Diagnostic Accuracy of Ultrasonography in Choledocholithiasis Taking Intraoperative Findings as Gold Standard
Dr.Sanjay Kumar1, Dr Abdul Razaque2, Dr Chakar Tajwidi3, Dr. Asma4, Dr. Sehraan Khalid5, Dr. Uttam Gautam6, Dr. Burhan Rasheed7
1MBBS, FCPS, Assistant Professor, Makran Medical College Turbat Pakistan.
2MBBS FCPS, Assistant Professor, Pir Abdul Qadir Shah Jeelani Institute of Medical Science Gambat Khairpur, Pakistan
3Assistant Professor, MBBS, FCPS, Makran Medical College
4Medical Officer, Shifa International hospital, Islamabad
5King Edward Medical University Lahore, PGR radiology, Mayo Hospital Lahore
6PGR MD Radiology, King Edward Medical University/Mayo Hospital, Lahore
7Assistant professor, Rai medical college Sargodha ABSTRACT
INTRODUCTION: It is very important to find a a non invasive, less time consuming and relatively easy modality, non operator dependent and available even remote areas for the common bile duct stones (choledocolithiasis) in symptomatic patients. Instant diagnosis will lead to prompt decision making for treatment strategies that will ultimately decrease the morbidity.
OBJECTIVE: To determine the diagnostic accuracy of ultrasonography in detection of Choledocholithiasis in suspected patients taking intraoperative findings as gold standard.
STUDY DESIGN: Descriptive Cross sectional Study
SETTING: Department of Radiology, Jinnah postgraduate Medical Center, Karachi DURATION: Six months study from Feb 2020 onwards.
SUBJECTS AND METHODS: All patients with age 30-60 years of either gender having clinically suspected with duration of symptoms of more than or equal to 7 days were enrolled.
The ultrasound was performed and presence of CBD diameter of > 7 mm on US was taken as CBD stones. Presence of CBD stones intra operatively was noted.
RESULTS: Mean age of the patients was 51.29 ±7.03 years. There were 75 (62%) females and 46 (38%) males. Overall diagnostic accuracy of ultrasonography was found to be 89.25%.
Sensitivity was found to be 80.48%, specificity 93.75%, PPV 86.84% and NPV 90.36%.
CONCLUSION: The diagnostic accuracy of ultrasonography was found satisfactory in detection of Choledocholithiasis in suspected patients taking intraoperative findings as gold standard.
KEYWORDS: Choledocholithiasis, ultrasonography, intraoperative findings INTRODUCTION
Gallstone disease is responsible for about 1.8 million ambulatory care visits and more than 700,000 cholecystectomies yearly in the United States.1-
2In Canada, adjusted annual rate of elective cholecystectomy was 260.8 per 100 000 population during the period 1992-2000.3 Gallstones disease is the second most common reason for hospitalization (with an estimated of US$5.8 billion annually), although only 15% of people with gallstones have related symptoms.4-7 One complication is the occurrence of stones stones in the common bile duct.4−7
Stones in the common bile duct (choledocholithiasis) most commonly result from the passage of gallstones through the cystic duct into the common bile duct.
Less frequently, they may originate in the common bile duct itself. Choledocholithiasis can cause biliary obstruction, cholangitis, pancreatitis or secondary biliary cirrhosis in patients who have had the stones for a long time. More than 1 in 10 patients (10%-18%) undergoing cholecystectomy for gallstones have concomitant common bile duct stones,7 and up to 3.8% have symptoms related to choledocholithiasis during the first year after cholecystectomy.8
Patients with asymptomatic bile duct stones exhibit typical signs, such as elevated liver function tests, dilated bile ducts on ultrasound, a history of jaundice, or pancreatitis. The magnitude of asymptomatic bile duct stones is about 10%, but up to 2% of patients show no signs of the disease.9 In a study MRC or ERC was performed because of suspected choledocholithiasis and CBD stones were diagnosed in 45 (30.4%) of the 148 patients.10
The evaluation of common bile duct stones in patients with gallstone disease involves stratifying their probability of having a stone in the common bile duct to: low (<10%), intermediate (10%–
50%) or high (> 50%).11 Many imaging modalities are available for investigating suspected stones in the common bile duct. These include include older techniques such as intravenous Cholangiography and endoscopic retrograde cholangiopancreatography (ERCP) and newer techniques such as magnetic resonance cholangiopancreatography and ultrasonography.
The sensitivity, specificity, positive and negative predictive value of ultrasonography in detecting CBD stones in a study was 65%, 60%, 76.47% and 46.15% respectively.12
The rationale of the study is to generate local data on this topic as no local data is available and to find a non invasive, less time consuming and relatively easy modality, non operator dependent and available even remote areas for the common bile duct stones (choledocolithiasis) in symptomatic patients. Instant diagnosis will lead to prompt decision making for treatment strategies that will ultimately decrease the morbidity.
LITERATURE REVIEW:
Choledocholithiasis is a medical condition that mandates surgical intervention. It may occur in 3% – 10% of patients with cholecystectomy,13 and as high as 14.7% in some series. 14 Generally, the prevalence of asymptomatic bile duct stones is reported between 5.2% and 12%.15
There are several diagnostic approaches for common bile duct (CBD) stones. These include:
laboratory analysis, ultrasonography (US), computed tomography scans (CT scan), magnetic resonance cholangiopancreatography (MRCP), endoscopic ultrasonography (EUS), and endoscopic retrograde cholangiopancreatography (ERCP). Intraoperative cholangiography (IOC) during cholecystectomy can be performed routinely or selectively to diagnose choledocholithiasis.16,17
Nowadays, 2 groups of interventions have a significant role in the management of patients with gallstone and CBD stones: pre- or post-cholecystectomy ERCP with endoscopic sphincterotomy (ES), which is a two-stage procedure, and surgical bile duct clearance and cholecystectomy by single open or laparoscopic surgery (one-stage procedure). Several randomized controlled trials have shown comparable effectiveness of these modalities.18,19
Other methods include electrohydraulic lithotripsy (EHL), extracorporeal shockwave lithotripsy (ESWL), laser lithotripsy and dissolving solutions that are advocated for special conditions.20,21 Although, ERCP and laparoscopic CBD exploration are preferred methods in most centers, open CBD exploration should never be abandoned. Some studies have proposed choledochotomy with primary laparoscopic closure of the CBD which eliminates the need for a T-tube, thus reducing surgical time and postoperative morbidity.22
However, open CBD exploration with T-tube insertion remains the standard procedure for most patients. The management of choledocholithiasis has always been challenging. Nowadays, ERCP has essentially replaced open surgery for safe and effective CBD stone extraction. Open CBD exploration is an important surgical procedure when ERCP fails and expertise for laparoscopic CBD exploration is not available. The optimal method for performing open CBD exploration is unclear.23
The routine use of IOC during laparoscopic cholecystectomy remains controversial.24 Stuart et al. have performed IOC in 348 patients, of which it was abnormal in 17 (5%) cases. However, documented retained stones that existed in 5 patients were removed by CBD exploration or ERCP in that study.25 Mir et al. did not perform IOC, and reported reductions in costs and hospital stay.26
Generally, ERCP is more feasible in this subgroup since postoperative T-tube cholangiography shows the anatomy of the biliary tree and large or impacted stones that have been extracted during surgery. In patients with sepsis due to cholangitis and accompanying diseases, it was
necessary to shorten the time of surgery. In addition, biliary-enteric anastomosis increased the risk of complications. In such cases, the T-tube was inserted following CBD exploration. In cases with CBD diameters less than 12 mm, the T-tube was used because of the high risk for anastomotic stricture27 and subsequent complications. Most authors have preferred insertion of T-tube for CBD drainage, but some centers have utilized transcystic tubes (C-tube) or antegrade stenting with choledochorrhaphy for CBD drainage.28
In patients with residual distal stone, ductal imaging in the postoperative period and provision of an access route for removal of residual CBD stones has been performed.29 The most commonly used choledochoenterostomy is side-toside choledochoduodenostomy, usually in the setting of a dilated CBD.30
In cases where duodenal anastomosis was impossible, choledochojejunostomy was performed.
Currently, many centers use laparoscopy for CBD surgeries. Ex-pert surgical teams have reported a CBD clearance rate of about 97%.23 The morbidity rate has been reported to be 9.5%
and retained stone rate of 2.7% for exploratory laparoscopic CBD.24 METHODOLOGY:
Sample Size:
Prevalence of choledocolithiasis10=30.4%
Confidence level=95%
Bond on error=10% for specificity and 13% for sensitivity Sensitivity12=65%
Specificity12=60%
Sample size=121 symptomatic patients Sampling Technique:
Non Probability Consecutive sampling SAMPLE SELECTION
Inclusion Criteria
● Clinically suspected Patients diagnosed as defined in operational definition)
● Duration of symptoms of more than or equal to 7 days
● Age 30-60 years
● Either gender
Exclusion Criteria
Patients having following conditions were excluded from the study
● Carcinoma head of pancreas
● Periampullary carcinoma
● CBD strictures
● Cholangiocarcinoma
DATA COLLECTION
The study was conducted post approval of ethical review committee of the institute. Clinically suspected Patients diagnosed as defined in operational definition) meeting the inclusion criteria attending the out-patient department of JPMC, Karachi was enrolled in the study. The purpose and procedure of the study was explained, confidentiality was ensured and Informed consent was taken from the patient for inclusion in the study. The ultrasound was performed by the sonologist having more than five years of experience. Presence of CBD diameter of > 7 mm on US was taken as CBD stones. All patients will undergo surgery performed by a consultant having more than 5 years year of experience. Presence of CBD stones intra operatively was noted by the researcher. Demographics of the patients like age, gender, BMI along with US and intraoperative findings was entered in the proforma by the researcher.
DATA ANALYSIS
Data was entered and analyzed on SPSS version 20 for windows. Frequency and percentages was estimated for gender, US and intraoperative findings. Mean±SD was calculated for age, duration of symptoms and BMI of the patients. Sensitivity, specificity, PPV and NPV was calculated for US taking intra operative findings as gold standard. Stratification of age, gender and BMI was done to control effect modifiers.
RESULTS:
The age ≤45 and comparison of ultrasound findings with intraoperative findings is showed below:
n=40
US Findings
Intraoperative Finding p-value
Yes No Total
Yes 11 2 13 0.001
No 2 25 27
Total 13 27 40
Sensitivity = (11÷ 13) × 100 = 84.61%
Specificity = (25 ÷ 27) × 100 = 92.59%
Positive predictive value = (11÷ 13) × 100 = 84.61%
Negative predictive value = (25÷27) × 100 = 92.59%
Diagnostic Accuracy= (11+25÷ 11+2+2+25) = 90%
The age >45 and comparison of ultrasound findings with intraoperative findings is showed below:
n=81
US Findings
Intraoperative Finding p-value
Yes No Total
Yes 22 3 25 0.001
No 6 50 56
Total 28 53 81
Sensitivity = (22÷ 28) × 100 = 78.57%
Specificity = (50 ÷ 53) × 100 = 94.33%
Positive predictive value = (22÷ 25) × 100 = 88%
Negative predictive value = (50÷56) × 100 = 89.28%
Diagnostic Accuracy= (22+50÷ 22+3+6+50) = 88.89%
Male gender and comparison of ultrasound findings with intraoperative findings is showed below:
n=46
Intraoperative Finding p-value
US Findings Yes No Total
Yes 13 5 18 0.001
No 1 27 28
Total 14 32 46
Sensitivity = (13÷ 14) × 100 = 92.85%
Specificity = (27 ÷ 32) × 100 = 84.37%
Positive predictive value = (13÷ 18) × 100 = 72.22%
Negative predictive value = (27÷28) × 100 = 96.42%
Diagnostic Accuracy= (13+27÷ 13+5+1+27) = 86.95%
Female gender and comparison of ultrasound findings with intraoperative findings is showed below:
n=75
US Findings
Intraoperative Finding p-value
Yes No Total
Yes 20 0 20 0.001
No 7 48 55
Total 27 48 75
Sensitivity = (20÷ 27) × 100 = 74.07%
Specificity = (48 ÷ 48) × 100 = 100%
Positive predictive value = (20÷ 20) × 100 = 100%
Negative predictive value = (48÷55) × 100 = 87.27%
Diagnostic Accuracy= (20+48÷ 20+48+0+7) = 90.66%
≤30 BMI and comparison of ultrasound findings with intraoperative findings is showed below:
n=38
US Findings
Intraoperative Finding p-value
Yes No Total
Yes 10 1 11 0.001
No 1 26 27
Total 11 27 38
Sensitivity = (10÷ 11) × 100 = 90.90%
Specificity = (26 ÷ 27) × 100 = 96.29%
Positive predictive value = (10÷ 11) × 100 = 90.90%
Negative predictive value = (26÷27) × 100 = 96.29%
Diagnostic Accuracy= (10+26÷26+10+1+1) = 94.73%
>30 BMI and comparison of ultrasound findings with intraoperative findings is showed below:
n=83
US Findings
Intraoperative Finding p-value
Yes No Total
Yes 23 4 27 0.001
No 7 49 56
Total 30 53 83
Sensitivity = (23÷ 30) × 100 = 76.66%
Specificity = (49 ÷ 53) × 100 = 92.54%
Positive predictive value = (23÷ 27) × 100 = 85.18%
Negative predictive value = (49÷53) × 100 = 92.45%
Diagnostic Accuracy= (23+49÷ 23+49+4+7) = 86.74%
DISCUSSION
Choledocholithiasis can cause biliary obstruction, cholangitis, pancreatitis or secondary biliary cirrhosis in patients who have had the stones for a long time. More than 1 in 10 patients (10%- 18%) undergoing cholecystectomy for gallstones have concomitant common bile duct stones,7 and up to 3.8% have symptoms related to choledocholithiasis during the first year after cholecystectomy.8
Patients with asymptomatic bile duct stones exhibit typical signs, such as elevated liver function tests, dilated bile ducts on ultrasound, a history of jaundice, or pancreatitis. The magnitude of asymptomatic bile duct stones is about 10%, but up to 2% of patients show no signs of the disease.9 In a study MRC or ERC was performed because of suspected choledocholithiasis and CBD stones were diagnosed in 45 (30.4%) of the 148 patients.10
The evaluation of common bile duct stones in patients with gallstone disease involves stratifying their probability of having a stone in the common bile duct to: low (<10%), intermediate (10%–
50%) or high (> 50%).11
Many imaging modalities are available for investigating suspected stones in the common bile duct. These include include older techniques such as intravenous Cholangiography and endoscopic retrograde cholangiopancreatography (ERCP) and newer techniques such as magnetic resonance cholangiopancreatography and ultrasonography.
In our study, overall diagnostic accuracy of ultrasonography was found to be 89.25%. Sensitivity was found to be 80.48%, specificity 93.75%, PPV 86.84% and NPV 90.36%. The sensitivity, specificity, positive and negative predictive value of ultrasonography in detecting CBD stones in a study was 65%, 60%, 76.47% and 46.15% respectively.12
Choledocholithiasis is a medical condition that mandates surgical intervention. It may occur in 3% – 10% of patients with cholecystectomy,13 and as high as 14.7% in some series. 14 Generally, the prevalence of asymptomatic bile duct stones is reported between 5.2% and 12%.15
There are several diagnostic approaches for common bile duct (CBD) stones. These include:
laboratory analysis, ultrasonography (US), computed tomography scans (CT scan), magnetic resonance cholangiopancreatography (MRCP), endoscopic ultrasonography (EUS), and endoscopic retrograde cholangiopancreatography (ERCP). Intraoperative cholangiography (IOC)
during cholecystectomy can be performed routinely or selectively to diagnose choledocholithiasis.16,17
Nowadays, 2 groups of interventions have a significant role in the management of patients with gallstone and CBD stones: pre- or post-cholecystectomy ERCP with endoscopic sphincterotomy (ES), which is a two-stage procedure, and surgical bile duct clearance and cholecystectomy by single open or laparoscopic surgery (one-stage procedure). Several randomized controlled trials have shown comparable effectiveness of these modalities.18,19
CONCLUSION
The diagnostic accuracy of ultrasonography was found satisfactory in detection of Choledocholithiasis in suspected patients taking intraoperative findings as gold standard.
REFERENCES:
1. NIH state-of-the-science statement on endoscopic retrograde
cholangiopancreatography (ERCP) for dia-nosis and therapy.NIH Consens State Sci Statements 2002;19:1-26.
2. Everhart JE, Ruhl CE. Burden of digestive diseases in the UnitedStates. Part III: liver, bili ary tract, and pancreas. Gastroenterology. 2009;136:1134-44.
3. Urbach DR, Stukel TA. Rate of elective cholecystectomy and the incidence of severe gallstone disease. CMAJ. 2005;172:1015-9.
4. Tse F, Barkun JS, Barkun AN. The elective evaluation of patients with suspected choledo cholithiasis undergoing laparoscopic cholecystectomy. Gastrointest Endosc.
2004;60:437-48.
5. Abboud PA, Malet PF, Berlin JA, et al. Predictors of common bile duct stones prior to cholecystectomy: a meta-analysis. Gastrointest Endosc.
1996;44:450-5.
6. Liu TH, Consorti ET, Kawashima A, et al. Patient evaluation and management with selective use of magnetic resonance cholangiography and endoscopic retrograde cholangiopancreatography before laparoscopic cholecystectomy. Ann surg. 2001:33-40.
7. Martin DJ, Vernon DR, Toouli J. Surgical versus endoscopic treatment of bile duct stones treatment of bile duct stones. Cochrane Database Syst Rev 2006; CD003327
8. Järhult J. Is preoperative evaluation of the biliary tree necessary inuncomplicated 9. Gallstone disease? Results of a randomized trial. Scand J Surg. 2005;94:31-3.
10. Rosseland AR, Glomsaker TB. Asymptomatic common bile duct stones. Eur J Gastroenterol Hepatol. 2000 Nov;12(11):1171-3.
11. Kim YJ, Kim MJ, Kim KW, Chung JB, Lee WJ, Kim JH, et al. Preoperative evaluation of common bile duct stones in patients with gallstone disease. AJR Am J Roentgenol.
2005 Jun;184(6):1854-9.
12. Maple JT, Ben-Menachem T, Anderson MA, et al. The role of endoscopy in the evaluation of suspected choledocholithiasis. Gastrointest Endosc 2010;71:1-9.
13. Mandelia A, Gupta AK, Verma DK, Sharma S. The Value of Magnetic Resonance Cholangio-Pancreatography (MRCP) in the Detection of Choledocholithiasis. J Clin Diagn Res. 2013 Sep;7(9):1941-5.
14. Schirmer BD, Witers KL, Edlich RF. Choledocholithiasis and cholecystitis. J Long Term Eff Med Implants. 2005; 15: 329 – 338.
15. Riciarel R, Islam S, Canete JJ, Avcand PL, Stoker ME. Effectiveness and long term results of laparoscopic common bile duct exploration. Surg Endoscopy. 2003; 17: 19 – 22.
16. Rosseland AR, Glomsaker TB. Asymptomatic common bile duct stones. Eur J Gastrentrol Hepatol. 2000; 12: 1171 – 1173.
17. Freitas M, Bell R, Duffy A. Choledocholithiasis: Evolving standards for diagnosis and managements. World J of Gastroentrology. 2006; 12: 3162 – 3167.
18. Schwarz J, Simsa J, Pazdirek F. Our experience with preoperative choledochoscopy.
Rozhl Chir. 2007;86(4)180 – 183.
19. Clayton ESJ, Connor S, Alexakis N, Leandros E. Meta analysis of endoscopy and surgery versus surgery alone for common bile duct stones with the gallbladder in situ. Br J Surg.
2006; 93: 1185 – 1191.
20. Martin DJ, Vernon DR, Toouli J. Surgical versus endoscopic treatment of bile duct stones (Review). Cochrane Database Syst Rev. 2006;19(2):CD003327.
21. Caddy GR, Tham TC. Symptoms, diagnosis and endoscopic management of common bile duct stones. Best Practice & Research Clinical Gastroenterology. 2006;20:1085 – 1101.
22. Evans AJ, Branch MS. The recalcitrant bile duct stone. Techniques in Gastrointestinal Endoscopy. 2007; 9: 104 – 113.
23. Ahmed I, Pradhan C, Beckingham IJ, Brooks AJ, Rowlands BJ, Lobo DN. Is a T-tube necessary after common bile duct exploration? World J Surg. 2008; DOI 10.1007/s00268-008-9475-2
24. Gurusamy KS, Samrai K. Primary closure versus T-tube drainage after open common bile duct exploration. Cochrane Database Syst Rev. 2007; 1: CD005640.
25. Ciulla A, Aqnello G, Tomasello G, Castronovo G, Maiorana AM, Genova G. The intraoperative cholangiography during videolaparoscopic cholecystectomy. What is its role? Results of a non randomized study. Ann Ital Chir. 2007;78(2):85 – 89.
26. Stuart AS, Simpson T, Alvord L, Williams M. Routine intraoperative laparoscopic cholangiography. Am J Surgery. 1998; 176: 632 – 637.
27. Mir IS, Mohsin M, Kirmani O, Majid T, Wani K, Hassan MU, et al. Is intraoperative cholangiography necessary during laparoscopic cholecystectomy? A multicentre rural experience from a developing world country. World J Gastroenterol. 2007;13(33):4493 – 4497.
28. Ramirez P, Parrilla P, Bueno FS, Abad JMP, Muelas MS, Candel MF, et al.
Choledochoduodenostomy and sphincterotomy in the treatment of choledocholithiasis. Br J Surg. 1994; 81: 121 – 123.
29. Isla AM, Griniatsos J, Karvounis E, Arbuckle JD. Advantages of laparoscopic stented choledochorrhaphy over T-tube placement. Br J Surg. 2004; 91: 862 – 866.
30. Petelin JB. Laparoscopic common bile duct exploration. Surg Endosc. 2003; 17: 1705 – 1715.
31. Hungness ES, Soper NJ. Management of common bile duct stones. J Gastrointestinal Surgery. 2006;10(6):612 – 619.
