Long-Term Results of Hepatic Resection for Hepatolithiasis

Long-term results of hepatic resection for hepatolithiasis in 34 patients having intrahepatic biliary strictures were studied. The left lateral and the right posterior segmental ducts were commonly and often simultaneously involved. Fourteen patients had multiple segmental involvement. Hepatic resection included left sided resection (n=27), right sided resection (n=6), and repeated bilateral resection (n=1). Seven patients had biliary tumors: 3 cholangiocarcinomas, 2 gall bladder cancers, cystadenocarcinoma, and dysplasia of intrahepatic ducts. Nineteen patients received bilioenteric anastomosis. Retained stones and recurrent stones developed in 3 and 4 patients, respectively. Twenty-six patients had no remaining symptoms; 2 died of operative complication or cholangiocarcinoma; 6 presented symptoms caused by retained stones (n=2), recurrent stones (n=2), bile stasis (n=1), or neuralgia (n=1). In 4 of the 6 patients, unrelieved posterior duct strictures caused the symptoms. With a mean follow-up period of 4.5 years, 30 patients are symptoms free, and 27 are stone free. In patients with right lobar or bilobar type, intra- and extrahepatic type, and confluence strictures, bilioenteric anastomosis is required. Hepatic resection is a rational treatment for hepatolithiasis, however, meticulous management of biliary tract abnormalities, particularly the posterior duct stricture, is mandatory.


INTRODUCTION
The main goal oftreatment for hepatolithiasis consists of complete removal of stones and elimination of bile stasis. The presence of intrahepatic biliary stricturesrepresents a clinical problem as to the management of this disease. Among various treatment modalities4-s, hepatic resection can offer a chance ofcure for patients with primary hepatolithiasis by eradicating stones, strictures, and diseased hepatic parenchyma. However, for complicated patients, appropriate procedures for biliary tract abnormalities together with hepatic resection are needed for successful treatment. This article summarizes our results of hepatic resection in the past 10 years in 34 patients with hepatolithiasis. We stress the importance of thorough retrieval and proper management of intrahepatic biliary abnormalities.

PATIENTS AND METHODS
Between January 1985 and August 1994, 34 patients (13 men and 21 women) with hepatolithiasis having intrahepatic biliary stricture underwent elective hepatic resections. The patients' age ranged from 37 to 84 years with a mean of 60 years. All patients had varying degrees of cholangitis. Six patients presented with acute pancreatitis; 2 presented with a liver abscess. Seven patients had biliary tumors, including 3 cholangiocarcinomas, 2 gall bladder cancers, hepatic cystadenocarcinoma, and dysplasia ofthe intrahepatic ducts. Nineteen patients had undergone more than one previous biliary operation as follows: cholecystectomy (n=19), choledochotomy (n=l 1), choledochojejunostomy 37 38 M. SATO et al.
Before surgery, patients underwent a full radiological examination including sonography, computed tomography, endoscopic retrograde cholangiography, and/or percutaneous transhepatic cholangiography. All patients underwent cholangioscopy and/or cholangiography both during and after surgery. Stones were removed endoscopically using an electrohydraulic lithotriptor or a basket catheter. Referring to the Japanese classification of hepatolithiasis9, patients were classified as follows." bilobar type (type LR) in 9 patients, left lobar type (type L) in 19, and right lobar type (type R) in 6; intrahepatic type (type 1) in 14 patients and both intra-and extrahepatic type (type IE) in 20. Intrahepatic bile ducts were defined according to Healey' anatomy ofthe intrahepatic ducts 1 and abbreviated as follows: the hepatic duct (HD), the left lateral segmental duct (LD), the left median segmental duct (MS), the right anterior segmental duct (AS), and the right posterior segmental duct (PS).
The indication for hepatic resection was when unextractable stones behind marked intrahepatic biliary strictures or marked hepatic atrophy were present. In cases having bilateral involvement, we resected the more damaged side of the liver, usually the left side. One-stage bilateral hepatic resection was avoided. Left lateral segmentectomy is the most common procedure among various types of hepatic resection (Table 1). One patient who received left lateral segmentectomy also underwent right posterior segmentectomy because ofretained stones in the posterior ducts. In patients with bilobar involvement, dilated bile duct, or extrahepatic involvement, Roux-en-Y bilioenteric anastomoses were constructed for postoperative choledocoscopy (POC). As for the levels of bilioeneteric anastomoses, we used the common hepatic duct (hepatico-jejuno-stomy:HJ) in cases without remaining strictures, or bilateral hepatic ducts (hilar hepaticojejunostomy: hHJ) in cases with bilateral involvement, confluence strictures, or unrelieved strictures in the contralateral lobe.
In hilar HJ, bilateral hepatic ducts were opened by a longitudinal incision beyond the strictures of the confluence up to the point where we could see the orifices ofindividual segmental ducts. Endoscopic management included postoperative biliary dilation in 2 patients, lithotomy in 14 patients (before surgery: 1, during surgery: 9, and after surgery: 6), and strictomy in one patient.
The precise locations of stones and strictures in individual intrahepatic ducts were determined by cholangiograms. The mean follow-up period was 4.5 years ranging from 0.5 to 9.5 years. The results of surgery were assessed in August 1994 and classified according to symptoms related to cholangitis after surgery as follows: good when they experienced no symptoms, fair when they had episodes of mild cholangitis which subsides at present, and poor when they are receiving special treatment for further cholangitis.

RESULTS
Thirty-one patients had brown pigment stones, while the other 3 had cholesterol stones. Packed stones and segmental atrophy of the liver were found in 31 and 25 patients, respectively. Anomalies of biliary tracts included anomalous joining posterior ducts to the left hepatic duct in 4 patients, left-sided gall bladder in 1, and Situs inversus in 1. A total of 58 segmental ducts had stones, 36 of which were packed stones ( Table 2). In 14 cases (41%), stones were located in two or more segments, including LS + PS in 7 cases, LS+MS in 3, AS+PS in 2, LS+MS+PS in 1, and all segments in 1. LS and PS were involved commonly and simultaneously.  (Table 3). Figure shows cholangiograms of a patient with multiple retained stones behind the unrelieved stricture ofthe right posterior duct which were detected by POC. The causes of retained stones after surgery included overlooking stones (n=5), remaining unresected part ofthe segment VII (n= 1), insufficient stone removal by intraoperative choledochoscopy (n= 1), and the presence of gall bladder cancer (n= 1). Five patients who underwent complete stone clearance after surgery did not develop recurrent stones.
One patient who received left lateral segmentectomy for impacted stones behind the stricture in this segment had unrelieved mild stricture ofthe posterior duct which was not accompanied by stones (Table 3). She subsequently developed progressive stricture ofboth the posterior duct and the anterior duct. She presented cholangitis even without residual stones. She needed transhepatic insertion of an internal bypass catheter between the posterior duct and the left hepatic duct to minimize the bile stasis. She had an anomalous joining posterior duct to the left hepatic duct.
Recurrent stones were detected in 4 patients 3 to 7 years after hepatic resection (Table 3). Only one patient received biliary reconstruction at the time of hepatic resection. Three patients underwent complete stone clearance by either HJ or endoscopic sphincterotomy. Thereafter, one ofthe 3 patients developed anastomotic stenosis of the HJ and recurrent stones. This patient received percutaneous transhepatic choledochoscopic lithotomy and drainage, but she will need further surgery. Excluding 3 patients (2 patients who died of surgery or recurrent cholangioma and one patient who suffers from liver cirrhosis associated with hepatitis C virus), the present conditions of 31 patients were good in 25 patients, fair in 4, and poor in 2. Six patients presented remaining symptoms after surgery due to retained stones (n=2), recurrent stones (n=2), bile stasis (n= 1), and neuralgia (n= 1). In 4 of the 6 patients, posterior duct stricture caused the symptoms. At present, 27 surviving patients are stone free; 30 patients are symptoms free.

DISCUSSION
Since the affected part ofthe liver is gradually destroyed and replaced by fibrous tissue due to repeated cholangitis in hepatolithiasis, the segmental atrophy is a good candidate for hepatic resection,3,7. High occurrence ofcholangiocarcinoma in atrophic segments as in our series is another reason which justifies hepatic resection for this disease. As to the extent ofhepatic resection, the resection line should be wide enough to remove the diseased part completely. Incomplete hepatic removal is more likely to occur in right sided hepatic   This study clarifies the features of intrahepatic biliary tract abnormalities. The.result is better in left unilateral type patients than right or bilobar type patients.
We should pay attention to the left median segment in case of left sided hepatic resection, since stones in the median segment are difficult to diagnose preoper-.atively. In cases having fibrosis in the median segment, or confluence stricture, left hepatic lobectomy is advocated rather than lateral segrnentectomy to avoid re-  tained stones in this segment. Meticulous retrieval and suitable management of the posterior segmental duct are key points for successful treatment. First, the posterior duct is the second most commonly affected duct, often simultaneously with the left lateral segmental duct. Second, stones and strictures in the posterior duct are likely to be overlooked by preoperative radiological investigations or even by intraoperative choledochoscopy. In our series, all retained stones following left sided hepatic resection remained in the posterior ducts. POC was successful only when there was no residual stricture of this duct. Third, the anomalous drainage pattern 11 and the sharp angulations ofthe posterior duct leads to the failure ofcholedocoscopy during surgery.
Only 3 patients had residual stones at discharge, but the other 5 had retained stones after surgery. Nonopacification of the affected ducts caused by biliary obstruction due to packed stones or strictures was the main cause ofretained stones in most cases. All segmental ducts, particularly the posterior duct, should be demonstrated definitely with cholangioscopy and cholangiography using fluoroscopy during surgery and operative sonography. After surgery, we should perform POC in all cases to detect missed stones. Patients with bilobar involvement, both extra-and intrahepatic involvement, and multiple biliary strictures are likely to develop retained stones after surgery. Patients having right lobar involvement, or receiving no biliary bypass are at high risk of recurrent stones. For these cases, bilioenteric anastomoses should be constructed as access routes for POC. In cases with bilateral involvement, multiple strictures, or confluence strictures, we advocate hilar HJ rather than HJ, because it relieves confluence strictures and provides direct visualization of all segmental ducts, and wide stomas. We believe that the hepatic hilum, including bilateral hepatic ducts and all orifices or segmental ducts, should be left unresected to avoid late anastomotic stenosis even in cases undergoing hemihepatectomy.
In conclusion, our resultsjustify hepatic resection for hepatolithiasis with intrahepatic biliary strictures. Me-ticulous retrieval ofnon-opacified ducts is important to delineate all stones and strictures. Proper management of biliary tract abnormalities, particularly posterior duct stricture, is essential for successful treatment. In cases having posterior duct stricture, through management such as long-term dilatation1,6,8, or staged bilateral hepatic resection is required to eliminate the pathophysiology.