الفهرس 
Surgical Anatomy of the ColonOnly 14 pages are availabe for public view
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Abstract
Cancer of the colon is the third most common cancer in men and women in the developed world. Radical resection of the tumor-bearing bowel segment allowing sufficient resection margins and removal of regional lymph nodes is the gold standard in surgery for cancer of the colon and rectum. Traditionally, cancers of the colon were removed through large abdominal incisions. The first laparoscopic colon resection was described in 1991 but it has not been as readily adopted as other minimally invasive procedures. Several factors have likely contributed to this delay, including a steep learning curve for the surgeon, the additional time required to perform the operation, and concerns over the oncologic safety of the procedure in malignant disease including high incidence of port-site metastasis. To address these concerns, researchers initiated several randomized trials from the early 1990s comparing the short- and long-term outcomes of patients undergoing minimally invasive and conventional open colorectal resections. Several recent studies have pooled data from the available trials and confirmed equivalent oncologic outcomes and many short-term benefits for laparoscopic colorectal surgery, including less intraoperative blood loss, decreased postoperative pain, improved pulmonary function, faster recovery of gastrointestinal function short and long-term wound benefits had been improved by recent several studies with fewer wound infections, improved wound healing, with less incidence of incisional hernias and post operative abdominal adhesions. Moreover, the studies comparing the costs of laparoscopic and open colorectal surgery suggest that the increase in theatre and equipment costs tend to be balanced by shorter inpatient hospital stay, less need for analgesics and less incidence of wound infection. The genitourinary function of patients can be successfully preserved with good technical efficiency during laparoscopic sigmoidectomy and rectal surgery. Laparoscopic sphincter-preserving total mesorectal excision did not appear to confer any oncologic disadvantage. Theoretically, there is advantage of magnified view and improved visualization of deep pelvic structures. Under the laparoscope the equivalency in terms of length of the specimen, number of lymph nodes harvested, margins or resections, and adherence to oncologic principles has been well established by several authors. Recent studies proved that, when the correct oncologic surgical techniques are combined with expertise in advanced laparoscopic surgery and these adjunctive measures, it is expected that metastatic implants in port sites should occur in less than 1 % of laparoscopic resections for curable colon and rectal cancer. Prospective studies have revealed that laparoscopic resection, compared with open surgery, did not worsen survival or disease control in patients with colorectal cancers. There is a definite learning curve for laparoscopic colorectal surgery and as such, surgical throughput may be reduced at the early stages, however, the potential short-term benefits for patients are clear the long-term oncologic outcome for patients undergoing laparoscopic resection for curable colon and rectal cancer is directly related to the surgeon’s skills and his experience with minimally invasive colorectal surgery. Conversion to open surgery is an accepted part of laparoscopic colorectal surgery. The conversion rate varies from centre to centre and in relation to the surgical team’s experience. There is a higher conversion rate for rectal than colonic cancer, tumor fixity, increased body mass index, and following previous abdominal surgery. The unplanned conversion group had the highest rate of morbidity and mortality. Good preoperative assessment and selection can prevent hazards of unplanned conversion.
Finally, all patients with colorectal cancer were considered suitable for a laparoscopic resection unless they had absolute contraindications such as intolerance of pneumoperitoneum or acutely obstructed cancer with bowel distension, hypovoiemic shock, massive acute bleeding and critical hemodynamic instability intestinal obstruction, bulky tumors, cancer invasive into adjacent organs, pregnancy and diffuse fecal peritonitis should be viewed as a relative contraindication to laparoscopic bowel resection. However, obesity and old age should no longer be regarded as a contraindication to laparoscopic colectomy.