whom the median anastomotic level above the anal high-pressure zone was 0 (range, 0-2) cm; 9 patients, a median of 6 (range, 3-12) months after sigmoid colectomy, in whom the rectum remained in situ and who acted as controls. RESULTS: Comparing the LAR group with controls, resting anal pressures were lower, median 68 (range 27-102) cm H2O vs. 95 (45-116) cm H2O (P < 0.05), and neorectal pressures were higher, 25 (0-48) cm H2O vs. 10 (0-10) cm H2O (P < 0.01). Thus the anorectal pressure gradients were less, 34 (0-74) cm H2O vs. 81 (35-113) cm H2O (P < 0.01). Slow-wave activity in the anal sphincter was present in six patients (55 percent) after coloanal anastomosis and eight patients (89 percent) after sigmoid colectomy. Sampling episodes were seen in only two patients (18 percent) after coloanal anastomosis and five patients (56 percent) after sigmoid colectomy. When clinical endpoints were compared (LAR vs. controls), bowel frequency in 24 hours was higher, 5 (3-8) vs. 2 (1-3) (P < 0.01); fecal leakage was more common, affecting seven patients (64 percent) vs. one patient (11 percent) (P < 0.05), and urgency of defecation was also more common. CONCLUSIONS: The inferior clinical results observed after LAR compared with the results after sigmoid colectomy are thus in part because of higher neorectal pressure acting on a weakened sphincter mechanism. These observations lend support to the idea that neorectal capacity should be increased in patients who undergo low anterior resection.

Aged↗
PubMed1978

Precancerous lesions of the colon and rectum.

Fourty-six cases of polyps and polypoid lesions of the colon and rectum were operated at the First Department of Surgery, Gifu University School of Medicine during the last 16 years. Polyps were classified into five groups according to their degree of atypicality and the relationship between polyps and cancer was investigated. The adenomatous polyps were prone to become malignant and it appears that the larger the polyp size, the greater the incidence of severe atypia and the greater the polyps' malignant potentiality. The malignant polyps developed more frequently in the distal colon and rectum than in other parts. Focal and invasive cancers limited to the submucosal layer were found exclusively in the sigmoid colon and rectum.

Adenoma↗
PubMed1988

Relationship between parietal blood flow studies in the left colon and the rectum in dogs. Colonic pressure and blood flow.

An animal model was proposed to clarify the difference in occurrence of enterocolitis in congenital aganglionosis. When gaseous distention of the colon was localized to the rectosigmoid area, enterocolitis never occurred. On the contrary, when it involved the left colon, enterocolitis occurred in 13 of 15 patients. Intestinal blood flow rates were simultaneously measured in the left colon and rectum of six dogs by using labeled microspheres and expressed in function of the intraluminal pressure. Results show that for elevated values of intraluminal pressure, blood flow was significantly lower in the left colon than in the rectum. These results may explain why ischemia and necrosis occurred more frequently in the left colon than in the rectum.

Animals↗
PubMed1985

Sphincter-saving procedure for treatment of diffuse cavernous hemangioma of the rectum and sigmoid colon.

Two cases of diffuse cavernous hemangioma of the rectum and rectosigmoid colon are reported. Sphincter-saving procedures were applied as the surgical treatment for these two patients. The diseased rectum and distal sigmoid colon were resected 3 cm above the pectinate line. The mucosa of the rectal stump was extirpated. All visible residue from the hemangiomatous tissues on the muscular cuff, pararectal space, and pelvic wall were denuded. The normal colon was then pulled down through the rectal cuff and anastomosed with anoderm, and attached to the internal sphincter muscle. Both patients recovered uneventfully. No uncontrollable hemorrhage was encountered during rectal dissection. Both patients had good anal sensation and perfect continence. No complicated sexual or urinary disturbances were found. The sphincter-saving procedure for treatment of diffuse cavernous hemangioma of the rectum should be promoted and given first choice whenever possible.

Adolescent↗
PubMed1985

Disturbances in the defecation mechanism with special reference to intussusception of the rectum (internal procidentia).

Anorectal disorders that disturb normal defecation are described, especially intussusception of the rectum (internal procidentia). A review of 190 patients, half of whom were treated operatively and the other half conservatively, is presented. Diagnostic procedures, symptoms, and indications for operations are evaluated. We believe that intussusception of the rectum is a relatively common cause of difficult emptying of the rectum and, when the correct diagnosis is established, operation presents a fair chance for improvement.

Adult↗
PubMed1998

[Dosimetry methods in determining radiation dosage of the rectum in HDR-brachytherapy of cervix carcinoma].

BACKGROUND: Dosage measurements in brachytherapy of cervix carcinoma are usually obtained with semiconductor dosimeters intrarectally and calculated using approximation methods for additional points, e.g. chosen according to ICRU Report 38. This procedure allows minimizing organ risk dosages and avoiding side effects. This study compares actual dosage measurements with computed approximations. METHODS: In 75 applications the measured actual rectum dosage was analyzed retrospectively. Using graphic approximation methods in conjunction with the localization radiographs the expected dose values at 5 detector points of the intrarectal semiconductor dosimeter and at the ICRU rectal reference point were determined. Prospectively for 11 additional applications the expected dosage for various points within the rectum were computed during therapy planning and additionally for specific reference points corresponding to Fletcher's lymphatic trapezoid and Chassagne's pelvic wall points. RESULTS: The retrospective evaluation showed that 95% of values determined by graphic approximation methods varied by as much as +/- 30% from measured values. Factors causing errors were incorrect assessment of the applicator's spatial positioning, non-orthogonal radiographs, incorrect calibration of the semiconductor probe, movement of applicator and/or probe in the time between radiograph and application. In the prospective group 95% of deviations between measured and calculated values lay within an interval of +/- 40% (Figure 1). Possible sources of error could be similar to those in using the graphic approximation, although the reconstruction of spatial positioning of the applicator is possibly more exact. Doses determined at the ICRU rectal reference point were 5.6 +/- 2.5 Gy in the retrospective analysis and 6.1 +/- 1.6 Gy in the prospective study (Figure 2). The standard deviation of measured values at the specific reference points was +/- 30%. The mean dosage distribution was nearly symmetrical with regard to the body axis, i.e. to the applicator position. Reasons for the relatively large standard deviation are e.g. difficulties in defining the reference points as well as in identifying them on the radiographs, also differences in applicator positioning. CONCLUSIONS: The retrospective analysis led to a larger error than the prospective one. The graphic approximation method should only be utilized when computer-assisted treatment planning is not possible. Conspicuous are the differences between values obtained in computer planning and actual measured values. As these deviations cannot always be explained unequivocally, both computation and measurement should always be conducted in order to obtain an adequate survey of dosage distribution within the rectum. Computer planning offers the additional advantage of determining the dose at various other reference points.

Brachytherapy↗
PubMed2004

"On table" positioning for optimal access for cancer excision in the lower rectum.

Poor visualization and restricted access often make tumor lesions in the lower rectum difficult to excise, particularly in a narrow male pelvis. The aim of this study was therefore to study whether (and if so to what extent) different positions of the patient on the operating table might improve accessibility. Twenty consecutive patients (men and women) undergoing laparotomy with surgery of the lower rectum were studied. The geometric configuration of the pelvis was studied and compared on lateral radiographs obtained at the operating table in each of four positions. Compared with the conventional lithotomy position, "the thighs-flat" position caused significant extension movement of the lumbosacral joint. Augmentation of the lumbar lordosis widened the pelvic view and enabled a more vertical view of the lower rectum (27.5 degrees in lithotomy position, 13.0 degrees in the thighs-flat position). Insertion of a "lumbar pad" contributed further to the augmentation (7 degrees). When compared on radiographic studies, the thighs-flat position is preferable to the conventional lithotomy position in terms of facilitating low rectal surgery by improving both visibility and accessibility to the pelvic cavity.

Adult↗
PubMed2002

Relationship of the fistulas to the rectum and genitourinary tract in mouse fetuses with high anorectal malformations induced by all-trans retinoic acid.

Since high anorectal malformations with fistulae in human embryos and fetuses of successive developmental stages have not been reported, the embryologic relationship between the rectal fistula (RF) and the genitourinary tract (GUT) in high anorectal agenesis (ARA) remains to be elucidated. This study investigates the developmental relationship between the RF and the GUT in male and female fetuses with high ARA using our established model for high ARA with fistula in mice. Pregnant mice received all-trans retinoic acid suspended in corn oil (5 mg/ml) 100 mg/kg i.p. on day 9 of pregnancy. All fetuses were removed from the uterus on a single day from days 12 to 18 of pregnancy. The caudal regions were analyzed histologically with hematoxylin and eosin staining. All fetuses examined had high ARA with fistula. On day 12 of pregnancy, an anomalous communication was seen between the urogenital sinus (UGS) and the rectum. In the affected female fetuses, on day 14 of pregnancy the paramesonephric (müllerian) ducts and müllerian tubercle were located above the rectocloacal fistula (RCF), and on day 18 of pregnancy the uterovaginal canal was located between the cloaca and the RCF. In the male fetuses, on day 14 of pregnancy the junction between the mesonephric (wolffian) duct and the UGS was located away from the junction between the rectum and the UGS. On day 18 of pregnancy the ejaculatory duct was located between the urinary bladder and the rectourethral fistula. The results of our experiment clearly show the embryologic relationship between the RF and the GUT with high ARA. The anomalous communication between the UGS and the rectum may interfere with normal caudal migration along the dorsal wall of the UGS at the junction between the UGS and the mesonephric or paramesonephric duct.

Anal Canal↗
PubMed1998

Serial evaluation of anorectal function following low anterior resection of the rectum.

PURPOSE: This prospective study was performed to serially assess the changes in anorectal function after low anterior resection of the rectum, and to elucidate the mechanisms of functional impairment and the recovery process. MATERIALS AND METHODS: Thirty-two patients undergoing low anterior resection for rectal cancer were evaluated prospectively. Standardized interviews concerning anorectal function and physiologic studies consisting of manometry and balloon proctometry were performed preoperatively, then at 1, 3, and 6 months, and 1 year after the operation. Depending on the length of the residual rectum, patients were divided into two groups: (1) shorter than 4 cm (the short group, n = 18), and (2) longer than or equal to 4 cm (the long group, n = 14). RESULTS: Postoperatively, stool frequency increased and urgency to defecate occurred, which continued until 3-6 months had passed and was more remarkable in the short group. Overall incontinence score increased, which was more remarkable in the short group. Anal resting pressure showed a moderate reduction after 3 months, whereas squeeze pressure did not decrease significantly. Rectoanal inhibitory reflex was postoperatively abolished in almost all patients in the short group, which showed nearly no recovery for 1 year. In the long group, it persisted postoperatively in half the cases, and the reflex returned in a few cases within 1 year. Balloon proctometry revealed overall reduction in rectal capacity and compliance. Although the values tended to recover steadily, they did not reach the preoperative level for 1 year. Urgent volume and maximal tolerable volume remarkably declined, which continued for 1 year and for 6 months, respectively. Rectal compliance also decreased considerably, which continued for 6 months. Most values of rectal capacity tended to be smaller in the short group. CONCLUSION: Impairment of continence after low anterior resection seemed multifactorial, including diminished rectal capacity and compliance, impaired internal anal sphincter tone, and loss of rectoanal inhibitory reflex. Clinical outcome was better and reduction in rectal capacity was less in patients whose rectum remained more than 4 cm. Most of the functional impairments clinically recovered by 6 months postoperation. In the process of clinical recovery of continence, restoration of rectal capacity and compliance and internal anal sphincter tone seemed to contribute a significant degree, while the rectoanal inhibitory reflex did not contribute as much.

Adult↗
PubMed1999

Short-chain fatty acids stimulate mucosal cell proliferation in the closed human rectum after Hartmann's procedure.

Hartmann's procedure in humans results in a closed rectum deprived of its natural short-chain fatty acid source. This induces atrophy of the entire rectal wall. Ki-67 is a monoclonal antibody directed towards proteins in the cell nucleus that are present only during cell proliferation. This study investigated the effects of short-chain fatty acids on mucosal cell proliferation in the human rectum after Hartmann's procedure by means of Ki-67. Eight patients in whom Hartmann's procedure was performed were treated with placebo and then short-chain fatty acids for 14 days. Biopsies specimens were taken from the rectum before and after treatment; these were prepared with Ki-67 and labeling index was determined. The treatment was found significantly to increase proliferative activity in the rectal mucosa (P<0.01); the increase was principally in the middle (P<0.01) and upper crypt (P<0.05) compartments.

Adult↗
PubMed2000

Effects of medium hypertonicity on water permeability in the mammalian rectum: ultrastructural and molecular correlates.

Minute-by-minute net water fluxes (Jw) were measured across the isolated rectal epithelium in rats and rabbits. Five minutes after a serosal (but not mucosal) hypertonic challenge (plus 200 mosmol/l) a significant increase in the basal Jw was recorded in both species [deltaJw, microl min(-1) cm(-2): 0.40+/-0.06 (rats); 0.45+/-0.10 (rabbits)]. At the same time, most epithelial cells shrank markedly while the intercellular spaces were wide open (electron microscopy studies). In freeze-fracture studies multi-strand tight-junction structures (only slightly modified by serosal hypertonicity in rabbits) were observed in control conditions. No structural changes were observed after mucosal hypertonicity (both in rats and rabbits). Immunohistochemical studies showed the expression of aquaporin 3 (AQP3) at the basolateral membrane of epithelial cells in the rat. A first conclusion is that the epithelium of the mammalian rectum is a highly polarized, aquaporin-3-containing, water permeability structure. The Jw increase induced by serosal hypertonicity was sensitive to mercurial agents in both species and no changes in unidirectional [14C]mannitol fluxes (Ps) or transepithelial resistance (RT) were observed during this Jw increase. These observations suggest a transcellular route for the osmotically induced increase in water fluxes. In the rabbit rectum the initial Jw response, associated with serosal hypertonicity, was a transient one. It was followed by a second, slow and HgCl2-sensitive Jw increase (a transient peak in paracellular mannitol permeability was also observed). A second conclusion is that serosal hypertonicity induces an increase in transcellular water permeability in both rat and rabbit rectum.

Animals↗
PubMed2004

Oncological outcomes after total mesorectal excision for cure for cancer of the lower rectum: anterior vs. abdominoperineal resection.

PURPOSE: This study was designed to examine the outcome of cancer of the lower rectum, particularly the rates of local recurrence and survival for tumors located in this area that have been treated by anterior or abdominoperineal resections. METHODS: A prospective, observational, national, cohort study which is part of the Norwegian Rectal Cancer Project. The present cohort includes all patients undergoing total mesorectal excision in 47 hospitals during the period November 1993 to December 1999. A total of 2,136 patients with rectal cancer within 12 cm of the anal verge were analyzed; there were 1,315 (62 percent) anterior resections and 821 (38 percent) abdominoperineal resections. The lower edge of the tumor was located 0 to 5 cm from the anal verge in 791 patients, 6 to 8 cm in 558 patients, and 9 to 12 cm in 787 patients. According to the TNM classification, there were 33 percent Stage I, 35 percent Stage II, and 32 percent Stage III. RESULTS: Univariate analyses: The five-year local recurrence rate was 15 percent in the lower level, 13 percent in the intermediate level, and 9 percent in the upper level (P=0.014). It was 10 percent local recurrence after anterior resection and 15 percent after abdominoperineal resection (P=0.008). The five-year survival rate was 59 percent in the lower level, 62 percent in the intermediate level, and 69 percent in the upper level (P<0.001), respectively, and it was 68 percent in the anterior-resection group and 55 percent in the abdominoperineal-resection group (P<0.001). Multivariate analyses: The level of the tumor influenced the risk of local recurrence (hazard ratio, 1.8; 95 percent confidence interval, 1.1-2.3), but the operative procedure, anterior resection vs. abdominoperineal resection, did not (hazard ratio, 1.2; 95 percent confidence interval, 0.7-1.8). On the contrary, operative procedure influenced survival (hazard ratio, 1.3; 95 percent confidence interval, 1-1.6), but tumor level did not (hazard ratio, 1.1; 95 percent confidence interval, 0.9-1.5). In addition to patient and tumor characteristics (T4 tumors), intraoperative bowel perforation and tumor involvement of the circumferential margin were identified as significant prognostic factors, which were more common in the lower rectum, explaining the inferior prognosis for tumors in this region. CONCLUSIONS: T4 tumors, R1 resections, and/or intraoperative perforation of the tumor or bowel wall are main features of low rectal cancers, causing inferior oncologic outcomes for tumors in this area. If surgery is optimized, preventing intraoperative perforation and involvement of the circumferential resection margin, the prognosis for cancers of the lower rectum seems not to be inherently different from that for tumors at higher levels. In that case, the level of the tumor or the type of resection will not be indicators for selecting patients for radiotherapy.

Abdomen↗