Management of Benign Biliary Strictures

Introduction

Management of benign biliary strictures (whether surgical, percutaneous-transhepatic, or by endoscopic means) is difficult.1–4 These lesions are formed of cicatricial fibrosis and are recalcitrant to many minimally invasive techniques.^1–3 They can be a contributing factor to recurrent cholangitis, hepatic segmental atrophy, hepatic graft dysfunction (in cases of transplanted livers), and in the long-run, obstructive biliary cirrhosis.^2–4

Benign biliary strictures are a heterogenous group of lesions that differ in demographics (patient types), locations within the biliary tract, etiology, and disease process (pathology). Firstly, there are pediatric transplant recipients, adult transplant recipients, and adult non-transplant patients with native livers. Pediatric transplant recipients have smaller ducts than adults (transplanted or native livers), and transplant recipients (pediatric or adults) have transplanted livers that have a relatively compromised arterial supply compared to most patients with native livers (see Outcomes for relevance). Secondly, they vary in morphology and location (Fig. 135-1). Thirdly, they vary in etiology and pathogenesis, including inflammatory processes, infectious processes, inflammatory-ischemic processes, thermal injuries from laparoscopic complications, surgical-technical complications at surgical anastomoses (scarring), and (less commonly) radiation injury.^1,5–11 Many key studies amalgamate disease processes, and/or transplant versus non-transplants, and/or stricture locations (peripheral vs. anastomotic), and/or types of anastomoses (duct-to-duct vs. biliary-enteric anastomoses (see Fig. 135-1).^4,12–13 As a result, it is difficult to discuss anatomic and functional (clinical) outcomes specific to a uniform population or a particular pathologic-anatomic biliary stricture.

FIGURE 135-1 Flow chart demonstrating classification of benign biliary strictures based on transplant vs. native livers and based on lesion location. Another dimension of variation not included in flow chart is etiology of benign stricture. Non-anastomotic extrahepatic lesions are in common hepatic duct. Hilar intrahepatic lesions are lesions at confluence of main right and main left biliary ducts or in main right or left biliary ducts. Only exception is if a surgical anastomosis is right at the confluence (almost no biliary stump). In this case, we would consider it anastomotic (extrahepatic).

The types and locations of benign biliary strictures that are encountered vary depending on the referral pattern and expertise of the institution. However, overall, the vast majority of benign biliary strictures are either (1) peripheral intrahepatic (the ones that are solitary and treatable), commonly related to liver transplantation, and/or (2) anastomotic biliary strictures (whether in transplanted or native livers). For the purpose of this chapter (with its limited scope), these two lesions will be discussed. Non-anastomotic central (hilar or common hepatic bile duct) lesions are treated similarly to anastomotic benign biliary strictures, and they will be discussed as one entity.

Indications

Peripheral Intrahepatic Benign Biliary Strictures

The limited indications for managing peripheral intrahepatic benign biliary strictures are confined to cholangitis with or without biliary stones. The primary issue when contemplating the management of peripheral intrahepatic benign biliary strictures is to make sure this is not a diffuse hepatobiliary process that will develop multiple lesions. Diffuse hepatobiliary processes include primary sclerosing cholangitis and diffuse hepatic graft ischemia. Percutaneous transhepatic biliary management of multiple lesions is futile and probably requires several transhepatic biliary drains. The risks versus benefit of managing multiple lesions tilts heavily toward the risks. Furthermore, treat the patient and not the lesion. If the patient is asymptomatic and has no cholangitis, leave the biliary stricture alone, which will probably cause segmental atrophy of the hepatic segment being drained by the constricted biliary duct segment, with compensatory hypertrophy of adjacent hepatic segments. The only exception is an undersized hepatic graft (usually a pediatric recipient) with involvement of a relatively large hepatic segment. In this case, the involved hepatic segment may not be dispensable.

Central Benign Biliary Strictures (Anastomotic and Nonanastomotic)

Indications include cholangitis with or without biliary stones, biliary stones, cholestasis with pruritus, abnormal liver function tests with concern for developing biliary cirrhosis, and hepatic graft dysfunction. The most definitive treatment of central strictures is a hepaticojejunostomy.4,14–16 However, redo hepaticojejunostomies have a lower clinical success rate.^4,17 Difficult hepaticojejunostomy candidates (candidates for percutaneous or endoscopic management) include poor surgical candidates owing to comorbidities, patients refusing surgery, numerous adhesions and inflammatory process in the porta hepatis, and short biliary stumps in patients with preexisting hepaticojejunostomies.⁴

Contraindications

Peripheral Intrahepatic Benign Biliary Strictures

Non-candidacy includes asymptomatic patients and/or patients with diffuse hepatobiliary processes with multiple lesions (see earlier). General contraindications include active sepsis, uncorrected coagulopathy, hemobilia, and possibly ascites. Ascites may have a higher risk for bleeding and may cause leakage of ascitic fluid around the internal-external percutaneous transhepatic biliary drain (PTBD) (high morbidity). However, it is not an absolute contraindication in the author’s opinion.

Central Benign Biliary Strictures (Anastomotic and Non-anastomotic)

General contraindications include active sepsis, uncorrected coagulopathy, hemobilia, and possibly ascites (see earlier). In addition, an active biliary leak from the surgical anastomosis is a contraindication to transhepatic balloon dilation, which may increase the leak or rupture the surgical anastomosis.

Equipment

Peripheral Intrahepatic Benign Biliary Strictures

This includes standard internal-external as well as external PTBDs to establish and maintain percutaneous transhepatic access to the biliary tract. Small-caliber, high-pressure (>12 atm), noncompliant balloons are used. The balloon is sized 100% to 110% of the target biliary duct and probably does not exceed 5 to 6 mm.2,13 Remember that right or left main bile duct (hilar) strictures are included in central benign biliary strictures (see later).

Central Benign Biliary Strictures (Anastomotic and Non-anastomotic)

This includes standard internal-external as well as external PTBDs to establish and maintain percutaneous transhepatic access to the biliary tract. High-pressure (>12 atm) noncompliant balloons are used. The balloon is sized 100% to 125% of the target biliary duct and usually ranges from 6 to 15 mm (Table 135-1).^2–3,13,18 Pediatric and adult split-graft transplant recipients usually require smaller balloons (6-10 mm) compared to whole grafts or native livers (7-15 mm).²

TABLE-135-1

Technical Features and Results of Four Transhepatic Balloon Dilation Protocols for Percutaneous Management of Benign Biliary Strictures

Study and Year		Zajko, 1995¹³	Saad, 2005¹⁸	Saad, 2006³	Cantwell, 2008⁴
Sample Size		N = 56	N = 38	N = 22	N = 85
Balloon Features	Type	Conventional	Conventional	Conv + cutting	Conventional
	Max pressure (atm)	10-12	>12-15	>12-15	N/M
	Max diameters (mm) (mean)	7-15 (N/M)	6-14 (8.0)	7-12 (9.1)	8-12 (N/M)
	Cumulative duration of inflation per session (min)	20-30	1-5	10-20	3-15
Regimen/Treatment*	Dilation session per treatment (mean)	1-6 (3.0)	1-3 (1.2)	1-3 (1.8)	1-4 (1.4)
	Balloon inflations per session	2-3	1	2-3	3-5
	Duration of regimen (weeks)	1-2	0-12	0-4.3	0-12^†
Technical Results	Overall technical success (%)	<89%^‡	85	93	100
Technical Results	Major traumatic complications (%)	<5.6%^‡	3.8	0.0	2.0

atm, Atmosphere; Conv, conventional; Max, maximum; min, minutes; mm, millimeters; (N/M), not mentioned.

^*Terminology may differ.

^†Estimate.

^‡Overall technical success rate and complication rates by Zajko et al. amalgamated intrahepatic peripheral lesion dilation and extrahepatic anastomotic dilations.

Modified from Saad WEA. Percutaneous management of postoperative anastomotic biliary strictures. Tech Vasc Interv Radiol 2008;11:143–53.

Unconventional balloons that have been used include the cutting balloon (Boston Scientific, Natick, Mass.). This is a noncompliant balloon with four microsurgical blades (atherotomes) mounted longitudinally along the outer surface of the balloon. The atherotomes are 1.5 to 2.0 centimeters in length and are 0.127 in depth for all balloon sizes.³ The cutting balloon comes in diameters from 5 to 8 mm and requires use of a coaxial 0.018-inch wire. The 7- and 8-mm diameters require a 7F introducer sheath.³ A drawback is that available diameters of this balloon are limited; 40% of lesions have been found to require balloon sizes greater than 8 mm, which are not available for cutting balloons.³ The PolarCath (for cryoplasty) from Boston Scientific has been mentioned as a potential tool for managing benign biliary strictures,^2–3 but to the best of our knowledge, its use has not been published.

Covered stents (stent-grafts) can also be used.¹⁹ There are two commercially available stent-grafts that can be placed percutaneously or endoscopically but are mostly removed by endoscopic means. However, they can be removed transhepatically, but not by design. These two stents-grafts are the VIABIL (W.L. Gore & Associates, Flagstaff, Ariz.) and the WallFlex (Boston Scientific).