Surg Endosc (1992) 6:38-40
Surgical Endoscopy © Springer-VerlagNew York Inc. 1992
Peroral tunable-dye laser lithotripsy of intrahepatic stones in Oriental cholangitis Peter Goh, Yaman Tekant, and Eugene Sim Department of Surgery, National University Hospital, Lower Kent Ridge Road, Singapore 0511, Republic of Singapore
Summary. This case report details the use of a pulsed tunable-dye laser lithotripter in the endoscopic management of recurrent intrahepatic stones in a patient with Oriental cholangitis. A 42-year-old Chinese man had a cholecystectomy and choledochoduodenostomy in 1980. Subsequently he had three episodes of recurrent cholangitis which responded to medical treatment. The patient presented in April 1989 with a fourth attack of cholangitis. Endoscopic retrograde cholangiopancreatography (ERCP) and ultrasound demonstrated a large mass of stones in the right intrahepatic ductal system. A flexible upper gastrointestinal endoscope was passed into the right hepatic duct via the choledochoduodenostomy. The stones were fragmented with a tunable-dye laser and the residual fragments were removed endoscopically. Key words: Oriental cholangitis - Intrahepatic stones Tunable-dye laser - Laser lithotripsy
Although surgical bypass of the biliary tract is always a necessary step in the treatment of Oriental cholangitis, we feel that endoscopic access to the biliary tract should be maintained for recurrent stones in the intrahepatic ducts which often require endoscopic management. The therapeutic endoscopist has a wide variety of methods with which to deal with stones in the biliary tree, ranging from the use of simple forceps, balloons, and snares to lasers and ultrasonic and electrohydraulic lithotripters. The simpler devices often solve the problem when the stones are small in size and number. More sophisticated lithotriptic devices are necessary when dealing with large, multiple, or impacted stones associated with ductal strictures. The Candela flashlamp pumped tunable dye laOffprint requests to: Peter M.Y. Goh
sertripter (Candela Laser Corporation, 530 Boston Post Road, Wayland, MA 01778, USA) was approved by the Food and Drug Administration (FDA) in the USA for the treatment of biliary stones in June 1989. The case reported was treated in April 1989.
Case report A 42-year-old Chinese man was admitted on the 13th of April 1989 with a history of intermittent fever, chills, and rigors associated with right hypochondrial pain. The patient underwent a cholecystectomy in 1980 and a choledochoduodenostomy in 1984 for recurrent biliary stones. Since then he had had three further episodes of cholangitis which all responded to antibiotic therapy. In the most recent episode he was diagnosed on abdominal ultrasound as having multiple large calculi in the right intrahepatic duct. Endoscopic retrograde cholangiopancreatography (ERCP) under fluoroscopic control was performed twice, but conventional technique failed to remove the stones. He was transferred to the National University Hospital. Physical examination of the patient was unremarkable. There was no evidence of jaundice. His temperature was 36.8°C, pulse 80/ min, and blood pressure 120/80 mmHg. Appendectomy and cholecystectomy scars were present. The total bilirubin was normal (25/xmol/1), alkaline phosphatase raised to 252 IU/I (normal: 20-95 IU/1), and the white blood count was 11.12 units (normal: 4-11 units). The coagulation profile was normal. A cholangiogram was performed by passing an Olympus XQ 10 fiberscope into the choledochoduodenostomy opening and injecting dye into the biliary tree. This showed a large mass of stones occupying the dilated proximal right ductal system (Fig. 1). Endoscopic laser lithotripsy was performed in three sessions at 4-day intervals under sedation and antibiotic coverage by using an Olympus XQ10 flexible fiberoptic endoscope. Multiple stones in the right hepatic duct were directly visualized. A 200-/xm quartz fiber enclosed in a Teflon sheath was passed down the biopsy channel of the endoscope and placed in contact with the stones. The laser was used at 60 mW power with a 5- to 10-Hz pulse rate. The stones were fragmented into small, sandlike particles which could be flushed into the duodenum with a water jet. Larger fragments were removed with endoscopic forceps. Each treatment session took 1 hour. A postprocedure cholangiogram and computed tomography (CT) scan confirmed the ducts to be free of stones. Upper gastrointestinal endoscopy and choledochoscopy repeated 2 months later showed superficial duodenitis with no stones. There were no complications resulting from the procedure. Intrahepatic stones will invariably recur in the future as the primary pathology has not been eliminated.
39
Fig. 1. Endoscopic cholangiogram showing a flexible endoscope in the upper common hepatic duct injecting dye into the biliary tree. This shows a large mass of stones occupying and dilating the entire proximal right ductal system
Discussion
Laser lithotripsy is a new development in the management of retained intrahepatic stones. The flashlamp pulsed-dye laser was invented by researchers at International Business Machines (IBM) in 1966. A clinically commercial lithotripter was developed by W. Furomoto of Candela Laser in 1987 to fragment ureteric stones. This commercial tunable-dye laser was then tested on biliary stones at the Massachussetts General Hospital, Boston. The laser operated at the 504-nm wavelength to a maximum power of 60 mJ at a pulse rate of 1-20 Hz. The energy is delivered via a 200-/xm-diameter quartz fiber. The mechanism of stone fragmentation depends upon the formation of a ball of rapidly expanding plasma at the stone-fiber interface which causes microfractures in the stone which coalesce to form major cracks with stone fragmentation. This effect is augmented by a liquid medium which in addition results in the formation of a shock wave transmitted into the stone. Furthermore, the stone is prevented from recoiling backward away from the laser because of the impedance of the liquid medium. Hence the fragmentation is more efficacious in saline rather than in air. Pigment stones are more susceptible to ablation than cholesterol stones though both can be reliably fragmented [8]. Experimental studies on animals have shown that for energies less than 60 mJ per pulse, 58 pulses were required to perforate the bile duct when the fiber was in direct perpendicular contact with the bile duct wall [7].
Access to stones in the intrahepatic ducts may be percutaneous or peroral. Percutaneous approaches either via a T-tube or transhepatically are well described [3, 9, 10]. Perorally the stones can be accessed via a choledochoduodenostomy as in this case or with a mother-and-baby scope via a transampullary route [5]. The laser can also be introduced intraoperatively via a choledochotomy. The pulsed neodymium-yttrium aluminium garnet (Nd-YAG) laser has been used in the treatment of both common bile duct stones and intrahepatic stones. Various authors have reported a total number of 76 patients with intrahepatic and choledochal stones treated with the Nd-YAG laser. The stones were completely fragmented and removed in all except five of the cases (93%) [2, 4, 9, 10]. The main disadvantage of the pulsed Nd-YAG lithotripter is its propensity to produce a considerable amount of heat which may theoretically be damaging to the biliary ducts. Heat production is not a problem with the tunable-dye laser lithotripter. Kozarek (1988), in a case report, described the clinical use of a tunable-dye laser to fragment common bile duct stones [6]. Classen (1989) reported a series of 14 patients with ductal stones treated by Cotton in various centers in the United States with a success rate of 93% (13 of 14 patients) [1]. There appear to have been no reports of the use of this laser in the treatment of retained intrahepatic stones in Oriental cholangitis.
Conclusion
The tunable-dye laser is a device which allows one to fragment intrahepatic stones in any location in the liver where a fiber-optic or flexible videoendoscope can access. It is also gentle on tissue. Thus the margin of error as regards perforation of the biliary tree is limited. Laser lithotripsy of intrahepatic stones is an expensive and technically demanding option in the treatment of this disease. In the near future we do not foresee its widespread application, and it will most probably be available only in tertiary referral centers.
References 1. Classen M, Hagenmuller F (1989) Treatment of stones in the bile duct via duodenoscopy. Endoscopy 21:375-377 2. Ell C, Hochberger J, Muller D, Lux G, Demling L (1986) Erste erfolgreiche endoskopisch retrograde Laser-Lithotripsie am Menschen. Dtsch Med Wochenschr 111:1217 3. Jan Y (1984) Lithotomy of retained intrahepatic stones by laser. In: Pai-Ching Sheen, Chen-Guo Ker (eds) Gallstones and choledochoscope. Kaohsiung, Taiwan, Mei Yuh Co. Ltd pp 151-154 4. Kouzu T, Yamazaki Y, Ruy M, Isono K (1986) Cholangioscopic lithotomy using Nd:YAG laser. Dig Dis Sci 31(10 Suppl): 438S (Abst no: 1743) 5. Kozarek RA (1988) Direct cholangioscopy and pancreatoscopy at time of endoscopic retrograde cholangiopancreatography. Am J Gastroenterol 83:55-57 6. Kozarek RA, Low DE, Ball TJ: Tunable dye laser lithotripsy: invitro studies and invivo treatment of choledocholitiasis. Gastrointest Endosc 34:418-421
40 7. Nishioka NS, Kelsey PB, Kibbey A, Delmonico F, Parrish JA, Anderson RR (1988) Laser lithotripsy: animal studies of safety and efficacy. Lasers Surg Med 8:357-362 8. Nishioka NS, Levins PC, Murray SC, Parrish JA, Anderson RR (1987) Fragmentation of biliary calculi with tunable dye lasers. Gastroenterology 93:250-255
9. Orii K, Ozaki A, Takase Y, Iwasaki Y (1983) Lithotomy of intrahepatic and choledochal stones with Yag laser. Surg Gynecol Obstet 156:485-488 10. Orii K, Ozaki A, Takase Y, Sakita T, Iwasaki Y (1981) Choledocholithotomy by Yag laser with a choledocho-fiberscope: case of two patients. Surgery 90:120-122
Surgical Endoscopy © Springer-VerlagNew York Inc. 1992
Peroral tunable-dye laser lithotripsy of intrahepatic stones in Oriental cholangitis Peter Goh, Yaman Tekant, and Eugene Sim Department of Surgery, National University Hospital, Lower Kent Ridge Road, Singapore 0511, Republic of Singapore
Summary. This case report details the use of a pulsed tunable-dye laser lithotripter in the endoscopic management of recurrent intrahepatic stones in a patient with Oriental cholangitis. A 42-year-old Chinese man had a cholecystectomy and choledochoduodenostomy in 1980. Subsequently he had three episodes of recurrent cholangitis which responded to medical treatment. The patient presented in April 1989 with a fourth attack of cholangitis. Endoscopic retrograde cholangiopancreatography (ERCP) and ultrasound demonstrated a large mass of stones in the right intrahepatic ductal system. A flexible upper gastrointestinal endoscope was passed into the right hepatic duct via the choledochoduodenostomy. The stones were fragmented with a tunable-dye laser and the residual fragments were removed endoscopically. Key words: Oriental cholangitis - Intrahepatic stones Tunable-dye laser - Laser lithotripsy
Although surgical bypass of the biliary tract is always a necessary step in the treatment of Oriental cholangitis, we feel that endoscopic access to the biliary tract should be maintained for recurrent stones in the intrahepatic ducts which often require endoscopic management. The therapeutic endoscopist has a wide variety of methods with which to deal with stones in the biliary tree, ranging from the use of simple forceps, balloons, and snares to lasers and ultrasonic and electrohydraulic lithotripters. The simpler devices often solve the problem when the stones are small in size and number. More sophisticated lithotriptic devices are necessary when dealing with large, multiple, or impacted stones associated with ductal strictures. The Candela flashlamp pumped tunable dye laOffprint requests to: Peter M.Y. Goh
sertripter (Candela Laser Corporation, 530 Boston Post Road, Wayland, MA 01778, USA) was approved by the Food and Drug Administration (FDA) in the USA for the treatment of biliary stones in June 1989. The case reported was treated in April 1989.
Case report A 42-year-old Chinese man was admitted on the 13th of April 1989 with a history of intermittent fever, chills, and rigors associated with right hypochondrial pain. The patient underwent a cholecystectomy in 1980 and a choledochoduodenostomy in 1984 for recurrent biliary stones. Since then he had had three further episodes of cholangitis which all responded to antibiotic therapy. In the most recent episode he was diagnosed on abdominal ultrasound as having multiple large calculi in the right intrahepatic duct. Endoscopic retrograde cholangiopancreatography (ERCP) under fluoroscopic control was performed twice, but conventional technique failed to remove the stones. He was transferred to the National University Hospital. Physical examination of the patient was unremarkable. There was no evidence of jaundice. His temperature was 36.8°C, pulse 80/ min, and blood pressure 120/80 mmHg. Appendectomy and cholecystectomy scars were present. The total bilirubin was normal (25/xmol/1), alkaline phosphatase raised to 252 IU/I (normal: 20-95 IU/1), and the white blood count was 11.12 units (normal: 4-11 units). The coagulation profile was normal. A cholangiogram was performed by passing an Olympus XQ 10 fiberscope into the choledochoduodenostomy opening and injecting dye into the biliary tree. This showed a large mass of stones occupying the dilated proximal right ductal system (Fig. 1). Endoscopic laser lithotripsy was performed in three sessions at 4-day intervals under sedation and antibiotic coverage by using an Olympus XQ10 flexible fiberoptic endoscope. Multiple stones in the right hepatic duct were directly visualized. A 200-/xm quartz fiber enclosed in a Teflon sheath was passed down the biopsy channel of the endoscope and placed in contact with the stones. The laser was used at 60 mW power with a 5- to 10-Hz pulse rate. The stones were fragmented into small, sandlike particles which could be flushed into the duodenum with a water jet. Larger fragments were removed with endoscopic forceps. Each treatment session took 1 hour. A postprocedure cholangiogram and computed tomography (CT) scan confirmed the ducts to be free of stones. Upper gastrointestinal endoscopy and choledochoscopy repeated 2 months later showed superficial duodenitis with no stones. There were no complications resulting from the procedure. Intrahepatic stones will invariably recur in the future as the primary pathology has not been eliminated.
39
Fig. 1. Endoscopic cholangiogram showing a flexible endoscope in the upper common hepatic duct injecting dye into the biliary tree. This shows a large mass of stones occupying and dilating the entire proximal right ductal system
Discussion
Laser lithotripsy is a new development in the management of retained intrahepatic stones. The flashlamp pulsed-dye laser was invented by researchers at International Business Machines (IBM) in 1966. A clinically commercial lithotripter was developed by W. Furomoto of Candela Laser in 1987 to fragment ureteric stones. This commercial tunable-dye laser was then tested on biliary stones at the Massachussetts General Hospital, Boston. The laser operated at the 504-nm wavelength to a maximum power of 60 mJ at a pulse rate of 1-20 Hz. The energy is delivered via a 200-/xm-diameter quartz fiber. The mechanism of stone fragmentation depends upon the formation of a ball of rapidly expanding plasma at the stone-fiber interface which causes microfractures in the stone which coalesce to form major cracks with stone fragmentation. This effect is augmented by a liquid medium which in addition results in the formation of a shock wave transmitted into the stone. Furthermore, the stone is prevented from recoiling backward away from the laser because of the impedance of the liquid medium. Hence the fragmentation is more efficacious in saline rather than in air. Pigment stones are more susceptible to ablation than cholesterol stones though both can be reliably fragmented [8]. Experimental studies on animals have shown that for energies less than 60 mJ per pulse, 58 pulses were required to perforate the bile duct when the fiber was in direct perpendicular contact with the bile duct wall [7].
Access to stones in the intrahepatic ducts may be percutaneous or peroral. Percutaneous approaches either via a T-tube or transhepatically are well described [3, 9, 10]. Perorally the stones can be accessed via a choledochoduodenostomy as in this case or with a mother-and-baby scope via a transampullary route [5]. The laser can also be introduced intraoperatively via a choledochotomy. The pulsed neodymium-yttrium aluminium garnet (Nd-YAG) laser has been used in the treatment of both common bile duct stones and intrahepatic stones. Various authors have reported a total number of 76 patients with intrahepatic and choledochal stones treated with the Nd-YAG laser. The stones were completely fragmented and removed in all except five of the cases (93%) [2, 4, 9, 10]. The main disadvantage of the pulsed Nd-YAG lithotripter is its propensity to produce a considerable amount of heat which may theoretically be damaging to the biliary ducts. Heat production is not a problem with the tunable-dye laser lithotripter. Kozarek (1988), in a case report, described the clinical use of a tunable-dye laser to fragment common bile duct stones [6]. Classen (1989) reported a series of 14 patients with ductal stones treated by Cotton in various centers in the United States with a success rate of 93% (13 of 14 patients) [1]. There appear to have been no reports of the use of this laser in the treatment of retained intrahepatic stones in Oriental cholangitis.
Conclusion
The tunable-dye laser is a device which allows one to fragment intrahepatic stones in any location in the liver where a fiber-optic or flexible videoendoscope can access. It is also gentle on tissue. Thus the margin of error as regards perforation of the biliary tree is limited. Laser lithotripsy of intrahepatic stones is an expensive and technically demanding option in the treatment of this disease. In the near future we do not foresee its widespread application, and it will most probably be available only in tertiary referral centers.
References 1. Classen M, Hagenmuller F (1989) Treatment of stones in the bile duct via duodenoscopy. Endoscopy 21:375-377 2. Ell C, Hochberger J, Muller D, Lux G, Demling L (1986) Erste erfolgreiche endoskopisch retrograde Laser-Lithotripsie am Menschen. Dtsch Med Wochenschr 111:1217 3. Jan Y (1984) Lithotomy of retained intrahepatic stones by laser. In: Pai-Ching Sheen, Chen-Guo Ker (eds) Gallstones and choledochoscope. Kaohsiung, Taiwan, Mei Yuh Co. Ltd pp 151-154 4. Kouzu T, Yamazaki Y, Ruy M, Isono K (1986) Cholangioscopic lithotomy using Nd:YAG laser. Dig Dis Sci 31(10 Suppl): 438S (Abst no: 1743) 5. Kozarek RA (1988) Direct cholangioscopy and pancreatoscopy at time of endoscopic retrograde cholangiopancreatography. Am J Gastroenterol 83:55-57 6. Kozarek RA, Low DE, Ball TJ: Tunable dye laser lithotripsy: invitro studies and invivo treatment of choledocholitiasis. Gastrointest Endosc 34:418-421
40 7. Nishioka NS, Kelsey PB, Kibbey A, Delmonico F, Parrish JA, Anderson RR (1988) Laser lithotripsy: animal studies of safety and efficacy. Lasers Surg Med 8:357-362 8. Nishioka NS, Levins PC, Murray SC, Parrish JA, Anderson RR (1987) Fragmentation of biliary calculi with tunable dye lasers. Gastroenterology 93:250-255
9. Orii K, Ozaki A, Takase Y, Iwasaki Y (1983) Lithotomy of intrahepatic and choledochal stones with Yag laser. Surg Gynecol Obstet 156:485-488 10. Orii K, Ozaki A, Takase Y, Sakita T, Iwasaki Y (1981) Choledocholithotomy by Yag laser with a choledocho-fiberscope: case of two patients. Surgery 90:120-122
