Usefulness of a pediatric colonoscope for colonoscopy in adults

BACKGROUND: There are few published data on how different types of colonoscopes affect success in reaching the cecum and patient comfort. We examined the feasibility of using a pediatric colonoscope for routine colonoscopy in adults and investigated whether there were subgroups of patients in whom use of this instrument was preferable. METHODS: One-hundred fifty adults undergoing outpatient colonoscopy were randomized to colonoscopy with a standard colonoscope (Olympus CF-100L) or with a pediatric colonoscope (Olympus PCF-100). All procedures were performed by a faculty endoscopist and timed by an independent observer. After examinations, the endoscopist graded procedure difficulty and patients were given a questionnaire that assessed their experience. RESULTS: The adult (n = 77) and pediatric (n = 73) colonoscope groups were comparable in all outcomes measured, including success in reaching the cecum (91% vs. 93%, p = 0.61), mean time to reach the cecum (11.4 vs. 9.7 min, p = 0.07), mean total procedure time (21.8 vs. 21.9 min, p = 0.95), mean meperidine dose (55 vs. 52 mg, p = 0.17); median midazolam dose (2.0 mg in both groups, p = 0.10), the endoscopists' perception of procedure difficulty, and patient comfort scales. Of the 7 patients in whom colonoscopy with the adult colonoscope was unsuccessful, the cecum was reached in 4 by switching to a pediatric colonoscope (all women, 3 of whom had prior hysterectomy). In the 5 patients in whom colonoscopy with the pediatric colonoscope was unsuccessful, the cecum was reached in 1 by switching to an adult colonoscope. Including the cases in which the cecum was reached by switching to the alternative colonoscope, the overall frequency of cecal intubation was 143 of 150 (95%). Subgroup analysis disclosed no difference between the 2 groups in outcomes when gender, presence of diverticulosis, and patient size were considered. Colonoscopy with the pediatric colonoscope was more successful than with the adult instrument in reaching the cecum in women with prior hysterectomy (11 of 12 [92%] vs. 15 of 21 [71%]); however, the numbers in each group were relatively small and the difference was not significant (p = 0.22). CONCLUSIONS: The pediatric colonoscope is suitable for routine colonoscopy in adults. It is also useful in patients in whom colonoscopy with the adult colonoscope is unsuccessful in reaching the cecum (particularly in women). Additional study is needed to see if the pediatric colonoscope is actually superior to the adult colonoscopy for routine colonoscopy in women with prior hysterectomy.     

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.     

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.     

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.     

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.     

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.     

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.     

Usefulness of pediatric colonoscopes in adult colonoscopy

Use of small diameter, extraflexible pediatric colonoscopes has proved to be valuable in adult endoscopy practice, not only for passing strictures and stomas but also where either fixation due to diverticular disease or postoperative adhesions, or unavoidably painful looping made passage of adult colonoscopes impossible. In 70 of 78 (92%) of the cases where the adult colonoscope could not be passed through the sigmoid colon by an expert endoscopist, the pediatric colonoscope passed through, often very easily. Fifteen of these patients were considered to have been saved surgery by successful passage. The "failure" rate for all colonoscopy examinations was only 2%; this low failure rate was attributable to the use of pediatric instruments whenever passage through the sigmoid colon proved to be impossible with standard colonoscopes. In our opinion every unit performing frequent colonoscopies should have a pediatric colonoscope available for selected adult patients as well as for use in children.     

A prospective trial of variable stiffness colonoscopes with different tip diameters in unsedated patients

OBJECTIVES: Few data exist comparing the clinical versatility of variable stiffness (VS) colonoscopes with different tip diameters and stiffness ranges. We compared the intubation time and success rate, maneuvering ease, and patient comfort of three colonoscopes: pediatric VS (PVSC), nonmagnifying adult VS (AVSC), and magnifying VS (MVSC).
METHODS: Two hundred sixteen consecutive patients scheduled for routine colonoscopy were randomized to undergo colonoscopy with one of the three different colonoscopes (PVSC N = 72, AVSC N = 72, MVSC N = 72). Outcome measurements included time required for cecal intubation, success rate for cecal intubation, maneuvering ease, and patient comfort.
RESULTS: The overall success rate for cecal intubation was 95.83%. Intubation time was significantly different among the groups (PVSC 12.88 ± 7.11 min, AVSC 9.25 ± 5.16 min, MVSC 9.62 ± 5.55 min; P < 0.01). Intubation time with PVSC required about 3 min more when compared with AVSC or MVSC. Multivariate analyses revealed that colonoscopy with AVSC required 3 min less when compared with PVSC ( P = 0.03). Age greater than 55 yr, waist circumference, prior hysterectomy, and pain experienced by patients were also factors affecting intubation time.
CONCLUSIONS: In this study, a PVSC might not decrease patient discomfort or intubation time. The ideal colonoscope is the AVSC that has a modest diameter and stiffness range and thus is capable of achieving both a short intubation time and an acceptable comfort level. We also should bear in mind that MVSC has an additional function of magnifying observation.     

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.     

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.)     

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.     

The variable stiffness colonoscope: assessment of efficacy by magnetic endoscope imaging

BACKGROUND: Variable-stiffness colonoscopes combine the flexibility of pediatric instruments for negotiation of the sigmoid colon with the ability to stiffen the insertion tube to prevent or control looping after straightening. Previous studies have found wide variation in the efficacy of the stiffening mechanism. Thus, two studies were conducted to assess the potential benefit of the stiffening device and its optimal use. METHODS: In study 1, the effect of routinely stiffening the straightened variable-stiffness colonoscopes in the mid-descending colon was determined in 82 patients. Two insertions were performed (mid-descending colon to cecum) in each patient with and without application of the stiffening device (randomized). The time to negotiate the proximal colon (mid-descending to cecum), time to pass the variable-stiffness colonoscopes across the splenic flexure into the transverse colon, time to pass the right colon, and ancillary maneuvers used were recorded for each insertion. In study 2, consecutive patients, excluding any with previous colonic resection, were examined by using standard adult variable-stiffness colonoscopes. Real-time views of the procedure with magnetic endoscope imaging were recorded for all examinations, but procedures were randomized to be done either with (n = 88), or without (n = 87) the endoscopist viewing the magnetic endoscope imaging display. Whenever stiffening was applied, the anatomic location of the colonoscope tip and stiffness efficacy were recorded. RESULTS: In study 1, time taken to negotiate the proximal colon (p = 0.0041) and time to negotiate the splenic flexure (p = 0.006) were significantly shorter and ancillary maneuvers performed were fewer (p = 0.0014) with the stiffening device activated. In study 2, stiffening was used with similar frequency in patients examined with and without the magnetic endoscope imaging view, most commonly for passing the splenic flexure (71%), but also in the transverse colon (12%), right colon (9%), and sigmoid/descending colon (8%). Stiffening was significantly more effective when used in combination with magnetic endoscope imaging (69% with imager vs. 45% without imager; p = 0.0102). CONCLUSIONS: Overall, the variable-stiffness device used was effective in controlling looping 57% of the time. Activating maximum stiffness appears to be effective once the sigmoid colon has been negotiated and the colonoscope straightened with the tip in the proximal colon, reducing the number of ancillary maneuvers and shortening the insertion time through the proximal colon. Routine magnetic endoscope imaging further enhances the efficacy of the variable-stiffness colonoscopes by helping to identify the optimal time for stiffening.     

A new variable stiffness colonoscope makes colonoscopy easier: a randomised controlled trial

BACKGROUND: Colonoscopy remains technically difficult in 10-20% of procedures due to variable colonic anatomy and fixation. The ability to vary endoscope shaft flexibility may help insertion to the caecum. METHODS: Consecutive patients attending for day case colonoscopy were randomised to examination with either the conventional Olympus CF200HL (200HL) or a new variable stiffness (VS) colonoscope. Intubation time, use of stiffening function, and patient pain scores were compared. RESULTS: Of 100 cases, 43 were performed with the 200HL and 57 with the VS. Four incomplete examinations occurred with the 200HL (two sigmoid fixations, two benign strictures) and two with the VS (one obstructing cancer, one fixed sigmoid). Changing to the paediatric scope was successful in all but one patient from each group (obstructive lesions). Stiff mode was applied 23 times in 18 patients and was effective in 15 of these. Intubation time was quicker with the VS (median 6 minutes 32 seconds) than with the 200HL (median 10 minutes 35 seconds) (p = 0.0005). Pain scores were less with the VS (median 7) than with the 200HL (median 24) (p = 0.0081). CONCLUSIONS: The variable stiffness colonoscope combines paediatric shaft characteristics with the ability to stiffen when needed. This instrument significantly reduces intubation time and patient discomfort. Further comparisons should be made with the newest colonoscopes which are less stiff.     

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.     

Advances in colonic imaging: technical improvements in colonoscopy

Colonoscopy has been available since the early 1970s and has become critical to the diagnosis and management of colorectal disorders. Features of the modern colonoscope and its variants are discussed, including the role of paediatric and variable stiffness colonoscopes for difficult insertion. The place of magnetic endoscope imaging systems and simulators in routine colonoscopy and training are examined. Finally, several recent innovations are used to illustrate how colonoscopy may evolve in the future, including new takes on the current instrument as well as potentially revolutionary pain-free, technically-easy, robotic devices for examination of the bowel.     

Colonoscopic performance in a sedated health screening population: influence of colonoscope type

Background/Aims: Difficult or incomplete colonoscopes occasionally occur due to variable colonic anatomy and fixation. The aim of this study was to determine whether different types of colonoscopes used would affect the colonoscopic performance and sedation practice. Methodology: Consecutive patients attending for health examination were randomized to examination with either the Olympus GIF-Q260 (OS) or Fujinon EC-450 (FS). The cecal intubation rate and time were evaluated. The dose for sedation was also compared. Results: Among 86 subjects, 44 were performed with the OS scope and 42 with the FS. Intubation time was quicker with the FS than OS (3.6±0.3 vs. 4.7±0.4min, p=0.024). The intubation rate was not statistically different between the OS and FS groups (p=ns). The total dose of sedation used was similar between OS and FS groups (p=ns). The intubation time correlated negatively with body weight (r=-0.28, p=0.01). Conclusions: The FS colonoscope appears to provide additional advantage by improving the speed of cecal intubation without compromising the intubation rate or increasing sedation dose, although the two types of colonoscopes are equally efficient in colonoscopic performance.     

Use of a variable-stiffness colonoscope decreases the dose of patient-controlled sedation during colonoscopy: a randomized comparison of 3 colonoscopes

BACKGROUND: The variable-stiffness colonoscope incorporates different degrees of stiffness of the insertion tube, which can be adjusted during the examination. Whether its use can lead to reduced procedure-related pain and sedative use is unknown. OBJECTIVE: Our purpose was to compare the use of 3 types of colonoscope with different shaft stiffnesses in relation to procedure-related pain and sedative consumption. DESIGN: Prospective randomized trial. SETTING: Endoscopy unit of a university-affiliated hospital. PATIENTS: Consecutive patients undergoing ambulatory colonoscopy. INTERVENTIONS: Random assignment was made of patients into 3 groups to receive colonoscopic examinations by one of the 3 types of colonoscope: conventional standard adult size, 1.3-m; 1.6-m; and the new variable-stiffness adult size, full-length (1.6-m) colonoscope. A mixture of propofol and afentanil, delivered by a patient-controlled syringe pump, was used for sedation in all groups. MAIN OUTCOME MEASURES: Outcome measures included dose of patient-controlled sedation consumed, pain score, cecal intubation rate, cecal intubation time, requirement of abdominal pressure and change of patients' positions during colonoscopy, and endoscopists and patients' satisfaction scores according to a visual analog scale. RESULTS: A total of 335 patients were randomized. Patients in group 3 used significantly less propofol (in milligrams per kilograms, mean [SD]) compared with the other 2 groups (group 1: 1.00 [0.75], group 2: 0.93 [0.62], and group 3: 0.75 [0.65]; P = .02; 1-way analysis of variance). The mean (SD) pain score was also lower in group 3. LIMITATIONS: The endoscopists were not blinded. CONCLUSION: The use of the new variable-stiffness adult-size colonoscope significantly reduced procedure-related pain and doses of sedative medications during colonoscopy.     

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.