Usefulness of a pediatric colonoscope for routine colonoscopy in women who have undergone hysterectomy

BACKGROUND: Colonoscopy can be difficult in some women who have undergone hysterectomy, which can be associated with a fixed, angulated sigmoid colon caused by postoperative pelvic adhesions. Our goal was to determine whether colonoscopy is easier and more comfortable for women after hysterectomy when performed with a pediatric colonoscope, which is thinner in diameter and more flexible than a standard "adult" colonoscope. METHODS: One hundred women with a history of hysterectomy undergoing outpatient colonoscopy were randomized in unblinded fashion to colonoscopy with a standard colonoscope (CF-100L or CF-Q140L, Olympus) or with a pediatric colonoscope (PCF-100, Olympus). All procedures were performed by a faculty endoscopist and timed. After examination, the endoscopist graded procedure difficulty, and patients were given a questionnaire that assessed their experience. RESULTS: The cecum was intubated more frequently in the pediatric colonoscope group than in the standard colonoscope group (96.1% vs. 71.4%, p < 0.001). Success increased in the standard colonoscope group to 89.8% when the pediatric colonoscope was used to complete the examination. There were no differences in the two groups in terms of mean total procedure times (21.4 minutes vs. 22.6 minutes), mean doses of meperidine administered (57 mg both groups), mean doses of midazolam administered (1.5 mg vs. 1.7 mg), scales of procedure difficulty as graded by the endoscopists, and comfort scales as graded by patients. For the cases in which the cecum was intubated, the mean time to reach the cecum (11.7 minutes for the pediatric colonoscope group vs. 12.7 minutes for the adult) was similar. CONCLUSIONS: The pediatric colonoscope is a reasonable choice for colonoscopy in women who have had a hysterectomy. Alternatively, if the endoscopist elects to start the procedure with a standard colonoscope, it is helpful to have a pediatric colonoscope available for use should a fixed, angulated sigmoid colon be encountered that cannot be easily or safely traversed with the standard colonoscope.     

Colonoscopy: go small for success?

Colonoscopy using standard adult colonoscopes can be difficult in patients with fixed, angulated sigmoid colons. An earlier study from the same center suggested that in women who have had hysterectomy, successful colonoscopy occurred with greater frequency when initiated with a pediatric colonoscope versus an adult colonoscope. This follow-up study was a nonblinded clinical trial comparing the use of a pediatric colonoscope with an adult colonoscope for routine colonoscopy in women with previous hysterectomy. A total of 100 female patients presenting for an outpatient colonoscopy were randomized to use the pediatric (Olympus PCF-100) or adult (Olympus CF-100L or CF-Q140L) colonoscope.
The primary outcome was the comparative rate of cecal intubation. Secondary outcomes included total procedure time, cecal insertion time, sedative administration, procedural difficulty, and patients' experience. Endoscopists encountering difficult insertion had the opportunity to use the alternate scope. The cecum was reached in 49 of 51 (96.1%) women when using the pediatric colonoscope versus 35 of 49 (71.4%) women when using the adult colonoscope. Of the 14 incomplete examinations initiated with an adult colonoscope, the pediatric colonoscope was used 12 times, and the cecum was reached in nine, adjusting the rate of successful colonoscopy to 44 of 49 (89.8%). There was no statistical difference in total procedure time, cecal insertion time, sedative drug dosages, procedural difficulty, or patient comfort using either scope.
When performing routine colonoscopy in women with previous hysterectomy, the authors recommend either starting with a pediatric colonoscope or having one available in the advent of a fixed, angulated sigmoid colon.     

Use of a pediatric colonoscope improves the success of total colonoscopy in selected adult patients

Background: Colonoscopy using a standard adult colonoscope can be difficult or impossible when there is a fixed, angulated sigmoid colon or stricture. It is sometimes possible to traverse such segments using a smaller-diameter, more flexible pediatric colonoscope. Methods: For this prospective study, one endoscopist started 645 consecutive, elective colonoscopies with a standard adult Olympus CF-100L colonoscope (52% women, 48% men). There were 36 examinations (5.6%) in which the adult colonoscope could not be passed through a fixed, angulated sigmoid colon (n = 34) or a sigmoid colonic stricture (n = 2). In such instances (33 women and 3 men), the endoscopist switched to a pediatric colonoscope. Results: The pediatric colonoscope successfully reached the cecum in 21 of the 36 cases (58.3%). The figure was 38.5% for the older Olympus CF-P20L fiberoptic colonoscope (n = 13) and 69.6% for the newer Olympus PCF-100 videocolonoscope (n = 23). Concomitant conditions in the 34 patients in whom the pediatric colonoscope was used because of a fixed, angulated sigmoid included previous pelvic surgery in 22, pelvic radiation therapy in 2, pelvic endometriosis in 3, and two with previous sigmoid diverticulitis. Conclusions: The pediatric colonoscope, and particularly the newer Olympus PCF-100 colonoscope, is very useful in adult patients in whom it is not possible to traverse a fixed, angulated sigmoid colon or stricture using the standard adult colonoscope. This is predominantly a problem of female patients. Previous pelvic surgery may be an important causative factor in this regard. (Gastrointest Endosc 1996;44:675-8.)     

A randomized controlled trial in a training institution comparing a pediatric variable stiffness colonoscope, a pediatric colonoscope, and an adult colonoscope

BACKGROUND: There are few comparative data on the efficacy of different colonoscopes. This study compared the efficacy of a new pediatric variable stiffness colonoscope with that of standard pediatric and adult colonoscopes in the performance of routine colonoscopy. METHODS: Three hundred sixty-three consecutive patients were randomized to undergo colonoscopy with a pediatric variable stiffness (n = 122), pediatric (n = 114), or adult colonoscope (n = 127). Primary outcomes recorded were minutes to the cecum and completeness of the examination. Secondary outcomes included patient tolerance, use of abdominal compression, and endoscopists' assessment of the difficulty of the procedure. RESULTS: Cecal intubation rates were not statistically different between the groups: variable stiffness (94.3%), pediatric (96.5%), and adult (89.8%) (p = 0.099). There was no significant difference in mean insertion time, patient tolerance, use of abdominal compression, or endoscopists' global assessment or examination difficulty between groups. Overall, the initial completion rate of 93% increased to 97% on switching to a different colonoscope. Colonoscopy was unsuccessful more often and was more time consuming in women who had undergone hysterectomy. CONCLUSION: The variable stiffness colonoscope performs well, but does not appear to offer any distinct advantage over standard pediatric or adult colonoscopes for routine colonoscopy. Further study may identify subgroups of patients that benefit from this new technology.     

Is the variable-stiffness paediatric colonoscope more effective than a standard adult colonoscope for outpatient adult colonoscopy?: A randomised controlled trial

BACKGROUND: Trials with variable-stiffness colonoscopes have yielded conflicting results regarding efficacy and patient tolerance. AIM: We compared a variable-stiffness paediatric colonoscope with a standard adult colonoscope. METHODS: Two hundred and forty consecutive adult outpatients presenting for colonoscopy were randomised to either a variable-stiffness paediatric colonoscope or an adult colonoscope. If there was difficulty in performing colonoscopy with the assigned scope, the endoscopist was given the option of switching to the alternative instrument. In the condition of a severely fixed, angulated sigmoid colon, a final 'salvage' (backup) option was that of switching to an even thinner diameter paediatric colonoscope. RESULTS: The initial frequency of total colonoscopy was similar with the variable-stiffness paediatric colonoscope and adult colonoscope (95.8% versus 96.6%, p=1.0). Factoring in scope changes, the final frequency was 98.3% versus 99.2% (p=1.0). There was no statistical difference between the two groups in terms of insertion time, doses of sedative medications, scales of procedure difficulty, or patient satisfaction. CONCLUSIONS: Adult colonoscope and variable-stiffness paediatric colonoscope are both effective instruments for routine colonoscopy. In cases when the use of the initial scope is unsuccessful, switching to the alternative scope may permit passage to the caecum. There are occasional patients with fixed, angulated sigmoid colons in whom use of an even thinner diameter paediatric colonoscope can be helpful.     

A prospective trial of variable stiffness pediatric vs. standard instrument colonoscopy

BACKGROUND: The pediatric variable stiffness colonoscope is believed to have theoretical advantages over the standard colonoscope, however a systematic evaluation of this instrument in routine clinical practice involving adult patients is lacking. METHODS: Consecutive patients (blinded) undergoing colonoscopy in an outpatient endoscopy center by one of 4 experienced colonoscopists had the procedure performed with a standard colonoscope (n=384) or pediatric variable stiffness colonoscope (n=413). Failure to negotiate the sigmoid colon within 10 minutes was regarded as a failure and, if suitable, the patient was crossed over to colonoscopy with the alternative instrument. RESULTS: Median (95% CI) time to the cecum was significantly faster in the pediatric variable stiffness colonoscope group (odds ratio 5.0: 95% CI[4.7,5.3] minutes) compared with the standard colonoscope group (odds ratio 5.5: 95% CI[5.2,5.8] minutes, p=0.01). There were 22 failures overall (2.8%), 14 in the standard colonoscope group (3.6%) and 8 in the pediatric variable stiffness colonoscope group (1.9%; p=0.1). With regard to the 14 failures in the standard colonoscope group, colonoscopy was attempted with the pediatric variable stiffness colonoscope in 13 and completed successfully in 12 (92%). The pediatric variable stiffness colonoscope was superior in cases of severe stenosing diverticular disease; two of 27 examinations with the pediatric variable stiffness colonoscope were rated as failed vs. 12 of 18 with the standard colonoscope (p<0.001). CONCLUSIONS: Intubation time was faster with the pediatric variable stiffness colonoscope, but use of this instrument was not associated with a superior cecal intubation rate compared with the standard colonoscope. However, in patients with severe stenosing diverticular disease, the intubation rate with the pediatric variable stiffness colonoscope was superior.     

Usefulness of a small-caliber, variable-stiffness colonoscope as a backup in patients with difficult or incomplete colonoscopy

OBJECTIVES: Although variable-stiffness colonoscopes have been developed, difficult or incomplete colonoscopies occasionally occur. The aim of this study was to evaluate the usefulness of a small-caliber, variable-stiffness colonoscope (scVSC) as a backup in patients with difficult or incomplete colonoscopies. METHODS: First, we retrospectively reviewed the cecal intubation rate of colonoscopies in which an adult standard colonoscope (AC) was immediately switched to an scVSC in all patients in whom a colonoscopy with an AC was incomplete. Second, 374 consecutive patients were randomized to undergo colonoscopy with a pediatric variable-stiffness colonoscope (PVSC, n = 123), AC (n = 125), or scVSC (n = 126). The scVSC was used by the same endoscopist to reattempt colonoscopy immediately after colonoscopy with a PVSC or an AC had been assessed as difficult or incomplete. The cecal intubation rate and time and the ancillary maneuvers used were evaluated. RESULTS: Fifty-two (2.5%) of the 2,056 attempted colonoscopies with an AC did not reach the cecum. Fifty-one of the 52 patients (98.1%) had complete colonoscopies after the switch from the AC to the scVSC. The initial intubation rate and time were not statistically different among the groups: PVSC, 95% and 6.8 min; AC, 91% and 7.5 min; and scVSC, 98% and 8.2 min. Cecal intubation was achieved in all five patients (100%) and in 10 out of 11 (91%) patients, respectively, after the PVSC or AC was switched to the scVSC. CONCLUSIONS: The completion rate markedly improved after switching from an AC or PVSC to an scVSC in difficult or incomplete colonoscopies, although the scVSC does not appear to offer any distinct advantage over the AC or PVSC for routine colonoscopies.     

Use of a push enteroscope improves ability to perform total colonoscopy in previously unsuccessful attempts at colonoscopy in adult patients

Objective: Total colonoscopy with use of a standard adult colonoscope can be difficult in the presence of a redundant or angulated colon. It is often possible to traverse these areas with the use of a thinner, more flexible endoscope. The objective of this study was to evaluate the efficacy of completing total colonoscopy using a push enteroscope when a standard colonoscope was unsuccessful. Methods: A prospective analysis was performed for 721 consecutive colonoscopies attempted by two gastroenterologists. Those patients in whom complete colonoscopy was unsuccessful using the standard colonoscope (Olympus CF-100L) had attempts to complete colonoscopy using the enteroscope (Olympus SIF-100). The extent of each exam was recorded. Additional pathologic findings discovered by the use of the enteroscope and therapeutic interventions performed were additionally noted. Results: Colonoscopy using an enteroscope was performed in 32 patients with successful total colonoscopy in 22 patients (68.7%). Additional pathology was noted in nine patients who had successful complete colonoscopy using the enteroscope; adenomatous polyp (  n = 5  ), adenocarcinoma (  n = 1  ), bleeding source (  n = 2  ), and extent of colitis (  n = 1  ). Total colonoscopy rate using standard adult colonoscope was 93.2% (630 of 676) when cases with poor bowel preparation (  n = 23  ) and obstructing lesions (  n = 14  ) were excluded. When the results of successful colonoscopies with the enteroscope were included, the overall completion rate of total colonoscopy improved to 96.4% (652 of 676). Conclusion: The use of the enteroscope to help evaluate patients who have had incomplete colonoscopies with the standard colonoscope increases the diagnostic yield of colonic examination.     

Accessing proximal aspects of folds and flexures during colonoscopy: impact of a pediatric colonoscope with a short bending section

OBJECTIVE: Accessing the proximal sides of colorectal folds, flexures, and valves can be difficult endoscopically and can contribute to missed lesions and failed therapeutic procedures. The aim of this study was to determine whether a prototype colonoscope with a short bending section could facilitate accessing difficult to reach areas proximal to folds, flexures, and valves. METHODS: In a nonrandomized study, the prototype colonoscope, a standard pediatric colonoscope, and a standard adult colonoscope were used to attempt retroflexion in the cecum and, if unsuccessful, in the right colon. RESULTS: The prototype colonoscope allowed cecal retroflexion, including clear visualization of the ileocecal valve and the cecal mucosa medial to the valve, in 95% of attempts. A standard pediatric colonoscope was successful in 50% and a standard adult colonoscope in 24.5%. The prototype was more successful than both the standard pediatric (p < 0.001) and the standard adult instrument (p < 0.001). The standard pediatric colonoscope was successful more often than the standard adult colonoscope (p = 0.02). CONCLUSIONS: Using the ability to retroflex in the cecum as a surrogate marker, a prototype pediatric colonoscope with a short bending section seems to facilitate retroflexion and visualization of the proximal aspects of difficult to see regions in the proximal colon.     

Total colonoscopy: is it always possible?

One-thousand three hundred fifty-one consecutive colonoscopies were performed in an office setting without fluoroscopy. Three different models of colonoscopies were utilized; all were manufactured by the Olympus Corporation of America, and included a videoendoscope, a CF-20L immersible OES-type instrument, and an older fiberoptic colonoscope, CFLB-3W. In all colonoscopies, the cecum was reached in 95.9%, even when an obstructing lesion or stenosis was present. Total intubation was performed in 97% of cases with the videoendoscope, 95.5% with the CF-20L, and 95.7% with the CFLB-3W. In a subgroup of 865 colonoscopies, total colonoscopy was performed in 98% of cases when obstructing lesions (carcinoma or stricture) were excluded from analysis. In this subgroup, total colonoscopy could not be performed in 16 patients because of colonic fixation, tortuosity, or for unknown anatomical reasons. Forty-five percent of this subgroup was female, but of the 16 patients in whom total colonoscopy was not possible, 15 were women, 5 of whom had a previous hysterectomy. We conclude that in the absence of any obstructing lesion, an expert can perform complete colonoscopy in 98% of examinations, and in 95% of all patients presenting for colonoscopy. Total colonoscopy may be more difficult in women than men, but a previous hysterectomy does not seem to adversely affect the ability to perform colonoscopy. The type of instrument used for colonoscopy does not impact on the ability to visualize the entire colon.     

Impact of bending section length on insertion and retroflexion properties of pediatric and adult colonoscopes

BACKGROUND: Colonoscopes with short bending sections facilitate retroflexion but their effect on other aspects of colonoscope insertion are unknown. We sought to determine the impact of short bending on cecal insertion, terminal ileal intubation, and proximal colon retroflexion. METHODS: Two studies were performed. In study 1, we randomized 104 adult patients with intact colons to undergo colonoscopy with a standard pediatric colonoscope (Olympus PCF-160), a prototype pediatric colonoscope with short bending in four directions (PCF-AYL), or a prototype pediatric colonoscope with short bending in two directions, and normal bending in two directions (PCF-AY3L). In study 2, we randomized 70 patients with intact colons to undergo colonoscopy with a prototype 170 degrees wide angle colonoscope (CFQ160-WL) with a standard bending section length or to a prototype 170 degrees colonoscope with a short bending section (CFQ160-W2L). RESULTS: In study 1, the cecum was reached in all patients. Using the AYL, the cecal intubation time (4.08 min) was significantly longer when compared to both the PCF-160 (2.62 min; p=0.0001) and the AY3L (3.25 min; p=0.02). The AYL required the application of abdominal pressure (79%) and activation of the variable stiffness device (70%) more frequently when compared to both the PCF-160 (32%; p=0.0001 and 41%; p=0.02, respectively) and the AY3L (34%; p=0.0003 and 41%; p=0.02, respectively). Successful cecal retroflexion was possible less often with the PCF-160 (57%) when compared to either the AYL (94%; p=0.005) or AY3L (91%; p=0.001). The ability to intubate the terminal ileum was similar in all three groups (PCF-160 and AY3L 100%; AYL 94%) as was the time needed to intubate (p=0.73). Depth of ti intubation was deeper for the PCF-160 when compared to the AYL (p=0.0002) or AY3L (p=0.02). There was a trend toward deeper ileal intubation with the AY3L compared to AYL (p=0.09). In study 2, no difference was noted in cecal intubation time (p=0.1) or in frequency of application of abdominal pressure (p=0.28), position change (p=0.15), or activation of the stiffening device (p=0.46). Cecal retroflexion was successful more often when using the W2L when compared to the WL (p=0.00001). CONCLUSION: Short bending sections facilitate proximal colon retroflexion for both pediatric and adult colonoscopes, but can negatively impact cecal insertion and terminal ileal intubation in pediatric colonoscopes. A pediatric colonoscope with short bending in only two directions had good function for both cecal insertion and proximal colon retroflexion.     

Ultrathin colonoscope with a diameter of 9.8 mm for total colonoscopy

BACKGROUND: The pediatric colonoscope is superior to the standard colonoscope in some patients with a fixed, angulated colon. A colonoscope thinner than the pediatric one is thought to outperform even the pediatric colonoscope in such cases. This study was conducted to assess the efficacy of an ultrathin colonoscope, 9.8 mm in diameter, comparing it with pediatric and standard colonoscopes. METHODS: Three types of colonoscopes were used: ultrathin, pediatric, and standard. A total of 287 consecutive patients were assigned to three groups: ultrathin (n=94), pediatric (n=98), and standard (n=95). First assessment was the ratio of cecal intubation and the reasons for unsuccessful colonoscopy. The second was the time to cecal intubation. RESULTS: Cecal intubation rates were not different among three groups (96% in each). The main reasons for failed colonoscopy were looping in the ultrathin group, and angulation or stricture in the pediatric and standard groups. Mean time to the cecum was slightly longer in the ultrathin group (6.5 minutes) than the pediatric group (5.6 minutes) and standard group (6.1 minutes), but there were no significant differences among three groups. CONCLUSION: Colonoscopy with the ultrathin colonoscope was as successful as with the pediatric and standard colonoscopes. The advantage of the ultrathin colonoscope might be notable in cases with stricture or severe angulation.     

Clinical application of a new colonoscope with variable insertion tube rigidity: a pilot study

BACKGROUND: Colonic loop formation can prolong colonoscopy, increase patient discomfort, and preclude complete examination. A colonoscope with variable insertion tube rigidity may facilitate colonoscopy. Our aim was to determine whether the use of a colonoscope with variable insertion tube rigidity reduces insertion time and improves patient acceptance of colonoscopy. METHODS: Fifty patients were randomly assigned to undergo colonoscopy with a conventional colonoscope or a variable rigidity colonoscope (VRC). Patient acceptance, dosage of medication, use of abdominal pressure, and patient repositioning were assessed. Statistical analysis was performed by the 2-sample Wilcoxon rank sum test and an extension of Fisher exact test. RESULTS: The groups were comparable with respect to age, gender, and medications required during colonoscopy. The cecum was reached in all 25 patients who underwent colonoscopy with the VRC, including 1 patient in whom the cecum was not reached at a previous colonoscopy with a conventional instrument. In the conventional colonoscopy group, the cecum was not reached in 4 patients (2 poor preparation, 2 loop formation). There was no significant difference between the 2 groups with respect to insertion time. In the group that underwent colonoscopy with the variable rigidity instrument, less abdominal pressure was required (p = 0.05), and nursing assessment of patient discomfort was more favorable (p = 0.05). There were no complications and no significant differences in the intubation time to cecum or in repositioning, patient acceptance, or patient assessment of abdominal pain. CONCLUSION:The use of a variable rigidity colonoscope reduced the frequency of abdominal pressure but did not affect intubation time to cecum, repositioning, patient acceptance, or patient assessment of abdominal pain.     

Method of colonoscopy in 42 consecutive patients presenting after prior incomplete colonoscopy

OBJECTIVES: Cecal intubation is one of the goals of colonoscopy. We sought to describe the methodology used by a single experienced examiner to perform colonoscopy in a consecutive group of patients with challenging colons. METHODS: Records of 42 consecutive patients with one or more prior unsuccessful attempts at colonoscopy by a gastroenterologist or surgeon and referred for a repeat attempt at colonoscopy were reviewed. RESULTS: Colonoscopy was complete to the cecum in 40 of the 42 patients (95%). An array of methods was employed, including propofol sedation (n = 2), pediatric colonoscope (n = 8), an external straightener (n = 9), external straightener with pediatric colonoscope (n = 2), upper endoscope (n = 8), guidewire exchange (n = 3), and enteroscope with a colon straightener (n = 1) or an enteroscope straightener (n = 1). CONCLUSIONS: A variety of methods and instruments were employed to achieve a high cecal intubation rate during colonoscopy in a group of patients with prior incomplete colonoscopies. Others may find one or more of these methods useful in patients with challenging colons.     

Effect of magnetic endoscope imaging on patient tolerance and sedation requirements during colonoscopy: a randomized controlled trial

BACKGROUND: Pain during colonoscopy is primarily related to mesenteric stretching from looping of the colonoscope insertion tube. Prompt recognition and removal of loops reduces patient discomfort and may lessen sedation requirements. Magnetic endoscope imaging allows real-time visualization of the colonoscope during insertion. The effect of magnetic endoscope imaging on patient pain and sedation requirements was assessed in a prospective randomized controlled trial. METHODS: A total of 122 consecutive patients undergoing routine colonoscopy by a single experienced endoscopist were randomized to have the procedure performed either with the endoscopist viewing the imager display (n = 62), or without the imager view (n = 60). Procedures began with administration of hyoscine-N-butylbromide alone, and sedative medications (midazolam and meperidine) were self-administered by the patient with a patient-controlled analgesia pump. Cardiorespiratory parameters were recorded and patient pain was assessed with a 100-mm visual analogue scale. RESULTS: The number of attempts at straightening the colonoscope was fewer (median 8 [0-66] vs. 15 [0-87], p = 0.0076) and the duration of looping less (median 4.5 min [0-27.3 min] vs. 6.4 min [0-29.4 min]), when the endoscopist was able to see the imager view. The total number of patient demands (by patient-controlled analgesia) for medication (median 1 vs. 2.5) and total doses of midazolam (median 0.44 mg vs. 0.88 mg) and meperidine (median 16.75 mg vs. 32.5 mg) administered did not significantly differ between patients examined with or without the imager. Patient pain scores were also similar. CONCLUSIONS: Magnetic endoscope imaging allows accurate assessment and straightening of loops during colonoscopy, but without a significant reduction in patient requirements for sedative medication or improvement in patient tolerance. However, the dosages of sedation drugs used were small.     

A randomized controlled trial of total colonic decompression after colonoscopy to improve patient comfort

OBJECTIVES: Bloating occurring after colonoscopy may cause significant discomfort in some patients. We sought to determine whether total colonic decompression decreased bloating and improved comfort after colonoscopy. METHODS: Consecutive outpatients undergoing elective colonoscopy were randomized to total colonic decompression or to the control group after completion of the routine colonoscopy. The colonoscope was advanced again to the cecum and the air aspirated during withdrawal in patients randomized to decompression and the procedure was terminated without decompression in control patients. Pain and bloating was assessed in the recovery room and in 24-48 h using a five-point scale. RESULTS: Sixty-five patients were randomized to decompression and 61 were randomized to the control group. The baseline demographic and procedural characteristics were similar between the two groups, but decompression took significantly longer (median, 17 min vs 14 min, p = 0.0002). Seventy-five percent of the decompression group and 80% of the control group denied any pain during colonoscopy. Significantly fewer patients from the decompression group complained of bloating after the procedure (25% vs 59%, p < 0.001) when questioned in the recovery room. However, comparable patients complained of postprocedure bloating when questioned in 24-48 h after the procedure (45% of decompression group vs 47% of control group, p = 0.86). The nurse and the endoscopist were poor at predicting the patient's bloating and significantly overestimated the level of pain. CONCLUSIONS: Total colonic decompression does not significantly reduce bloating after colonoscopy when assessed 24-48 h after the procedure.     

Magnetic imaging of colonoscopy: an audit of looping, accuracy and ancillary maneuvers

BACKGROUND: Colonoscopy is one of the most frequently performed outpatient examinations. However, the procedure is still technically challenging, largely due to unpredictable looping during insertion. The aims of this study were (1) to assess the frequency of loop formation and types of loop during colonoscopy, (2) to determine the accuracy of the endoscopist's assessment of the anatomic location of the endoscope tip and of the presence and type of endoscope loop formation, and (3) to determine the efficacy of abdominal compression and change in patient position in promoting colonoscope advancement. METHODS: Consecutive patients undergoing routine, day-case colonoscopy were studied using real-time, three-dimensional magnetic endoscope imaging. All examinations were performed by expert colonoscopists, blinded to the imager view. The endoscopist estimated the position of the colonoscope tip, assessed when and what type of loop had formed, and the efficacy of ancillary maneuvers such as hand pressure or patient position change. The magnetic imager view of each procedure was recorded and retrospectively analyzed. RESULTS: One hundred complete colonoscopies were performed. Looping occurred in 91% with N-sigmoid (79%) and deep transverse (34%) being most common. Most loops (69%) were incorrectly diagnosed by the endoscopist. Atypical loops were more common in women than men (p = 0.025). The endoscopist's assessment of tip location was correct 85% of the time overall, but 100% in the cecum. Abdominal pressure was less effective (54 of 145 times, 37%) than patient position change (95 of 144 times, 66%) in promoting endoscope tip advancement. CONCLUSIONS: Looping occurs frequently during routine colonoscopy. Although the endoscopist's assessment of tip location is fairly accurate, the majority of colonoscope loops are incorrectly appreciated. Although used frequently, ancillary maneuvers (abdominal compression and patient position change) are effective in only 52% of attempts.     

Colonoscope length and procedure efficiency

OBJECTIVE: We set out to compare the success of colonoscopy using long and intermediate length standard adult instruments. METHODS: An intermediate length (133 cm working length) and long (168 cm) videocolonoscope were used on an alternate patient basis during routine endoscopy lists. Completion rates, times, and the need for external abdominal pressure were documented, as were causes of failed cecal intubation. RESULTS: Among patients with no history of colon resection and with satisfactory bowel preparation, 173 procedures were performed with the intermediate and 167 with the long colonoscope. There was no significant difference in completion rates (96% for both, excluding patients with strictures), completion times (intermediate mean = 7.73 min, long = 8.11 min; p = 0.44), or need for external abdominal pressure. Similarly, no difference was observed for male and female patients analyzed separately. Though there was no significant difference in completion rates for males and females overall (99% vs 95% excluding patients with strictures, p = 0.08), the latter had significantly longer completion times (mean = 8.75 vs 6.76 min, p < 0.001) and were more likely to require external abdominal pressure. Intermediate colonoscope length was responsible for failure to reach the cecum in one patient only (0.6%). CONCLUSIONS: Although the length of the intermediate instrument rarely compromises colonoscopy, it offers no significant advantage over the long scope for routine procedures.     

Small caliber overtube-assisted colonoscopy

AIM： To combine the benefits of a new thin flexible scope with elimination of excessive looping through the use of an overtube. METHODS： Three separate retrospective series. Series 1：25 consecutive male patients undergoing unsedated colonoscopy using the new device at a Veteran＇s hospital in the United States. Series 2：75 male patients undergoing routine colonoscopy using an adult colonoscope, pediatric colonoscope, or the new device. Series 3：35 patients who had incomplete colonoscopies using standard instruments.
RESULTS： Complete colonoscopy was achieved in all 25 patients in the unsedated series with a median cecal intubation time of 6 min and a median maximal pain score of 3 on a 0-10 scale. In the 75 routine cases, there was significantly less pain with the thin scope compared to standard adult and pediatric colonoscopes. Of the 35 patients in the previously incomplete colonoscopy series, 33 were completed with the new system.
CONCLUSION： Small caliber overtube-assisted colonoscopy is less painful than colonoscopy with standard adult and pediatric colonoscopes. Male patients could undergo unsedated colonoscopy with the new system with relatively little pain. The new device is also useful for most patients in whom colonoscopy cannot be completed with standard instruments.     

170 degrees wide-angle colonoscope: effect on efficiency and miss rates

BACKGROUND: Small polyps are routinely missed during colonoscopy even with careful examination. AIM: To determine and compare endoscopic efficiency and polyp miss rate between a prototype 170 degrees wide-angle (WA) colonoscope and a standard (S) colonoscope. METHODS: Two consecutive same-day colonoscopies were performed in 50 patients with intact colons. The patients were randomized to undergo the first colonoscopy with either the prototype WA 170 degrees angle of view colonoscope or an S adult 140 degrees angle of view colonoscope. RESULTS: The mean time for insertion was 2.09 (1.09) min versus 2.53 (1.47) min (p= 0.002) for the WA colonoscope and the S colonoscope, respectively. Similarly, the mean time for examination during withdrawal was shorter with the WA colonoscope (4.98 (0.94) vs 5.74 (1.12) min; p < 0.0001). The mean insertion time for the second examination was shorter than the insertion time for the first examination, irrespective of the colonoscope (p= 0.006). However, the withdrawal times were not significantly different between the first and second examinations (p= 0.11). The miss rate for all polyps with the WA colonoscope (19%) was similar to the miss rate with the S colonoscope (27%; p= 0.19). The miss rates for adenomas with the WA (10/33; 30.3%) and the S scope (15/50; 30%) were similar (p= 0.98). CONCLUSIONS: The use of the WA colonoscope was associated with a reduction in insertion time to the cecum, as well as examination time during withdrawal. No evidence was found that the accuracy of the two colonoscopes differs.