Laparoscopic Cystic Duct Balloon Dilation Combined with Transcystic Stone Extraction for the Treatment of Choledocholithiasis

Summary

This protocol standardizes the surgical workflow for laparoscopic cystic duct balloon dilation combined with laparoscopic transcystic common bile duct exploration (LTCBDE). Its core objective is to overcome the anatomical constraints of the cystic duct via balloon dilation, thereby facilitating safe, minimally invasive clearance of choledocholithiasis.

Abstract

Common bile duct stones (CBDS) are a common benign disorder of the digestive system. Severe cases can be complicated by acute cholangitis or biliary pancreatitis, posing a potentially life-threatening risk to patients. Currently, the primary minimally invasive therapeutic modalities include endoscopic retrograde cholangiopancreatography (ERCP), laparoscopic choledochotomy for common bile duct exploration (LCCBDE), and laparoscopic transcystic common bile duct exploration (LTCBDE). However, ERCP requires incision of the duodenal papilla, which may irreversibly impair the sphincter of Oddi and increase the risk of retrograde biliary infections. Conversely, LCCBDE traditionally requires choledochotomy and T-tube placement, which not only elevates the risks of bile leakage and biliary stricture but also compromises the patient's quality of life. Although LTCBDE preserves the physiological integrity of the biliary tract, the conventional procedure is often technically demanding due to anatomical variations, such as a narrow cystic duct. To overcome this technical bottleneck, this study introduced laparoscopic cystic duct balloon dilation combined with LTCBDE to mechanically expand the narrow cystic duct. The authors retrospectively reviewed the clinical data of patients who underwent these three surgical modalities at the institution between 2018 and 2024. The results demonstrated that balloon dilation combined with the LTCBDE group showed favorable outcomes, including a shorter hospital stay, lower total hospitalization costs, and a low incidence of postoperative complications. These findings indicate that this modified approach appears to be a safe, effective, and cost-effective alternative strategy for the management of low-to-moderate complexity choledocholithiasis.

Introduction

Common bile duct stones (CBDS) are among the most prevalent benign disorders of the digestive system. In the general population, the prevalence of cholelithiasis ranges from 10–15%¹, and approximately 10–20% of patients with a history of gallstones have concomitant CBDS². The incidence of CBDS increases with age, rendering it particularly prevalent among the elderly³. The pathogenesis of CBDS is multifactorial, involving abnormal bile composition, biliary obstruction, and biliary infection⁴. Although some patients remain asymptomatic, typical symptomatic manifestations include right upper quadrant pain, jaundice, and fever. Severe cases may be complicated by acute cholangitis or biliary pancreatitis, potentially posing life-threatening risks to patients⁵.

With advancements in medical technology, the therapeutic strategies for CBDS have continuously evolved. Historically, open surgery was the mainstay of treatment; however, due to significant surgical trauma and prolonged recovery times, it has been largely superseded by minimally invasive approaches⁶. Currently, the mainstream minimally invasive modalities in clinical practice primarily include endoscopic retrograde cholangiopancreatography (ERCP) and laparoscopic common bile duct exploration (LCBDE). Specifically, LCBDE can be further categorized into laparoscopic choledochotomy for common bile duct exploration (LCCBDE) and laparoscopic transcystic common bile duct exploration (LTCBDE)⁷.

LTCBDE is a minimally invasive technique for managing cholecystolithiasis complicated by CBDS, achieving a stone clearance rate of 85–95%⁸. This approach offers several significant advantages. First, it preserves the anatomical integrity of the biliary tract and the physiological function of the sphincter of Oddi⁹. Second, it circumvents the complications associated with choledochotomy and T-tube placement, such as T-tube dislodgement, biliary stricture, and fluid and electrolyte imbalance¹⁰. Finally, LTCBDE has been shown to facilitate enhanced postoperative recovery, shorten the length of hospital stay, and reduce overall hospitalization costs⁸.

However, conventional LTCBDE is often technically demanding due to anatomical variations, particularly a narrow cystic duct⁹. The modified approach evaluated in this study—laparoscopic cystic duct balloon dilation combined with LTCBDE—provides a viable alternative to bypass these anatomical constraints. Previous studies have indicated that controlled balloon micro-dilation can effectively expand the cystic duct with a favorable safety profile, effectively broadening the indications for transcystic exploration in patients who might otherwise require choledochotomy due to ductal limitations^11,12. Specifically, the institutional experience suggests that this technique is suitable for patients presenting with choledocholithiasis who meet specific anatomical prerequisites: a cystic duct diameter of ≥ 3 mm, a common bile duct stone diameter of <1 cm, and fewer than 10 stones. Consequently, this modification may serve as a feasible alternative approach for the minimally invasive management of selected patients with low-to-moderate complexity choledocholithiasis, aiming to achieve safe and effective biliary clearance as the primary endpoint, with its procedural success supported by representative measurable outcomes including complete stone clearance rates, postoperative complication incidences, length of hospital stay, and total hospitalization costs.

Protocol

The relevant surgeries were approved by the Institutional Review Board (Ethics Committee) of the Second Affiliated Hospital of Soochow University (No. JD-HG-2025-084). All included patients provided written informed consent prior to undergoing the surgical procedures. The primary surgical consumables required for the procedure are listed in the Table of Materials.

1. Inclusion criteria

1. Include patients age ≥ 18 years, diagnosed with gallbladder stones combined with common bile duct stones via abdominal Doppler ultrasound, CT, or magnetic resonance cholangiopancreatography (MRCP); stone diameter < 1 cm; number of stones < 10; cystic duct diameter ≥ 3 mm.

2. Exclusion criteria

1. Exclude patients with occluded or extremely thin cystic ducts impassable by the choledochoscope; fragile cystic ducts prone to tearing; giant or cast stones in the common bile duct; concomitant intrahepatic bile duct stones; concomitant other malignancies; severe preoperative coagulation dysfunction; history of biliary surgery or biliary tract deformation.

3. Preoperative preparation

1. Complete abdominal Doppler ultrasound, CT, or MRCP to verify and confirm the diameter of the common bile duct stones (<1 cm) and the number of stones (<10).
   NOTE: Focus on measuring the diameter of the cystic duct to ensure it is ≥3 mm to guarantee the smooth entry of the balloon and ultra-slim choledochoscope.
2. Perform routine blood tests and liver/kidney function tests upon the patient's admission.
3. Focus on evaluating the baseline values of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) to compare with postoperative recovery.
4. Conduct a coagulation function screening to detect and correct coagulation dysfunction.
5. Perform electrolyte tests, blood typing, and an electrocardiogram to ensure the patient has sufficient surgical tolerance.
6. Administer prophylactic or therapeutic antibiotics to patients with fever from cholangitis or jaundice.
7. Administer hepatoprotective drugs for symptomatic treatment if baseline ALT or AST levels exceed twice the upper limit of normal.
8. Enforce routine preoperative fasting and fluid restriction to prevent aspiration under general anesthesia.
9. Perform routine skin preparation and cleaning of the abdominal surgical area. Obtain written surgical informed consent after fully informing the patient or their family.

4. Surgical procedure

1. Anesthesia, positioning, and laparoscopic access
   1. Administer routine general anesthesia with endotracheal intubation after the patient enters the operating room. Induce anesthesia via intravenous injection using the following targeted regimen: propofol (1.5–2.5 mg/kg), sufentanil (0.1–0.5 µg/kg), and rocuronium bromide (0.6–0.9 mg/kg).
   2. Place the patient in a supine position after successful anesthesia.
   3. Adjust the position to a 15° to 20° reverse Trendelenburg and 10° to 15° left-tilt orientation when the transverse colon or duodenum obscures the operative field, to facilitate downward bowel movement and expose the subhepatic area (Figure 1A).
   4. Disinfect the abdominal surgical area using iodophor. Apply sterile surgical drapes strictly following aseptic principles.
   5. Make an incision near the umbilicus. Establish a CO₂ pneumoperitoneum using the Veress needle puncture method.
      CAUTION: Immediately upon removal, dispose of the Veress needle directly into a sharps container to prevent accidental needlestick injuries.
   6. Maintain intra-abdominal pressure at 14 mmHg during the surgery to ensure adequate exposure of the surgical field, while closely monitoring the patient to avoid hemodynamic compromise.
   7. Insert trocars using the routine four-port method (Figure 1B): Observation port: Insert a 10 mm trocar and a 30° laparoscope through the periumbilical incision.
   8. Primary operating port: Insert a 10 mm trocar below the xiphoid process as the surgeon's main instrument channel.
   9. Auxiliary operating port: Puncture and insert a 5 mm trocar 3 cm below the right costal margin under direct vision as the operating channel for the choledochoscope and related instruments.
   10. Traction port: Insert a 5 mm trocar below the right costal margin at the anterior axillary line to assist in organ traction and exposure.
       CAUTION: To prevent percutaneous injuries and biological exposure from sharp instruments (e.g., Veress needles, trocars) and bodily fluids, the surgical team must wear sterile PPE (gowns, masks, gloves) and transfer all sharps exclusively within a designated neutral zone.
2. Calot's triangle dissection and cystic duct mobilization
   1. Lift the ampulla or fundus of the gallbladder using disposable electrosurgical grasping forceps. Pull it outward to the right to create tension in Calot's triangle (Figure 2A).
   2. Carefully mobilize the anterior and posterior serosa of the gallbladder triangle and loose connective tissue using a disposable electrosurgical hook (set to 40 W for cutting and 40 W for coagulation).
      CAUTION: To mitigate electrosurgical hazards, ensure proper patient grounding and verify instrument insulation. Furthermore, accurate identification of the cystic, common hepatic, and common bile ducts is crucial to prevent inadvertent thermal injury to the biliary tract and adjacent viscera.
   3. Dissect the cystic artery clearly. Clip it with a disposable, absorbable ligating clip, then transect it (Figure 2B). Dissect the gallbladder from the gallbladder bed of the liver. Achieve strict hemostasis during dissection and protect the liver bed tissue.
      ​NOTE: Do not excise the gallbladder at this point. Use the gallbladder as a natural traction point later to provide stable support for cystic duct dilation and scope insertion.
   4. Clip the distal end of the cystic duct with a polymer ligation clip (Figure 2C). Continue to dissect the mobilized cystic duct proximally until its junction with the common bile duct.
   5. Make a transverse incision through approximately half the circumference of the anterior wall of the cystic duct using scissors, perpendicularly to the cystic duct, at a proximal position approximately 1.0 cm from the junction of the cystic duct and the common bile duct.
   6. Then, make a 0.2 cm T-shaped incision proximally parallel to the cystic duct (Figure 2D).
3. Balloon dilation and ultra-slim choledochoscopy exploration
   1. Insert a guidewire through the right subcostal trocar. Insert the disposable guidewire into the common bile duct through the cystic duct incision under the direct vision of the disposable electrosurgical dissecting forceps (Figure 3A).
   2. Introduce the disposable cylindrical dilation catheter (specification: 8 mm × 4 cm) over the guidewire. Position it across the junction of the cystic duct and the common bile duct.
   3. Inject sterile normal saline into the balloon via the analog inflation device to perform gradual pressurized dilation. Stop pressurization when the pressure reaches 5 atm and maintain it for 10 min (Figure 3B). Subsequently, depressurize and withdraw the balloon.
      NOTE: Retain the guidewire within the bile duct lumen as a track. Visually inspect the cystic duct incision. Confirm that the ductal orifice is visibly widened and structurally intact without tearing.
   4. Advance the ultra-slim choledochoscope through the right subcostal trocar over the retained guidewire (Figure 3C).
   5. Insert the choledochoscope into the common bile duct through the cystic duct using the support provided by the trocar.
   6. Explore the lower segment of the common bile duct first after insertion (Figure 4A). Snare and extract any identified stones using a disposable stone extraction basket (Figure 3D, Figure 4B).
   7. Push tiny residual stone fragments into the duodenum using the choledochoscope and the thrust of the flushing fluid.
      NOTE: Ensure successful scope passage with clear visualization of the common bile duct lumen and the ampulla.
   8. Advance the ultra-slim choledochoscope downwards again through the duodenal papilla (sphincter of Oddi) into the duodenal cavity (Figure 4C).
   9. Confirm the papillary function and tract patency. Slowly withdraw the scope. Comprehensively observe the common bile duct, common hepatic duct, and left/right hepatic ducts (Figure 4D) until no distinct stones remain.
4. Specimen retrieval and abdominal drainage
   1. Withdraw the choledochoscope after exploring and confirming the absence of residual stones. Ligate the cystic duct stump using 4-0 absorbable sutures or absorbable clips (Figure 5A).
   2. Apply an additional polymer ligation clip if visual inspection reveals incomplete closure or bile seepage after the initial clip. Subsequently, transect the cystic duct using scissors (Figure 5B) and remove the gallbladder.
   3. Carefully inspect the gallbladder bed, cystic duct stump, and the running area of the cystic artery. Ensure no active bleeding or bile leakage (Figure 5C).
   4. Insert a specimen bag through the trocar port. Place the dissected gallbladder and the extracted stones completely into the bag and retrieve them from the abdominal cavity (Figure 5D).
      CAUTION: To prevent biological exposure from extracted specimens (e.g., tissue, gallstones, biliary fluids), the surgical team must maintain standard infection-control precautions and continue wearing sterile PPE (gowns, masks, and gloves) during retrieval, transfer, and postoperative cleanup.
   5. Flush the right subhepatic space and gallbladder bed with normal saline until the flushing fluid becomes completely clear (Figure 5E).
      NOTE: Continue irrigation (approximately 500–1000 mL of normal saline) until the aspiration fluid becomes completely clear. Ensure no active bleeding or bile leakage is observed.
   6. Evaluate the patient's intraoperative local inflammation (e.g., presence of acute inflammation or severe congestion and edema).
   7. Based strictly on this clinical judgment, place a silicone drainage tube in the right subhepatic space if intraoperative observation reveals acute purulent inflammation, severe tissue congestion and edema, or persistent minor oozing from the gallbladder bed (Figure 5F).
   8. Route the drainage tube out through the right abdominal wall puncture hole and secure it properly.
   9. Deflate the pneumoperitoneum. Close each trocar puncture hole layer by layer after accurately counting the instruments. Cover the wounds with sterile dressings. Send all surgical specimens for pathological examination upon completion of the surgery.
      CAUTION: Segregate and dispose of all surgical waste streams in strict accordance with institutional biosafety procedures. Discard all remaining sharps (e.g., needles, trocars, electrosurgical scissors) into designated sharps containers. Dispose of all biohazardous waste, including blood-soaked gauzes, surgical drapes, and the disposable cylindrical dilation catheter, into clearly labeled yellow biohazard bags.

5. Postoperative management

1. Monitor vital signs routinely post-surgery. Allow the patient oral intake of a small amount of warm water after waking from general anesthesia without gastrointestinal adverse reactions.
   1. Transition the patient gradually to a low-fat semi-liquid diet after the restoration of bowel sounds.
   2. Encourage the patient to ambulate as early as postoperative day 1 to promote gastrointestinal function recovery and prevent deep vein thrombosis in the lower extremities.
2. Closely observe the drainage volume, color, and properties of the drainage tube in the right subhepatic space.
   1. Monitor for postoperative bleeding and bile leakage.
   2. Remove the drainage tube safely around postoperative day 3 if the drainage fluid is clear or pale bloody, the daily volume is less than 20 mL, and the patient shows no fever or signs of peritoneal irritation.
3. Recheck blood biochemical indicators routinely post-surgery.
   1. Focus on monitoring ALT and AST to evaluate the recovery of liver function.
   2. Based on the surgeon's clinical judgment regarding intraoperative biliary inflammation, administer appropriate antibiotics to prevent cholangitis. Provide routine hepatoprotective drugs for supportive treatment.
4. Closely monitor symptoms such as abdominal pain, fever, and jaundice during daily rounds.
   1. Discharge the patient once vital signs are stable and laboratory indicators are normal.
   2. Instruct the patient to maintain a low-fat diet. Schedule regular follow-up abdominal ultrasounds and liver function tests at 1, 3, 6, and 12 months post-surgery to confirm the absence of residual stones or recurrence.

6. Data analysis

1. Explicitly define the primary and secondary endpoints to systematically evaluate the clinical efficacy, safety, and economic feasibility of the three surgical modalities.
2. Designate the complete stone clearance rate and the overall incidence of postoperative complications as the co-primary endpoints.
3. Define complete stone clearance as the absence of residual common bile duct stones, and confirm this via postoperative imaging or direct choledochoscopic visualization.
4. Assess the overall complication rate by including any major adverse events occurring prior to discharge or during the follow-up period, specifically hemorrhage, bile leakage, biliary stricture, and acute cholangitis.
5. Establish the secondary endpoints using parameters that reflect postoperative enhanced recovery and health economics.
6. Specifically, evaluate postoperative liver function recovery by measuring serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, alongside the length of hospital stay and total hospitalization costs.
7. For the hospitalization costs, strictly define total hospitalization costs as the actual direct medical expenses incurred exclusively during the index admission, and exclude any subsequent readmission costs.
8. Include within this comprehensive metric the surgical and procedural fees, anesthesia, ward accommodations, nursing care, pharmaceuticals, and the explicit costs of all specialized medical devices utilized during the interventions (e.g., disposable cylindrical balloon dilation catheters, ultra-slim choledochoscopes, and ERCP-specific consumables).
9. To reflect real-world clinical expenditures, report the costs in Chinese Yuan (RMB) based on the unadjusted actual billing values at the time of patient discharge (spanning 2018–2024), without applying retrospective inflation adjustments.
10. To ensure objective and standardized safety reporting, define and grade postoperative complications using internationally recognized diagnostic criteria.
11. Specifically, define postoperative bile leakage according to the criteria set by the international study group of liver surgery (ISGLS)¹³.
12. Diagnose acute cholangitis based on the Tokyo Guidelines 2018 (TG18)¹⁴. Define postoperative or post-ERCP acute pancreatitis utilizing standardized consensus guidelines, including the Cotton criteria¹⁵ and the revised Atlanta classification¹⁶.
13. Identify other adverse events, such as postoperative hemorrhage and biliary stricture, through a combination of rigorous clinical, laboratory, and imaging evaluations.
14. Perform all statistical analyses using SPSS version 27.0. Present continuous variables adhering to a normal distribution as mean ± standard deviation (SD), and compare them across the three groups using one-way analysis of variance (ANOVA).
15. Use a two-tailed independent Student's t-test when comparing only two groups. Present continuous variables that exhibit skewed distributions as the median and interquartile range (IQR), and analyze them using the Kruskal-Wallis test.
16. Express categorical variables as frequencies and percentages, and assess differences among groups using Pearson's chi-squared test, or Fisher's exact test when expected cell counts are less than 5.
17. Employ multivariable regression models to account for potential confounding factors arising from baseline imbalances. Use multiple linear regression to analyze continuous outcomes and apply multivariable logistic regression to analyze categorical outcomes.
18. Systematically adjust these models for predefined baseline covariates, including patient age, history of comorbidities, common bile duct (CBD) diameter, stone size, and the number of stones. Consider a two-sided p-value of < 0.05 as statistically significant.

Results

To illustrate the representative clinical performance of this modified method, clinical data from patients who underwent surgery for CBDS at the Second Affiliated Hospital of Soochow University between January 2018 and December 2024 were retrospectively collected. The detailed patient selection process is illustrated in the flowchart (Figure 6). A total of 310 patients were included in the study: 40 patients underwent balloon dilation combined with LTCBDE, 70 received ERCP alone (without con...

Discussion

With the evolution of minimally invasive techniques, the management of CBDS has transitioned from traditional open surgery to comprehensive therapeutic modalities predominantly involving endoscopic and laparoscopic approaches⁶. Currently, the most widely utilized clinical strategies include ERCP, LCCBDE, and LTCBDE⁷. However, ERCP requires an endoscopic sphincterotomy (incision of the duodenal papilla), which can irreversibly impair the function of the sphincter of Oddi, th...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Absorbable suture	COVIDIEN	4-0 VLOCL0603	-
Analog inflation device	MERIT MEDICAL	IN4130	-
Ciprofol	Haisco	H20213723	-
Disposable absorbable ligating clip	KANGJI	KJ-XJZ02L	-
Disposable cylindrical dilation catheter	JIUHONG	JHY-BD-08-40-110-A	8 mm × 4 cm
Disposable electrosurgical dissecting forcep	KANGJI	KJ-FL0205WT	5 mm × 330 mm
Disposable electrosurgical grasping forcep	KANGJI	KJ-ZQ0205	5 mm × 330 mm
Disposable electrosurgical hook	KANGJI	KJ-DN0205G	5 mm × 330 mm
Disposable electrosurgical scissor	KANGJI	KJ-JD0205W	5 mm × 330 mm
Disposable guidewire	JIUHONG	JHY-GW-80-150-C1	-
Disposable stone extraction basket	COOK	NCT4-017115	-
Hepatoprotective drug	CHIATAI TIANQING	H20051942	Magnesium Isoglycyrrhizinate Injection
Iodophor	LIKANG	31005102	500 mL
Laparoscope	STORZ	26003BA	30°, 10 mm
Normal saline	OTSUKA	H12020026	500 mL
Polymer ligation clip	SINOLINKS	LC-2-3	-
Prophylactic or therapeutic antibiotic	FUAN	H20123389	Cefmetazole Sodium for Injection
Rocuronium bromide	LUNAN	H20244041	-
Silicone drainage tube	CHANGER	419280	-
Specimen bag	WELL LEAD	20172061844	B type, 550 mL
SPSS Statistics	IBM	Version 27.0	-
Sterile surgical drape	AOJIAN	ASQ-69	-
Sufentanil	Humanwell	H20237165	-
Trocar	ANKER	AKCM10×100-10.8	-
Ultra-slim choledochoscope	INNOVEX	CS50H-20EU	-
Veress needle	ANKER	AKCM10×100-10.8	-