Laparoscopic Transcystic Common Bile Duct Exploration: T-Shaped Incision of Cystic Duct with FREDDY Laser Lithotripsy

Abstract

Objectives:

Optimal laparoscopic techniques for management of gallstones concomitant with common bile duct (CBD) stones remain under debate. The aim of this study was to evaluate a novel approach to managing gallstones concomitant with large or impacted CBD stones through a modified laparoscopic transcystic CBD exploration (LTCBDE) with frequency-doubled double-pulse neodymium:YAG (FREDDY) laser lithotripsy.

Materials and Methods:

This retrospective review includes 32 consecutive patients with gallstones concomitant with large or impacted CBD stones who were offered LTCBDE with FREDDY laser lithotripsy between June 2012 and December 2014. Demographic, perioperative, and follow-up data were collected and analyzed retrospectively.

Results:

CBD stone clearance was achieved for all patients. There were 13 males and 19 females, among whom there were three patients with a history of abdominal surgery. The diameter of the CBD ranged from 10 to 20 (mean 15.1) mm, and the number of CBD stones ranged from 1 to 5. CBD stones ranged in diameter from 9 to 18 (mean 11.7) mm and 9 patients had stones that were impacted in the CBD. The mean operative time was 123 ± 18 minutes with a range of 72 to 155 minutes. The mean length of postoperative hospital stay was 5.3 (range 4–7) days. All patients recovered normally without morbidity or mortality.

Conclusions:

The modified LTCBDE with a T-shaped incision of the cystic duct and FREDDY laser lithotripsy is a safe and effective means of managing gallstones concomitant with large or impacted CBD stones.

Introduction

Common bile duct (CBD) stones occur in up to 15% of patients with symptomatic gallstones or acute cholecystitis.¹ Symptomatic CBD stones can lead to obstructive jaundice, cholangitis, secondary biliary cirrhosis, or pancreatitis. With continual improvement in endoscopic and laparoscopic techniques, endoscopic retrograde cholangiopancreatography (ERCP), along with laparoscopic cholecystectomy (LC), and laparoscopic CBD exploration (LCBDE) with LC are preferred for the majority of patients diagnosed as having concomitant gallstones and CBD stones.^2–5 Randomized clinical trials have concluded that there is no statistically significant difference in the success rate of CBD stone clearance, morbidity, or mortality between ERCP and LCBDE in selected patients.^6–8 However, the short-term and long-term adverse events pertaining to ERCP include post-ERCP pancreatitis, sphincter of Oddi dysfunction, and ERCP-related hemorrhage or perforation.⁹ Furthermore, unsuccessful ERCP may cause severe periampullary inflammation that obliterates the papillary orifice or may precipitate iatrogenic complications that lead to higher inpatient mortality.^10–11 LCBDE is safe and effective for the management of bile duct stones without the ERCP-related complications. As a one-stage approach, LCBDE can be performed either through the cystic duct or by choledochotomy. Moreover, laparoscopic transcystic CBD exploration (LTCBDE) has the advantages of protecting the integrity of the CBD, obviating suture repair after choledochotomy, preserving the function of the sphincter of Oddi, faster postoperative recovery, and shorter hospital stay.⁷

However, for clearing large or impacted CBD stones, standard endoscopic or laparoscopic procedures are challenging or impossible. Although multiple studies of LTCBDE with technical modifications have been reported and applied, the optimal technique has not been determined to date.^3,12,13

The frequency-doubled double-pulse neodymium:YAG (FREDDY) laser is a newly developed short-pulse, double frequency, and economical laser with wavelengths of 532 nm and 1064 nm. This laser was designed specifically for endoscopic or laparoscopic lithotripsy and has been used successfully for the treatment of difficult bile duct stones in ERCP or open surgery when the traditional methods failed.^14–18 To date, FREDDY laser lithotripsy has yet to be combined with LTCBDE. In this study, we aimed to evaluate the safety and efficacy of a modified LTCBDE with FREDDY laser lithotripsy for management of gallstones concomitant with large or impacted CBD stones.

Materials and Methods

Patients and clinical data

This retrospective review included 32 patients who consecutively underwent LTCBDE combined with FREDDY laser lithotripsy between June 2012 and December 2014 in the Second Affiliated Hospital of Nan Chang University. Patients with gallstones and symptoms or laboratory abnormalities consistent with CBD stones, including obstructive jaundice; raised levels of alkaline phosphatase (ALP) and/or gamma-glutamyl transferase (GGT); CBD diameter of more than 8 mm; CBD stones diagnosed by abdominal ultrasound, CT scan, or magnetic resonance cholangiopancreatography; repeated biliary colic and cholangitis; previous history of obstructive jaundice; and gallstone pancreatitis were included. Patients with hepatolithiasis, Mirizzi syndrome, and suspected bile duct cancer were excluded. Clinical data regarding demographic characteristics and perioperative and follow-up findings were collected and analyzed retrospectively.

Operative techniques

Patients were under general anesthesia in the supine position. Pneumoperitoneum was established. LTCBDE was performed using a 4-trocar technique (Fig. 1). The first 10-mm trocar (A) was introduced below the umbilicus for insufflation of carbon dioxide at 12–14 mm Hg (1 mm Hg = 0.133 kPa) and insertion of the 30° angled laparoscope (Karl Storze, Tuttlingen, Germany). Three more trocars were placed under direct vision: a 12-mm trocar (B) in the epigastric region, a 5-mm trocar (C) in the midclavicular line 1–2 cm below the costal margin, and another 5-mm trocar (D) in the right axillary line 4–5 cm below the costal margin.

FIG. 1.

Diagram of trocar position. LTCBDE was used with a 4-trocar technique; the first (10-mm) trocar (A) was placed below the umbilicus for insufflation of carbon dioxide and laparoscope access, a 12-mm trocar (B) was placed in the epigastric region, a 5-mm trocar (C) was placed in the midclavicular line 1–2 cm below the costal margin, and another 5-mm trocar (D) was placed in the right axillary line 4–5 cm below the costal margin. CBD, common bile duct; LTCBDE, laparoscopic transcystic CBD exploration.

After careful dissection and clearance of the triangle of Calot, the cystic artery was clipped and cut off in a standard manner. The cystic duct was dissected close to the gallbladder and clipped to prevent stone or bile migration. After further dissection and sufficient exposure of the cystic duct toward the CBD, a transverse incision of the cystic duct was performed (Fig. 2A). The bile duct anatomy was evaluated, and to facilitate the introduction of the choledochoscope, the cystic duct was dilated with a balloon catheter or occasionally with laparoscopic separation forceps. If the 5-mm flexible choledochoscope (Olympus, Tokyo, Japan) could not be inserted into the cystic duct or if the CBD stone was larger than the diameter of the cystic duct, a T-shaped incision was made 3–5 mm above the confluence of the cystic duct and the CBD (Fig. 2B).

FIG. 2.

(A) Transverse incision of the cystic duct. (B) T-shaped incision of the cystic duct and its confluence with the CBD. (C) Introduction of the choledochoscope through the cystic duct.

Next, the choledochoscope was introduced through the cystic duct to the CBD (Fig. 2C), and the CBD stones could be visualized directly (Fig. 3A). Normally, the CBD stones were retrieved individually by a wire basket, irrigation, or a combination of both through the cystic duct. If large or impacted CBD stones could not be extracted by these routine methods, a FREDDY laser fiber (U-100 system, World of Medicine, Berlin Germany) was installed from the working port of the choledochoscope and was used to break the CBD stones into pieces at an energy setting of 120 mJ per pulse and a repetition rate of 5 Hz (Fig. 3B). The tip of the FREDDY laser fiber is armed with a red aiming beam for accurate positioning on the surface of the CBD stones and reducing the risk of injuring the surrounding bile duct wall. The adequately fragmented stones were retrieved through the routine methods (Fig. 3C), and a final choledochoscopy check was performed to confirm complete clearance of the bile duct stone and absence of bile duct mucosal injury (Fig. 3D). After complete clearance of the CBD stones, the cystic duct was closed with clips or suture ligature (3–0 Vicryl). Next, the gallbladder was removed from the hepatic attachments through a standard procedure. Routinely, an abdominal drainage was placed in a subhepatic location. No T-tube or biliary stents were used after successful stone extraction. Patients were relocated to the general wards of the department of hepatopancreatobiliary surgery in a quiet and stable condition after the operation. Oral intake was prohibited during the first 24 hours postoperatively. Postoperative laboratory tests included a complete blood cell count and liver function tests.

FIG. 3.

(A) Common bile duct stone visualized with a choledochoscope. (B) Common bile duct stone under FREDDY laser lithotripsy. (C) Stone basket engagement after laser lithotripsy. (D) Postlithotripsy check with a choledochoscope demonstrating a patent common bile duct.

Follow-up

Patients were followed up in outpatient visits in the first and third months after release; next, patients were contacted by telephone every 3 months. Each individual patient was followed up for more than 6 months. General conditions, diet, operation-related discomfort, liver function, and radiology examinations were performed to screen for adverse events during follow-up.

Ethics statement

The ethics committee of the Second Affiliated Hospital of Nan Chang University approved this study and the use of clinical data. Informed consent was obtained from all of the patients.

Results

Patient characteristics are summarized in Table 1. Thirteen males and 19 females were recruited; the mean age in the present study was 54.9 years. Three patients (patients 7, 9, and 14) had a history of abdominal operations (Billroth-I gastrectomy, Billroth-II gastrectomy, and splenectomy, respectively). Preoperative liver function tests were obtained the day before the operation. The alanine aminotransferase (ALT) ranged from 9.62 to 306.9 (mean, 91.02) U/L; ALP ranged from 78.1 to 800.1 (mean, 236.35) U/L; GGT ranged from 10.9 to 1110.2 (mean, 331.29) U/L; and total bilirubin (Tbil) level ranged from 18.1 to 230.32 (mean, 79.81) μM. In terms of bile duct disease characteristics, the diameter of the CBD ranged from 10 to 20 (mean, 15.1) mm, and the number of CBD stones ranged from 1 to 5. CBD stones ranged in diameter from 9 to 18 (mean, 11.7) mm, and 9 patients had stones impacted in the CBD that could not be extracted by a wire basket, irrigation, or a combination of both methods.

Table 1.

Patient Characteristics

Patient	Sex/Age (years)	ASA class	ALT (U/L)	ALP (U/L)	GGT (U/L)	Tbil (μM)	Abdominal operative history	Diameter of largest CBD stone (mm)	Diameter of CBD (mm)	Impacted CBD stone	No.of CBD stones
1	F/60	II	22.86	133.1	280.7	56.55	—	11	15	No	2
2	M/59	II	32.28	86.4	112.1	32.28	—	12	15	No	4
3	F/60	II	15.5	110.8	23.4	45.2	—	12	15	No	3
4	F/43	I	19.16	78.1	15.6	34.54	—	11	13	No	1
5	F/81	III	73.05	238.9	245.8	69.95	—	16	18	No	3
6	M/75	III	157.56	399.3	495.5	83.07	—	12	16	No	2
7	F/57	II	94.5	120.6	331.2	184.14	Billroth-I gastrectomy	9	15	Yes	3
8	M/36	II	19.67	100.1	221.7	52.31	—	15	20	No	1
9	F/41	II	10.67	82.7	10.9	35.77	Billroth-II gastrectomy	18	20	No	3
10	M/66	II	106.76	477.8	504.5	59.56	—	16	20	No	1
11	F/62	II	9.62	101.7	107.9	31.85	—	11	12	Yes	3
12	F/79	III	129.95	353.8	327	103.6	—	10	16	No	3
13	F/62	II	29.07	89.1	22.3	73.24	—	14	20	No	2
14	M/40	II	172.54	187.4	387.6	86.07	Splenectomy	13	15	No	1
15	M/48	II	139.28	132.3	343.1	36.71	—	10	15	No	2
16	F/64	II	89.3	800.1	1110.2	200.3	—	10	12	Yes	1
17	M/55	II	256.42	255.8	570.4	68.79	—	9	10	No	1
18	F/60	II	119.75	375.1	329.8	143.19	—	10	14	Yes	2
19	F/26	II	306.9	140.2	172.9	105.15	—	9	13	Yes	1
20	F/38	I	11.48	114.9	130.8	18.1	—	12	13	No	2
21	F/68	III	47.8	228	162	27.3	—	10	18	No	1
22	F/76	III	40.73	418.5	640.8	98.42	—	10	18	No	3
23	M/58	II	22.17	290.4	524.1	147.09	—	17	20	Yes	2
24	M/40	II	24.17	136.8	156.6	25.66	—	10	12	No	1
25	F/18	II	220.25	291.1	535.4	95.71	—	12	15	No	1
26	M/60	II	64	224	142.5	31.43	—	12	13	No	5
27	M/53	II	114.95	139.8	671	36.87	—	10	14	No	3
28	M/38	II	179.42	223.7	321	62.14	—	10	11	No	2
29	M/67	III	33.32	181.7	89.2	48.36	—	9	12	No	3
30	F/56	I	214.17	192	422	157.18	—	10	12	Yes	3
31	F/71	III	63.8	657.6	626.1	73.07	—	10	15	Yes	1
32	F/41	II	71.72	201.3	567.2	230.32	—	14	16	Yes	1

F, female; M, male; ASA, American Society of Anesthesiologists; ALT, alanine aminotransferase; ALP, alkaline phosphatase; GGT, gamma-glutamyl transferase; Tbil, total bilirubin; CBD, common bile duct.

Operative outcome is shown in Table 2. The CBD stones were successfully cleared in all patients. The mean operative time was 123 minutes with a range of 72 to 155 minutes. Patient 7 had an impacted stone and abdominal history of Billroth-I gastrectomy and it is likely that these characteristics affected the operative time, which was the longest in this patient. The estimated blood loss during the operation ranged from 10 to 80 mL, and no intraoperative blood transfusion was needed. The mean length of the postoperative hospital stay was 5.3 (range, 4–7) days. All patients recovered normally with no perioperative morbidity or mortality. The mean follow-up duration was 8.5 (range, 6–15) months, and no bile duct injury, stricture, retained or recurrent stones, or other complications were observed during follow-up.

Table 2.

Operative Outcome

Patient	Technical success	Function of SOD	Operative time (min)	Estimated blood loss (mL)	Abdominal drainage (days)	Postoperative hospital stay (days)	Adverse event	Follow-up duration (months)
1	Yes	Normal	105	30	5	6	No	10
2	Yes	Normal	140	50	4	5	No	10
3	Yes	Normal	135	60	6	7	No	8
4	Yes	Normal	120	50	4	5	No	7.5
5	Yes	Normal	140	30	4	5	No	7.5
6	Yes	Normal	125	20	4	5	No	7
7	Yes	Normal	155	15	4	5	No	7.5
8	Yes	Normal	145	30	5	6	No	8.5
9	Yes	Normal	150	40	4	5	No	7
10	Yes	Normal	115	40	5	6	No	13
11	Yes	Normal	120	25	5	6	No	6
12	Yes	Normal	115	35	5	6	No	7.5
13	Yes	Normal	140	80	4	5	No	15
14	Yes	Normal	135	80	5	6	No	8
15	Yes	Normal	135	20	5	6	No	6.5
16	Yes	Normal	110	50	4	5	No	11
17	Yes	Normal	115	15	3	4	No	8.5
18	Yes	Normal	130	50	3	5	No	15
19	Yes	Normal	95	40	4	4	No	6.5
20	Yes	Normal	100	25	5	7	No	9.5
21	Yes	Normal	115	15	4	5	No	6
22	Yes	Normal	125	30	5	5	No	8
23	Yes	Normal	130	80	4	5	No	12.5
24	Yes	Normal	72	10	3	4	No	7.5
25	Yes	Normal	100	30	3	4	No	6
26	Yes	Normal	132	40	6	7	No	7.5
27	Yes	Normal	140	80	5	6	No	9.5
28	Yes	Normal	140	30	5	6	No	8
29	Yes	Normal	135	10	4	5	No	6
30	Yes	Normal	130	25	5	6	No	8
31	Yes	Normal	97	20	3	4	No	6.5
32	Yes	Normal	108	20	4	5	No	8

SOD, Sphincter of Oddi.

Discussion

LTCBDE is an effective technique and is the least invasive method for managing concomitant gallstones and CBD stones. The LTCBDE for CBD stone clearance has a high success rate, ranging from 85% to 95% in selected patients.¹² This technique has the advantage of protecting the integrity of the major bile duct from choledochotomy and preserving the function of the sphincter of Oddi. Furthermore, LTCBDE is associated with lower morbidity and a shorter hospital stay compared with laparoscopic choledochotomy CBD exploration.^4,12 However, the reported indication for LTCBDE is limited to stones that are smaller than the diameter of the cystic duct, a small number of stones, stones located in the CBD, and a favorable anatomy of the cystic duct-CBD junction.¹² For CBD stones larger than the cystic duct in diameter, the technique of a T-shaped incision in the cystic duct, 3–5 mm from its confluence with the CBD, can be helpful. This method has advantages, including easy access to and exploration of the CBD with a choledochoscope, straightforward retrieval of larger CBD stones, and no requirement for bile duct drainage. However, a T-shaped incision of the bile duct is not effective for impacted or larger CBD stones (more than 5 mm greater than the cystic duct diameter). In this setting, lithotripsy may be employed before stone extraction, including electrohydraulic lithotripsy (EHL) and laser lithotripsy.

EHL is an inexpensive technique used primarily for the fragmentation of difficult-to-remove CBD stones by endoscopy.¹⁹ However, complications occurred in up to 18% of cases: mostly recurrent jaundice, cholangitis, perforation, or bleeding.²⁰ Recently, laser lithotripsy has been used, and this technique is safer than EHL in general. The FREDDY laser and holmium laser are widely applied for fragmentation of bile duct stones.

The FREDDY laser system is a short-pulse, double-frequency solid-state laser with an 80% infrared component with a wavelength of 1064 nm and a 20% green component with a wavelength of 532 nm.²¹ The absorption of the green light causes the formation of a plasma bubble on the stone's surface that completely absorbs the simultaneously emitted infrared light. This combined action is synergistic, raising the intensity of the plasma and producing a more effective mechanical shockwave. Stone fragmentation relies on the generation of a plasma bubble with a final mechanical shockwave without any thermal effect compared with the holmium laser.²¹ The FREDDY laser system is safe and effective for the treatment of duct stones. In vitro experiments have demonstrated the application of FREDDY laser to lithotripsy, and animal model tests exhibited little or no effect on normal tissues.^22,23 One investigation of the effect of the FREDDY laser on the human urothelium reported only minimal edema after 300 pulses of 120 mJ each. In addition, 2000 pulses of the FREDDY laser failed to perforate human ureteric tissues ex vivo, while the holmium laser required, on average, only two pulses.²⁴

The FREDDY laser also has demonstrated advantages for treating bile duct stones in patients who could not be handled with a standard endoscopic approach or open surgery. The initial clinical use of the FREDDY laser for difficult CBD stones was reported by Hochberger et al. This study of 19 patients who underwent FREDDY laser lithotripsy with ERCP exhibited a successful bile duct clearance rate of 89%.¹⁴ Kim et al.¹⁵ reported a bile duct clearance rate of 15/17 (88%). These researchers used FREDDY laser lithotripsy with an ERCP balloon catheter under fluoroscopic guidance to fragment difficult CBD stones, which could not be extracted by a standard ERCP. In two patients, the impacted stones failed to fragment because the tortuous CBD and the biliary stricture caused inadequate positioning of the laser fiber. Liu et al.¹⁶ and Cho et al.¹⁷ used FREDDY laser lithotripsy through the transpapillary route, and the bile duct clearance rates were 90% and 92.3%, respectively. Jiang et al.¹⁸ reported FREDDY laser lithotripsy as an effective treatment option for large and impacted intrahepatic stones in open surgery with or without hepatectomy. The final stone clearance rate was 93.3%, and FREDDY laser lithotripsy was shorter in both operative time and hospital stay with a rate of complication no greater than the traditional method.¹⁸

To the best of our knowledge, this report presents the first clinical description of the clearance of CBD stones with combined LTCBDE and FREDDY laser lithotripsy. In this study, we further validate the usefulness and efficiency of the FREDDY laser system for large or impacted CBD stones. Compared with the aforementioned reports, we achieved 100% bile duct stone clearance for all 32 patients, and no complications occurred. Our patients with large or impacted CBD stones benefited from the modified LTCBDE and FREDDY laser lithotripsy in one operative setting with minimized exposure to anesthesia and shorter hospital stay. The most important point is that we gained access to the CBD with laparoscopy in a transcystic approach and avoided choledochotomy or sphincterotomy, thus freedom from T-tube- or ERCP-related complications.

Footnotes

Acknowledgment

The authors would like to thank the contributions of all of the patients in their retrospective study.

Disclosure Statement

No competing financial interests exist.

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