Occlusion Of Cystic Duct Research Articles

A New Method for Thermocholecystectomy

The authors tested the feasibility of thermocholecystectomy for gallbladder ablation in an animal model. Thermal treatment of the cystic duct followed by heating of the saline-filled gallbladder using a separately designed heater/expander was performed in 13 pigs (group I). In four animals, heating of the gallbladder alone was performed (group II). Two animals served as controls (group III). All animals were killed 12 weeks after treatment. There was cystic duct occlusion in 10 (77%) of 13 of group I animals. In 6 (60%) of 10 of these animals with cystic duct occlusion, there was complete ablation of the gallbladder mucosa and complete obliteration of the gallbladder lumen. In group II animals, all cystic ducts were intact with an unchanged gallbladder volume in all four animals (100%), and normal gallbladder mucosa were intact in three (75%) of four animals. The gallbladders and cystic ducts in group III animals were normal. This study demonstrates many technical difficulties with thermal cholecystectomy. However, under ideal conditions, permanent gallbladder ablation is feasible in our animal model using a specially designed heating system.

Percutaneous obliteration of the cystic duct with a holmium:yttrium-aluminum-garnet laser: results of in vitro and animal experiments.

The purpose of this study was to investigate the feasibility of using a holmium:yttrium-aluminum-garnet laser to permanently occlude the cystic duct in order to isolate the gallbladder from the biliary-enteric circulation and prevent gallstone formation. To determine the optimal laser parameters (power and pulsing rate) for cystic duct thermocoagulation, 20 freshly excised porcine gallbladders with intact cystic ducts underwent low-energy (0.075-0.085 J/pulse) or high-energy (0.20-0.25 J/pulse) thermocoagulation. Histopathologic examination was done to determine the extent of cystic duct injury. After in vitro experiments, percutaneous transcholecystic laser thermocoagulation of the cystic duct was performed on 23 anesthetized domestic pigs (four controls). Cholangiograms immediately after laser thermocoagulation were obtained to assess cystic duct occlusion. Animals were sacrificed for histopathologic correlation immediately after laser thermocoagulation (n = 4), 72 hr later (n = 4), and 6 weeks later (n = 15). In the in vitro studies, all 10 cystic ducts in the high-energy group were occluded, while only four in the low-energy group were occluded. At histology, all cases in both groups showed circumferential injury to the cystic duct wall without injury to the cystic artery or vein. In the in vitro experiments, the cystic duct was successfully cannulated in 21 (91%) of 23 animals. Cholangiography after thermocoagulation showed occlusion of the cystic duct in 16 (84%) of 19 cases. Immediately after laser thermocoagulation, the cystic duct mucosa was circumferentially destroyed, whereas after 72 hr necrosis of the cystic duct wall and periductal tissues had occurred. By 6 weeks, all pigs had complete cystic duct fibrosis without injury to the common bile duct. Holmium:yttrium-aluminum-garnet laser thermocoagulation of the cystic duct can be performed easily, results in immediate cystic duct occlusion, and leads to permanent fibrous ductal obliteration by 6 weeks.

The value of sonography in determining cystic duct patency

A prospective blinded comparison of ultrasonography (US) and oral cholecystography (OCG) was performed in 100 patients with symptomatic gall-stones to determine whether US would enable an accurate assessment of cystic duct patency to be made. Patency of the cystic duct was defined as gall-bladder opacification on OCG or a greater than 20% decrease in gall-bladder volume by US post-fatty meal. The ellipsoid method of volume measurement was used. Any patient who had a non-opacified gall-bladder on OCG but a greater than 20% volume decrease on US had cholescintigraphy performed (DISIDA). Oral cholecystography demonstrated cystic duct patency in 88 patients (88%), and fatty-meal gall-bladder US met the specified study criteria for patency in 86 patients (86%). False negative results were identified in four of the OCG and in six of the US examinations. The results of this study indicate that gall-bladder sonography with a post-fatty meal contraction of greater than 20% is a very accurate predictor of cystic duct patency. A contraction of less than 20%, however, cannot be considered a reliable predictor of cystic duct occlusion.

Sclerotherapy of the Gallbladder in Pigs

Gallbladder sclerotherapy after permanent cystic duct occlusion, to prevent gallstone recurrence in nonsurgical gallstone therapy, is at least a two-stage procedure. A balloon catheter was developed to perform gallbladder sclerotherapy with only temporary occlusion of the cystic duct, and the efficacy and safety of this method was subsequently investigated. Twenty pigs underwent cholecystostomy for positioning of a 7-Fr triple-lumen balloon catheter with proximal side holes. Sclerotherapy with 96% ethanol and 3% sodium tetradecyl sulfate for 20 minutes was performed. The animals were killed 24 hours, two, six, and 12 weeks after the procedure. The balloon catheter functioned well and seems suitable for procedures in which a temporary occlusion of the cystic duct is required. Although gallbladders after six and 12 weeks were shrunken and fibrotic, a single treatment of gallbladder sclerotherapy with subsequent catheter removal and no permanent cystic duct occlusion, as performed in this experiment, did not produce complete gallbladder ablation. In this study, sclerotherapy proved safe in the short term, but long-term effects remain to be assessed.

Interventional Radiologic Alternatives to Cholecystectomy

It has been estimated that 20 million people in the United States have gallstone disease. The choice of the optimal management strategy for a patient with symptomatic gallstones in the 1990s will take into account the clinical status of the patient, the characteristics of the gallstones, and the patient's preference. Only patients whose doctors understand the advantages and disadvantages of the newer methods can make properly informed choices. When interventional radiologic alternatives to cholecystectomy are being contemplated, one approach is to first consider the patient's clinical presentation (acute or nonacute) and then their risk of death after cholecystectomy (low or high). Figure 5 shows an algorithmic approach to the management of gallbladder stones based on this concept. This algorithm also can be used as a framework for discussion of treatment options with any individual patient.

Radiologic Ablation of the Gallbladder: An Alternative to Cholecystectomy in the Twenty–First Century

Twenty pigs underwent (a) cystic duct occlusion by means of fluoroscopically guided transcatheter endoluminal bipolar radio–frequency (RF) electrocoagulation and (b) gallbladder sclerotherapy with one of two different regimens of ethanol and sodium tetradecylsulfate (STS). Serum ethanol levels and hepatic enzyme tests showed no acute toxicity. Postmortem histologic studies showed that the bile ducts beyond the occlusion site remained entirely unaffected in all animals. In three of four animals followed up for 2 weeks, the sclerosants induced necrosis of the gallbladder mucosa, but the adjacent liver, serosa, and blood vessels remained intact. In 13 of 16 animals followed up for 8 weeks, the gallbladder lumen was obliterated by fibrous scar tissue. In the animals treated with 95% ethanol and 3% STS, the gallbladder mucosa was necrotic in all areas after 2 weeks (two of two animals) and eradicated completely after 8 weeks (six of eight animals); the other regimen (70% ethanol plus 1% STS) was somewhat less effective. In this study, the combination of RF–mediated cystic duct occlusion and gallbladder sclerotherapy with ethanol and STS permitted gallbladder ablation in swine without toxic side effects.

Catheter for endoluminal bipolar electrocoagulation.

An interventional catheter was designed that can induce controlled endoluminal tissue lesions by means of bipolar radio-frequency (RF) electrocoagulation under fluoroscopic guidance. The technique was used to obtain safe and reproducible percutaneous occlusion of the porcine cystic duct by reactive endoluminal scar formation. The new triple-lumen, 7-F, polyethylene catheter contains two insulated active wires and accommodates a 0.038-inch steerable guide wire, which facilitates insertion and placement of the active catheter tip under fluoroscopic control. The coagulation technique is relatively simple and requires only a small, portable bipolar RF generator and ammeter.

Effect of cholecystectomy on common bile duct diameters: a longitudinal prospective ultrasonographic study.

The medium-term effect of cholecystectomy on common bile duct diameters (CBD) was investigated prospectively in 64 patients with gallstone disease examined by ultrasonography immediately before and 27 months to 39 months after the operation. In 32 patients with chronic cholecystitis and patent cystic ducts, CBD diameters increased slightly (median 4.6 mm pre- and 5.3 mm postoperatively; p less than 0.05). A group of 19 patients with acute cholecystitis or cystic duct occlusion showed a significant decrease (median 7.7 mm pre- and 5.5 mm postoperatively; p less than 0.05). In 13 patients with common bile duct stones, the CBD diameters also decreased significantly after surgical intervention (median 7.5 mm pre- and 5.0 mm postoperatively; p less than 0.05). The widest CBD diameter after cholecystectomy observed in this study was 10 mm. We conclude that either increases or decreases of the CBD diameters may occur after cholecystectomy in patients with calculous gallbladder disease, and that the postoperative evolution is governed by the exact nature of the underlying biliary disease at the time of the index operation.

Long-term occlusion of the porcine cystic duct by means of endoluminal radio-frequency electrocoagulation.

Recurrent cholelithiasis must be expected after gallstone removal without cholecystectomy. Chemical gallbladder ablation may offer prevention but requires preliminary cystic duct occlusion. Radio-frequency (RF) electrocoagulation of the cystic duct was performed in 15 pigs to induce occlusion by a controlled thermal epithelial injury. A flexible coagulation catheter was placed into the cystic duct lumen under fluoroscopic control by means of either subhepatic cholecystostomy or direct, percutaneous transhepatic gallbladder puncture. Complete cystic duct occlusion was proved in 14 animals. Follow-up ranged from 1 to 17 weeks (mean, 11 weeks). Histologically, the RF technique induced an intense chronic inflammatory and fibroblastic reaction, which eventually obliterated the coagulated cystic duct segments. There was no epithelial regeneration or recanalization of the fibrotic cystic duct segments. The adjacent structures, particularly the cystic artery, were intact in all specimens.

Cystic duct occlusion and transcatheter sclerosis of the gallbladder in the rabbit.

We have identified a reliable sclerosant of the gallbladder in rabbits. After ligating the cystic ducts with a silk ligature in 24 rabbits and aspirating the bile from the gallbladder, we instilled a mixture of 95% ethanol and either 2 M% trifluoroacetic acid (TFA) or 5 M% TFA into the gallbladder. The animals were killed after 6 or 8 weeks. Ethanol with TFA resulted in replacement of gallbladder lumen with fibrous tissue in 22 rabbits. The two sclerosants were equally reliable and produced quantitatively similar fibrosis in the rabbits. The tendency for normal biliary mucosa to repopulate a sclerosed gallbladder can be obviated by complete occlusion of the cystic duct. The parameters for successful transcatheter sclerosis of the gallbladder have now been defined in an animal model.

Acute and Chronic Cholecystitis

The combination of chemical irritants and cystic duct occlusion by either gallstones, mucus, or inflammation, appears to be responsible for the development of acute and chronic cholecystitis in most cases. Once the diagnosis of acute cholecystitis is established, early cholecystectomy is usually recommended. An emergency operation should be performed if there is evidence of deterioration. In uncomplicated acute cholecystitis, the operation is urgent. In chronic cholecystitis, the operation can be scheduled at the convenience of the patient, but only after the concurrent diseases have been treated and the patient’s condition stabilized.

Roles of lithogenic bile and cystic duct occlusion in the pathogenesis of acute cholecystitis

The hypothesis that the elements essential for the induction of acute cholecystitis are the presence of lithogenic bile and cystic duct occlusion was tested in the prairie dog gallstone model. Neither the presence of gallstones alone nor acute cystic duct occlusion alone resulted in acute inflammation of the gallbladder. Acute cholecystitis developed in prairie dog gallbladders containing cholesterol-saturated bile, with or without gallstones, shortly after cystic duct occlusion. These data suggest that the factors essential for the induction of acute cholecystitis are the presence of lithogenic bile and cystic duct occlusion and that gallstones, although frequently present, are not an essential prerequisite to acute inflammation.

Reassessment of Simple Cholecystostomy

Cholecystostomy was performed on 22 patients with acute cholecystitis after partial (13) or complete (9) removal of gallbladder stones. One patient had complementary common-duct drainage. Early mortality occurred in two patients. Three patients with associated cholangitis but intraoperative reflux of cysticduct bile were all treated by cholecystostomy alone and survived. For the poor-risk patient with cholecystitis, cholecystostomy is effective. When there is associated cholangitis and documented cystic-duct patency, cholecystostomy is also sufficient. When accompanying cholangitis is associated with cystic-duct occlusion, choledochotomy and T tube drainage should be added.

On the Changes of Bile Constituents in Cases of Cystic Duct Occlusion by an Impacted Calculus

On the Changes of Bile Constituents in Cases of Cystic Duct Occlusion by an Impacted Calculus

Width of the common bile duct in cases of cystic duct occlusion by an impacted calculus.

Width of the common bile duct in cases of cystic duct occlusion by an impacted calculus.