Detection of Bile Leak

• Indication Overview
• Methods
• Search Results
• Summary Table
• References
• Appendix 1
• Appendix 2
• Appendix 3
• Appendix 4

Indication Overview

Perforation or blockage of the bile duct can occur after surgeries such as laparoscopic cholecystectomy or liver transplant, or could happen following trauma.¹ A retrospective and prospective study² of Canadian patients with biliary leaks post cholecystectomy reported the frequency of the symptoms that patients with leak experienced, as follows: abdominal pain (89%), fever (43%), abdominal tenderness (81%), jaundice (43%), nausea and vomiting (43%), and ascites or mass (2%).

Population: Adults and children with suspected bile leak.

Intervention: Cholescintigraphy (also known as hepatobiliary scintigraphy [HBS] or hepatobiliary iminodiacetic acid [HIDA] scan).

Nuclear imaging is used to visualize the perforations or blockages. The isotope attaches to liver cells (hepatocytes) and is excreted in bile.³ The imaging will detect bile in areas where it should not be, indicative of a leak, or will show a lack of bile in areas where it should be (such as the gall bladder), indicative of an obstruction.

The radioisotopes used for the cholescintigraphy are all iminodiacetic acid derivatives and include mebrofenin, disofenin, and diisopropyl.

Comparators: For this report, the following diagnostic tests are considered as alternatives to cholescintigraphy:

• Computed Tomography (CT): In a CT scan, a rotating x-ray device moves around the patient and takes detailed multiple images of organs and body parts.⁴ Sometimes patients are injected with a contrast dye before images are taken, for better visualization of the body part being examined.⁴ CT findings consistent with bile leak include the presence of fluid collections in the gallbladder fossa.⁵
• Endoscopic Retrograde Cholangiopancreatography (ERCP): An ERCP is a test using an endoscope and x-rays to examine a patient's bile and pancreatic ducts.⁶ During the ERCP, an endoscope is placed in the patient's mouth and passed through the esophagus, stomach, and intestine. The endoscope is a long, flexible tube that contains a lens and a light source that allows for viewing inside the body. Patients are given sedation and need to fast six to eight hours prior to the examination.⁷
• Magnetic Resonance Cholangiopancreatography (MRCP): An MRCP is a magnetic resonance imaging (MRI) test that produces detailed images of the hepatobiliary and pancreatic systems. Images are created using a magnetic field and radiofrequency pulses. Patients undergoing MRI are placed onto a table that is moved into the centre of the MRI machine. Some patients are given contrast material before the MRI. MRCP findings indicative of bile leak include the presence of fluid near the perforation site and related bile duct anomalies.⁸
• Ultrasound (U/S): During a U/S, a transducer is placed over the organ of interest. The transducer generates sound waves that pass through the body and produce echoes, which are analyzed by a computer to produce images of the body part being analyzed.⁹ In the detection of bile leak, U/S can detect fluid collections that could be indicative of bile leak in the abdomen and hepatic system.^5,10

Outcomes: Eleven outcomes (referred to as criteria) are considered in this report:

• Criterion 1: Size of the affected population
• Criterion 2: Timeliness and urgency of test results in planning patient management
• Criterion 3: Impact of not performing a diagnostic imaging test on mortality related to the underlying condition
• Criterion 4: Impact of not performing a diagnostic imaging test on morbidity or quality of life related to the underlying condition
• Criterion 5: Relative impact on health disparities
• Criterion 6: Relative acceptability of the test to patients
• Criterion 7: Relative diagnostic accuracy of the test
• Criterion 8: Relative risks associated with the test
• Criterion 9: Relative availability of personnel with expertise and experience required for the test
• Criterion 10: Accessibility of alternative tests (equipment and wait times)
• Criterion 11: Relative cost of the test.

Definitions of the criteria are in Appendix 1.

Methods

The literature search was performed by an information specialist using a peer-reviewed search strategy.

Published literature was identified by searching the following bibliographic databases: MEDLINE with In-Process records via Ovid; The Cochrane Library (2011, Issue 1) via Wiley; PubMed; and University of York Centre for Reviews and Dissemination (CRD) databases. The search strategy consisted of both controlled vocabulary, such as the National Library of Medicine's MeSH (Medical Subject Headings), and keywords. The main search concepts were radionuclide imaging and biliary leak.

Methodological filters were applied to limit retrieval to health technology assessments, systematic reviews, meta-analyses (HTA/SR/MA), randomized controlled trials, non-randomized studies, and diagnostic accuracy studies. No date or human limits were applied to the HTA/SR/MA search. For primary studies, no date limit was applied, but the search was limited to the human population. Both searches were also limited to English language documents. Regular alerts were established to update the search until October 2011. Detailed search strategies are located in Appendix 2.

Grey literature (literature that is not commercially published) was identified by searching relevant sections of the Grey Matters checklist. Google was used to search for additional web-based materials. The searches were supplemented by reviewing the bibliographies of key papers. See Appendix 2 for more information on the grey literature search strategy.

Targeted searches were done as required for the criteria, using the aforementioned databases and Internet search engines. When no literature was identified that addressed specific criteria, experts were consulted.

Search Results

Two potential clinical articles were identified through the MA/SR/HTA filtered search and neither was subjected to full text review. A total of 511 primary studies were identified with the primary studies search, of which 96 were subjected to full-text screening.

Fourteen articles were retained that provided information for the following criteria: affected population;^2,11,12 urgency;¹³ morbidity and quality of life;^13-15 acceptability of the test to patients;^16,17 diagnostic accuracy;^5,10,18-20 risks;¹⁶ and availability.¹⁶ The remaining 43 citations were articles found through searching the grey literature, articles from the targeted searches, or articles from the reference lists of the identified potential articles.

Summary table

Table 1: Summary of Criterion Evidence

Domain 1: Criteria Related to the Underlying Health Condition
Criterion		Synthesized Information
1	Size of the affected population	The number of liver transplantations in Canada has been increasing over the last decade, with 409 transplants performed in 2000 and 452 performed in 2009. Of these transplants, 65% were done in males.21 The average (SD) annual liver resection rate in Ontario in 2001 was 5.90 (4.0) per 100,000 people.22 The overall annual rate (95% confidence interval [CI]) of elective cholecystectomy in Ontario, from 1988 to 2000, was 134.6 (133.6 to 135.6) per 100,000 people for men and 367.5 (365.9 to 369.1) per 100,000 people for women.23 Incidence of bile leak ranged from 2% to 17% in patients undergoing liver transplantation, hepatectomy, or cholecystectomy. Based on the available estimates, the size of affected population may be more than 1 in 10,000 (0.01%) and less than or equal to 1 in 1,000 (0.1%).
2	Timeliness and urgency of test results in planning patient management	Imaging should take place immediately to 24 hours after onset of symptoms post-surgery. No information regarding urgency was identified. The target time frame for performing the test is in 24 hours or less and obtaining the 99mTc-based test results in the appropriate timely manner for the underlying condition has moderate impact on the management of the condition or the effective use of health care resources.
3	Impact of not performing a diagnostic imaging test on mortality related to the underlying condition	Reported in-hospital mortality rates due to bile leak vary from 7.8% to 8.8%, with 30-day mortality reported to be 2.6%. Late mortality rate (after 30 days) is reported to be 5.9%.24 Diagnostic imaging test results can have moderate impact on mortality.
4	Impact of not performing a diagnostic imaging test on morbidity or quality of life related to the underlying condition	Symptoms from bile leaks may persist for months. Sepsis, peritonitis, and liver failure are serious events associated with bile leak. These serious events have significant morbidity associated with them. Leaks may require surgical repair, which increases morbidity, mortality, and length of hospital stay in both adult and pediatric populations. Bile leak can manifest clinically after a latent period15 following blunt trauma in children. A delay in the detection of bile duct injury may result in increased morbidity, and prolonged hospitalization. Diagnostic imaging test results can have significant impact on morbidity or quality of life.

 

 

Domain 2: Criteria Comparing 99mTc with an Alternative or Comparing Between Clinical Uses
Criterion		Synthesized Information
5	Relative impact on health disparities	To be scored locally.
6	Relative acceptability of the test to patients	Cholescintigraphy Patients may have concerns about radiation exposure and the intravenous injection of a radiopharmaceutical agent. CT Patients undergoing CT scan may have concerns about radiation exposure and may also feel claustrophobic while in the scanner. This is less of a problem with new CT scanners (MIIMAC expert opinion). Patients may be required to hold their breath for a substantial period of time, which is seen as "uncomfortable" and "difficult," particularly for patients with severe abdominal pain.25 ERCP ERCP is a relatively invasive test. It involves inserting an endoscope through the patient's mouth, and down the esophagus until it reaches the duodenum. MRCP MRCP is an MRI-based imaging test. Because of the closed space of an MRI, patients may experience feelings of claustrophobia, as well as be bothered by the noise. This may be less of a problem with new MRI machines, if available (MIIMAC expert opinion). It has been reported that up to 30% of patients experience apprehension and 5% to 10% endure some severe psychological distress, panic, or claustrophobia.26,27 Some patients may have difficulty remaining still during the scan. Patients are not exposed to radiation during an MRI scan, which may be more acceptable to some.When compared, ERCP was found to be an easier test relative to expectations than MRCP, and patients reported a higher preference for MRCP than ERCP.28 U/S Some discomforts associated with U/S include cold, unspecified pain, and tenderness. In a study comparing U/S with MRI in undiagnosed shoulder pain, 100% of the patients participating said that they would be willing to undergo the U/S exam again.29 This test may be preferred in pediatric patients as there is no exposure to ionizing radiation, and the test does not require sedation. Overall, the acceptability to the patient of cholescintigraphy using 99mTc-radiolabelled isotopes is: minimally more acceptable than CT significantly more acceptable than ERCP minimally less acceptable than MRCP minimally less acceptable than U/S.
7	Relative diagnostic accuracy of the test	Diagnostic accuracy studies all had relatively small sample sizes, and the reported sensitivity, specificity, and detection rates varied considerably. See Appendix 4. While all modalities can identify fluid collection, only cholescintigraphy and MRCP can identify the fluid as bile. Therefore, MRCP may be the most suitable alternative to cholescintigraphy. Overall, the diagnostic accuracy of cholescintigraphy using 99mTc-radiolabelled isotopes is: moderately better than CT moderately lower than ERCP similar to MRCP moderately better than U/S.
8	Relative risks associated with the test	Non–radiation-related risks Cholescintigraphy Risks associated with cholescintigraphy include allergy to HIDA and pain during CCK injection (causes gallbladder contraction), chills, nausea, and rash.30 CT  Some patients may experience an allergic reaction to the contrast agent (if required).31 In addition, patients may experience mild side effects from the contrast agent, such as nausea, vomiting, or hives. ERCP  ERCP is an invasive endoscopy-based procedure and can lead to further complications.32 Prolonged cannulation may cause additional morbidity to patients and unnecessary radiation exposure.33 ERCP is also associated with a morbidity rate (15.8%). Morbidity-related complications may include pancreatitis, hemorrhage, perforation, cholangitis, perforated stent, and complications related to cardiac, respiratory, and thromboembolic systems.34 MRCP MRCP is an MRI-based exam. MRI is contraindicated in patients with metallic implants including pacemakers.35 MRI is often used in conjunction with the contrast agent Gd. Some patients may experience an allergic reaction to the contrast agent (if required).31 Gd is contraindicated in patients with renal failure or end-stage renal disease, as they are at risk of nephrogenic systemic fibrosis. Contrast-related reactions are similar to those experienced with CT. U/S  There are no reported risks associated with U/S in the literature that was reviewed. Radiation-related Risks Cholescintigraphy, CT, and ERCP are associated with radiation exposure. Effective Radiation Doses Test Effective Radiation Dose (mSv) Pediatric Effective Dose Estimate Range (mSv) Cholescintigraphy using 99mTc-disofenin or 99mTc-mebrofenin 3.136 NR CT 8.037 8.037 ERCP* 1 to 1038 0.3 to 338 MRCP (MRI) 0 0 U/S 0 0 Average background dose of radiation per year 1 to 3.037,39,40 1 to 3.037,39,40 CT = computed tomography; ERCP = endoscopic retrograde cholangiopancreatography; MRCP = magnetic resonance cholangiopancreatography; MRI = magnetic resonance imaging; mSv = millisievert; 99mTc = technetium-99m; U/S = ultrasound. Overall, the safety of cholescintigraphy using 99mTc-radiolabelled isotopes is: minimally safer than CT significantly safer than ERCP minimally less safe than MRCP minimally less safe than U/S.
9	Relative availability of personnel with expertise and experience required for the test	As of 2006 in Canada, there were 2,034 diagnostic radiologists, 221 nuclear medicine physicians, 12,255 radiological technologists, 1,781 nuclear medicine technologists, and 2,900 sonographers available across Canada. Yukon, Northwest Territories, and Nunavut do not have the available personnel to perform and interpret tests to detect bile leak. Other jurisdictions (e.g., Prince Edward Island) may offer limited nuclear medicine services. Gastroenterologists or those physicians trained in endoscopic procedures may be restricted to larger centres. Assuming the necessary equipment is available, if cholescintigraphy using 99mTc-radiolabelled isotopes is not available, it is estimated that: more than 95% of the procedures can be performed in a timely manner using CT fewer than 25% of the procedures can be performed in a timely manner using ERCP, 25-74% of the procedures can be performed in a timely manner using MRCP more than 95% of the procedures can be performed in a timely manner using U/S.
10	Accessibility of alternative tests (equipment and wait times)	Cholescintigraphy For detection of bile leak, nuclear medicine facilities with gamma cameras (including SPECT) are required. Three jurisdictions, the Yukon, the Northwest Territories, and Nunavut, do not have any nuclear medicine equipment.41 ERCP ERCP is an x-ray–based test. X-ray machines are widely available across the country. MRCP No MRI scanners are available in the Yukon, Northwest Territories, or Nunavut.42 According to the CIHI National Survey of Selected Medical Imaging Equipment database, the average number of hours of operation per week for MRI scanners in 2006-2007 ranged from 40 hours in Prince Edward Island to 99 hours in Ontario with a national average of 71 hours.41 In 2010, the average wait time for MR imaging in Canada was 9.8 weeks.43 CT No CT scanners are available in Nunavut.42 For CT scanners, the average weekly use ranged from 40 hours in Prince Edward Island to 69 hours in Ontario, with a national average of 60 hours.41 U/S The median wait time for a U/S in Canada was estimated to be 4.5 weeks in 2010.43 No information was found on the number of U/S machines available in Canada.41 Assuming the necessary expertise is available, if cholescintigraphy using 99mTc-radiolabelled isotopes is not available, it is estimated that: 95% of the procedures can be performed in a timely manner using CT 25-74% of the procedures can be performed in a timely manner using ERCP 25-74% of the procedure can be performed in a timely manner using MRCP, 95% of the procedures can be performed in a timely manner using U/S.
11	Relative cost of the test	According to our estimates, the cost of cholescintigraphy with 99mTc-based radioisotopes is $247.85. CT is minimally more costly, MRCP is moderately more costly, and ERCP is significantly more costly. Imaging using U/S is less costly than scintigraphy.   Relative costs Test Total costs ($) Cost of test relative to 99mTc-based test ($) Cholescintigraphy 247.85 Reference CT 383.85 +136.00 ERCP 1900.00 +1652.15 MRCP 652.00 +404.15 U/S 88.25 -159.60

CCK = cholecystokinin; CI = confidence interval; CIHI = Canadian Institute for Health Information; CT = computed tomography; ERCP = endoscopic retrograde cholangiopancreatography; Gd = gadolinium; HIDA = hepatobiliary iminodiacetic acid; MRCP = magnetic resonance cholangiopancreatography; MRI = magnetic resonance imaging; MRT = medical radiation technologist; NA = not available; SPECT = single-photon emission computed tomography; ^99mTc = technetium-99; U/S = ultrasound.

Criterion 1: Size of affected population (link to definition)

Bile leaks may occur after liver transplantation, hepatectomy (liver resection), trauma, or cholecystectomy. The number of liver transplantations in Canada has been increasing over the last decade, with 409 transplants performed in 2000 and 452 performed in 2009. Of these transplants, 65% were done in males.²¹ The average (SD) annual liver resection rate in Ontario in 2001 was 5.90 (4.0) per 100,000 people.²²

The overall annual rate (95% confidence interval [CI]) of elective cholecystectomy (gallbladder removal) in Ontario, from 1988 to 2000, was 134.6 (133.6 to 135.6) per 100,000 people for men and 367.5 (365.9 to 369.1) per 100,000 people for women.²³

A systematic review⁴⁴ included 55 articles reporting on biliary complications related to biliary reconstruction during liver transplantation. The authors give no details on the quality of these articles except to state that no articles published before 1990 were included. There were 11,397 cases and 936 were complicated with biliary leakage with a mean incidence of 8.2%. The mean incidence was lower for deceased-donor whole liver transplants (7.8%, 668/8,585) and higher for living-donor transplants (9.5% 268/2,812). Incidence of bile leak for liver donors is reported to be 2% to 5% from institutional data from Tucker and Heaton.⁴⁵

In a study conducted by Vigano et al., post-operative leak occurred in 5.7% of patients (34/593) who had undergone a hepatectomy.⁴⁶ Vigano et al. also reported that over the past decade, the incidence of bile leak ranged from 1.7% to 9.2%, and within a cohort of 610 consecutive hepatic resections, the incidence of bile leak was 3.6%.⁴⁶ A retrospective study of 616 patients undergoing hepatectomy from January 1989-1998 had an incidence of bile leak of 5.5%.¹² In cases of liver resection, bile leaks occur at a rate ranging from 3.6% to 17%.⁴⁷

The prognosis after a bile leak varies according to the site of the leak and the etiology.²⁴ Leaks are more common with duct-enteric anastomosis than duct-duct anastomosis.²⁴

A prospective study of 71 patients undergoing laparoscopic cholecystectomy reported an incidence of 11.3% of bile leaks.¹¹ Sixty-four patients evaluated over a five-year period in a study conducted by Barkun et al. reported an incidence rate of 1.1% in patients post laparoscopic cholecystectomy.²

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Criterion 2: Timeliness and urgency of test results in planning patient management (link to definition)

The priority for cholescintigraphy in diagnosing suspected post-operative biliary leak is stat to 24 hours after symptom onset, according to the Saskatchewan Ministry of Health (Patrick Au, Acute and Emergency Services Branch, Saskatchewan Ministry of Health: unpublished data, 2011). Delays in diagnosis and therapy frequently result in sepsis and death.²⁴

Surgical repair for an ongoing bile leak may compromise the patient, as the bile may be toxic and contribute to additional infection that could lead to poor surgical healing; therefore, some argue that early detection is best treated with drainage.¹³

A study evaluating spontaneous healing of bile leaks examined the correlation between the delay of bile leakage post-operation and interventional treatment. Of 34 patients, leaks in 26 patients healed spontaneously (76.5%), and the conservative treatment failed in eight patients (23.5%). The authors concluded that a "wait and see" approach, compared with interventional treatment (after diagnosis), is successful in most cases.⁴⁶ Delayed repair of injured biliary tracts is recommended instead of immediate repair.⁴⁵

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Criterion 3: Impact of not performing a diagnostic imaging test on mortality related to the underlying condition (link to definition)

It has been reported that 44% of patients with bile duct leaks may develop a serious post-operative complication, which could include peritonitis, sepsis, abscess, pulmonary infiltrates, and death.⁴⁸ A 30-day mortality rate of 2.6% has been reported, as well as a 7.8% in-hospital mortality rate.⁴⁸ Sepsis, leading to multisystem organ failure, is the most common cause of death.⁴⁸

Similar mortality rates were reported by Vigano et al.⁴⁶ from a study of patients with post-operative bile leakage. Two of 34 patients (5.9%) with post-operative bile leakage died. One patient died of sepsis with persistent bile leakage 46 days after onset, and the second patient experienced tumour progression with persistent bile leakage and died five months after onset.

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Criterion 4: Impact of not performing a diagnostic imaging test on morbidity or quality of life related to the underlying condition (link to definition)

In a series of case reports presented by Tucker et al., morbidity associated with bile leak included jaundice, abdominal pain, leukocytosis, fever, and shoulder pain.⁴⁵

The presence of bile and blood in the peritoneal cavity due to leakage may impair the host immune system and allow for the development of sepsis, liver failure, and mortality.¹² Bile leak from the parenchymal cut surface can lead to the development of biloma and intra-abdominal infection with abscess.⁴⁵

Vigano et al.⁴⁶ evaluated a post-operative bile leakage population of 34 patients with a mean age of 62 years. Although 76.5% patients experienced spontaneous healing after 15 days of the procedure, eight patients did not. Five patients (14.7%) developed associated morbidity accompanying leakage and three patients developed significant morbidity (8.82%), which included sepsis in two and bile peritonitis in one.⁴⁶

Persistent bile leak or drainage can lead to invasive treatment such as ERCP, sphincterotomy, and stent placement. These procedures assist in defining the location of the leak and assist with enteric biliary damage and leak closure. Nasobiliary tubes may also be used to decompress the bile duct and resolve the bile leak.^45,47 Although leaks do heal over time with such interventions, they may persist for months.⁴⁷ In some cases, surgical repair or biliary reconstruction, including revising the Roux-en-Y hepaticojejunostomy, creating a new hepaticojejunostomy, or reinforcing the anastomosis with polydioxanone suture (PDS).¹³

One study¹⁴ that followed 40 patients hospitalized after trauma reported statistically significantly (P < 0.0001) longer hospital stays for patients who experienced bile leaks compared with those who did not have bile leaks. The mean (SD) length of hospital stay was 53 days (24 days; range 26 to 70 days) for bile leaks compared with a mean of 14 days (12 days; range three days to 61 days) for patients with no bile leaks.

Pediatric
Bile leak can manifest clinically after a latent period¹⁵ following blunt trauma in children. A delay in the diagnosis of bile duct injury may result in increased morbidity and prolonged hospitalization.

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Criterion 5: Relative impact on health disparities (link to definition)

To be scored locally.

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Criterion 6: Relative acceptability of the test to patients (link to definition)

Cholescintigraphy
Patients may have concerns about radiation exposure and the intravenous injection of a radiopharmaceutical agent.

CT
Patients undergoing CT scan may have concerns about radiation exposure and may also feel claustrophobic while in the scanner. This is less of a problem with new CT scanners (MIIMAC expert opinion). Patients may be required to hold their breath for a substantial period of time, which is seen as "uncomfortable" and "difficult," particularly for patients with severe abdominal pain.²⁵

ERCP
ERCP is a relatively invasive test. It involves inserting an endoscope through the patient's mouth, and down the esophagus until it reaches the duodenum. Patients with altered surgical anatomy may not be suitable for ERCP, especially in cases where a Roux-en-Y anastomosis is required due to unusual anatomical features post-surgery.¹⁶

MRCP
MRCP is an MRI-based imaging test. Because of the closed space of an MRI, patients may experience feelings of claustrophobia, as well as be bothered by the noise. This may be less of a problem with new MRI machines, if available (MIIMAC expert opinion). It has been reported that up to 30% of patients experience apprehension and 5% to 10% endure some severe psychological distress, panic, or claustrophobia.^26,27 Some patients may have difficulty remaining still during the scan. Patients are not exposed to radiation during an MRI scan, which may be more acceptable to some.

Menon et al.²⁸ compared patient satisfaction in 34 patients who underwent both ERCP and MRCP. Patients completed a questionnaire using a Likert scale that measured anxiety, pain, and discomfort related to each test. Additionally, the patients rated their willingness to repeat each test and how difficult each test was, compared with their expectations. ERCP was rated as having statistically significant worse pain (ERCP 2.78, MRCP 2.44), and more discomfort (ERCP 3.09, MRCP 2.47) compared with MRCP. Although not statistically significant, patients were less willing to repeat ERCP than MRCP (ERCP = –1.30, MRCP = –0.72). ERCP was found to be an easier test relative to expectations than MRCP. When patients were asked to directly compare ERCP with MRCP, ERCP was rated as more anxiety provoking, more painful, and more uncomfortable. These were all statistically significant except for the comfort domain. Patients also reported a higher preference for MRCP than ERCP.

U/S
Some discomforts associated with U/S include cold, unspecified pain, and tenderness. In a study comparing U/S with MRI in undiagnosed shoulder pain, 100% of the patients participating said that they would be willing to undergo the U/S exam again.²⁹ This test may be preferred in pediatric patients as there is no exposure to ionizing radiation, and the test does not require sedation.

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Criterion 7: Relative diagnostic accuracy of the test (link to definition)

A study by Banzo et al.¹⁰ evaluated the utility of hepatobiliary scintigraphy (cholescintigraphy) using ^99mTc-mebrofenin for the diagnosis of bile leak in patients post liver transplant, who complained of abdominal pain after removal of the T-tube. A total of 20 patients with a mean age of 44 years old were enrolled, of which 13 were diagnosed with bile leak using cholescintigraphy, U/S, or ERCP. All 13 cases underwent cholescintigraphy; 10 cases were administered both cholescintigraphy and U/S; and six cases evaluated cholescintigraphy and ERCP. The results are presented for U/S compared with cholescintigraphy and ERCP compared with cholescintigraphy in Table 3.

Table 3: Bile Leaks Found by Cholescintigraphy Compared with Collections Identified by U/S and ERCP¹⁰

U/S	Cholescintigraphy
	Positive	Negative		Total
Positive	8	1		9
Negative	1	0		1
Total	9	1		10
ERCP	Cholescintigraphy
	Positive		Negative	Total
Positive	6		0	6
Negative	0		0	0
Total	6		0	6

ERCP = endoscopic retrograde cholangiopancreatography; U/S = ultrasound.

Based on the values in Table 3, the sensitivity and specificity of U/S was 88.89% and 0%, respectively. The sensitivity for ERCP was 100% compared with cholescintigraphy. With regard to the diagnostic accuracy of cholescintigraphy, it is sensitive for detecting bile leaks, but a negative result should be an indication for an ERCP. In addition, cholescintigraphy highlights the relationship between ultrasonographic collections and the biliary system.¹⁰

Trerotola et al.⁵ evaluated the spectrum of biliary complications associated with laparoscopic cholecystectomy, and assessed various imaging modalities. Cases from December 1989 through July 1991 were reviewed and cholescintigraphy using ^99mTc-disofenin, as well as U/S, CT, ERCP and percutaneous transhepatic cholangiography (an x-ray–based imaging modality), were included as comparators. During the review period, 13 patients were identified who met the inclusion criteria. Bile leaks were considered minor complications and detection rates were reported. The detection rates for bile leak and stricture with ERCP were reported as a combined value of 88% (7/8). All other comparators reported detection rates for bile leak independently. Cholescintigraphy detected biliary complications in 100% of cases (6/6). CT (0/4) and US (0/3) were not able to detect bile leak, as the fluid collections shown during imaging were non-specific.⁵

Walker et al.²⁰ evaluated the disruption of the bile duct and biloma after laparoscopic cholecystectomy in 1991. A total of 263 case reports of laparoscopic cholecystectomies were reviewed and seven cases of bile leak and biloma were assessed to compare the imaging evaluation of CT, U/S, ERCP, and cholescintigraphy using the radiotracer ^99mTc-diisopropyliminodiacetic acid (^99mTc-DISIDA). Of the seven cases, five underwent cholescintigraphy and the sensitivities for each test were calculated using cholescintigraphy as the reference standard from the information provided.²⁰ U/S and CT scans identified fluid accumulations in the peritoneal cavity, while cholescintigraphy identified accumulations of radiolabelled bile.

Table 4: Bile Leaks Found by Cholescintigraphy Compared with Collections Identified by U/S²⁰

U/S	Cholescintigraphy
	Positive	Negative	Total
Positive	2 (1)	0	2
Negative	1 (2)	0	1
Total	3	0	3
CT	Cholescintigraphy
	Positive	Negative	Total
Positive	4 (2)	0	4
Negative	0 (2)	0	0
Total	4	0	4
Positive	2 (2)	0	2
Negative	1 (1)	0	1
Total	3	0	3

CT = computed tomography; ERCP = endoscopic retrograde cholangiopancreatography; U/S = ultrasound.

In comparison to the cholescintigraphy using the radiotracer ^99mTc-DISIDA, the sensitivities of U/S, CT, and ERCP were 67%, 100%, and 67%, respectively, when peritoneal fluid was used as an indicator of bile leak. If peritoneal fluid was not considered an indicator of bile leak, the respective sensitivities were 33%, 50%, and 67%. Specificity could not be calculated, as the prevalence of bile leak in the population observed was 100%.²⁰

The authors concluded that CT and U/S were helpful in detecting abdominal fluid collections but could not differentiate bile from other fluids, while cholescintigraphy was quite useful. Cholescintigraphy would be a preferred method to ERCP as it is a non-invasive comparator; however, ERCP and percutaneous transhepatic cholangiography (PTC) may still be used to localize the exact point of leakage.²⁰

Rayter et al.⁴⁹ enrolled 35 patients undergoing elective cholecystectomy for gallstones and determined the frequency of bile leaks. After the surgery, each patient underwent cholescintigraphy and then immediately afterwards had a U/S scan. The results are presented in Table 5.

Table 5: Bile Leaks Found by HIDA Scanning Compared with Collections Identified by U/S⁴⁹

U/S scan	HIDA scan
	Positive	Negative	Total
Positive	5	15	20
Negative	6	9	15
Total	11	24	35

HIDA = hepatobiliary iminodiacetic acid scan; U/S = ultrasound.

Based on the values in Table 5, the specificity and sensitivity of the U/S scans are 37.5% and 45.5%, respectively.

MRCP
No information was found comparing the diagnostic accuracy of MRCP with cholescintigraphy in the detection of bile leak.

Pediatric population
In 2010, Lee et al.⁸ conducted a retrospective review to evaluate the diagnostic usefulness of MRCP in the pediatric population where spontaneous bile duct perforation occurred. Cases from more than 10 years (March 1999 to February 2009) from a hospital database in Korea were reviewed, and three children were identified with the indication and relative comparator. MRCP was compared with U/S and cholescintigraphy using ^99mTc-mebrofenin. In two of the three cases, MRCP, cholescintigraphy, and U/S were used in the detection of bile leak.

Table 6: Bile Leaks Found by Cholescintigraphy Scanning Compared with Collections Identified by U/S⁸

U/S	Cholescintigraphy
	Positive	Negative	Total
Positive	1	0	1
Negative	1	0	1
Total	2	0	2
MCRP	Cholescintigraphy
	Positive	Negative	Total
Positive	2	0	2
Negative	0	0	0
Total	2	0	2

MRCP = magnetic resonance cholangiopancreatography; U/S = ultrasound.

Based on the values in Table 6, the sensitivity of the U/S scan was 50% and the sensitivity for MRCP was 100% compared with cholescintigraphy. The authors concluded that U/S is the method of choice in children, but the field of view is limited. Cholescintigraphy provides useful information but exposes children to radiation and lacks anatomical information. MRCP was useful and able to detect fluid accumulation in all cases adjacent to the perforation site.

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Criterion 8: Relative risks associated with the test (link to definition)

Non–radiation-related Risks

Cholescintigraphy 
Risks associated with cholescintigraphy include allergy to HIDA, pain during cholecystokinin (CCK) injection (causes gallbladder contraction), chills, nausea, and rash.³⁰ Rapid administration of CCK has been associated with deterioration in blood gases and respiratory function in infants.⁵⁰ In a study of 18 subjects, slow infusion of CCK resulted in no adverse reactions, specifically abdominal pain, which was present in the group that had a bolus injection.⁵⁰ Slow infusion of CCK is now a well-recognized practice (MIIMAC expert opinion). In susceptible subjects, CCK has induced panic attacks.⁵⁰

CT
Some patients may experience an allergic reaction to the contrast agent (if required), which may worsen with repeated exposure.³¹ In addition, patients may experience mild side effects from the contrast agent, such as nausea, vomiting, or hives. A 2009 retrospective review of all intravascular doses of low-osmolar iodinated and Gd contrast materials administered at the Mayo Clinic between 2002 and 2006 (456,930 doses) found that 0.15% of patients given CT contrast material experienced side effects, most of which were mild. A serious side effect was experienced by 0.005% of patients.⁵¹ CT is contraindicated in patients with elevated heart rate, hypercalcemia, and impaired renal function. Specifically, Gd is contraindicated in patients with renal failure or end-stage renal disease, as they are at risk of nephrogenic systemic fibrosis. According to the American College of Radiology Manual on Contrast Media,⁵² the frequency of severe, life-threatening reactions with Gd is extremely rare (0.001% to 0.01%). Moderate reactions resembling an allergic response (i.e., rash, hives, urticaria) are also very unusual and range in frequency from 0.004% to 0.7%.⁵²

ERCP 
ERCP is an invasive endoscopy-based procedure and can lead to further complications.³² Prolonged cannulation may cause additional morbidity to patients and unnecessary radiation exposure.³³ ERCP is also associated with a high morbidity rate. In an uncontrolled prospective study conducted by Christensen, the procedure-related mortality rate was 1.0% in a population of 1,177 procedures, and overall 30-day mortality was 5.8%. Morbidity-related complications occurring in 15.8% of the population included pancreatitis, hemorrhage, perforation, cholangitis, perforated stent, and complications related to cardiac, respiratory, and thromboembolic systems.³⁴

MRI
MRI is contraindicated in patients with metallic implants, including pacemakers.³⁵ MRI is often used in conjunction with the contrast agent Gd. Some patients may experience an allergic reaction to the contrast agent (if required), which may worsen with repeated exposure.³¹ Side effects of Gd include headaches, nausea, and metallic taste. Gd is contraindicated in patients with renal failure or end-stage renal disease, as they are at risk of nephrogenic systemic fibrosis. According to the American College of Radiology Manual on Contrast Media,⁵² the frequency of severe, life-threatening reactions with Gd is extremely rare (0.001% to 0.01%). Moderate reactions resembling an allergic response (i.e., rash, hives, urticaria) are also very unusual and range in frequency from 0.004% to 0.7%.⁵²

U/S 
There are no reported risks associated with U/S in the literature that was reviewed.

Radiation-related Risks

Among the modalities to diagnose bile leak, cholescintigraphy, CT, and ERCP expose the patient to ionizing radiation. The average effective dose of radiation delivered with each of these procedures can be found in Table 7.

Table 7: Effective Radiation Doses for Various Imaging Tests

Test	Effective Radiation Dose (mSv)	Pediatric Effective Dose Estimate Range (mSv)
99mTc-disofenin	3.136	NR
99mTc-mebrofenin	3.136	NR
CT	8.037	8.037
ERCP*	1 to 1038	0.3 to 338
MRCP (MRI)	0	0
U/S	0	0
Average background dose of radiation per year	1-3.037,39,40	1-3.037,39,40

CT = computed tomography; ERCP = endoscopic retrograde cholangiopancreatography; GI = gastrointestinal; MRCP = magnetic resonance cholangiopancreatography; NR = not reported; ^99mTc-disofenin = technetium-99m disofenin; ^99mTc-mebrofenin = technetium-99m mebrofenin; U/S = ultrasound.

*Based on x-ray of abdomen and upper GI series with bowel follow-through.³⁸

Return to Summary Table

Criterion 9: Relative availability of personnel with expertise and experience required for the test (link to definition)

Cholescintigraphy 
In Canada, physicians involved in the performance, supervision, and interpretation of hepatobiliary scans should be nuclear medicine physicians or diagnostic radiologists with training or expertise in nuclear imaging.⁵³ Physicians should have a Fellowship of Certification in Nuclear Medicine or Diagnostic Radiology with the Royal College of Physicians and Surgeons of Canada and/or the Collège des médecins du Québec. Nuclear medicine technologists are required to conduct cholescintigraphy. Technologists must be certified by the Canadian Association of Medical Radiation Technologists (CAMRT) or an equivalent licensing body.

All alternative imaging modalities
In Canada, physicians involved in the performance, supervision, and interpretation of diagnostic CT scans, MRI, and U/S should be diagnostic radiologists⁴¹ and must have a Fellowship or Certification in Diagnostic Radiology with the Royal College of Physicians and Surgeons of Canada and/or the Collège des médecins du Québec. Foreign-trained radiologists also are qualified if they are certified by a recognized certifying body and hold a valid provincial license.⁵³

Service engineers are needed for system installation, calibration, and preventive maintenance of the imaging equipment at regularly scheduled intervals. The service engineer's qualification will be ensured by the corporation responsible for service and the manufacturer of the equipment used at the site.

Qualified medical physicists (on-site or contracted part-time) should be available for the installation, testing, and ongoing quality control of CT scanners, MR scanners, and nuclear medicine equipment.⁵³

CT
For the performance of CT scan, medical radiation technologists who are certified by CAMRT, or an equivalent licensing body recognized by CAMRT, are required. The training of technologists specifically engaged in CT should meet with the applicable and valid national and provincial specialty qualifications.

ERCP
ERCP is an x-ray–based test performed by gastroenterologists. Gastroenterologists must have certification from the Royal College of Physicians and Surgeons of Canada (or Collège des médecins du Québec). ERCP is performed mostly by gastroenterologists with advanced endoscopy training, lasting one or two years after completion of the mandatory two-year subspecialty program.⁵⁴

Expert endoscopists have a higher rate of successful cannulation, while novices have lower success rates and increased complication rates.¹⁶

Jowell et al.⁵⁵ completed a study evaluating the competency of gastroenterology fellows (at various stages of training) to complete an ERCP. Fellows performed this procedure under the watchful eye of an experienced therapeutic endoscopist. The fellows were graded on various technical aspects of the procedure, using a five-point scale: 1-excellent; 2-adequate; 3-partially successful; 4-failed; 5-no attempt. If the fellow achieved a score of 1 or 2, this was considered acceptable. Adequate skill in a particular component of the exam was arbitrarily defined as reflecting competency if the probability of an acceptable score was 0.8. The results of this study state that 160 ERCPs have to be done before a fellow achieves adequate skills. A more recent report states that the Canadian Association of Gastroenterology recommends at least 180 procedures should be performed before competence can be assessed.⁵⁶ According to the Endoscopy Committee of the Canadian Association of Gastroenterology, ERCP is one of the most technically demanding and highest-risk procedures performed by endoscopists.⁵⁴

MRCP
Medical technologists must have CAMRT certification in magnetic resonance or be certified by an equivalent licensing body recognized by CAMRT.

U/S
Sonographers (or ultrasonographers) should be graduates of an accredited school of sonography or have obtained certification from the Canadian Association of Registered Diagnostic Ultrasound Professionals. They should be members of their national or provincial professional organization. Sonography specialties include general sonography, vascular sonography, and cardiac sonography.⁴¹ In Quebec, sonographers and medical radiation technologists are grouped together; in the rest of Canada, sonographers are considered a distinct professional group.⁴¹

The availability of expertise to image bile leak varies across the jurisdictions. Table 8 reports the number of medical imaging professionals nationally and highlights those provinces and territories that lack a specific expertise. Gastroenterologists are not included in this list; however, the number of gastroenterologists in Canada available to perform the procedure is reported to be 1.83 per 100,000 persons.⁵⁷

Table 8: Medical Imaging Professionals in Canada⁴¹

Jurisdiction	Diagnostic Radiology Physician	Nuclear Medicine Physician	Medical Radiation Technologists	Nuclear Medicine Technologists	Sonographers	Medical Physicist
NL	46	3	263	15	NR	NR
NS	71	5	403	71	NR	NR
NB	47	3	387	55	NR	NR
PE	7	0	57	3	NR	0
QC	522	90	3,342	460	NR	NR
ON	754	69	4,336	693	NR	NR
MB	58	8	501	42	NR	NR
SK	61	4	359	36	NR	NR
AB	227	18	1,229	193	NR	NR
BC	241	21	1,352	212	NR	NR
YT	0	0	0	0	NR	0
NT	0	0	26	1	NR	0
NU	0	0	0	0	NR	0
Total	2,034	221	12,255	1,781	2,900*	322*

AB = Alberta; BC = British Columbia; MB = Manitoba; NB = New Brunswick; NL = Newfoundland and Labrador; NR = not reported by jurisdictions; NS = Nova Scotia; NT = Northwest Territories; NU = Nunavut; ON = Ontario; PE = Prince Edward Island; QC = Quebec; YT = Yukon.

*This represents a total for all of the jurisdictions.

Return to Summary Table

Criterion 10: Accessibility of alternative tests (equipment and wait times) (link to definition)

There are notable variations in the availability of medical imaging technologies across Canada. Table 9 provides an overview of the availability of equipment required to diagnose bile leak. Data for nuclear medicine cameras (including SPECT) are current to January 1, 2007. The number of CT, MRI, and SPECT/CT scanners is current to January 1, 2010. Data were not available for U/S.

Table 9: Diagnostic Imaging Equipment in Canada^41,42

	Nuclear Medicine Cameras	CT Scanners	MRI Scanners	SPECT/CT Scanners
Number of devices	60341	46042	21842	9642
Average number of hours of operation per week (2006-2007)41	40	60	71	n/a
Provinces and Territories with no devices available	YT, NT, NU	NU	YT, NT, NU	PE, YT, NT, NU

NT = Northwest Territories; NU = Nunavut; PE = Prince Edward Island; YT = Yukon

Cholescintigraphy 
To perform cholescintigraphy, nuclear medicine facilities with gamma cameras (including SPECT) are required. Three jurisdictions, the Yukon, the Northwest Territories, and Nunavut, do not have any nuclear medicine equipment.⁴¹

CT
No CT scanners are available in Nunavut.⁴² The average weekly use of CT scanners ranged from 40 hours in PEI to 69 hours in Ontario, with a national average of 60 hours.⁴¹ In 2010, the average wait time for a CT scan in Canada is 4.2 weeks.⁴³

ERCP
ERCP is an x-ray–based test. X-ray machines are widely available across the country.

MRCP 
MRCP is an MRI based test. No MRI scanners available in the Yukon, Northwest Territories, or Nunavut.⁴² According to CIHI's National Survey of Selected Medical Imaging Equipment database, the average number of hours of operation per week for MRI scanners in 2006–2007 ranged from 40 hours in PEI to 99 hours in Ontario with a national average of 71 hours.⁴¹ In 2010, the average wait time for MR imaging in Canada was 9.8 weeks.⁴³

U/S
U/S machines are widely available across the country. According to the Fraser Institute, the average wait time for U/S in 2010 was 4.5 weeks.⁴³

Return to Summary Table

Criterion 11: Relative cost of the test (link to definition)

Fee codes from the Ontario Schedule of Benefits were used to estimate the relative costs of cholescintigraphy and its alternatives. Technical fees are intended to cover costs incurred by the hospital (i.e., radiopharmaceutical costs, medical/surgical supplies, and non-physician salaries). Maintenance fees are not billed to OHIP — estimates here were provided by St. Michael's Hospital in Toronto. Certain procedures (i.e., PET scan, CT scan, MRI scan) are paid for, in part, out of the hospital's global budget; these estimates were provided by The Ottawa Hospital. It is understood that the relative costs of imaging will vary from one institution to the next.

According to our estimates (Table 9), the cost of cholescintigraphy with ^99mTc-based radioisotopes is $247.85. CT is minimally more costly, MRCP is moderately more costly, and U/S is minimally less costly than cholescintigraphy. An estimate for ERCP could not be obtained; however, actual costs (i.e., excluding professional fees) obtained from one Ontario hospital were reported to be approximately $1900. Therefore, ERCP is a significantly more costly alternative.

Table 9: Cost Estimates Based on the Ontario Schedule of Benefits for Physician Services Under the Health Insurance Act (September 2011)⁵⁸

Fee Code	Description	Tech. Fees ($)	Prof. Fees ($)	Total Costs ($)
Cholescintigraphy
J804	First transit — without blood pool images	16.50	20.95	37.45
J831	Biliary scintigraphy	117.45	50.95	168.4
Maintenance fees — from global budget		42.00		42.00
TOTAL		175.95	71.90	247.85
CT
X410	Abdominal CT — with IV contrast		102.65	102.65
X232	Pelvic CT — with IV contrast		102.65	102.65
Technical cost — from global budget		150.00		150.00
Maintenance fees — from global budget		28.55		28.55
TOTAL		178.55	205.30	383.85
MRCP
X451C	MRI — abdomen — multislice sequence		77.20	77.20
X455C (×3)	Repeat (another plane, different pulse sequence — to a maximum of 3 repeats)		115.95	115.95
X499C	3-D MRI acquisition sequence, including post-processing (minimum of 60 slices; maximum 1 per patient per day)		65.50	65.40
X487C	Gadolinium		38.60	38.60
Technical cost — from global budget		300.00		300.00
Maintenance fees — from global budget		54.75		54.75
TOTAL		354.75	297.25	652.00
U/S
J135	Complete abdominal scan	50.00	34.95	84.95
Maintenance fees — from global budget		3.30		3.30
TOTAL		53.30	34.95	88.25

3-D = three-dimensional; anes = anesthetic; CT = computed tomography; ERCP = endoscopic retrograde cholangiopancreatography; MRCP = magnetic resonance cholangiopancreatography; MRI = magnetic resonance imaging; prof = professional; spec = specialist; tech. = technical; U/S = ultrasound.

Return to Summary Table

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61. The Free Dictionary [Internet]. Huntingdon Valley (PA): Farlex; 2011. Biloma; 2011 [cited 2011 Aug 3]. Available from: http://medical-dictionary.thefreedictionary.com/biloma
62. The Free Dictionary [Internet]. Huntingdon Valley (PA): Farlex; 2011. Hepaticojejunostomy; 2011 [cited 2011 Aug 3]. Available from: http://medical-dictionary.thefreedictionary.com/Hepaticojejunostomy

 

Appendix 1: Multi-Criteria Decision Analysis Definitions

Domain 1: Criteria Related to the Underlying Health Condition
Criterion	Definition
1. Size of the affected population	The estimated size of the patient population that is affected by the underlying health condition and that may potentially undergo the test. The ideal measure is point prevalence, or information on how rare or common the health condition is.
2. Timeliness and urgency of test results in planning patient management	The timeliness and urgency of obtaining the test results in terms of their impact on the management of the condition and the effective use of health care resources.
3. Impact of not performing a diagnostic imaging test on mortality related to the underlying condition	Impact of not performing the test, in whatever way, on the expected mortality of the underlying condition. Measures could include survival curves showing survival over time, and/or survival at specific time intervals with and without the test.
4. Impact of not performing a diagnostic imaging test on morbidity or quality of life related to the underlying condition	Impact of not performing the test, in whatever way, on the expected morbidity or on the quality of life reduction of the underlying condition. Measures of impact may include natural morbidity outcome measures such as events or disease severity, or might be expressed using generic or disease-specific quality of life rating scales with and without the test.
Domain 2: Criteria Comparing 99mTc with an Alternative, or Comparing between Clinical Uses
Criterion	Definition
5. Relative impact on health disparities	Health disparities are defined as situations where there is a disproportionate burden (e.g., incidence, prevalence, morbidity, or mortality) amongst particular population groups (e.g., gender, age, ethnicity, geography, disability, sexual orientation, socioeconomic status, and special health care needs). Impact on health disparities is assessed by estimating the proportion of current clients of the technetium-99m (99mTc)-based test that are in population groups with disproportionate burdens. (Explanatory note: The implication of this definition is that, everything else being the same, it is preferable to prioritize those clinical uses that have the greatest proportion of clients in groups with disproportionate burdens.)
6. Relative acceptability of the test to patients	Acceptability of the 99mTc-based test from the patient's perspective compared with alternatives. Patient acceptability considerations include discomfort associated with the administration of the test, out-of-pocket expenses or travel costs, factors that may cause great inconvenience to patients, as well as other burdens. This criterion does not include risks of adverse events but is about everything related to the experience of undergoing the test.
7. Relative diagnostic accuracy of the test	Ability of the test to correctly diagnose the patients who have the condition (sensitivity) and patients who do not have the condition (specificity) compared with alternatives.
8. Relative risks associated with the test	Risks associated with the test (e.g., radiation exposure, side effects, adverse events) compared with alternatives. Risks could include immediate safety concerns from a specific test or long-term cumulative safety concerns from repeat testing or exposure.
9. Relative availability of personnel with expertise and experience required for the test	Availability of personnel with the appropriate expertise and experience required to proficiently conduct the test and/or interpret the test findings compared with alternatives.
10. Accessibility of alternatives (equipment and wait times)	Availability (supply) of equipment and wait times for alternative tests within the geographic area. Includes consideration of the capacity of the system to accommodate increased demand for the alternatives. Excludes any limitation on accessibility related to human resources considerations.
11. Relative cost of the test	Operating cost of test (e.g., consumables, heath care professional reimbursement) compared with alternatives.

 

Appendix 2: Literature Search Strategy

OVERVIEW
Interface:		Ovid
Databases:		Ovid MEDLINE In-Process & Other Non-Indexed Citations and Ovid MEDLINE <1948 to March 14, 2011>
Date of Search:		March 15, 2011
Alerts:		Monthly search updates began March 14, 2011 and ran until October 2011.
Study Types:		Health technology assessments, systematic reviews, meta-analyses, randomized controlled trials, non-randomized studies, and diagnostic accuracy studies.
Limits:		No date limit English language Human limit for primary studies
SYNTAX GUIDE
/	At the end of a phrase, searches the phrase as a subject heading
MeSH	Medical subject heading
.fs	Floating subheading
exp	Explode a subject heading
*	Before a word, indicates that the marked subject heading is a primary topic; or, after a word, a truncation symbol (wildcard) to retrieve plurals or varying endings
?	Truncation symbol for one or no characters only
ADJ	Requires words are adjacent to each other (in any order)
ADJ#	Adjacency within # number of words (in any order)
.ti	Title
.ab	Abstract
.hw	Heading word: usually includes subject headings and controlled vocabulary
.tw	Text word: searches title, abstract, captions, and full text
.mp	Keyword search: includes title, abstract, name of substance word, subject heading word and other text fields
.pt	Publication type
.nm	Name of substance word: used to search portions of chemical names and includes words from the CAS Registry/EC Number/Name (RN) fields
.jw	Journal words: searches words from journal names
/du	Diagnostic use
/ri	Radionuclide imaging

 

Ovid MEDLINE Strategy
Line #	Search Strategy
1	Technetium/
2	exp Technetium Compounds/
3	exp Organotechnetium Compounds/
4	exp Radiopharmaceuticals/
5	radioisotope*.mp.
6	(technetium* or Tc-99* or Tc99* or Tc-99m* or Tc99m* or 99mTc* or 99m-Tc* or 99mtechnetium* or 99m-technetium*).tw,nm.
7	Radionuclide Imaging/ or Perfusion Imaging/
8	ri.fs.
9	((radionucl* or nuclear or radiotracer* or hepatobiliary or biliary or lidofenin or gadolinium-HIDA or Gd-HIDA or hepato-iminodiacetic acid or HIDA or 99mTc-IDA) adj2 (imag* or scan* or test* or diagnos*)).tw.
10	(SPECT or scintigraph* or scintigram* or scintiphotograph* or cholescintigraph*).tw.
11	Tomography, Emission-Computed, Single-Photon/
12	(single-photon adj2 emission*).tw.
13	(lidofenin or gadolinium-HIDA or Gd-HIDA or hepato-iminodiacetic acid or HIDA or 99mTc-IDA).tw,nm.
14	(59160-29-1 or 73121-98-9).rn.
15	or/1-14
16	Bile Duct Diseases/
17	exp Bile Ducts/in
18	Bile/
19	((bile or biliary) adj5 leak*).mp.
20	((bile duct* or biliary duct*) adj5 (complicat* or injur*)).tw.
21	or/16-20
22	Meta-Analysis.pt.
23	Meta-Analysis/ or Systematic Review/ or Meta-Analysis as Topic/ or exp Technology Assessment, Biomedical/
24	((systematic* adj3 (review* or overview*)) or (methodologic* adj3 (review* or overview*))).tw.
25	((quantitative adj3 (review* or overview* or synthes*)) or (research adj3 (integrati* or overview*))).tw.
26	((integrative adj3 (review* or overview*)) or (collaborative adj3 (review* or overview*)) or (pool* adj3 analy*)).tw.
27	(data synthes* or data extraction* or data abstraction*).tw.
28	(handsearch* or hand search*).tw.
29	(mantel haenszel or peto or der simonian or dersimonian or fixed effect* or latin square*).tw.
30	(met analy* or metanaly* or health technology assessment* or HTA or HTAs).tw.
31	(meta regression* or metaregression* or mega regression*).tw.
32	(meta-analy* or metaanaly* or systematic review* or biomedical technology assessment* or bio-medical technology assessment*).mp,hw.
33	(medline or Cochrane or pubmed or medlars).tw,hw.
34	(cochrane or health technology assessment or evidence report).jw.
35	or/22-34
36	exp "Sensitivity and Specificity"/
37	False Positive Reactions/
38	False Negative Reactions/
39	du.fs.
40	sensitivit*.tw.
41	(predictive adj4 value*).tw.
42	distinguish*.tw.
43	differentiat*.tw.
44	enhancement.tw.
45	identif*.tw.
46	detect*.tw.
47	diagnos*.tw.
48	accura*.tw.
49	comparison*.tw.
50	Comparative Study.pt.
51	(Validation Studies or Evaluation Studies).pt.
52	Randomized Controlled Trial.pt.
53	Controlled Clinical Trial.pt.
54	(Clinical Trial or Clinical Trial, Phase II or Clinical Trial, Phase III or Clinical Trial, Phase IV).pt.
55	Multicenter Study.pt.
56	(random* or sham or placebo*).ti.
57	((singl* or doubl*) adj (blind* or dumm* or mask*)).ti.
58	((tripl* or trebl*) adj (blind* or dumm* or mask*)).ti.
59	(control* adj3 (study or studies or trial*)).ti.
60	(non-random* or nonrandom* or quasi-random* or quasirandom*).ti.
61	(allocated adj "to").ti.
62	Cohort Studies/
63	Longitudinal Studies/
64	Prospective Studies/
65	Follow-Up Studies/
66	Retrospective Studies/
67	Case-Control Studies/
68	Cross-Sectional Study/
69	(observational adj3 (study or studies or design or analysis or analyses)).ti.
70	cohort.ti.
71	(prospective adj7 (study or studies or design or analysis or analyses or cohort)).ti.
72	((follow up or followup) adj7 (study or studies or design or analysis or analyses)).ti.
73	((longitudinal or longterm or (long adj term)) adj7 (study or studies or design or analysis or analyses or data or cohort)).ti.
74	(retrospective adj7 (study or studies or design or analysis or analyses or cohort or data or review)).ti.
75	((case adj control) or (case adj comparison) or (case adj controlled)).ti.
76	(case-referent adj3 (study or studies or design or analysis or analyses)).ti.
77	(population adj3 (study or studies or analysis or analyses)).ti.
78	(cross adj sectional adj7 (study or studies or design or research or analysis or analyses or survey or findings)).ti.
79	or/36-78
80	Case Reports.pt.
81	79 not 80
82	15 and 21 and 35
83	limit 82 to english language
84	15 and 21 and 81
85	limit 84 to (english language and humans)

 

OTHER DATABASES
PubMed	Same MeSH, keywords, limits, and study types used as per MEDLINE search, with appropriate syntax used.
Cochrane Library Issue 1, 2011	Same MeSH, keywords, and date limits used as per MEDLINE search, excluding study types and Human restrictions. Syntax adjusted for Cochrane Library databases.

 

GREY LITERATURE SEARCHING
Dates for Search:	March 2011
Keywords:	Included terms for radionuclide imaging and gastrointestinal hemorrhage.
Limits:	No limits

The following sections of the grey literature checklist, "Grey matters: a practical tool for evidence-based medicine" were searched:

• Health Technology Assessment Agencies (selected)
• Clinical Practice Guidelines
• Databases (free)
• Internet Search.

 

Appendix 3: Definitions

Ascites: The accumulation of serous fluid in the peritoneal cavity.^59,60

Anastomosis: The surgical or pathological connection of two tubular structures.^59,60

Biloma: An encapsulated collection of bile in the peritoneal cavity.⁶¹

Peritoneal cavity: A potential space between the layers of the parietal and visceral peritoneum (membrane reflected over the viscera and the lining of the abdominal cavity). A small amount of fluid is contained in the space. Thus, friction is minimized as the viscera glide on each other, or against the wall of the abdominal cavity.^59,60

Polydioxanone suture: Polydioxanone (PDS, Ethicon) is a monofilament absorbable suture that retains its integrity in tissues twice as long as any other synthetic absorbable suture. It is claimed to be slowly absorbed following hydrolysis, causing a minimal tissue reaction, and therefore should be less likely to promote infection.⁵⁹

Roux-en-Y hepaticojejunostomy: Anastomosis of the distal divided end of the small bowel to another organ such as the stomach or oesophagus. The proximal end is anastomosed anastomosis of the hepatic duct to the jejunum.^59,60,62

Sphincterotomy: Excision of any sphincter muscle.^59,60

 

Appendix 4: Diagnostic Accuracy

Table 13: Diagnostic Accuracy of Hepatobiliary Scan and the Alternative Tests Based on the Information Presented in the Included Studies

Study	Population size/ (Mean Age)	Diagnostic accuracy of tests (%)
		Chole	ERCP	U/S	CT	MRCP
Walker et al. 1992*	Seven patients post-cholecystectomy (mean age: 54 years)	Reference	If collection of perihepatic fluid only used as detection Sens: 67.7% If collection of peritoneal fluid used as detection Sens: 67.7%	If collection of perihepatic fluid only used as detection Sens: 33% If collection of peritoneal fluid used as detection Sens: 100%	If collection of perihepatic fluid only used as detection Sens: 50% If collection of peritoneal fluid used as detection Sens: 67.7%	NA
Banzo et al. 1998	13 patients post T-tube removal of liver transplantation (mean age: 44 years)	NA	Sens:100% Spec: NA	Sens: 88.89% Spec: 0%	NA	NA
Rayter et al. 1989*	35 patients undergoing elective cholecystectomy (mean age:56 years )	Reference	NA	Sens: 37.5% Spec: 45.5%	NA	NA
Lee et al. 2010	3 pediatric patient cases with spontaneous bile duct perforation (ages 3, 4, and 15 months)	Reference	NA	Sens:50% Spec: NA	NA	Sens:100% Spec: NA
Trerotola et al. 1992	13 patients post-cholecystectomy (mean age: 51 years)	Detection rate  100%	Detection rate  88%	Detection rate  0%	Detection rate  0%	NA

chole = cholescintigraphy; CT = computed tomography; ERCP = endoscopic retrograde cholangiography; MRCP = magnetic resonance cholangiopancreatography; MRI = magnetic resonance imaging; NA = not available; NLR = negative likelihood ratio; PLR = positive likelihood ratio; PPV: positive predictive value, sens = sensitivity; spec = specificity; U/S = ultrasound.

*Calculated using data provided in the article