Colon Tumors and Colonoscopy

Abstract

Sedation and PreparationBowel preparation is one of the main reasons for the low acceptance of colonoscopy. Up to 20 % of colonoscopies are repeated earlier than necessary, due to poor bowel preparation [1]. In a meta-analysis, 11 randomized controlled trials comparing sodium phospate (NaP) and polyethylene glycol (PEG) were pooled, including a total of 861 patients. NaP and PEG were rated as tolerable by 84.5 % and 67.6 % of the patients, and the quality of preparation was good in 82.3 % vs. 74.9 %. The authors therefore recommend NaP [2], confirming the findings of a meta-analysis published 2 years ago [3]. An even better alternative might be a recently developed purgative tablet, which showed excellent acceptance and good preparation in an initial study [4]. The fasting hydrogen breath test may allow identification of some patients with bad preparation [5 ± 7], but it is doubtful whether this will become a standard method prior to colonoscopy.Sedation is the other major factor in patient satisfaction and acceptance of colonoscopy. Propofol administered by a gastroenterologist, instead of midazolam/meperidine, is safe and improves patient satisfaction [8,9]. In the study by Kulling et al. [8], it was found that patient-controlled sedation using propofol and alfentanil resulted in the highest level of patient satisfaction. In both studies, recovery was faster than with midazolam. Technique of ColonoscopyIn two studies, virtual endoscopy simulation using the GIMentor was tested as a training tool for beginners in endoscopy. Although the system has a limited range of colonoscopies, a training effect was demonstrated [10,11]. These simulators will become more sophisticated in the near future, and it can be expected that beginners will start their training with the simulator and not with patients.Comparative studies with variable-stiffness endoscopes and standard endoscopes were again reported from the Mayo Clinic and from Portland, now with larger patient groups. Comparison of adult variable-stiffness endoscopes with pediatric or adult standard colonoscopes showed no differences with regard to insertion time, patient discomfort, sedation, compression, changing of patient position, or intubation of the terminal ileum in 363 patients [12]. The second study, including 245 patients and comparing standard adult colonoscopes and variable-stiffness pediatric or adult colonoscopes, found that the adult variable-stiffness colonoscope is superior with regard to compression and patient positioning. Again, no differences were found for insertion time or the degree of patient acceptance [13]. The initial enthusiasm for variable-stiffness colonoscopes has therefore not been confirmed.A study using the magnetic endoscope imaging (MEI) system at St. Marks Hospital in London, where most of the development of the system has been carried out, confirms previously published results. The authors found a small difference in the pain score when MEI was used, and no difference in analgesia or sedation [14]. It seems that the benefit of MEI...

Early Diagnosis and Prevention of Sporadic Colorectal Cancer1

“…Truly depressed lesions are rare (2.3 % in the Akita Red Cross Hospital series) but the rate of extension to the submucosa is as high as 31 %. This characterization received further confirmation from many Japanese series presented at the Digestive Diseases Week (DDW) 2001 in Atlanta [51]. It is concluded that the endoscopic detection of so-called ªflatº lesions should rather focus on depressed small lesions; this is why a highresolution endoscope is required.…”

“…The pattern in the vertical surface corresponds to the image seen by the pathologist by 7 % and 10 %, respectively. Incidence rates of colon cancer further declined between 1990 and 1996: by 2.7 % and 1.7 % per year in males and females, respectively [51].…”