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

Use of an abdominal binder in colonoscopies performed by trainees in gastrointestinal endoscopy: a randomized, double-blind, sham-controlled trial

BACKGROUND

Colonoscopy is a widely used diagnostic and therapeutic tool for colonic diseases and serves as the preferred screening method for colorectal cancer (CRC). A common difficulty during colonoscopy is the looping of the colon, which can result in patient discomfort, prolonged cecal intubation time (CIT), and the need for auxiliary maneuvers. This study aimed to evaluate the efficacy and safety of using an abdominal binder during colonoscopy performed by trainees.

METHODS

This randomized, double-blind, sham-controlled trial was conducted at a tertiary center. Participants were outpatients aged 20-80 years undergoing elective colonoscopy. They were randomly assigned to either the abdominal binder (AB) group or the sham binder (SB) group. The primary outcome measured was cecal intubation time. Secondary outcomes included the need for manual abdominal compression and postural adjustments during the procedure.

RESULTS

A total of 211 participants were enrolled in the study. The median CIT was significantly shorter in the AB group compared to the SB group (728 s vs. 774 s, p = 0.008). Additionally, the AB group demonstrated a significantly reduced need for manual abdominal compression (p ≤ 0.001) and postural adjustments (p = 0.01). The requirement for abdominal compression decreased by 40% (95% CI 27.7-52.9%), while the need for postural changes was reduced by 9.4% (95% CI 1.9-88.7%).

CONCLUSION

The use of an abdominal binder during colonoscopy performed by trainees significantly reduced cecal intubation time and minimized the need for ancillary maneuvers, such as manual abdominal compression and postural adjustments.

THE USE OF ABDOMINAL CORSETS ON COLONOSCOPY: A PROSPECTIVE RANDOMISED CONTROLLED TRIAL

BACKGROUND

Colonoscopy is a widely used endoscopic procedure to investigate diseases of the colon and rectum. Colonoscopy procedure has difficulties for the patient and endoscopist.

AIMS

To investigate whether the use of an abdominal corset can make the colonoscopy procedure easier and faster.

METHODS

This is a prospective randomised controlled study. Patients over 18 years of age who underwent elective colonoscopy in our clinic were evaluated. Patients were divided into two groups according to the use of the corset. Variables were compared between the groups.

RESULTS

A total of 204 patients were included in the study. Corsets were used in 97 patients and not used in 107 patients. The need for manual compression was found to be decreased in the corset use group. There was no effect of corset use on cecal intubation time in the general population. It was found that cecal intubation time decreased with corset use in patients with body mass index - BMI<30 and male gender.

CONCLUSIONS

The need for manual compression can be reduced by the use of an abdominal corset during colonoscopy. The use of an abdominal corset may make the colonoscopy procedure faster and easier for the endoscopist and the patient.

Water-assisted colonoscopy in inflammatory bowel diseases: From technical implications to diagnostic and therapeutic potentials

Water-assisted colonoscopy (WAC) application in inflammatory bowel diseases (IBD) endoscopy offers significant technical opportunities. Traditional gas-aided insufflation colonoscopy increases patient discomfort, presenting challenges in the frequent and detailed mucosal assessments required for IBD endoscopy. WAC techniques, including water immersion and exchange, provide superior patient comfort and enhanced endoscopic visualisation. WAC effectively reduces procedural pain, enhances bowel cleanliness, and increases adenoma detection rates, which is crucial for colorectal cancer screening and disease-related evaluations in IBD patients. Additionally, underwater techniques facilitate basic and advanced endoscopic resections, such as polypectomy and endoscopic mucosal and submucosal resections, often required for resecting IBD-associated neoplasia.

Painless colonoscopy: fact or fiction?

Although colonoscopy is a routinely performed procedure, it is not devoid of challenges, such as the potential for perforation and considerable patient discomfort, leading to patients postponing the procedure with several healthcare risks. This review delves into preprocedural and procedural solutions, and emerging technologies aimed at addressing the drawbacks of colonoscopies. Insufflation and sedation techniques, together with various other methods, have been explored to increase patient satisfaction, and thereby, the quality of endoscopy. Recent advances in this field include the prevention of loop formation, encompassing the use of variable-stiffness endoscopes, computer-guided scopes, magnetic endoscopic imaging, robotics, and capsule endoscopy. An autonomous endoscope that relies on self-propulsion to completely avoid looping is a potentially groundbreaking technology for the next generation of endoscopes. Nevertheless, critical techniques need to be refined to ensure the development of effective and efficient endoscopes.

Efficacy of ScopeGuide-Assisted Training in Enhancing Colonoscopy Competence and Reducing Patient Discomfort

OBJECTIVE

In this study, we aimed to evaluate the efficacy of the Magnetic Scope Guide Assist (ScopeGuide) in enhancing the procedural competence of endoscopists and reducing patient discomfort during colonoscopy.

METHODS

This was a retrospective study with 88 trainee participants. The study participants were trained on patients who underwent colonoscopy without anesthesia. Both ScopeGuide-assisted training and conventional training (without ScopeGuide) were utilized for colonoscopy instruction. The outcomes of training were compared, with a particular emphasis on the competency of looping resolution.

RESULTS

ScopeGuide-assisted training was superior to conventional training in multiple aspects, including looping resolution ( Z =-3.681, P <0.001), pain scores ( Z =-4.211, P <0.001), time to reach the cecum ( Z =-4.06, P <0.001), willingness to undergo repeat colonoscopy ( Z =-4.748, P <0.001), competence of positional changes ( Z =-4.079, P <0.001), and the effectiveness of assisted compression ( Z =-3.001, P =0.003). Further stratified analysis revealed that the ScopeGuide-assisted training mode was more beneficial for junior endoscopists ( P <0.05 in all parameters) but not for intermediate endoscopists ( P >0.05) and partially beneficial for senior endoscopists ( P <0.05 for all parameters except looping resolution).

CONCLUSION

ScopeGuide-assisted training can significantly facilitate endoscopists in resolving loops and reducing patient pain, thereby enhancing their colonoscopy abilities.

Does Manual Abdominal Pressure During Colonoscopy Put Endoscopy Staff and Patients at Risk? Experiences of Endoscopy Nurses and Technicians

Endoscopy staff suffer work-related musculoskeletal disorders at a rate greater than or comparable to nurses and technicians in other subspecialities, which may be attributable to the widespread use of manual pressure and repositioning during colonoscopy. In addition to negatively impacting staff health and job performance, colonoscopy-related musculoskeletal disorder injuries may also signal potential risks to patient safety. To assess the prevalence of staff injury and perceived patient harm relating to the use of manual pressure and repositioning techniques during colonoscopy, 185 attendees of a recent national meeting of the Society of Gastroenterology Nurses and Associates were asked to recall experiencing injuries to themselves or observing injuries to other staff or patients during colonoscopy. A majority of respondents (84.9%, n = 157) reported either experiencing or observing staff injury, whereas 25.9% ( n = 48) reported observing patient complications. Among respondents who perform manual repositioning and apply manual pressure during colonoscopy (57.3%, n = 106), 85.8% ( n = 91) reported experiencing musculoskeletal disorders from performing these tasks; 81.1% ( n = 150) reported no awareness of colonoscopy-specific ergonomics policies at their facility. Results highlight the relationship between the physical job requirements of endoscopy nurses and technicians, staff musculoskeletal disorders, and patient complications, and suggest that implementation of staff safety protocols may benefit patients as well as endoscopy staff.

Patient Factors Affect Ergonomic Strain of Endoscopists During Colonoscopy

INTRODUCTION

Endoscopic procedures place a great deal of muscular strain on providers, especially over the span of their careers. In this study we quantitatively analyzed the effects of patient factors such as age, body mass index, and sex on the ergonomics of endoscopists performing colonoscopies.

METHODS

Surface electromyography (sEMG) was used to measure ergonomic strain of physicians while performing colonoscopies in several key muscle groups. The percent of the maximum voluntary contraction (%MVC) was used as a measure of muscular strain. Data was then analyzed based on the patient characteristics above.

RESULTS

Endoscopists performing colonoscopies on female patients (n = 47) experienced significantly higher ergonomic strain in their right trapezius and right posterior forearm muscle groups when compared to colonoscopies performed on males (n = 35) (%MVC R-trapezius: Male: 8.2; Female: 8.9; p = 0.048); (%MVC R-posterior forearm: Male: 10.4; Female: 11.6; p = 0.0006). Operators experienced greater strain in the same muscle groups when performing colonoscopies on patients with BMI ≤ 25 (n = 25) when compared to patients with BMI > 25 (n = 57) (%MVC R-trapezius: BMI < 25: 9.7; BMI ≥ 25: 8.2; p = 0.0002); (%MVC R-posterior forearm: BMI < 25: 11.9; BMI ≥ 25: 10.8; p = 0.0001).

CONCLUSION

Physicians experienced greater ergonomic strain when performing colonoscopies on female patients and on patients with a BMI < 25. We believe that these factors potentially impact the tortuosity of the colon and therefore influence the difficulty of navigating the endoscope. These results may aid physicians in gauging the anticipated difficulty of colonoscopies based on patient factors. Increased awareness of their posturing and ergonomics during challenging cases will alleviate musculoskeletal injuries in the long run.

Impact of looping on premalignant polyp detection during colonoscopy

BACKGROUND

The presence of premalignant polyps on colonoscopy is an indicator of metachronous colorectal cancer. Looping during colonoscopy is associated with old age, female sex, and colonoscopy insertion time. However, the clinical significance of looping is not fully understood. We aimed to clarify the effect of looping on colorectal premalignant polyp detection.

AIM

To assess the effects of looping on premalignant polyp detection using logistic regression analyses.

METHODS

We retrospectively investigated patients who underwent colonoscopy at Toyoshima Endoscopy Clinic between May, 2017 and October, 2020. From the clinic's endoscopy database, we extracted data on patient age, sex, endoscopist-assessed looping, colonoscopy duration, endoscopist experience, detection rate, and number of premalignant polyps.

RESULTS

We assessed 12259 patients (mean age, 53.6 years; men, 50.7%). Looping occurred in 54.3% of the patients. Mild and severe looping were noted in 4399 and 2253 patients, respectively. The detection rates of adenomas, advanced adenomas, high-risk adenomas, clinically significant serrated polyps (CSSPs), and sessile serrated lesions (SSLs) were 44.7%, 2.0%, 9.9%, 8.9% and 3.5%, respectively. The mean numbers of adenomas and SSLs were 0.82 and 0.04, respectively. The detection rates of adenomas, high-risk adenomas, and CSSPs increased with looping severity (all P < 0.001). The number of adenomas increased with looping severity (P < 0.001). Multivariate analyses found that detection of adenomas, high-risk adenomas, and CSSPs was associated with severe looping (P < 0.001, P < 0.001, and P = 0.007, respectively) regardless of age, sex, time required for colonoscope insertion and withdrawal, and endoscopist experience.

CONCLUSION

Looping severity was independently associated with high detection rates of premalignant polyps. Therefore, looping may predict the risk of metachronous colorectal cancer. Endoscopists should carefully examine the colorectum of patients with looping.

Colonoscope "Looping" During Ileo-Colonoscopy in Children is Significantly Different to that Observed in Adult Practice

OBJECTIVES

Ileo-colonoscopy (IC) can be technically challenging because of unpredictable colonoscope loop formation. Aims of this study were to assess the risk of loop formation and to attempt to understand which factors were likely to predispose to which subtype of loop.

METHODS

Prospective study conducted on children referred for an IC at Sheffield Children's Hospital. Presence and type of loop was objectively assessed using the magnetic endoscope imaging tool.

RESULTS

Three hundred procedures were prospectively evaluated. Only 9% of paediatric ICs were loop-free. Alpha loops were the most common loop in children older than 5, whereas reverse alpha loops and a wider variety of complex and repetitive loops were observed in younger patients. Once a specific type of loop has formed, the risk of re-looping in a different way or in a different position of the colon is reduced. Left lateral starting position was found to increase the risk of reverse alpha loops and re-looping. Challenging loops, such as reverse alpha, were more frequent in males. Higher body mass index (BMI) was associated with an increased risk of alpha and deep transverse loops formation, while lower BMI with a higher incidence of reverse alpha and N loop. Loop formation did not prevent 100% ileal intubation.

CONCLUSIONS

This study represents the first attempt to describe loop formation according to patient characteristics in a large paediatric series. Further studies are needed in order to establish if these findings could be helpful in simplifying the execution of IC procedures in children and facilitate the learning curve during endoscopy training programs.

Descending-sigmoid colon flexure - An important but surprisingly ignored landmark

BACKGROUND

In invasive examinations of the colon, e.g. colonoscopy, the tortuosity of the colon is a crucial factor for successful completion of the procedure. If adjacent segments of the colon bend at acute angles (under 90°), endoscopy may become difficult and troublesome.

METHODS

We retrospectively enroled 227 individuals (96 female, 131 male) who underwent abdominopelvic computed tomography examination. For inclusion, subjects were required to have a negative history for colonic disease and abdominopelvic surgery. We measured the angle between the descending colon and the proximal part of the sigmoid (in degrees). In addition, the position of the descending-sigmoid flexure was assessed in relation to the left anterior superior iliac spine, the median plane, and anterior aspect of the 5th lumbar vertebra (in mm). The study protocol was reviewed and approved by the local ethics committee.

RESULTS

We visualised the descending-sigmoid flexure in all 227 subjects. In one third of cases, the flexure formed an angle smaller than/or 90°. In females, this landmark (mean ± standard deviation) was located 30.2 ± 8.4 mm from the left anterior superior iliac spine, 88.6 ± 14.2 mm from the median plane, and 115.4 ± 21.4 mm from the anterior aspect of the 5th lumbar vertebra. In males, the dimensions were: 32.1 ± 12.8 mm, 97.6 ± 15.8 mm, and 123.9 ± 22.9 mm, respectively. This landmark distance remained constant from the left anterior superior iliac spine regardless of subject age, height and weight. The other measured distances were related to age, height, weight or BMI.

CONCLUSIONS

The descending-sigmoid flexure is an important landmark in large intestine morphology situated approximately width of two fingers (3 cm) from the left anterior superior iliac spine and one hand width (9-10 cm) from the median plane. In approximately one third of the subjects, the flexure formed an angle of less than/or 90°, which can cause a problem during colonoscopy.

Magnetic endoscopic imaging as a rational investment for specific colonoscopies: a systematic review and meta-analysis

BACKGROUND

Magnetic endoscopic imaging (MEI) was regarded as an adjuvant device to improve procedural efficacy and patients' comfort during colonoscopy.

METHODS

Several electronic databases were searched to identify eligible studies. Based on the heterogeneity of included studies, random-effects or fixed-effects models were used to calculate pooled risk ratios (RR), risk difference (RD) or mean difference (MD) along with 95% confidence intervals (CIs).

RESULTS

Twenty-one randomized controlled trials (RCTs) were selected for meta-analysis, with a total of 7,060 patients. Although there is a slightly lower risk of cecal intubation failure with the adjuvant of MEI (RD 3%; P < 0.00001) compared to the control group, the updated studies show no significant benefits. Similarly, the cecal intubation time, pain scores, and loop formation with the adjuvant of MEI did not show any advantages. However, considerable significant benefits were found in the subgroup of technically difficult colonoscopy and inexperienced colonoscopists. Moreover, MEI was associated with lower loop intubation time, lower abdominal compression times, and better lesion localization.

CONCLUSION

The clinical benefits of MEI could be exaggerated. However, MEI has considerable advantages in technically difficult colonoscopies, the assistance for inexperienced colonoscopists, loop resolving, and lesion localization.

Rare case of torsion of giant ovarian mass post-colonoscopy

We present an unprecedented case of torsion of a large ovarian cyst following colonoscopy. A 43-year-old female was found to have a 20 × 13 × 19 cm pelviabdominal mass possibly arising from the right ovary. Endoscopic evaluation was performed prior to planned resection of the ovarian mass. The patient experienced progressive lower abdominal pain after the procedure with a computed topography finding of torsion. She underwent exploratory laparotomy, right salpingo-oophorectomy with intra-operative frozen section and omentectomy. Final histology revealed features of benign serous cystadenoma with extensive haemorrhagic infarction in keeping with torsion. To our knowledge, this is the first reported case of torsion of a large ovarian cyst after colonoscopy. We propose a postulated mechanism of this patient’s ovarian torsion and urge clinicians to be cognizant of acute ovarian torsion as a cause of severe abdominal pain following endoscopy.

Deformation Modeling of a Flexible Instrument Using a Bézier Curve

Flexible instruments are extensively used in medical applications. Manipulation of these instruments is challenging and troublesome. To study the behavior of these instruments, different modeling approaches like finite element, Cosserat rod, and differential geometry have been used. In this paper, an alternate modeling approach using Bézier curve is proposed to understand large deformation in a flexible instrument. The shape is represented by a Bézier curve. The deformation includes extension, flexure, and torsion in the instrument. Strain energy and geometric constraints are formulated using Bézier control points. The shape of the deformed instrument under the given constraints is obtained by minimizing the total strain energy. Nonlinear constrained optimization is used for the minimization to find the deformed shape. The proposed method is applied for large elastic deformation in three-dimensional space. Loop formation is observed and validated with the experimental results. The proposed method will help in understanding the mechanics of a flexible instrument. Looping is a common problem during colonoscopy. The developed model will help in developing strategies for the safe introduction of these instruments inside the body for performing diagnostic and surgical interventions.

A randomized controlled trial comparing right and left lateral decubitus starting position on outcomes in colonoscopy

BACKGROUND

Patient positioning in colonoscopy has been proposed as a simple and inexpensive technique to increase luminal distention and improve navigation through the large bowel. We sought to determine if the right lateral (RL) starting position compared to the standard left lateral (LL) starting position could improve outcomes in colonoscopy.

METHODS

We conducted a randomized controlled trial of 185 patients who were undergoing an elective colonoscopy. Patients were randomized to either a right lateral decubitus starting position or a left lateral decubitus starting position and the primary outcome measure was cecal intubation time. Secondary outcome measures included cecal intubation rate, patient discomfort, and sedation dosage. All colonoscopists who had successfully completed a colonoscopy skills improvement course were included in the trial. A sample size was calculated prior to the start of the study and outcomes were analyzed using univariate and multiple regression analyses.

RESULTS

A total of 94 patients were randomized to RL starting position and 91 patients were randomized to LL starting position. No difference was found in time to cecal intubation comparing the RL starting position (542.6 s, SD 360.7 s) to LL starting position (497.85 s, SD 288.3 s) (p = 0.354). Variables associated with prolonged cecal intubation time included female gender, General Surgery specialty, less than 5 years of endoscopist experience, a high patient discomfort score, amount of water used, and number of position changes required to reach the cecum. There was no difference in any of the secondary outcome measures aside from the amount of midazolam used, with more midazolam used for patients starting in the right lateral decubitus position.

CONCLUSION

This study failed to show an association between cecal intubation time and patient position comparing right and left lateral starting position.

Use of enteroscope without the overtube in incomplete colonoscopies

Objectives: Colonoscopy is the gold standard diagnostic method for colorectal cancer (CRC) screening. Despite the progress in the endoscopy technology field, a small percentage of colonoscopies is still incomplete. The reasons for that are mostly associated with anatomic features, such as fixed, angulated, long and loopy colon, intra-abdominal adherences and female gender. To overcome such difficulties, the usefulness of scopes different from conventional adult colonoscope (CF), such as paediatric colonoscope (PCF), gastroscope (GIF), single and double balloon enteroscope (SBE and DBE, respectively), has been shown in literature. Our retrospective study aims to evaluate the caecal intubation rate using a SBE without the overtube in patients who previously underwent an incomplete procedure with a different scope.Methods: Patients with a previous incomplete colonoscopy with CF, PCF or GIF were retrospectively enrolled through the analysis of a dedicated database. The enteroscope used was the Olympus Enteropro Single Balloon SiF-Q180 with no overtube. Complete colonoscopy was defined as successful caecal intubation.Results: SBE was used to scope 47 adult patients, mostly female, and it led to a complete procedure in 91% of them. The most frequent reason for an incomplete procedure even with the use of SBE was a fixed and angulated colon.Conclusions: Colonoscopy performed with SBE was safe and no adverse events during and/or after the procedure occurred. Our results suggest that SBE with no overtube is a useful and valid alternative to other type of scopes in difficult cases, especially those related to fixed/angulated colon and in female gender.

(Technically) Difficult colonoscope insertion - Tips and tricks

Cecal intubation is a critical aspect of effective, complete colonoscopy. Difficult colonoscopy is most often considered as one in which it is challenging or impossible to reach the cecum. It may be a common occurrence due to patient and/or endoscopist factors. Incomplete colonoscopies should be avoided, since patients in this context present an important prevalence of lesions that escape examination. The approach to successful cecal intubation should depend on characterization of the problem as redundant colon or difficult sigmoid colon. Most patients with a prior incomplete colonoscopy can be colonoscoped successfully, if careful attention is paid to technique, using a variety of scopes, colonoscopy methods and additional equipment. Sufficient time should be allotted to make the attempt.

Feasibility of Tracking Multiple Implanted Magnets With a Myokinetic Control Interface: Simulation and Experimental Evidence Based on the Point Dipole Model

OBJECTIVE

The quest for an intuitive and physiologically appropriate human-machine interface for the control of dexterous prostheses is far from being completed. To control a hand prosthesis, a possible approach could consist in using information related to the displacement of forearm muscles of an amputee during contraction. We recently proposed that muscle displacement could be monitored by implanting passive magnetic markers (MMs- i.e., permanent magnets) in them. We dubbed this the myokinetic interface. However, besides the system feasibility, how much its accuracy, precision and computation time are affected by the number and distribution of both the MMs and the sensors used to record the MF was not quantified.

METHODS

Here we investigated, through simulations validated with a physical system, the performance of a system capable to track position and orientation of up to 9 MMs using information from up to 112 sensors in a volume resembling the dimensions of the human forearm.

RESULTS

The system was able to track up to 7 MMs in 450 ms, demonstrating position/orientation accuracies in the range of 1 mm/5°. The comparison with the experimental recordings demonstrated a median difference with the simulations in the order of 0.45 mm.

CONCLUSION

We were able to formulate general guidelines for the implementation of magnetic tracking systems.

SIGNIFICANCE

Our results pave the way towards the development of new human-machine interfaces for the control of artificial limbs, but they are also interesting for the whole range of biomedical engineering applications exploiting magnetic tracking.

Soft Robotics in Minimally Invasive Surgery

Soft robotic devices have desirable traits for applications in minimally invasive surgery (MIS), but many interdisciplinary challenges remain unsolved. To understand current technologies, we carried out a keyword search using the Web of Science and Scopus databases, applied inclusion and exclusion criteria, and compared several characteristics of the soft robotic devices for MIS in the resulting articles. There was low diversity in the device designs and a wide-ranging level of detail regarding their capabilities. We propose a standardized comparison methodology to characterize soft robotics for various MIS applications, which will aid designers producing the next generation of devices.

The large intestine from fetal period to adulthood and its impact on the course of colonoscopy

The human large intestine in the living adult has a total length of about 1300 mm, ranging from 1100 to 2108 mm. The development of the gut continues after birth, up to the age 4-5. The large intestine ascends at the beginning in the right abdominal quadrant, then it traverses the abdominal cavity, and finally it descends to the anus. The left and right colic flexures are the basic flexions between the transverse, ascending and descending colon, respectively. Additionally, there are secondary bendings between intestinal segments. The angles between the neighbouring parts can vary between examined subjects. Most of the angulations can be found in the transverse (range 2-9) and sigmoid colon (range 1-9), making them the most troublesome parts to pass with a colonoscope. Colonoscopy (usually performed in the left lateral or supine position) is one of the most important examination of the large intestine mucus membrane. During this procedure the endoscope is passed through the colon into the cecum or terminal ilium. The individual anatomical features (tortuosity, supernumerary loops and elongation) may slow down or interfere with the progress of the scope. We summarize current knowledge on the human large intestine from the fetal period to adulthood and carve out some aspects that are currently less known to colonoscopists.

Prone or Left for Colonoscopy? A Randomized Controlled Trial of Prone Versus Left-sided Starting Position for Colonoscopy

BACKGROUND AND AIMS

Data have emerged supporting the right-lateral starting position in reducing time to cecum and improving patient comfort for minimally sedated colonoscopy. We aimed to test whether prone starting position results in similar advantages in procedure time and patient tolerability in comparison to traditional left-sided starting position.

MATERIALS AND METHODS

We conducted a randomized controlled trial in which patients were randomized to begin in either the prone or left-lateral (LL) position. A total of 181 adult patients undergoing scheduled colonoscopy were stratified by age, gender, body mass index, and experience of the endoscopist. Patients were then randomized 1:1 in permuted blocks. The primary outcome measure was time to cecal intubation and secondary outcome measures included patient comfort that was measured by visual analog scale.

RESULTS

There was no benefit from prone starting positioning over conventional left-sided starting positioning. Further, prone starting position led to an increase in time to reach cecum (701 vs. 511 s; P=0.01). This could be in part explained by an increased time to reach transverse colon in patients positioned prone (332 vs. 258 s; P=0.06). Comfort levels were similar between patients positioned prone and LL (4 vs. 4 visual analog scale; P=0.6) although endoscopists found colonoscopies in which patients started prone more technically challenging than if started LL (5 vs. 4; P=0.002).

CONCLUSIONS

Prone starting position did not improve time to reach cecum or patient comfort for minimally sedated patients undergoing colonoscopy. The ClinicalTrials.gov identifier is NCT02305706.

Use of an abdominal obstetric binder in colonoscopy: A randomized, prospective trial

BACKGROUND AND AIMS

Various methods have been reported as aids to cecal intubation. This study aimed to prospectively investigate whether an abdominal obstetric binder (AOB) used during pregnancy and attached to the patients' abdomen during colonoscopy could facilitate effective colonoscopic insertion.

METHODS

This was a prospective study of 451 consecutive outpatient colonoscopies performed by a single experienced endoscopist. The recruited patients were randomly separated into two groups that received colonoscopy either with (Group A) or without an AOB attached (Group B). The cecal intubation time, cecal intubation length of the colonoscope, use of manual pressure, position change of each patient, and the number of patients with abdominal distension were collected for comparison.

RESULTS

A total of 451 patients (224 in Group A and 227 in Group B) were ultimately included in this study. In Group A, cecal intubation time and cecal intubation length of colonoscope (CIL) were significantly reduced (P < 0.001). The patients had significantly fewer position changes and manual pressure in Group A (P < 0.001). Significantly less abdominal distension was reported by patients in Group A (P < 0.001).

CONCLUSIONS

During colonoscopy, the application of an AOB provided a significantly faster and more effective colonoscope insertion.

Detection of endoscopic looping during colonoscopy procedure by using embedded bending sensors

Background

Looping of the colonoscope shaft during procedure is one of the most common obstacles encountered by colonoscopists. It occurs in 91% of cases with the N-sigmoid loop being the most common, occurring in 79% of cases.

Purpose

Herein, a novel system is developed that will give a complete three-dimensional (3D) vector image of the shaft as it passes through the colon, to aid the colonoscopist in detecting loops before they form.

Patients and methods

A series of connected links spans the middle 50% of the shaft, where loops are likely to form. Two potentiometers are attached at each joint to measure angular deflection in two directions to allow for 3D positioning. This 3D positioning is converted into a 3D vector image using computer software. MATLAB software has been used to display the image on a computer monitor. For the different configuration of the colon model, the system determined the looping status.

Results

Different configurations (N loop, reverse gamma loop, and reverse splenic flexure) of the loops were well defined using 3D vector image.

Conclusion

The novel sensory system can accurately define the various configuration of the colon during the colonoscopy procedure.

Difference in real-time magnetic image analysis of colonic looping patterns between males and females undergoing diagnostic colonoscopy

Background and study aim Magnetic imaging technology is of proven benefit to trainees in colonoscopy, but few studies have examined its benefits in experienced hands. There is evidence that colonoscopy is more difficult in women. We set out to investigate (i) associations between the looping configurations in the proximal and distal colon and (ii) differences in the looping prevalence between the sexes. We have examined their significance in terms of segmental intubation times and position changes required for the completion of colonoscopy.

Patients and methods We analyzed 103 consecutive synchronized luminal and magnetic image videos of diagnostic colonoscopies with normal anatomy undertaken by a single experienced operator.

Results Deep transverse loops and sigmoid N-loops were more common in females. A deep transverse loop was more likely to be present if a sigmoid alpha-loop or N-loop had formed previously. Patients with sigmoid N-loops were turned more frequently from left lateral to supine before the sigmoid-descending junction was reached, but there was no statistical correlation between completion time and looping pattern.

Conclusions This study has reexamined the prevalence of the common looping patterns encountered during colonoscopy and has identified differences between the sexes. This finding may offer an explanation as to why colonoscopy has been shown to be more difficult in females. Although a deep transverse loop following a resolved sigmoid alpha-loop was the most commonly encountered pattern, no statistical correlation between completion time and looping pattern could be shown. It is the first study to examine segmental completion times using a magnetic imager in expert hands.

Longer observation time increases adenoma detection in the proximal colon - a prospective study

BACKGROUND AND STUDY AIMS

Longer observation times are associated with increased adenoma detection rates (ADR) in the entire colon. However, adenomas in the proximal colon are at risk of being missed during colonoscopy. The aim of this study was to investigate the impact of observation time on detection of adenomatous polyps in the proximal colon.

PATIENTS AND METHODS

This was a prospective study at a university hospital in Germany. Colonoscopies were conducted using magnetic endoscope imaging (MEI) in order to determine the exact position of the scope. Exact observation times spent for the detection of polyps in the proximal and distal colon segments were assessed. The primary outcome was adenoma detection in the proximal colon. ROC curves were generated in order to test the correlation between observation time and adenoma detection. Logistic regression analysis was used to check for interfering factors.

RESULTS

 A total 480 procedures with 538 polyps were available for analysis. The overall adenoma detection rate was 38.5 %. ADR in the proximal colon was 28.0 %. There was a significant association between observation time in the proximal colon and the detection of proximal adenomas ( P  < 0.001). The impact of the time factor on ADR was stronger in the proximal compared to the distal colon ( P  = 0.030). A net period of 4 min 7 sec was found to be the minimum time span for sufficient adenoma detection in the proximal colon.

CONCLUSION

Observation time is significant in terms of adenoma detection in the proximal colon. The impact of observation time on ADR is stronger in the proximal compared to the distal colon. In the proximal colon a minimum time span of 4 minutes should be spent in order to ensure adequate adenoma detection.

A novel physical colonoscopy simulator based on analysis of data from computed tomography colonography

Purpose

Laparoscopic surgery is now practiced widely because of its lower postoperative morbidity. As flexible endoscopy during laparoscopic surgery minimizes surgical trauma further, training in endoscopy will become more important for surgeons. Thus, we designed a physical simulator, the Noda–Kitada–Suzuki (NKS) model, which could provide the more realistic insertion of a colonoscope.

Methods

We designed a colonoscopy simulator, based on information from computed tomography colonography scans of the anatomy and kinetic properties of the colon and rectum.

Results

The transparent skeleton body of the NKS model provides instant visual feedback to the operator and the trainer. Our novel colonoscopy simulator replicates the realistic and reproducible insertion of a colonoscope from the rectum to cecum, providing authentic views of the Houston’s valves, the flexures, and mucosal folds. This was verified through an objective questionnaire, with 14 of 16 colonoscopists preferring the NKS model over the previous CM15 model for training purposes. Moreover, the Modified Colonoscopy Simulator Realism Questionnaire analysis confirmed that the NKS model was significantly more realistic than the CM15 for 7 (21.2%) of the 33 items when assessed by 12 colonoscopists.

Conclusion

The NKS model provides a realistic training platform and may improve the quality of training in colonoscopy.

Electronic supplementary material

The online version of this article (doi:10.1007/s00595-017-1517-7) contains supplementary material, which is available to authorized users.

Colorectal cancer anatomic distribution patterns remain the same after sessile serrated adenoma/polyp considered cancer precursor: a 9-year comparison study from community-based endoscopy centers

BACKGROUND

The overall incidence of colorectal cancer (CRC) in the United States has steadily decreased. However, the incidence of right-sided CRC remains unchanged for the past two decades. The serrated neoplastic pathway (sessile serrated adenoma/polyp, SSA/P) has been considered an important pathway of colorectal carcinogenesis, especially in the right-sided CRC. The aim of this study was to compare CRC anatomic distribution patterns in a 9-year interval in the general population before and after SSA/P was recognized and treated as a CRC precursor.

METHODS

The Miraca Life Sciences (MLS) pathology database was queried for all primary CRCs diagnosed between 8/3/2000 to 12/31/2005 (control group) and 1/1/2014 to 12/31/2014 (current group). Patients' demographics, clinical information, and pathology reports were collected and analyzed.

RESULTS

A total of 5,602 patients with 5,685 CRCs were identified, of which 2,728 patients with 2,765 CRCs in current group and 2,874 patients with 2,920 CRCs in control group. Overall, there were no statistical differences in the current group in regards to the anatomical distribution patterns of CRCs in the proximal, right-sided, distal, and left-sided colon or genders compared with the control group (all P>0.05). Among the current group, there were 33 (1.2%) patients with 38 (1.4%) CRCs arising in SSA/Ps [serrated carcinomas (SCAs)], of which 33 (86.8%) were in the right-sided colon and 5 (13.2%) in the left-sided colon. Twenty-three (69.7%) SCA patients were female with significant advanced age than male (76.4 vs. 69.6, P=0.023).

CONCLUSIONS

The overall current CRC anatomic distribution patterns after SSA/Ps managed as CRC precursor remain the same in the patients' population from the community-based endoscopy centers in the U.S. It is suggested that the current SSA/P management might need to be further modified.

Use of an Abdominal Compression Device in Colonoscopy: A Randomized, Sham-Controlled Trial

BACKGROUND & AIMS

Looping is a common problem during colonoscopy that prolongs procedure time. We aimed to determine the efficacy and safety of ColoWrap, an external abdominal compression device, with respect to insertion time and other procedural outcomes.

METHODS

We performed a prospective study of outpatients undergoing elective colonoscopy (40-80 years old; mean age, 60.5 years) at endoscopy facilities in the University of North Carolina Hospitals from April 2013 through March 2014. Subjects were randomly assigned to groups that received either ColoWrap (n = 175) or a sham device (control, n = 175) during colonoscopy. Colonoscopists and staff were blinded to the application. The primary outcome was cecal intubation time (CIT). Secondary outcomes included use of manual pressure and position change.

RESULTS

The mean CIT was similar for the control and ColoWrap groups (6.69 vs 6.67 minutes; P = .98). There were no statistical differences in the frequency of manual pressure (45% for controls vs 37% for ColoWrap group, P = .13) or position changes (4% for controls vs 2% for ColoWrap group, P = .36). Among patients with body mass index between 30 and 40 kg/m(2) (n = 78), CIT was significantly lower for patients in the ColoWrap group (4.69 minutes) than controls (6.10 minutes) (P = .03). Adverse events were similar between groups.

CONCLUSIONS

In patients undergoing elective colonoscopy, application of an external abdominal compression device did not improve CIT or affect the frequency of ancillary maneuvers. A possible benefit was observed in patients with body mass index between 30 and 40 kg/m(2), but further studies are needed. ClinicalTrials.gov number: NCT02025504.

Robotic-assisted flexible colonoscopy: preliminary safety and efficiency in humans

BACKGROUND AND AIMS

The flexible endoscope is used as a platform for minimally invasive interventions. However, control of the conventional endoscope and multiple instruments is difficult. Robotic assistance could provide a solution and better control for a single operator. A novel platform should also enable interventions in areas that are currently difficult to reach. This study evaluates the safety and efficacy of a robotic platform that guides a conventional endoscope through the large bowel.

METHODS

Adult patients scheduled for routine diagnostic colonoscopy were included in this feasibility study. The endoscope was introduced using a robotic add-on to provide tip bending and air/water actuation. The endoscopist directly controlled the endoscope shaft. Upon cecal intubation, the add-on was detached and the procedure continued using conventional control. Primary evaluation parameters were the number of serious adverse events and the percentage of successful cecal intubations.

RESULTS

The procedure was performed on 22 consecutive patients who all gave informed consent. There were no serious adverse events. Cecal intubation was successful in 15 patients (68%) using the robotic add-on. Six cases were completed after conversion to conventional control: 3 cases were converted to pass sharp angulation in the flexures and 3 cases were converted after technical difficulties. One case was not successful with either technique because of severe diverticulosis.

CONCLUSIONS

The robotic add-on steering module allows safe endoscope intubation to reach intervention sites throughout the large bowel. The next step is to clinically evaluate complementary instrument and shaft-guiding modules in therapeutic procedures.

Accuracy of polyp localization at colonoscopy

BACKGROUND AND STUDY AIMS

Accurate documentation of lesion localization at the time of colonoscopic polypectomy is important for future surveillance, management of complications such as delayed bleeding, and for guiding surgical resection. We aimed to assess the accuracy of endoscopic localization of polyps during colonoscopy and examine variables that may influence this accuracy.

PATIENTS AND METHODS

We conducted a prospective observational study in consecutive patients presenting for elective, outpatient colonoscopy. All procedures were performed by Australian certified colonoscopists. The endoscopic location of each polyp was reported by the colonoscopist at the time of resection and prospectively recorded. Magnetic endoscope imaging was used to determine polyp location, and colonoscopists were blinded to this image. Three experienced colonoscopists, blinded to the endoscopist's assessment of polyp location, independently scored the magnetic endoscope images to obtain a reference standard for polyp location (Cronbach alpha 0.98). The accuracy of colonoscopist polyp localization using this reference standard was assessed, and colonoscopist, procedural and patient variables affecting accuracy were evaluated.

RESULTS

A total of 155 patients were enrolled and 282 polyps were resected in 95 patients by 14 colonoscopists. The overall accuracy of polyp localization was 85 % (95 % confidence interval, CI; 60 - 96 %). Accuracy varied significantly (P < 0.001) by colonic segment: caecum 100 %, ascending 77 % (CI;65 - 90), transverse 84 % (CI;75 - 92), descending 56 % (CI;32 - 81), sigmoid 88 % (CI;79 - 97), rectum 96 % (CI;90 - 101). There were significant differences in accuracy between colonoscopists (P < 0.001), and colonoscopist experience was a significant independent predictor of accuracy (OR 3.5, P = 0.028) after adjustment for patient and procedural variables.

CONCLUSIONS

Accuracy of localization of polyps is imprecise and affected by position within the colon and colonoscopist, including their level of experience. Magnetic endoscope imaging may improve the localization of lesions during colonoscopy.

Feasibility of automated target centralization in colonoscopy

Purpose

Early detection of colorectal cancer is key to full recovery. This urged governments to start population screening programs for colorectal cancer, often using flexible endoscopes. Flexible endoscopy is difficult to learn and time-consuming. Automation of flexible endoscopes may increase the capacity for the screening programs. The goal of this pilot study is to investigate the clinical and technical feasibility of an assisting automated navigation algorithm for a colonoscopy procedure.

Methods

Automated navigation (lumen centralization) was implemented in a robotized system designed for conventional flexible endoscopes. Ten novice and eight expert users were asked to perform a diagnostic colonoscopy on a colon model twice: once using the conventional and once using the robotic system. Feasibility was evaluated using time and location data as measures of the system’s added value.

Results

Automated target centralization (ATC) was turned on by the novices for a median of 4.2 % of the time during insertion and 0.3 % during retraction. Experts turned ATC on for 4.0 % of the time during insertion and 11.6 % during retraction. Novices and experts showed comparable times to reach the cecum with the conventional or the robotic setup with ATC.

Conclusion

The ATC algorithm combined with the robotized endoscope setup works in an experimental setup that closely resembles the clinical environment and is considered feasible, although ATC use was lower than expected. For novices, it was unclear whether the low usage was due to unfamiliarity with the system or because they did not need ATC. Experts used ATC also during the retraction phase of the procedure. This was an unexpected finding and may indicate an added value of the system.

Electronic supplementary material

The online version of this article (doi:10.1007/s11548-015-1301-3) contains supplementary material, which is available to authorized users.

Feasibility of joystick guided colonoscopy

The flexible endoscope is increasingly used to perform minimal invasive interventions. A novel add-on platform allows single-person control of both endoscope and instrument at the site of intervention. The setup changes the current routine of handling the endoscope. This study aims to determine if the platform allows effective and efficient manipulation to position the endoscope at potential intervention sites throughout the bowel. Five experts in flexible endoscopy first performed three colonoscopies on a computer simulator using the conventional angulation wheels. Next they trained with the joystick interface to achieve their personal level of intubation time with low pain score. 14 PhD students (novices) without hands-on experience performed the same colonoscopy case using either the conventional angulation wheels or joystick interface. Both novice groups trained to gain the average expert level. The cecal intubation time, pain score and visualization performance (% of bowel wall) were recorded. All experts reached their personal intubation time in 6 ± 6 sessions. Three experts completed their learning curve with low pain score in 8 ± 6 sessions. The novices required 11 ± 6 sessions using conventional angulation wheels, and 12 ± 6 sessions using the joystick interface. There was no difference in the visualization performance between the novice and between the expert groups. This study shows that the add-on platform enables endoscope manipulation required to perform colonoscopy. Experts need only a relatively short training period. Novices are as effective and as efficient in endoscope manipulation when comparing the add-on platform with conventional endoscope control.

Magnetic endoscope imaging in single-balloon enteroscopy

BACKGROUND AND AIM

Magnetic endoscope imaging (MEI) provides continuous viewing of the position of the endoscope on a monitor without using X-ray and has already been established for colonoscopy. The aim of the present study was to evaluate a new MEI probe for enteroscopy.

METHODS

In this prospective feasibility study, consecutive patients received single-balloon enteroscopy guided by the new MEI probe. Fluoroscopy was also used in all examinations. MEI images were compared to fluoroscopy images with respect to concordance of loop configuration by two independent observers after the examinations. Main outcome measurement was the rate of concordant MEI and fluoroscopy images with respect to loop configuration.

RESULTS

In all 10 patients, single-balloon enteroscopy with MEI was carried out without any adverse events or technical difficulties. Concordance of MEI and fluoroscopy images was seen in 36/38 images (95%; 95% CI, 82-99%) by both observers. Overall agreement between the two observers was 95% (κ = 0.47, 95% CI, -0.04-1).

CONCLUSION

The use of MEI in single-balloon enteroscopy is safe and feasible. Detection and control of loops can be accurately achieved.

Diffusion-weighted MR enterography for evaluating Crohn's disease: how does it add diagnostically to conventional MR enterography?

BACKGROUND

Diffusion-weighted imaging (DWI) is a novel technique to evaluate bowel inflammation in Crohn's disease (CD). It is unknown whether and how DWI adds to the accuracy of conventional magnetic resonance enterography (MRE).

METHODS

Fifty consecutive adults suspected of CD prospectively underwent clinical assessment, conventional MRE and DWI at b = 900 sec/mm without water enema, and ileocolonoscopy within 1 week. MRE images were interpreted with proper blinding. Forty-four patients finally diagnosed with CD (male:female, 34:10; 26.9 ± 6.1 yr) were analyzed. The per-segment accuracy of MRE for diagnosing active CD was assessed in the terminal ileum, right colon, and rectum using location-by-location matching with endoscopy as the reference standard.

RESULTS

The study evaluated 58 bowel segments with deep or superficial ulcers, 34 with aphthae, erythema, or edema only, and 35 without inflammation. Conventional MRE + DWI was more sensitive for bowel inflammation than conventional MRE alone (83% [76/92] versus 62% [57/92]; P = 0.001) largely because of additional detection of aphthae, erythema, or edema. The sensitivities for deep and overt ulcers were similar regardless of DWI, ranging from 88% to 97%. Conventional MRE + DWI was less specific than conventional MRE alone (60% [21/35] versus 94% [33/35]; P < 0.001), mostly because of many false positives in the colorectum. Positive DWI findings in the bowel showing active inflammation on conventional MRE were associated with higher Crohn's disease endoscopic index of severity score (P = 0.021) and deep ulcers (P = 0.01; diagnostic odds ratio, 12).

CONCLUSIONS

DWI performed without water enema is not useful for incremental detection of bowel inflammation. DWI may help identify more severe inflammation among bowel segments showing active inflammation on conventional MRE.

Factors that determine prolonged cecal intubation time during colonoscopy: impact of visceral adipose tissue

OBJECTIVE

Various factors including age, sex, body mass index (BMI) and history of operation have been linked to the colonoscopic intubation time. The aims of this study were to identify the factors predicting cecal intubation time (CIT) and to evaluate the effect of the visceral adipose tissue (VAT) area on CIT.

MATERIAL AND METHODS

A total of 1386 consecutive subjects who underwent colonoscopy and abdominal CT on the same day for a health checkup at a single health care center in Korea from August to December 2011 were studied prospectively. Age, sex, BMI, height, waist circumference, history of operation, symptoms of irritable bowel syndrome, bowel preparation status, experience of colonoscopists, VAT amount on abdominal CT and time required to reach the cecum were analyzed.

RESULTS

The mean age of the subjects was 53.0 ± 9.6 years, and 63.5% were male. The median CIT was 271 s. Univariate analyses showed that female gender, old age, shorter height, lower BMI, prior history of surgery and lower VAT were associated with longer CIT. To adjust for confounding effects of the gender, we investigated the genders separately in multivariate analysis. Older age and lower VAT were associated with prolonged CIT. However, the significance of association of VAT on prolonged CIT disappeared in women.

CONCLUSION

This study demonstrates that CIT is prolonged by lower VAT area in men. This is the first study to demonstrate a direct association between VAT area and CIT.

Development of the gastrointestinal endoscopy competency assessment tool for pediatric colonoscopy (GiECAT KIDS)

OBJECTIVES

Many aspects of pediatric colonoscopy differ from adult practice. To date, there is no validated measure of endoscopic competence for use in pediatrics. Using Delphi methodology, we aimed to determine expert consensus regarding items required on a checklist and global rating scale designed to assess the competence of clinicians performing colonoscopy on pediatric patients.

METHODS

A total of 41 North American pediatric endoscopy experts rated potential checklist and global rating items for their importance as indicators of the competence of trainees learning to perform pediatric colonoscopy. Responses were analyzed and re-sent to the panel for further ratings until consensus was reached. Items that ≥ 80% of experts rated as ≥ 4 out of 5 were included in the final instrument. Consensus items were compared with those items deemed by adult endoscopy experts as fundamental to assessing the performance of adult colonoscopy.

RESULTS

Five rounds of surveys were completed with response rates ranging from 76% to 100%. Seventy-five checklist and 38 global rating items were reduced to 18 checklist and 7 global rating items that reached consensus. Three pediatric checklist items differed from those considered to be critical adult indicators, whereas 4 items on the latter did not reach consensus among pediatric experts.

CONCLUSIONS

Delphi methodology allowed for achievement of expert consensus regarding essential items to be included in the Gastrointestinal Endoscopy Competency Assessment Tool for Pediatric Colonoscopy (GiECATKIDS), a measure of endoscopic competence specific to performing pediatric colonoscopy. Key differences in the checklist items, compared with items reaching consensus during a separate adult Delphi process using the same indicators, emphasize the need for a pediatric-specific tool.

Magnetic imaging-assisted colonoscopy vs conventional colonoscopy: A randomized controlled trial

AIM: To compare magnetic imaging-assisted colonoscopy (MIC) with conventional colonoscopy (CC).

METHODS: Magnetic imaging technology provides a computer-generated image of the shape and position of the colonoscope onto a monitor to give visual guidance to the endoscopist. It is designed to improve colonoscopy performance and tolerability for patients by enabling visualization of loop formation and endoscope position. Recently, a new version of MIC technology was developed for which there are limited data.To evaluate this latest generation of MIC among experienced rather than inexperienced or trainee endoscopists, a prospective randomized trial was performed using only gastroenterologists with therapeutic endoscopy training. Consecutive patients undergoing elective outpatient colonoscopy were randomized to MIC or CC, with patients blinded to their group assignment. Endoscopic procedural metrics and quantities of conscious sedation medications were recorded during the procedures. The procedure was classified as “usual” or “difficult” by the endoscopist at the conclusion of each case based on the need for adjunctive maneuvers to facilitate endoscope advancement. After more than one hour post-procedure, patients completed a 10 cm visual analogue pain scale to reflect the degree of discomfort experienced during their colonoscopy. The primary outcome was patient comfort expressed by the visual analogue pain score. Secondary outcomes consisted of endoscopic procedural metrics as well as a sedation score derived from standardized dose increments of the conscious sedation medications.

RESULTS: Two hundred fifty-three patients were randomized and underwent MIC or CC between September 2011 and October 2012. The groups were similar in terms of the indications for colonoscopy and patient characteristics. There were no differences in cecal intubation rates (100% vs 99%), insertion distance-to-cecum (82 cm vs 83 cm), time-to-cecum (6.5 min vs 7.2 min), or polyp detection rate (47% vs 52%) between the MIC and CC groups. The primary outcome of mean pain score (1.0 vs 0.9 out of 10, P = 0.41) did not differ between MIC and CC groups, nor did the mean sedation score (8.2 vs 8.5, P = 0.34). Within the subgroup of cases considered more challenging or difficult, time-to-cecum was significantly faster with MIC compared to CC, 10.1 min vs 13.4 min respectively (P = 0.01). Sensitivity analyses confirmed a similar pattern of overall findings when each endoscopist was considered separately, demonstrating that the mean results for the entire group were not unduly influenced by outlier results from any one endoscopist.

CONCLUSION: Although the latest version of MIC resulted in faster times-to-cecum within a subgroup of more challenging cases, overall it was no better than CC in terms of patient comfort, sedation requirements and endoscopic procedural metrics, when performed in experienced hands.

Patient-posture and Ileal-intubation during colonoscopy (PIC): a randomized controlled open-label trial

BACKGROUND AND AIMS

Patient's posture change is commonly employed by a colonoscopist to achieve complete examination. We studied whether patient's posture (left-lateral decubitus vs supine) influenced the success rate of ileal intubation.

PATIENTS AND METHODS

In this prospective open-label randomized study performed in the Endoscopy Suite of a tertiary-care center, all adult outpatients referred for colonoscopy, in whom cecal intubation was achieved and who satisfied predefined inclusion criteria, were randomized to undergo ileal intubation in either of the above two postures. Colonoscopy (EC-201 WL, Fujinon) was performed after overnight poly-ethylene-glycol preparation, under conscious sedation and continuous pulse-oxymetry monitoring. After confirming cecal intubation, patients were randomized for ileal intubation. Success was defined by visualization of ileal mucosa or villi (confirmed by digital photography) and was attempted until limited by pain and/or time of ≥ 6 min.

RESULTS

Of 320 eligible patients, 217 patients (150 males) were randomized, 106 to left-lateral decubitus and 111 to supine posture. At baseline, the two groups were evenly matched. Successful ileal intubation was achieved in 145 (66.8 %) patients overall, significantly higher in the supine posture (74.8 % versus 58.5 %; P = 0.014). On multivariate analysis, supine posture (P = 0.02), average/good right-colon preparation (P < 0.01), non-thin-lipped ileocecal (IC) valve (P < 0.001) and younger age (P = 0.02) were independent predictors of success. Positive ileal findings were recorded in 13 (9 %) patients.

CONCLUSION

Ileoscopy is more successful in supine than in left-lateral decubitus posture. Age, bowel preparation and type of IC valve also determine success.

Robotics in Colonoscopy

Colorectal cancer is the second leading cause of mortality in men and women in the United States. While there is a definite advantage regarding the use of colonoscopies in screening, there is still a lack of widespread acceptance of colonoscopy use in the general public. This is evident by the fact that up to 75% of patients diagnosed with colorectal cancer present with locally advanced disease. In order to make colonoscopy and in turn colorectal cancer screening a patient friendly and a comfortable test some changes in tool are necessary. The conventional colonoscope has not changed much since its development. There are several new advances in colorectal screening practices. One of the most promising new advances is the advent of robotic endoscopic techniques.

Validation of the National Aeronautics and Space Administration Task Load Index as a tool to evaluate the learning curve for endoscopy training

BACKGROUND

Although workplace workload assessments exist in different fields, an endoscopy-specific workload assessment tool is lacking.

OBJECTIVE

To validate such a workload tool and use it to map the progression of novice trainees in gastroenterology in performing their first endoscopies.

METHODS

The National Aeronautics and Space Administration Task Load Index (NASA-TLX) workload assessment tool was completed by eight novice trainees in gastroenterology and 10 practicing gastroenterologists⁄surgeons. An exploratory factor analysis was performed to construct a streamlined endoscopy-specific task load index, which was subsequently validated. The 'Endoscopy Task Load Index' was used to monitor progression of trainee exertion and self-assessed performance over their first 40 procedures.

RESULTS

From the factor analysis of the NASA-TLX, two principal components emerged: a measure of exertion and a measure of self-efficacy. These items became the components of the newly validated Endoscopy Task Load Index. There was a steady decline in self-perceived exertion over the training period, which was more rapid for gastroscopy than colonoscopy. The self-efficacy scores for gastroscopy rapidly increased over the first few procedures, reaching a plateau after this period of time. For colonoscopy, there was a progressive increase in reported self-efficacy over the first three quartiles of procedures, followed by a drop in self-efficacy scores over the final quartile.

DISCUSSION

The present study validated an Endoscopy Task Load Index that can be completed in <1 min. Practical implications of such a tool in endoscopy education include identifying periods of higher perceived exertion among novice endoscopists, facilitating appropriate levels of guidance from trainers.

The use of ancillary techniques to aid colonoscope insertion

BACKGROUND

There is more to a high-quality colonoscopy than reaching the cecum or finding adenomas. Gentle insertion involves ancillary techniques, some of which are impossible in patients receiving deep sedation. The aim of this study was to assess the importance of ancillary techniques in achieving a comfortable, complete colonoscopy.

METHODS

This was a prospective study of 500 consecutive outpatient colonoscopies performed by a single endoscopist. During the procedure, note was taken of various ancillary techniques used to facilitate insertion: turning the patient, patient holding their breath, abdominal pressure. The success of these techniques in helping scope advancement was also noted. After the procedure the patient was asked to rate the severity of their pain and their degree of satisfaction with the examination.

RESULTS

A total of 238 women and 262 men participated in the study, and colonoscopy was complete in 96.2 and 98.5%, respectively. Overall, 97% of patients received versed alone (average dose 2 mg), and 3% received a narcotic (average dose 46 U). Average pain score was 3.9 on a scale of 1 (least pain) to 10 (worst pain), and average satisfaction with the procedure as a whole was 9.5 on a similar scale. Ancillary techniques of holding breath, directed abdominal pressure, and turning to the left, right, and prone were used in 46, 56, 17, 23, and 4% of examinations, respectively. Each technique was effective in helping insertion in over 70% of cases. Turning the patient was also used to clear stool, open the colon, or facilitate polypectomy in another 33 cases. Multiple techniques were used in 49% of patients.

CONCLUSION

The use of ancillary techniques to facilitate colonoscope insertion helps avoid the expense and potential side effects of deep sedation.

Mechanical analysis of insertion problems and pain during colonoscopy: why highly skill-dependent colonoscopy routines are necessary in the first place... and how they may be avoided

BACKGROUND

Colonoscopy requires highly skill-dependent manoeuvres that demand a significant amount of training, and can cause considerable discomfort to patients, which increases the use of sedatives. Understanding the underlying fundamental mechanics behind insertion difficulties and pain during colonoscopy may help to simplify colonoscopy and reduce the required extent of training and reliance on sedatives.

METHODS

A literature search, anatomical studies, models of the colon and colonoscope, and bench tests were used to qualitatively analyze the fundamental mechanical causes of insertion difficulties and pain. A categorized review resulted in an overview of potential alternatives to current colonoscopes.

RESULTS

To advance a colonoscope through the colon, the colon wall, ligaments and peritoneum must be stretched, thus creating tension in the colon wall, which resists further wall deformation. This resistance forces the colonoscope to bend and follow the curves of the colon. The deformations that cause insertion difficulties and pain (necessitating the use of complex conventional manoeuvres) are the stretching of ligaments, and stretching of colon wall in the transverse and longitudinal directions, and the peritoneum.

CONCLUSIONS

Four fundamental mechanical solutions to prevent these deformations were extracted from the analysis. The current results may help in the development of new colonoscopy devices that reduce - or eliminate - the necessity of using highly skill-dependent manoeuvres, facilitate training and reduce the use of sedatives.

CT colonography for investigation of patients with symptoms potentially suggestive of colorectal cancer: a review of the UK SIGGAR trials

This paper argues for the use of CT colonography (CTC) to investigate patients with symptoms potentially suggestive of colorectal cancer. It describes the rationale for the UK Special Interest Group in Gastrointestinal and Abdominal Radiology (SIGGAR) randomised controlled trials that compared CTC with barium enema (BE) or colonoscopy for diagnosis of colorectal cancer or large polyps in symptomatic patients. Diagnostic outcomes from the trials are detailed for both intra- and extracolonic disease, along with psychological reactions of patients to the tests, and cost-effectiveness of the different diagnostic strategies. The author concludes that BE should be replaced by CTC immediately and that CTC is a sensitive, acceptable and equally cost-effective alternative to colonoscopy in patients in whom colonoscopy is contraindicated or undesirable.

Randomized trial of standard versus magnetic endoscope imaging colonoscopes for unsedated colonoscopy

BACKGROUND

Unsedated colonoscopy has potential benefits, including decreased costs and decreased risks.

OBJECTIVE

To determine whether patient comfort during unsedated colonoscopy can be improved through the use of a magnetic endoscopic imaging (MEI) colonoscope compared with a standard colonoscope.

DESIGN

Prospective, patient-blinded, randomized, controlled trial.

SETTING

San Francisco Veterans Affairs Medical Center.

PATIENTS

Veterans undergoing outpatient screening or surveillance colonoscopy.

INTERVENTIONS

Use of a standard or MEI colonoscope during unsedated colonoscopy.

MAIN OUTCOME MEASUREMENT

The primary outcome variable was patient perception of pain using a 7-point scale. The secondary endpoint was patient willingness to undergo a future unsedated colonoscopy.

RESULTS

Of the 160 patients enrolled, 140 completed an unsedated colonoscopy in the study protocol. In a per-protocol analysis, the mean and median pain score was 3.12 (standard deviation 1.22) and 4 (interquartile range 2-4) for the standard colonoscope group and 3.06 (standard deviation 1.13) and 3 (interquartile range 2-4) for the MEI group, where 3 was mild pain (P = not significant). Overall, 80% of subjects were willing to undergo a future unsedated colonoscopy for screening or surveillance. In an intention-to-treat analysis, 80% of subjects (64/80) in the standard colonoscope arm and 79% in the MEI arm (63/80) were willing to undergo a future unsedated colonoscopy (P = not significant).

LIMITATIONS

Single-center study of mostly male veterans.

CONCLUSIONS

This patient-blinded, randomized, controlled trial did not demonstrate any difference in patient perception of pain or willingness to undergo unsedated examinations when using the MEI versus the conventional colonoscope. Unsedated colonoscopy is generally feasible and well tolerated and is associated with high patient satisfaction rates.

Abdominal Palpation Haptic Device for Colonoscopy Simulation Using Pneumatic Control

In this paper, we describe the development of a haptic device to be used in a simulator aiming to train the skills of gastroenterology assistants in abdominal palpation during colonoscopy, as well as to train team interaction skills for the colonoscopy team. To understand the haptic feedback forces to be simulated by the haptic device, we conducted an experiment with five participants of varying BMI. The applied forces and displacements were measured and hysteresis modeling was used to characterize the experimental data. These models were used to determine the haptic feedback forces required to simulate a BMI case in response to the real-time user interactions. The pneumatic haptic device consisted of a sphygmomanometer bladder as the haptic interface and a fuzzy controller to regulate the bladder pressure. The haptic device showed good steady state and dynamic response was adequate for simulating haptic interactions. Tracking accuracy averaged 94.2 percent within 300 ms of the reference input while the user was actively applying abdominal palpation and minor repositioning.