ISSN:0267-1379    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

During the past year, advancements in understanding the biology and natural history of colorectal neoplasia have been incremental rather than revolutionary. In particular, research has resulted in greater insight into the genetics of familial colon cancer and the chemopreventative effects of aspirin and similar drugs. The development of new technologies such as computed tomographic colography and polymerase chain reaction based testing promises to improve accuracy and reduce the costs of colorectal cancer screening.

ISSN:0267-1379    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Surgery alone is insufficient treatment for most patients with mobile rectal cancers and high-risk factors of tumor extension beyond the rectal wall, node involvement, or both in conjunction. Although single modality adjuvant treatment with pre- or postoperative irradiation can reduce the rate of local relapse, a statistically significant impact on survival has not been achieved. Combined modality postoperative chemoirradiation has resulted in both improved disease control (local and distant) and improved survival (disease free and overall). Randomized trials are underway in high-risk patients to determine the most optimal combinations of postoperative chemoirradiation and to compare preoperative versus postoperative chemoirradiation. For patients with locally advanced primary cancers that are unresectable for cure or locally recurrent cancers, standard therapy with surgery, external irradiation, and chemotherapy is often unsuccessful. When intraoperative electron irradiation is combined with standard treatment, encouraging trends are seen with regard to improvements in local control and survival in separate analyses from the Mayo Clinic and the Massachusesetts General Hospital. More standard use of systemic therapy is needed as a component of treatment, however, in view of high rates of systemic failure in spite of the locally aggressive treatment regimens.

ISSN:0267-1379    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0267-1379    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Gastrointestinal disease is a common manifestation of AIDS. Improved diagnostic techniques have revealed a bewildering range of enteric pathogens whose natural history may be altered in the setting of HIV infection. Effective therapy is still needed for many of these pathogens. Mucosal HIV infection has been demonstrated, but its precise role in HIV pathogenesis remains poorly defined. The abundance of mucosal-associated lymphoid tissue in the gastrointestinal tract suggests that the intestinal mucosa may be a major reservoir of HIV infection. The purpose of this chapter is to review recent developments concerning the pathology, diagnosis, and clinical management of HIV-associated intestinal disease.

ISSN:0267-1379    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Fecal incontinence is a socially disabling disease capable of affecting patients of all ages. A number of different causes can produce this disorder, and patients should be evaluated with anorectal manometry, sphincter ultrasound, and neurophysiologic testing in order to determine if there is an underlying muscular or neurologic cause. Nonsurgical therapy,ie, biofeedback is aimed at improving patient awareness of stool or gas within the rectum, eliciting a prompt sphincter contraction in response, and prolonging the duration of this contraction. Before embarking on reconstructive procedures, one must determine the severity of the incontinence and its impact on lifestyle. A marginally symptomatic patient should be treated with nonsurgical means. Surgical correction may consist of overlapping sphincteroplasty, plication of the sphincter and pelvic floor, nonsphincteric muscle transposition, and artificial sphincter implantation. Treatment should be individualized based on the underlying cause and the degree of impairment.

ISSN:0267-1379    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Constipation has been considered a mixture of three pathogenetic phenomena: slow transit, pelvic floor disorders with outflow obstruction, and irritable bowel syndrome. Recently, nitric oxide has been implicated in slow-transit constipation (and other dilated states). Pelvic floor disorders remain poorly understood owing to limitations in diagnosis and a lack of controlled studies of biofeedback treatment. Irritable bowel syndrome is very common in patients with constipation, and there is now a standardized distention test for diagnosis. Children with constipation and encopresis have afferent nerve abnormalities that may contribute to their problems; they do not appear to benefit from biofeedback for sphincter reeducation. Prokinetic drugs have limited benefit, and subtotal colectomy is a useful last resort for selected severely constipated patients.

ISSN:0267-1379    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Ileal pouchanal anastomosis (IPAA) has emerged as the procedure of choice for patients with ulcerative colitis and most patients with familial adenomatous polyposis. Patients over 60 appear to tolerate IPAA well and have functional results comparable to those achieved in younger patients. The distribution of disease in the colon does not appear to affect outcomes after IPAA. For most patients with familial adenomatous polyposis, IPAA is safe and provides functional results comparable to those achieved with ileorectostomy. The double-stapled IPAA technique now appears to be safe and to provide better functional results in terms of incontinence than the hand-sewn technique. Variations of IPAA technique, including anorectal eversion and anal transition zone resection, are discussed. A large series of IPAA patients confirms the safety and efficacy of IPAA. Pouch failure appears to be primarily the result of uncontrolled fistula and poor function. Nonspecific inflammation of the pouch (pouchitis) is the most frequent long-term complication of abdominal colectomy with ileal pouch-anal anastomosis for ulcerative colitis. The 10-year cumulative risk of pouchitis in patients with ulcerative colitis with and without associated primary sclerosing cholangitis is 46% and 79%, respectively. Smoking protects against pouchitis. The preoperative extent of ulcerative colitis does not predict pouchitis. In contrast to previous reports, recent studies show no association between pouchitis and perinuclear antineutrophil cytoplasmic antibodies. Similar to patients with ulcerative colitis, patients with pouchitis have increased pouch mucosal concentrations of leukotriene B4and cytokines, increased serum concentrations of adhesion molecules, and increased intestinal permeability. Fecal concentrations of bile acids and bacteria do not predict pouchitis. Most patients with pouchitis will respond to metronidazole or ciprofloxacin. Dysplasia occurred in 3% of 87 patients undergoing surveillance endoscopy of the ileoanal pouch after a mean of 6 years of follow-up.

ISSN:0267-1379    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Although laparoscopic applications in colorectal surgery are still evolving, demonstrated benefits, including decreased postoperative pain, length of ileus, and hospital stay, encourage patient and physician enthusiam for this new approach. The cost of the procedure is comparable to that of open surgery, and cost benefits should be realized as conversion rates improve. The technique is feasible, and surgeons are cautioned to be aware of their limitations, as they are learning the procedure, in order to minimize complications and conversion rates. Questions remain, particularly regarding recurrence and survival outcomes with colorectal carcinoma. Patients undergoing laparoscopic colectomy for carcinoma should be enrolled in prospective randomized trials.

ISSN:0267-1379    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Endorectal ultrasound is integral to preoperative staging of rectal cancer in order to select patients for appropriate management options such as preoperative chemoradiation for locally advanced disease or local therapy for early confined lesions. Accuracy of endorectal ultrasound for determining depth of wall invasion ranges from 81% to 94%, with over-staging in 0% to 12% and understaging in 1% to 9% of cases. Accuracy of endoluminal ultrasound for detection of lymph node metastasis ranges from 58% to 80%. Early detection of recurrent cancer using endoluminal ultrasound may allow for potential salvage reoperation. Endoanal ultrasound provides excellent imaging of the anal canal for diagnosis and management of fecal incontinence and perianal sepsis. Ultrasound imaging can confirm suspected injury to the anal sphincter and may identify occult postobstetric injury. Preoperative endoanal ultrasound mapping of complex perianal abscesses and fistulas provides for minimization of exploration and sphincter injury while assuring complete drainage of sepsis.

ISSN:0267-1379    

出版商:OVID    

年代:1997

数据来源: OVID