Prospective analysis of fluoroscopy duration during ERCP: critical determinants

Comparison of radiation-shielding curtains for endoscopic retrograde cholangiopancreatography staff

Occupational radiation exposure to the eye lens of medical staff during endoscopic retrograde cholangiopancreatography (ERCP) should be kept low so as not to exceed annual dose limits. Dose should be low to avoid tissue reactions and minimizing stochastic effects. It is known that the head and neck of the staff are exposed to more scattered radiation in an over-couch tube system than in a C-arm system (under-couch tube). However, this is only true when radiation-shielding curtains are not used. This study aimed to compare the protection radiation to the occupationally exposed worker between a lead curtain mounted on a C-arm system and an ERCP-specific lead curtain mounted on an over-couch tube system. A phantom study simulating a typical setting for ERCP procedures was conducted, and the scattered radiation dose at four staff positions were measured. It was found that scattered radiation doses were higher in the C-arm with a lead curtain than in the over-couch tube with an ERCP-specific lead curtain at all positions measured in this study. It was concluded that the over-couch tube system with an ERCP-specific lead curtain would reduce the staff eye dose by less than one-third compared to the C-arm system with a lead curtain. For the C-arm system, it is necessary to consider more effective radiation protection measures for the upper body of the staff, such as a ceiling-suspended lead screen or another novel shielding that do not interfere with procedures.

Fundamental study on diagnostic reference level quantities for endoscopic retrograde cholangiopancreatography using a C-arm fluoroscopy system

The diagnostic reference level (DRL) is an effective tool for optimising protection in medical exposures to patients. However regarding air kerma at the patient entrance reference point (Ka,r), one of the DRL quantities for endoscopic retrograde cholangiopancreatography (ERCP), manufacturers use a variety of the International Electrotechnical Commission and their own specific definitions of the reference point. The research question for this study was whetherKa,ris appropriate as a DRL quantity for ERCP. The purpose of this study was to evaluate the difference betweenKa,rand air kerma incident on the patient's skin surface (Ka,e) at the different height of the patient couch for a C-arm system. Fluoroscopy and radiography were performed using a C-arm system (Ultimax-i, Canon Medical Systems, Japan) and a over-couch tube system (CUREVISTA Open, Fujifilm Healthcare, Japan).Ka,ewas measured by an ion chamber placed on the entrance surface of the phantom. Kerma-area product (PKA) andKa,rwere measured by a built-inPKAmeter and displayed on the fluoroscopy system.Ka,edecreased whileKa,rincreased as the patient couch moved away from the focal spot. The uncertainty of theKa,e/Ka,rratio due to the different height of the patient couch was estimated to be 75%-94%.Ka,rmay not accurately representKa,e.PKAwas a robust DRL quantity that was independent of the patient couch height. We cautioned against optimising patient doses in ERCP with DRLs set in terms ofKa,rwithout considering the patient couch height of the C-arm system. Therefore, we recommend thatKa,ris an inappropriate DRL quantity in ERCP using the C-arm system.

Radiation in Gastroenterology

The benefit of radiation is immense in the field of gastroenterology. Radiation is used daily in different gastrointestinal imaging and diagnostic and therapeutic interventional procedures. Radiotherapy is one of the primary modalities of treatment of gastrointestinal malignancies. There are various modalities of radiotherapy. Radiotherapy can injure malignant cells by directly damaging DNA, RNA, proteins, and lipids and indirectly by forming free radicals. External beam radiation, internal beam radiation and radio-isotope therapy are the major ways of delivering radiation to the malignant tissue. Radiation can also cause inflammation, fibrosis, organ dysfunction, and malignancy. Patients with repeated exposure to radiation for diagnostic imaging and therapeutic procedures are at slightly increased risk of malignancy. Gastrointestinal endoscopists performing fluoroscopy-guided procedures are also at increased risk of malignancy and cataract formation. The radiological protection society recommends certain preventive and protective measures to avoid side effects of radiation. Gastrointestinal complications related to radiation therapy for oncologic processes, and exposure risks for patients and health care providers involved in diagnostic or therapeutic imaging will be discussed in this review.

Prediction model using clinical factors for radiation exposure during endoscopic retrograde cholangiopancreatography

BACKGROUND AND AIM

Endoscopic retrograde cholangiopancreatography (ERCP) requires radiation. This study aimed to assess the clinical factors influencing radiation exposure and devise a scoring model for predicting high-dose radiation exposure.

METHODS

Endoscopic retrograde cholangiopancreatography cases recorded between 2016 and 2019 in a single tertiary teaching hospital were retrospectively reviewed. A scoring model was created by bootstrap method in a derivation cohort (2016-2018) and was assessed in a validation cohort (2019).

RESULTS

Out of 4223 ERCPs, 2983 and 1240 cases were included in the derivation and validation cohorts, respectively. In the derivation cohort, 746 cases (top 25%) comprised the high-dose exposure group, and 2237 cases (bottom 75%) comprised the low-dose exposure group. Nine clinical parameters associated with high-dose exposure were male, pancreatic sphincterotomy, balloon dilatation, biliary or pancreatic drainage, procedures with contrast dye, endoscopist, in-hospital ERCP, and spot image. Stone removal was included by bootstrap analysis. As presented in a nomogram, the weight score of each variable was as follows: male, 1; pancreatic sphincterotomy, 3; balloon dilatation, 7; stone removal, 3; biliary or pancreatic drainage, 5; procedures with contrast dye, 1; endoscopist B, 4; endoscopist C, 5; in-hospital procedure, 3; and spot image, 3. A total score ≥ 15 suggested a high-dose radiation exposure. The sensitivity and specificity of the model for high-dose exposure were 0.562 and 0.813, respectively. In the validation cohort, the model showed reasonable predictability.

CONCLUSIONS

Various factors were associated with radiation exposure. The simple scoring system in this study could guide endoscopists in predicting the risk of high-dose radiation exposure.

Reduced Fluoroscopy Time With Physician-Controlled Fluoroscopy During Endoscopic Retrograde Cholangiopancreatography: A Community Hospital Experience

Background and objective

Fluoroscopy during endoscopic retrograde cholangiopancreatography (ERCP) is associated with radiation exposure and related health risks. Either the physician or the radiology technologist can activate fluoroscopy during ERCP. The aim of this study was to determine if physician-controlled fluoroscopy is associated with decreased fluoroscopy time, which may correspond to less radiation exposure to patients and staff. 

Methods

We conducted a single-center, retrospective study; data were collected on ERCP performed using physician-controlled and technologist-controlled fluoroscopy. Fluoroscopy time, procedure complexity level, and Stanford Fluoroscopy Score were compared between the two groups.

Results

The median fluoroscopy time significantly differed between the two groups with 108 seconds for physician-controlled and 146 seconds for technologist-controlled procedures (p=0.004). The ratio of median fluoroscopy time to procedure complexity level was significantly lower in the physician-controlled group at 73.0 seconds compared to 97.0 seconds in the technologist-controlled group (p=0.002). The ratio of median fluoroscopy time to Stanford Fluoroscopy Score was 25.5 seconds in the physician-controlled group compared to 39.3 seconds in the technologist-controlled group, which was also statistically significant (p<0.001). A subgroup analysis of physicians with advanced training in ERCP also showed a significantly reduced median fluoroscopy time to Stanford Fluoroscopy Complexity Score ratio: 25.5 seconds for physician-controlled versus 35.0 seconds for technologist-controlled (p=0.001).

Conclusion

The ERCP technique with physician-controlled fluoroscopy may be associated with shorter fluoroscopy time. This may correspond to decreased radiation exposure to patients compared to radiology technologist-controlled fluoroscopy. Further investigations with larger, prospective studies are warranted.

Multicenter database registry for endoscopic retrograde cholangiopancreatography: Japan Endoscopic Database Project

BACKGROUND AND AIM

Few studies have reported on a national, population-based endoscopic retrograde cholangiopancreatography (ERCP) database. Hence, in 2015, we established a multicenter ERCP database registry, the Japan Endoscopic Database (JED) Project in preparation for a nationwide endoscopic database. The objective the present study was to evaluate this registry before the establishment of a nationwide endoscopic database.

METHODS

From 1 January 2015 to 31 March 2017, we collected and analyzed the ERCP data of all patients who underwent ERCP in four participating centers in the JED Project based on the JED protocol.

RESULTS

Four centers carried out 4104 ERCP on 2173 patients. Data entry of ERCP information (age, 100%; gender, 100%; American Society of Anesthesiologists Physical Status Classification System, 74.5%; scope, 92.7%; time to ERCP, 100%; antithrombotic drug information, 55.0%; primary selective common bile duct [CBD] cannulation methods, 73.0%; number of attempts at primary selective CBD cannulation, 67.6%; overall selective CBD cannulation methods, 68.9%; ERCP procedure time, 66.3%; fluoroscopy time, 65.1%; adverse events, 74.9%; serum amylase levels 1 day post-ERCP, 36.5%) was accurately extracted from the four centers. Success rate of CBD cannulation by level of ERCP difficulty was 98.5%, 99.0%, and 96.4% in grades 1, 2, and 3, respectively. Complication rate by overall selective CBD cannulation method was 5.6%, 7.6%, and 10.5% in the contrast-assisted technique, guidewire-assisted technique, and cross-over method, respectively.

CONCLUSION

Data from this evaluation of the JED Project, a multicenter ERCP database registry, suggest the feasibility of establishing a nationwide ERCP database and its challenges.

Radiation exposure during endoscopic retrograde cholangiopancreatography according to clinical determinants

This study aimed to analyze the dose of radiation to which the physician is exposed during endoscopic retrograde cholangiopancreatography (ERCP) and to identify predictive factors of radiation exposure during the procedure. Furthermore, we evaluated the patient characteristics and procedural factors associated with prolonged fluoroscopy time (FT).A cross-sectional retrospective analysis of 780 ERCPs performed at a tertiary academic hospital over a 2-year period was conducted. The primary outcome was radiation exposure during ERCP as determined by FT; additionally, the association between variables and radiation exposure was determined. Moreover, we evaluated their correlations with age, sex, body mass index (BMI), diagnosis, duration of procedure, procedure name, and procedure complexity.According to the analysis of the 780 ERCPs performed in 2 years, the mean FT was 5.07 minutes (95% confidence interval [CI], 4.87-5.26). The mean radiation durations were as follows: cholelithiasis, 5.76 minutes (95% CI, 4.75-6.80); malignant biliary obstruction, 6.13 minutes (95% CI, 5.91-6.35); pancreatic disease, 5.28 minutes (95% CI, 4.45-6.28); and benign biliary stricture, 5.32 minutes (95% CI, 5.02-5.94). Significant differences affecting fluoroscopy duration between the 2 endoscopists were not observed in the present study. Multivariate analysis revealed that prolonged fluoroscopy duration was related to specific characteristics, including higher BMI (BMI >27.5 kg/m) (+4.1 minutes; 95% CI, 2.56-5.63), mechanical lithotripsy (+4.85 minutes; 95% CI, 0.45-9.25), needle-knife use (+4.5 minutes; 95% CI, 2.15-6.86), and malignant biliary obstruction (+2.34 minutes; 95% CI, 0.15-4.53).ERCPs are associated with significantly higher radiation exposure of patients on the specific procedure. Endoscopists should be aware of the determining factors, including patients with obesity, who underwent mechanical lithotripsy, who had malignant biliary obstruction, and who underwent a procedure using a needle knife, that affect FT during ERCP.

Preventing Harm From Fluoroscopically Guided Interventional Procedures With a Risk-Based Analysis Approach

PURPOSE

Fluoroscopically guided interventional (FGI) procedures often have lower complication rates compared with alternative surgical procedures, providing an option for patients with a high risk of perioperative mortality. Although severe radiation injuries are rare, patients receiving peak skin doses exceeding 3 Gy can suffer from radiation-induced tissue injuries, ranging from transient erythema to nonhealing wounds. As these iatrogenic injuries may manifest weeks to months postprocedure, proper diagnosis and timely medical intervention are less likely. Clinically, the lack of situational awareness for monitoring air kerma continues to be a challenge despite the recommendations of numerous organizations on ways to achieve fluoroscopy safety. For patient safety efforts, this study aimed to identify and mitigate systematic gaps associated with potentially high-radiation dose fluoroscopic procedures in US Department of Veterans Affairs (VA) and non-VA medical institutions.

METHODS

In this study, a multi-institutional team utilized Healthcare Failure Mode and Effect Analysis (HFMEA) on an example implantable cardioverter defibrillator lead extraction procedure.

RESULTS

With this approach, 29 interventions were devised and prioritized by feasibility, cost-effectiveness, and expected clinical impact. Five of the 29 interventions were recommended for immediate implementation or piloting.

CONCLUSIONS

This work demonstrates the application of formal risk-based analysis techniques in FGI procedures. These high priority interventions may be valuable for other facilities to consider when performing potentially high-radiation dose procedures and conducting risk-benefit analyses. Formal risk analysis techniques such as the HFMEA process are recommended for other facilities to use to improve safety for their high-risk procedures.

The emerging role of non-radiation endoscopic management of biliary tract disorders

Endoscopic retrograde cholangiopancreatography (ERCP) has evolved from a diagnostic and therapeutic technique into a therapeutic-centered modality for managing biliary disorders. Despite its many therapeutic benefits, radiation exposure from ERCP fluoroscopy is of concern and should be minimized as much as possible. Although the use of personal equipment offers significant protection against radiation, attention has been given to the development of non-radiation-based ERCP techniques. To this end, digital cholangioscopy and endoscopic ultrasound-assisted ERCP have emerged as alternatives to standard ERCP. Both techniques have sufficient feasibility and potential diagnostic accuracy to eliminate the need for fluoroscopy. Here we discuss the advances in non-radiation ERCP techniques and their role in the management of biliary stones.

A pilot single-center prospective randomized trial to assess the short-term effect of a flashing warning light on reducing fluoroscopy time and radiation exposure during ERCP

BACKGROUND AND AIMS

ERCP has the risk of exposure to ionizing radiation. Performers may unconsciously increase fluoroscopy time (FT) because of a lack of radiation protection awareness. This study investigates whether a flashing warning light adopted as a behavioral intervention for performers reduces FT and radiation exposure during ERCP.

METHODS

We conducted a prospective randomized trial of 200 therapeutic ERCPs. A flashing warning light was placed on top of the endoscopy monitor. Cases were consecutively enrolled and randomly assigned to 2 groups in a 1:1 ratio. In the warning light group, the light was on when the fluoroscopy foot pedal was depressed; in the control group, the light was off. Fluoroscopy and procedure-related data were recorded.

RESULTS

The median FT and dose-area product (DAP) for the warning light group versus the control group were 142.5 seconds versus 175.0 seconds (P = .045) and 856.8 μGy∙m² versus 1054.4 μGy∙m² (P = .043). In a multivariable analysis, the use of the warning light was found to reduce FT by 15.4% (-27.0 seconds; P = .042). DAP reduction because of the decreased FT was 15.2% (160.3 μGy∙m²). The reduction in patient effective dose per case was .42 mSv, equivalent to 21 chest radiographs. No adverse events or interference with the procedures because of the warning light were noted.

CONCLUSIONS

The use of a flashing warning light is a feasible way to reduce FT and radiation exposure during ERCP. (Clinical trial registration number: ChiCTR-IPR-14005349.).

Location of Disease on Imaging may Predict Radiation Exposure During Endoscopic Retrograde Cholangiopancreatography

Endoscopic retrograde cholangiopancreatography (ERCP) is performed for various diseases. The aim of this study is to evaluate the difference of dose-area product (DAP) during the ERCP procedures according to location of the lesion. We performed a retrospective study of consecutive 217 therapeutic ERCP examinations performed between November 2014 and April 2015 at a tertiary care center. ERCP procedures divided into two groups according to location of the lesion identified on imaging: lesions in the common hepatic duct (CHD) or the common bile duct (CBD) and lesions in the hepatic hilum or the intrahepatic duct (IHD). The mean DAP of the hilum-IHD group (48.7 Gy cm2) was significantly higher than that of the CBD-CHD group (34.9 Gy cm2) (P = 0.003). Radiation exposure during ERCP was significantly different according to location of bile duct lesion.

Occupation-associated health hazards for the gastroenterologist/endoscopist

Advances in the field of endoscopy have allowed gastroenterologists to obtain detailed imaging of anatomical structures and to treat gastrointestinal diseases with endoscopic therapies. However, these technological developments have exposed endoscopists and staff to hazards such as musculoskeletal injuries, exposure to infectious agents, and ionizing radiation. We aimed to review the occupational hazards for the gastroenterologist and endoscopist. Using PubMed, Medline, Medscape, and Google Scholar, we identified peer-reviewed articles with the keywords “occupational hazards,” “health hazards,” “occupational health hazards,” “endoscopy,” “gastroenterologist,” “infectious agents,” “musculoskeletal injuries,” and “radiation.” Strategies for reducing exposure to infectious agents, radiation, and the risk of musculoskeletal injuries related to gastroenterology include compliance with established standard measures, the use of thyroid shields and radioprotective eyewear, and ergonomic practices. We conclude that educating endoscopic personnel and trainees in these practices, in addition to further research in these areas, will likely lead to the development of more efficient and user-friendly workspaces that are safer for patients and personnel.

Patient radiation dose and fluoroscopy time during ERCP: a single-center, retrospective study of influencing factors

OBJECTIVES

Recently, both the number and the complexity with associated increased technical difficulty of therapeutic ERCP procedures have significantly increased resulting in longer procedural and fluoroscopy times. During ERCP, the patient is exposed to ionizing radiation and the consequent radiation dose depends on multiple factors. The aim of this study was to identify factors affecting fluoroscopy time and radiation dose in patients undergoing ERCP.

MATERIALS AND METHODS

Data related to patient demographics, procedural characteristics and radiation exposure in ERCP procedures (n = 638) performed between August 2013 and August 2015 was retrospectively reviewed and analyzed. Statistically significant factors identified by univariate analyses were included in multivariate analysis with fluoroscopy time (FT) and dose area product (DAP) as dependent variables. Effective dose (ED) was estimated from DAP measurements using conversion coefficient.

RESULTS

The factors independently associated with increased DAP during ERCP were age, gender, radiographer, complexity level of ERCP, cannulation difficulty grade, bile duct injury and biliary stent placement. In multivariate analysis the endoscopist, the complexity level of ERCP, cannulation difficulty grade, pancreatic duct leakage, bile duct dilatation and brushing were identified as predictors for a longer FT. The mean DAP, FT, number of acquired images and ED for all ERCP procedures were 2.33 Gy·cm², 1.84 min, 3 and 0.61 mSv, respectively.

CONCLUSIONS

Multiple factors had an effect on DAP and FT in ERCP. The awareness of these factors may help to predict possible prolonged procedures causing a higher radiation dose to the patient and thus facilitate the use of appropriate precautions.

Patient Radiation Doses in Therapeutic Endoscopic Retrograde Cholangiopancreatography in Patras and the Key Role of the Operator

The patient radiation doses, in conjunction with the operator experience, in therapeutic endoscopic retrograde cholangiopancreatography (ERCP) procedures, performed in our hospital, were obtained. Ninety-six patients participated in the study and were divided into 3 groups, based on the operator experience. The dosemetric indices, fluoroscopy time (FT), cumulative dose (Ka,r) and air kerma-area product (PKA), were collected. For the total and weight banding group the third quartile values of the distribution of FT, Ka,r and PKA were 2.90 and 2.92 min, 6.89 and 6.93 mGy and 1.84 and 1.85 Gycm2, respectively, and were comparative or significantly lower than the corresponding values previously reported. Taking as a criterion the operator, the differences in the patient radiation doses were statistically significant, with the highest dose recorded for the operator of the lowest experience degree. The values obtained could contribute in establishing local and national diagnostic reference levels and in optimising ERCP procedure.

OPTIMISATION OF PATIENT DOSE AND IMAGE QUALITY IN ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY: A PHANTOM-BASED EVALUATION

A phantom-based study is presented aiming to optimise patient dose and image quality (IQ) in endoscopic retrograde cholangiopancreatography procedures, utilising a fluoroscopy system equipped with a flat panel detector. The patient thickness was simulated with various polymethyl methacrylate slabs, whilst IQ was evaluated using the Leeds test object. The main factors evaluated were phantom thickness, distance between phantom and detector, field of view and pulse rate. For all these factors, the dosemetric indices, entrance surface air kerma (ESAK) rate and ESAK per pulse, as well as the IQ parameters, signal-to-noise ratio and high contrast spatial resolution, were measured. Based on these measurements, the figure of merit (FOM) was estimated. The FOM and ESAK rate values indicated the optimum combination of the factors evaluated which could provide adequate clinical information, assuring minimum patient dose.

A simple ergonomic measure reduces fluoroscopy time during ERCP: A multivariate analysis

Background and study aims Endoscopic retrograde cholangiopancreatgraphy (ERCP) carries a radiation risk to patients undergoing the procedure and the team performing it. Fluoroscopy time (FT) has been shown to have a linear relationship with radiation exposure during ERCP. Recent modifications to our ERCP suite design were felt to impact fluoroscopy time and ergonomics. This multivariate analysis was therefore undertaken to investigate these effects, and to identify and validate various clinical, procedural and ergonomic factors influencing the total fluoroscopy time during ERCP. This would better assist clinicians with predicting prolonged fluoroscopic durations and to undertake relevant precautions accordingly. Patients and methods A retrospective analysis of 299 ERCPs performed by 4 endoscopists over an 18-month period, at a single tertiary care center was conducted. All inpatients/outpatients (121 males, 178 females) undergoing ERCP for any clinical indication from January 2012 to June 2013 in the chosen ERCP suite were included in the study. Various predetermined clinical, procedural and ergonomic factors were obtained via chart review. Univariate analyses identified factors to be included in the multivariate regression model with FT as the dependent variable. Results Bringing the endoscopy and fluoroscopy screens next to each other was associated with a significantly lesser FT than when the screens were separated further (-1.4 min, P = 0.026). Other significant factors associated with a prolonged FT included having a prior ERCP (+ 1.4 min, P = 0.031), and more difficult procedures (+ 4.2 min for each level of difficulty, P < 0.001). ERCPs performed by high-volume endoscopists used lesser FT vs. low-volume endoscopists (-1.82, P = 0.015). Conclusions Our study has identified and validated various factors that affect the total fluoroscopy time during ERCP. This is the first study to show that decreasing the distance between the endoscopy and fluoroscopy screens in the ERCP suite significantly reduces the total fluoroscopy time, and therefore radiation exposure to patients and staff involved in the procedure.

THE IMPACT OF X-RAY UNIT TYPE USED FOR ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY PROCEDURES ON PATIENT DOSES

To investigate whether the X-ray unit type used for interventional endoscopic retrograde cholangiopancreatography (ERCP) procedures may affect patient radiation doses. A total of 471 ERCP procedures performed in 4 hospitals with 4 types of X-ray units were studied. Kerma-area product (KAP), fluoroscopy time (T) and total number of radiographs acquired (F) were recorded. KAP, T and F values exhibited a great variation, ranging from 0.1 to 130.2 Gy cm² (mean 16 Gy cm²), 0.13 to 33.7 min (mean 5.4 min) and 0 to 26 radiographs (mean 3.5), respectively. The respective mean values for the four types of X-ray units that were investigated were as follows: KAP: 17.4, 12.5, 5.6 and 36.3 Gy cm², T: 4.7, 5.2, 3.8 and 11.5 min and F: 1.7, 7.4, 1.9 and 4.6 radiographs. The type of the X-ray unit seems to significantly affect patient radiation dose, with the C-arm delivering the lowest and the angiography unit the highest patient doses.

No reduction of radiation dose following the introduction of dose-area product measurement in endoscopic retrograde cholangiopancreatography

BACKGROUND

During radiological examinations such as endoscopic retrograde cholangiopancreatography (ERCP), it is recommended to record the dose-area product (DAP) to reduce the patient's and the physician's exposure to ionizing radiation. However, the effect of DAP measurement on the total radiation dose in ERCP procedures has never been assessed.

OBJECTIVES

This study evaluated radiation dose use in ERCP procedures following the introduction of DAP measurement in the endoscopy unit. Also, patient-related, endoscopist-related and procedure-related factors associated with high DAP values were assessed.

MATERIALS AND METHODS

All consecutive ERCPs from January 2008 to March 2011 were retrospectively reviewed. The DAP values and demographic-specific and disease-specific parameters were obtained from patient files and ERCP reports.

RESULTS

A total of 279 ERCPs was analysed. The median DAP was 1907 cGy cm (range 316-7981). There was no significant decrease in the total radiation dose used in ERCPs following the installation of the DAP-meter in the endoscopy unit. Variables associated with significantly higher DAP values were precut papillotomy [odds ratio (OR) 2.44], hydrostatic balloon dilation (OR 3.56), stone extraction with a basket (OR 5.27) and procedures performed at the weekend (OR 6.43).

CONCLUSION

The introduction of DAP measurement during ERCP did not result in a significant decrease in the total radiation dose. Several risk factors associated with a high radiation dose during ERCP procedures were identified, of which precut papillotomy and procedures performed during the weekend have not been described before in the literature. These factors enable endoscopists to more accurately identify patients at an increased risk of high radiation exposure.

Minimizing Radiation Exposure During ERCP by Avoiding Live or Continuous Fluoroscopy

GOALS

The aim of this study was to assess the cumulative radiation exposure incurred by patients when using single-frame fluoroscopy.

BACKGROUND

Single-frame fluoroscopy is a technique that can be used instead of pulsed fluoroscopy or continuous live fluoroscopy to minimize radiation exposure during endoscopic retrograde cholangiopancreatography (ERCP).

STUDY

We retrospectively reviewed ERCPs performed at our academic medical center. We recorded fluoroscopy time (FT, minutes), total radiation dose (mGy), dose area product (DAP, Gy cm²), and effective dose (ED, mSv). ERCP degree of difficulty was graded based on procedure complexity level.

RESULTS

There were 400 ERCP procedures performed on 210 patients, 32 ERCPs were unsuccessful. The mean FT for all procedures was 1.57 minutes (median, 1.2 min); the mean FT for complexity score 1 procedures (0.78 min) was significantly shorter than for all other procedures (P<0.0001). The mean total radiation dose delivered for all procedures was 23.02 mGy (median, 14.95 mGy). The total radiation dose for complexity score 1 procedures (13.15 mGy) was significantly lower than for all other complexity scores (P<0.0001). The mean total DAP was 3.62 Gy cm² and the mean ED was 0.94 mSv. Procedure complexity score 1 DAP (2.1 Gy cm²) and ED (0.55 mSv) were significantly lower than for all other procedures (P<0.0001 for both). There was no statistically significant difference in these parameters when comparing successful and unsuccessful procedures.

CONCLUSIONS

Successful ERCP can be performed using single-frame fluoroscopy only. Our results demonstrate lower radiation exposure using this technique than what is reported in the literature.

Anatomical Location of Pathology Is Predictive of Prolonged Fluoroscopy Time During ERCP: A Multicenter American Study

BACKGROUND

Different factors have been associated with prolonged fluoroscopy time (FT) during endoscopic retrograde cholangiopancreatography (ERCP).

AIM

We hypothesize that FT depends on both the anatomical location of the pathology managed during ERCP and the complexity of the ERCP.

METHODS

Three centers participated in a retrospective multi-center cohort study. Data on patient demographics, ERCP complexity, and the location of pathology were collected. The relationships between FT and the location of pathology, ERCP complexity, patient demographics, and ERCP maneuvers, respectively, were analyzed. Prolonged FT was defined as a FT > 10 min.

RESULTS

A total of 442 cases underwent ERCP in three different centers (301 cases, 76 cases, and 65 cases in centers A, B, and C, respectively) by six endoscopists. The median FT for all cases was 282 (range 8-3,516) s. Mean FT increased progressively according to anatomical location in the order extrahepatic cases {n = 298; mean FT 292 [95 % confidence interval (CI) 263-322] s}, pancreatic cases [n = 27; mean FT 359 (95 % CI 200-517) s], and intrahepatic cases [n = 117; mean FT 736 s (95 % CI 635-836) s]. Mean FT increased progressively with the complexity scale, with mean FT for Grade I, 218 (95 % CI 138-299) s; Grade II, 295 (95 % 261-329) s; Grade III, 586 (95 % CI 508-663) s; Grade IV, 636 (95 % CI 437-834) s. Multivariable analysis confirmed that prolonged FT was independently associated with anatomical location of the targeted pathology during ERCP-but not with ERCP complexity and endoscopy center.

CONCLUSION

Prolonged FT during ERCP is associated most strongly with intrahepatic cases. FT can be used most effectively as a quality measure if it is stratified according to presence or absence of intrahepatic cases.

A double-blind, randomized, sham-controlled trial of the effect of a radiation-attenuating drape on radiation exposure to endoscopy staff during ERCP

OBJECTIVES

Endoscopic retrograde cholangiopancreatography (ERCP) is associated with radiation exposure to the endoscopist and staff that may be significant in high-volume centers. We investigated whether a radiation-attenuating drape over the fluoroscopy image intensifier reduces radiation exposure during ERCP.

METHODS

We performed a prospective, randomized, double-blind trial of 100 therapeutic ERCPs at a tertiary-care university center. Procedures were randomly assigned to groups receiving lead-free radiation-attenuating drapes (n=50) or identical sham drapes (n=50). The drapes were suspended around the fluoroscopy image intensifier during ERCP. The primary end point was the effective dose of radiation measured at the endoscopist's eye and neck, and at the assisting nurse's neck. The cumulative annual radiation exposure was also estimated.

RESULTS

Fluoroscopy time, absorbed radiation dose, and dose area product were similar in the study groups. Mean effective dose for sham vs. radiation-attenuating drape was 0.21±0.27 vs. 0.02±0.02 mSv at the endoscopist's eye, 0.35±0.44 vs. 0.03±0.03 mSv at the endoscopist's neck, and 0.27±0.34 vs. 0.02±0.02 mSv at the nurse's neck (P<0.0001 for all comparisons). The relative risk reduction in radiation was 90%, 91%, and 93% at the three sites. At a high-volume center in which an endoscopist performs 500 therapeutic ERCPs per year, the estimated cumulative annual effective dose at the endoscopist's eye level is 126 mSv with conventional protection and 12 mSv with a radiation-attenuating drape, with the recommended limit being 20 mSv.

CONCLUSIONS

The addition of a radiation-attenuating drape around the image intensifier during ERCP significantly decreases radiation exposure to endoscopists and staff by ∼90%.

Measures of patient radiation exposure during endoscopic retrograde cholangiography: Beyond fluoroscopy time

AIM: To determine whether fluoroscope time is a good predictor of patient radiation exposure during endoscopic retrograde cholangiopancreatography.

METHODS: This is a prospective observational study of consecutive patients undergoing endoscopic retrograde cholangiopancreatography in a tertiary care setting. Data related to radiation exposure were collected. The following measures were obtained: Fluoroscopy time (FT), dose area product (DAP) and dose at reference point (DOSERP). Coefficients of determination were calculated to analyze the correlation between FT, DAP and DOSRP. Agreement between FT and DAP/DOSRP was assessed using Bland Altman plots.

RESULTS: Four hundred sixty-three data sets were obtained. Fluoroscopy time average was 7.3 min. Fluoroscopy related radiation accounted for 86% of the total DAP while acquisition films related radiation accounted for 14% of the DAP. For any given FT there are wide ranges of DAP and DOSERP and the variability in both increases as fluoroscopy time increases. The coefficient of determination (R²) on the non transformed data for DAP and DOSERP versus FT were respectively 0.416 and 0.554. While fluoroscopy use was the largest contributor to patient radiation exposure during endoscopic retrograde cholangiography (ERCP), there is a wide variability in DAP and DOSERP that is not accounted for by FT. DAP and DOSERP increase in variability as FT increases. This translates into poor accuracy of FT in predicting DAP and DOSERP at higher radiation doses.

CONCLUSION: DAP and DOSERP in addition to FT should be adopted as new ERCP quality measures to estimate patient radiation exposure.

Radiation exposure to patients during ERCP is significantly higher with low-volume endoscopists

BACKGROUND

Patients are exposed to radiation during ERCP, and this may increase their lifetime risk of the development of cancer and other deleterious radiation effects.

OBJECTIVE

To evaluate the association between the endoscopist's ERCP volume and the patient radiation dose during ERCP.

DESIGN

Single-center, retrospective study.

SETTING

Tertiary referral center.

PATIENTS AND INTERVENTIONS

A total of 197 patients undergoing 331 ERCPs.

MAIN OUTCOME MEASUREMENTS

Patient radiation exposure parameters including fluoroscopy time, total radiation dose, dose area product, and effective dose for all ERCPs performed at our academic medical center by 2 high-volume endoscopists (HVEs) (≥200 ERCPs/year) and 7 low-volume endoscopists (LVEs). Radiation exposure for each ERCP was adjusted against a validated procedure complexity scale and the Stanford Fluoroscopy Complexity Score, which was created based on the numbers of interventions that would mandate additional radiation exposure.

RESULTS

ERCPs performed by LVEs were associated with a significantly higher median total radiation dose (98.30 mGy vs 74.13 mGy), dose area product (13.98 Gy-cm(2) vs 8.8 Gy-cm(2)), and effective dose (3.63 mSv vs 2.28 mSv), despite lower median Stanford Fluoroscopy Complexity Scores (3.0 vs 6.0) compared with HVEs. No significant difference was noted in median fluoroscopy time (4.0 minutes vs 3.30 minutes) between LVEs and HVEs.

LIMITATIONS

Retrospective, single-center study at a tertiary referral center.

CONCLUSION

ERCPs performed by LVEs are associated with significantly higher radiation exposure to patients compared with those performed by HVEs despite the fact that procedures performed by HVEs are of greater complexity.

Radiation exposure in gastroenterology: improving patient and staff protection

Medical imaging involving the use of ionizing radiation has brought enormous benefits to society and patients. In the past several decades, exposure to medical radiation has increased markedly, driven primarily by the use of computed tomography. Ionizing radiation has been linked to carcinogenesis. Whether low-dose medical radiation exposure will result in the development of malignancy is uncertain. This paper reviews the current evidence for such risk, and aims to inform the gastroenterologist of dosages of radiation associated with commonly ordered procedures and diagnostic tests in clinical practice. The use of medical radiation must always be justified and must enable patients to be exposed at the lowest reasonable dose. Recommendations provided herein for minimizing radiation exposure are based on currently available evidence and Working Party expert consensus.

Predicting native papilla biliary cannulation success using a multinational Endoscopic Retrograde Cholangiopancreatography (ERCP) Quality Network

Background

Success in deep biliary cannulation via native ampullae of Vater is an accepted measure of competence in ERCP training and practice, yet prior studies focused on predicting adverse events alone, rather than success. Our aim is to determine factors associated with deep biliary cannulation success, with/ without precut sphincterotomy.

Methods

The ERCP Quality Network is a unique prospective database of over 10,000 procedures by over 80 endoscopists over several countries. After data cleaning, and eliminating previously stented or cut papillae, two multilevel fixed effect multivariate models were used to control for clustering within physicians, to predict biliary cannulation success, with and without allowing “precut” to assist an initially failed cannulation.

Results

13018 ERCPs were performed by 85 endoscopists (March 2007 - May 2011). Conventional (without precut) and overall cannulation rates were 89.8% and 95.6%, respectively. Precut was performed in 876 (6.7%). Conventional success was more likely in outpatients (OR 1.21), but less likely in complex contexts (OR 0.59), sicker patients (ASA grade (II, III/V: OR 0.81, 0.77)), teaching cases (OR 0.53), and certain indications (strictures, active pancreatitis). Overall cannulation success (some precut-assisted) was more likely with higher volume endoscopists (> 239/year: OR 2.79), more efficient fluoroscopy practices (OR 1.72), and lower with moderate (versus deeper) sedation (OR 0.67).

Conclusion

Biliary cannulation success appears influenced by both patient and practitioner factors. Patient- and case-specific factors have greater impact on conventional (precut-free) cannulation success, but volume influences ultimate success; both may be used to select appropriate cases and can help guide credentialing policies.

Impact of periampullary diverticula on the outcome and fluoroscopy time in endoscopic retrograde cholangiopancreatography

BACKGROUND

It is unclear whether the presence of periampullary diverticula (PAD) affects technical success and complication rates during endoscopic retrograde cholangiopancreatography (ERCP). Moreover, the impact of PAD on fluoroscopy duration is still unknown. The present study aimed to investigate the success rate and difficulty of common bile duct (CBD) cannulation, post-procedure complications and fluoroscopy duration in patients with and without PAD.

METHODS

Patients from January 2008 to December 2010 with PAD (group A) and without PAD (group B) and similar indications for therapeutic ERCP were prospectively compared. The comparison included patient characteristics, findings of ERCP, and details of procedure and fluoroscopy time. The influence of papilla's location with respect to the diverticulum on procedure was also investigated.

RESULTS

A total of 428 consecutive patients who had undergone therapeutic ERCP for similar indications were divided in two groups according to the presence (group A, 107 patients) or absence (group B, 321 patients) of PAD. The mean age and ASA score of the patients with PAD were significantly higher than those patients without PAD. The main indication was choledocholithiasis. Successful final CBD cannulation was achieved in 97.20% of the patients in group A vs 99.69% in group B (P=0.05). CBD diameter, number of stones and the largest stone size were significantly higher in group A than group B (P<0.001). Complete clearance of the CBD after the first attempt was achieved in 85.86% and 94.75% of the patients in groups A and B, respectively (P=0.03). In both groups, the time needed to complete the procedure and fluoroscopy time was significantly longer in patients with PAD (22.87 vs 18.99 minutes, P<0.001; 76.51 vs 47.42 seconds, P<0.001). There was no significant difference between the two groups in the complication rate. The type of papilla's location with respect to the diverticulum did not influence the total cannulation rate and post-procedure complications.

CONCLUSION

The presence of a PAD does not affect the success rate and complications of therapeutic ERCP in expert hands; however, the fluoroscopy time is significantly longer in patients with PAD.

Recording ERCP fluoroscopy metrics using a multinational quality network: establishing benchmarks and examining time-related improvements

OBJECTIVES

We aimed to establish benchmarks for fluoroscopy time (FT) in endoscopic retrograde cholangiopancreatography (ERCP) and assess the effect of physician practice networking on time trends.

METHODS

Data from the ERCP Quality Network were used to assess practice variability in FT and establish case- and provider-level benchmarks of the first 200 cases for providers entering more than 100 cases. Trends in FT and high FT, by 50-patient groupings, were assessed by multilevel multivariate linear and logistic regression models.

RESULTS

Median FT was 2.9 minutes, averaging 16% of procedure time. Ninetieth percentiles for the 57 eligible providers were 10 minutes and 22% (n = 9, 185 ERCP). Every 50 cases entered was associated with lower FT. In multivariate analysis, more cases entered, higher lifetime and annual volumes, lower difficulty grade, and manometry had lower FTs; academics, trainee involvement, various therapeutics, and failed cannulation had higher FTs.

CONCLUSIONS

FT is highly variable, and many provider and case factors predict FT. FT benchmarks are now available. Self-review of one's case FT might decrease FT.

A review of current disinfectants for gastrointestinal endoscopic reprocessing

Gastrointestinal endoscopy is gaining popularity for diagnostic and therapeutic purposes. However, concerns over endoscope-related nosocomial infections are increasing, together with interest by the general public in safe and efficient endoscopy. For this reason, reprocessing the gastrointestinal endoscope is an important step for effective performance of endoscopy. Disinfectants are essential to the endoscope reprocessing procedure. Before selecting an appropriate disinfectant, their characteristics, limitations and means of use must be fully understood. Herein, we review the characteristics of several currently available disinfectants, including their uses, potency, advantages, and disadvantages. Most disinfectants can be used to reprocess gastrointestinal endoscopes if the manufacturer's guidelines are followed. The selection and use of a suitable disinfectant depends on the individual circumstances of each endoscopy suite.

The impact of endoscopic retrograde cholangiopancreatography education on radiation exposure to experienced endoscopist: 'trainee effect'

BACKGROUND

Endoscopic retrograde cholangiopancreatography(ERCP), as with other fluoroscopic procedures, carries the risk of exposure of staff to radiation. However, over the last two decades, only a few studies have investigated this risk.

OBJECTIVE

The aim of this work was to evaluate the dose of radiation exposure to staff participating in ERCP procedures in a busy teaching hospital that performs more than 1,850 procedures annually.

METHODS

The entire ERCP staff consisted of the experienced endoscopist, the assistant, and two nurses who were responsible for monitoring patients as well as keeping their heads in position during the procedure. RAD DOSE NEB.226 dosimeters, which were provided by the Turkish Atomic Energy Authority, were used for this study.

RESULTS

Data on 110 consecutive therapeutic ERCP procedures was recorded. The mean fluoroscopy time was 5.65 ± 4.71 min. The mean fluoroscopy time of the 61 procedures performed by an experienced endoscopist alone was 5.41 ± 4.65 min, whereas the mean fluoroscopy time for the 49 procedures during which an assistant was involved was 5.94 ± 4.81 min (p = 0.56). In terms of median dose of ionizing radiation exposure to the eyes, the dose measurement per procedure in which the primary endoscopist participated alone was 72 microsievert (μSv), compared to 92 μSv when an assistant took part in theproceedings. Considering that the recommended annual equivalent dose limit to the lens of the eye is 150 mSv, by performing 1,850 procedures annually, the primary endoscopist exceeds this limit.

CONCLUSIONS

Based on our results, taking into consideration the heavy workload in our hospital, it would seem that more experienced endoscopists are required to help provide training in ERCP, and that the use of lead acrylic goggles is required to decrease radiation exposure to the eyes.

Retrospective analysis of radiation exposure during endoscopic retrograde cholagiopancreatography: critical determinants

BACKGROUND

Fluoroscopy during endoscopic retrograde cholangiopancreatography (ERCP) has a logarithmic relationship with radiation exposure, and carries a known risk of radiation exposure to patients and staff. Factors associated with prolonged fluoroscopy duration have not been well delineated.

OBJECTIVES

To determine the specific patient, physician and procedural factors that affect fluoroscopy duration.

METHODS

A retrospective analysis of 1071 ERCPs performed at two tertiary care referral hospitals over an 18-month period was conducted. Patient, physician and procedural variables were recorded at the time of the procedure.

RESULTS

The mean duration of 969 fluoroscopy procedures was 4.66 min (95% CI 4.38 to 4.93). Multivariable analysis showed that the specific patient factors associated with prolonged fluoroscopy duration included age and diagnosis (both P<0.0001). The endoscopist was found to play an important role in the duration of fluoroscopy (ie, all endoscopists studied had a mean fluoroscopy duration significantly different from the reference endoscopist). In addition, the following procedural variables were found to be significant: number of procedures, basket use, biopsies, papillotomy (all P<0.0001) and use of a tritome (P=0.004). Mean fluoroscopy duration (in minutes) with 95% CIs for different diagnoses were as follows: common bile duct stones (n=443) 5.12 (3.05 to 4.07); benign biliary strictures (n=135) 3.94 (3.26 to 4.63); malignant biliary strictures (n=124) 5.82 (4.80 to 6.85); chronic pancreatitis (n=49) 4.53 (3.44 to 5.63); bile leak (n=26) 3.67 (2.23 to 5.09); and ampullary mass (n=11) 3.88 (1.28 to 6.48). When no pathology was found (n=195), the mean fluoroscopy time was 3.56 min (95% CI 3.05 to 4.07). Comparison using t tests determined that the only two diagnoses for which fluoroscopy duration was significantly different from the reference diagnosis of 'no pathology found' were common bile duct stones (P<0.0001) and malignant strictures (P<0.0001).

CONCLUSIONS

Factors that significantly affected fluoroscopy duration included age, diagnosis, endoscopist, and the number and nature of procedures performed. Elderly patients with biliary stones or a malignant stricture were likely to require the longest duration of fluoroscopy. These identified variables may help endoscopists predict which procedures are associated with prolonged fluoroscopy duration so that appropriate precautions can be undertaken.

Radiation dose to patients during endoscopic retrograde cholangiopancreatography

Endoscopic retrograde cholangiopancreatography (ERCP) is an important tool for the diagnosis and treatment of the hepatobiliary system. The use of fluoroscopy to aid ERCP places both the patient and the endoscopy staff at risk of radiation-induced injury. Radiation dose to patients during ERCP depends on many factors, and the endoscopist cannot control some variables, such as patient size, procedure type, or fluoroscopic equipment used. Previous reports have demonstrated a linear relationship between radiation dose and fluoroscopy duration. When fluoroscopy is used to assist ERCP, the shortest fluoroscopy time possible is recommended. Pulsed fluoroscopy and monitoring the length of fluoroscopy have been suggested for an overall reduction in both radiation exposure and fluoroscopy times. Fluoroscopy time is shorter when ERCP is performed by an endoscopist who has many years experience of performing ERCP and carried out a large number of ERCPs in the preceding year. In general, radiation exposure is greater during therapeutic ERCP than during diagnostic ERCP. Factors associated with prolonged fluoroscopy have been delineated recently, but these have not been validated.