Effect of real-time magnetic endoscope imaging on the teaching and acquisition of colonoscopy skills: results from a single trainee.

BACKGROUND AND STUDY AIMS: Most trainees have little concept of the loops that occur during colonoscopy, and have difficulty in appreciating the combination of withdrawal and torquing manoeuvres that are essential to achieving complete colonoscopy. Real-time magnetic endoscope imaging (MEI) allows visualization of shaft looping, and so makes intuitive the manoeuvres necessary to straighten the colonoscope shaft. PATIENTS AND METHODS: Consecutive routine colonoscopies were performed by a single trainee (with previous experience of 15 colonoscopies). Procedures were randomly assigned to be carried out either with the trainee viewing the MEI display, or without the MEI view, which was recorded throughout all examinations. RESULTS: In total, 71 procedures were performed. To assess the trend for learning, procedures were analysed in blocks of 24 consecutive examinations (periods 1 to 3). In the first 24 procedures (period 1), the number of attempts at straightening the colonoscope and duration of looping were significantly less, and the intubation time was shorter, for examinations performed with the MEI view. In periods 2 to 3, there was a continued trend towards improved performance, but without a significant difference between procedures performed with or without MEI. CONCLUSIONS: During training, real-time colonoscope imaging using MEI appears to enhance the endoscopist's appreciation of looping and improves the learning of the manoeuvres required to straighten the colonoscope shaft. A prospective, multicentre study assessing a larger number of trainees is needed to clarify these findings.

Patient pain during colonoscopy: an analysis using real-time magnetic endoscope imaging.

BACKGROUND AND STUDY AIMS: Colonoscopy is generally perceived as being a painful procedure. Contributory factors are: stretching of the colonic wall and mesenteric attachments from looping of the instrument shaft, overinsufflation, the degree of torque or force applied to the colonoscope shaft, and patient pain threshold. The aim of this study was to determine the frequency of pain episodes experienced during diagnostic colonoscopy and the corresponding colonoscope configuration, utilizing real-time magnetic endoscope imaging (MEI). PATIENTS AND METHODS: Consecutive outpatients undergoing colonoscopy were studied. Patients with previous colonic resections were excluded. Procedures were commenced with antispasmodics only, and patient sedation was self-administered whenever significant discomfort was experienced, using a patient-controlled analgesia (PCA) syringe pump. All "demands" were correlated with the MEI record, which was subsequently analysed. RESULTS: A total of 650 demands were recorded in 102 patients. Seventy-seven percent of all demands occurred with the colonoscope tip in the sigmoid colon, 7 % in the descending colon, 6 % at the splenic flexure, 5 % in the transverse colon, and 4 % in the proximal colon. Ninety percent of all pain episodes coincided with either looping (79 %) or straightening of the colonoscope shaft (11 %); presumed overinsufflation being an infrequent cause of pain (9 %). Of the loops encountered during colonoscopy, the N-sigmoid spiral loop was associated with the majority of pain episodes (56 %). Looping was both more frequent ( P = 0.0002) and less well tolerated in women than in men ( P = 0.0140). CONCLUSIONS: This study is the first to document pain at colonoscopy accurately. Looping, particularly in the variable anatomy of the sigmoid colon, is the major cause of pain, especially in women. Use of MEI may improve pain control by facilitating the straightening of loops within the sigmoid colon, and by enabling the endoscopist to target patient analgesia.

Effect of magnetic endoscope imaging on colonoscopy performance: a randomised controlled trial.

BACKGROUND: Colonoscopy can be technically challenging because of unpredictable colonoscope looping. Without imaging, straightening the colonoscope is sometimes difficult since the endoscopist has to guess where the tip is. Magnetic endoscope imaging (MEI), a new non-radiographical technique for picturing the colonoscope shaft in real time, could facilitate loop straightening and thus improve performance. METHODS: We assessed trainees and endoscopists with much experience of routine outpatient colonoscopy. In group 1, trainees examined 113 consecutive patients. MEI views were recorded in all examinations, but procedures were randomised to be done by two trainees, either with the endoscopist and endoscopy assistants viewing the imager display (n=58), or without the imager view (n=55). In group 2, two skilled endoscopists were randomised (as with group 1) to undertake consecutive examinations (n=183) either with (n=92) or without (n=91) the MEI view. MEI views of all procedures were analysed retrospectively. FINDINGS: In both groups, intubation times were shorter (median 11.8 min [4.3-31.5] vs 15.3 min [4-67] [group 1]; 8.0 min [2.6-40.8] vs 9.3 min [2.5-52.6] [group 2]) and number of attempts at straightening the colonoscope fewer (median 5 [0-20] vs 12 [0-57] [group 1]; 7 [0-55] vs 10 [0-80] [group 2]), when the endoscopist was able to see the imager view. In group 1, colonoscopy completion rates were also higher (100% [58] vs 89% [49]) and duration of looping was reduced (median 3 min [0-18.8] vs 5.4 min [0-44.5]) when the imager could be seen. Abdominal hand pressure was more effective when the endoscopist and endoscopy assistant could see the imager view. INTERPRETATION: MEI significantly improves performance of colonoscopy, particularly when used by trainees, or by experts in technically difficult cases; loops were straightened or controlled effectively, resulting in quick intubation times and high completion rates.