摘要:

A significant proportion of patients with chronic ulcerative colitis will require an operation, particularly if the inflammatory process involves the entire colon and rectum. With the availability of newer surgical alternatives, the indications and timing for surgery of ulcerative colitis are being reevaluated. Growing evidence suggests that both low-grade and high-grade dysplasia are strong predictors of future malignancy. In the past, definitive treatment required total proctocolectomy and permanent ileostomy. In recent years, colectomy with ileal pouch-anal anastomosis has become the treatment of choice for most patients undergoing elective surgery for ulcerative colitis. Controversy has surrounded some technical aspects of the operation, including the necessity for rectal mucosal resection, the type of ileal pouch, and the need for a diverting ileostomy. Preservation of the anal transition zone with ileal pouch-distal rectal anastomosis should be applied with caution and with a proviso that life-time surveillance will be required. A majority of patients with Crohn's disease will also require at least one surgical procedure for this condition within their lifetime. Although controversial, it would appear that conservative principals should be applied to the surgical management of Crohn's disease of the small intestine and colon. Strictureplasty and balloon dilatation are being evaluated for the management of obstructing Crohn's disease. Ultrasound imaging techniques might be useful in preoperative and intraoperative evaluation of Crohn's disease and may help direct the extent of surgical resection. Endoscopic follow-up soon after ileocecal resection has demonstrated a high incidence of recurring inflammation in the preanastomotic area. Patients with Crohn's colitis appear to have a lower recurrence rate, although the optimum operation for their condition has not been clearly established. Most would agree that ileal pouch operations should be avoided in patients with frank Crohn's colitis, but may be applicable to patients with indeterminate colitis.

ISSN:0267-1379    

出版商:OVID    

年代:1993

数据来源: OVID

ISSN:0267-1379    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Nitric oxide has been shown to be important in the organization of peristalsis and the relaxation of the lower esophageal sphincter. A wave of inhibition that travels down the body of the esophagus ahead of the peristaltic contraction has been demonstrated in humans. High-resolution ultrasonography can image muscle layer thickness and may be useful in studying motor disorders. A new classification of esophageal motor disorders offers hope for standardization. Early results of esophageal myotomy by thoracoscopy or laparoscopy appear promising in the treatment of achalasia or diffuse esophageal spasm. Zenker's diverticulum may be caused by prolonged increased intrabolus pressures caused by a physical restriction on flow at the cricopharyngeus.

ISSN:0267-1379    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

The pathogenesis, diagnosis, and optimal therapy of gastroesophageal reflux disease continue to be intensely investigated. A focus is on hiatus hernia as a contributor to sphincter incompetence and poor clearance. Acid is the most important damaging constituent of gastric refluxate, but the importance of alkaline reflux and nonsteroidal drugs continues to be debated. Exciting reports confirm that the human esophagus secretes bicarbonate in significant quantity. Swallowed salivary bicarbonate remains an important factor in the restoration of a neutral esophageal pH. Animal experiments confirm the presence of paracellular barriers to diffusion, and intracellular mechanisms to buffer acid. Epidermal growth factors and their receptors are present in human esophageal biopsies. The methodology and clinical usefulness of ambulatory pH monitoring and manometry in adults and children continue to be debated. The need for long-term treatment of reflux disease is underlined by studies of natural history in adults, which indicate that symptoms rarely resolve spontaneously. Acid inhibition with omeprazole or high-dose H2-receptor antagonists is the most effective medical therapy, and appears to be safe during 5-year, continuous treatment. Nissen fundoplication had advantages over low-dose H2-receptor antagonists in one 2-year study, but the greater effectiveness of modern therapeutic regimens means that further comparisons are required. Economic modeling shows that omeprazole is the most cost-effective medical treatment.

ISSN:0267-1379    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Barret's esophagus develops when metaplastic columnar cells replace esophageal squamous cells that have been damaged by the reflux of noxious gastric material. Epidemiologic evidence suggests that Barret's epithelium usually develops all at once, and does not progress substantially in extent over time, despite ongoing gastroesophageal reflux disease. Barret's esophagus is the single most important risk factor for esophageal adenocarcinoma. Carcinogenesis in Barret's epithelium appears to involve the activation of protooncogenes such as c-erbB2, and the dysfunction of tumor suppressor genes likep53. Activation of growth factor receptors may also contribute to carcinogenesis, and Barret's epithelium has been found to express epidermal growth factor receptor and its ligands. Barret's specialized columnar epithelium, the type most often associated with malignancy, appears to have an expanded proliferative compartment with a high proportion of cells in cycle.

ISSN:0267-1379    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Esophageal lesions occurring in patients with HIV infection have received great attention in current literature. The spectrum of infections has been better defined by two large prospective studies. A double-blind multicenter trial showed that fluconazole is more effective than ketoconazole in the short-term treatment of esophageal candidiasis and therefore should be regarded as the drug of choice for this condition. Controlled trials should confirm the favorable preliminary results obtained with continuous low-dose administration of ketoconazole and fluconazole as prophylaxis for recurrent esophageal candidiasis. The problem of drug-induced esophageal injury has also received great attention, and concomitant aspirin use is now regarded as a potential cause of refractoriness to treatment in patients with peptic esophagitis. “Natural” drugs and “diet pills” have been suspected of being the cause of esophageal problems. Finally, several systemic conditions with associated esophageal involvement have been reviewed.

ISSN:0267-1379    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Established methods of diagnosis and treatment of bleeding esophageal varices continue to be studied with further clarification of acute and chronic management strategies. New endoscopic and radiologic techniques have been introduced that provide additional or alternative approaches. The question of prophylactic variceal therapy remains in the noninvasive arena and elective invasive methods continue to carry a significant morbidity, but there are attempts to define the patient most at risk of bleeding and rebleeding. The next few years should see a rationalization of treatment algorithms as experience is gained with newer modalities used alone or in combination.

ISSN:0267-1379    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Again, much attention was directed at elucidating the tumori-genesis of esophageal cancer at the molecular level. Of the precancerous conditions, columnar metaplasia continues to generate substantial attention worldwide. In particular, attempts to improve the clinical applicability of flow cytometry with objective markers of impending malignancy are quite exciting. Endoscopic ultrasonography was confirmed as the most accurate staging modality of esophageal malignancy, surpassing computed tomography scanning, especially for the less advanced stages. Increasingly, early or superficial cancers of the esophagus are being described. With respect to therapy, a combination of radiotherapy and chemotherapy continues to generate interest. With respect to palliation, the development of expandable stents may well swing the pendulum back in the direction of intubation to the disadvantage of laser photodestruction.

ISSN:0267-1379    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Therapeutic endoscopy has become a well-accepted treatment method for achalasia, benign esophageal strictures, and palliation of malignant dysphagia. For these indications, a variety of complementary or competitive procedures such as bougienage, balloon dilatation, injection therapy, laser treatment, and the implantation of endoprostheses are available. The selection of the different techniques can be increasingly better adapted to the individual clinical situation on the basis of comparative trials. However, the availability of local expertise appears to remain an important factor in therapeutic decision making. For the treatment of benign strictures bougienage and balloon dilatation seem to be comparably effective and safe. The palliation of malignant dysphagia requires expertise in laser treatment, endoscopic intubation, and radiotherapy. The indication of the exclusive or combined application of these methods depends on the condition of the patient, and the type, site, and extension of the esophagogastric tumor. A significant improvement in the treatment of malignant esophageal stenoses and esophagorespiratory fistulas can be expected with the use of covered self-expanding esophageal stents.

ISSN:0267-1379    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Gastroesophageal reflux disease is one of the most challenging diagnostic and therapeutic problems in benign esophageal disease. Symptoms alone are not a reliable guide to the diagnosis of the disease. Of patients thought to have gastroesophageal reflux disease based on symptoms alone, 25% to 30% do not have increased esophageal exposure to gastric juice on 24-hour pH study. The presence and severity of reflux complications,ie, esophagitis, stricture, and Barrett's esophagus, are related to the presence of a mechanically defective sphincter and an increased esophageal exposure to both acid and alkalinity. Antireflux surgery has been shown to be superior to medical therapy in a recent prospective multicenter randomized trial. Optimal surgical results, however, require the selection of the appropriate antireflux procedure. Options include transabdominal and transthoracic Nissen fundoplication, a Belsey partial fundoplication, often in combination with a Collis gastroplasty as an esophageal lengthening procedure, or rarely an esophageal resection and reconstruction. Twenty-four hour ambulatory manometry improves the diagnostic sensitivity in esophageal motility disorders. Excellent results are obtained with surgical myotomy for achalasia, most recently performed with video-assisted endosurgical techniques. A long esophageal myotomy is a valid treatment alternative in select patients with diffuse esophageal spasm. Technical aspects of esophageal surgery continue to challenge clinicians. Despite difficulties in demonstrating objective benefit, transhiatal esophagectomy has gained widespread acceptance as an alternative to the traditional combined laparotomy and right thoracotomy approach, particularly in the setting of benign esophageal disease and in the palliation of esophageal cancer. Respiratory complications are the most troublesome problems postoperatively. Antireflux surgery may also be superior to medical therapy in preventing complications of Barrett's esophagus, including the development of dysplasia and carcinoma. Endoscopic surveillance of Barrett's esophagus allows early detection of adenocarcinoma and may decrease the mortality rate for esophageal cancer in these patients. Increasing evidence suggests that survival of patients undergoing en bloc esophagogastrectomy for carcinoma of the lower esophagus is improved when compared with standard esophagectomy. Adjuvant radiotherapy alone has now been shown conclusively to be of no benefit for patients with carcinoma of the esophagus.

ISSN:0267-1379    

出版商:OVID    

年代:1993

数据来源: OVID