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Pseudocalculus of the common bile duct
Pseudocalculus of the Common Bile Duct A Dynamic Radiographic Differentiation
from True Retained Stone
Mark Wertheimer, MD, Salt Lake City, Utah Wallace S. Brooke, MD, PhD, Salt Lake City, Utah P. Ruben Koehler, MD, Salt Lake City, Utah James A. Nelson, MD, Salt Lake City, Utah
Exploration of the common bile duct is performed approximately 125,000 times each year in the United States. The incidence of retained overlooked calculi in these patients approaches 4 per cent or 5,000 per year [I]. The dangers of retained calculi and the hazards of repeated common duct surgery are widely appreciated. This dilemma has stimulated considerable interest in the prevention of retained calculi with more widespread use of intraoperative cholangiographic and endoscopic technics. Nonoperative removal of retained calculi in the immediate postoperative period by instrumentation of the common duct through T-tube tracts has been increasingly applied with some noteworthy success [2]. In the past four years we have seen five patients with static T-tube cholangiographic evidence of retained distal common duct calculi. A dynamic preoperative cholangiogram demonstrated these to artifacts of common bile duct be “pseudocalculi,” physiology and anatomy, not true calculi. The relative unfamiliarity with this phenomenon, described previously by Beneventano and Schein [3], prompted this report to prevent occasional unwarranted surgical reexploration or duct instrumentation.
From the Departments of Surgery and Radiology, University of Utah Medical Center, and Department of Surgery, Holy Cross Hospital, Salt Lake City, Utah. Reprint requests shoukl be addressed to Wallace S. Brooke. MD, Medical Tower Building, 1060 East First So., Salt Lake City, Utah 84102 Presented at the Twenty-Seventh Annual Meeting of the Southwestern Surgical Congress, Las Vegas, Nevada, April 21-24, 1975.
742
Illustrative Material Figures 1 and 2 each demonstrate a clear example of the “pseudocalculus” sign in the left hand frame of the composite pictures. Note the abrupt cessation of dye, the convexity simulating a meniscus and apparent evidence of a retained calculi within the duct. The right hand frames in these two composites each demonstrate another static cholangiogram taken at another point in time during the study. The unobstructed patent duct is appreciated in these views. Figure 3 demonstrates, in clockwise rotation, four separate frames from a dynamic, fluoroscopically controlled cholangiogram on a single patient. It is easy to recognize, in this series of x-ray films, the significant distance from the duodenal wall at which the sphincteric spasm occurs. That the spasm is involved within the distal common duct and not the sphincter of Oddi within the duodenal lumen or wall is easily appreciated. The eventual patency of the common duct is readily apparent. Comments The unique anatomy and physiology of the distal common duct, the so-called ampulla of Vater, are responsible for the production‘of the “pseudocalculus” sign. Boyden [4] has demonstrated an anatomically distinct, submucosal, smooth muscled sphincter surrounding the distal 5 to 6 mm of the common bile duct as it en&s the duodenal wall. This mechanism is separate from the sphincter of Oddi and has a separate embryologic origin from the duodenal musculature. It is anchored to the duodenal wall by auxiliary muscle fibers. The apparent function of this sphincter is to regulate
The American Journal of Surgery
Pseudocalculus of Common Bile Duct
Figure 1. Static cholanglogram. A, clear example of the “pseudocalculus” sign; 6, at another interval during the study, note the unobstructed patent duct.
Figure 2. Static cholangiogram. A, clear example of the “pseudocahw Ills” sign; 6, at another interval during the study, note the unobstructed patent duct.
bile flow between the gallbladder, common duct, and duodenum. Contraction of the sphincter forces flow of bile into the gallbladder while relaxation allows flow into the duodenum. These functions are mediated by the hormone cholecystokinin, which causes relaxation of the sphincter as well as gallbladder contraction. Beneventano and Schein _ 131 _ have demonstrated a normal biphasic, systolic, and diastolic activity in the Vaterian segment of the common duct using
Volume 130. December 1975
cinecholangiographic methods. During the socalled systolic phase, the sphincter is contracted and bile is prevented from entering the duodenum. These cyclic changes are independent of duodenal peristalsis. During maximal sphincter contraction, contrast material in the common bile duct may demonstrate a convexity or a meniscus identical to that which might be produced by a true calculus. sign. The timeThis is the “pseudocalculus” chance factor may produce a “pseudocalculus”
743
Wertheimer
et al
Figure 3. A dynamic, fluoroscopkally controlled chofanghqram in one patient.
sign if only isolated static cholangiograms are taken, even in normal common bile ducts. It has also been shown that too forceful injection of contrast material may prolong the systolic phase and increase the potential for obtaining a “pseudocalculus” sign. When isolated static films do suggest a retained calculus, a dynamic, fluoroscopic cholangiogram may demonstrate the normal cyclic systolic and diastolic activity of the distal common bile duct and the truly patent channel free of calculus obstruction. The risk of mortality with reexploration of the common bile duct for retained calculi has been reported as high as 25 per cent in even the most experienced hands [5]. The true incidence of morbidity related to common duct sphincter damage, after repeat exploration, is not known. It may be legitimately expected to be significantly high. The nonoperative extirpation of retained common bile duct calculi, by means of T-tube tract instrumentation, has been reported to be associated with a 5 per cent incidence of cholangitis [2]. Unfortunately, many of these patients suspected of having retained common bile duct calculi are aged, poor risk patients with a high incidence of associated cardiac, pulmonary, and cerebrovascular disease who
744
are least able to tolerate reoperation or the complications of bile duct instrumentation. Recognizing these dangers and the anatomic and physiologic basis for the “pseudocalculus” sign, we advocate consultation with our colleagues in radiology in order that some form of dynamic radiographic assessment precede any planned reexploration or instrumentation of the common bile duct. Summary
Static T-tube cholangiographic evidence of distal common duct calculi may in fact be only “pseudocalculi,” which might be elucidated by a dynamic fluoroscopic study. We have seen five such cases. X-ray evidence for this phenomenon is presented. Pertinent anatomy, physiology, and clinical considerations are discussed. References 1. Glenn F: Retained calculi within the biliiry ductal system. Ann Surg 179: 528. 1974. 2. Mazzarriello R: Review of 220 cases of residual biliiry tract calculi treated without reoperatiin: an eight year study. Surgery, 73: 299, 1973. 3. Beneventano TC. Schein CJ: The physiologic basis of cholangiographic interpretation: pseudocalculus sign and problem
The American Journal of Surgery
Pseudocalculus
of duct spasm. Surgery 63: 673, 1968. 4. Boyden EA: The anatomy of the choledochoduodenal junction in man. Surg GynecolObstet 104: 641, 1957. 5. Way LW, Admirand WH, Dunphy JE: Management of choledocholiihiasis. Ann Surg 176: 347. 1972.
Discussion Wallace S. Brooke: Since the sphincter of Boyden is separate from the papilla and duodenal wall and is thick, sphincteroplasty should extend at least 6 to 7 mm. Morphine, Innovaf, and other drugs used in anesthesia may cause spasm, whereas glucagon, nitrates, and secretin may reverse this. This presentation illustrates that surgeons should know how T-tube cholangiograms are done in their own hospital x-ray departments, that is, at what pressure and whether fluoroscopy is used. Lawrence W. Way (San Francisco, CA): Some stones that are retained after previous surgery actually pass in the postoperative period, so the surgeon presented with a suggestive x-ray film has these two possibilities before he should contemplate any active attempt to eliminate
Volume 130, December 1975
of Common
Bile Duct
the stone. In support of the passage concept, it has been shown by Nyhus and others some years ago that stones put into experimental animals usually do pass. Cole reported a series of patients in whom stones that were rather obvious passed spontaneously. Because of the effects of the surgical instrumentation, because of the hazards of possibly reexciting cholangitis, and because of the factors that were presented herein, we recommend that when the postoperative cholangiogram taken a week or ten days after surgery suggests the presence of a stone, when the fluoroscopist is not able to rule out a stone by suspecting and proving pseudocalculus, that nothing at all he done for this patient for another three or four weeks to let all the inflammation subside as much as possible. During that period of time, if the pseudocalculus sign had actually been present, this most likely will be detected on the next cholangiogram and the radiologist definitely must have this entity in mind. If the presence of a stone is proved after this waiting interval, then something more active such as manipulation of the duct can be performed with safety and with the lowest risk of producing cholangitis.
from True Retained Stone
Mark Wertheimer, MD, Salt Lake City, Utah Wallace S. Brooke, MD, PhD, Salt Lake City, Utah P. Ruben Koehler, MD, Salt Lake City, Utah James A. Nelson, MD, Salt Lake City, Utah
Exploration of the common bile duct is performed approximately 125,000 times each year in the United States. The incidence of retained overlooked calculi in these patients approaches 4 per cent or 5,000 per year [I]. The dangers of retained calculi and the hazards of repeated common duct surgery are widely appreciated. This dilemma has stimulated considerable interest in the prevention of retained calculi with more widespread use of intraoperative cholangiographic and endoscopic technics. Nonoperative removal of retained calculi in the immediate postoperative period by instrumentation of the common duct through T-tube tracts has been increasingly applied with some noteworthy success [2]. In the past four years we have seen five patients with static T-tube cholangiographic evidence of retained distal common duct calculi. A dynamic preoperative cholangiogram demonstrated these to artifacts of common bile duct be “pseudocalculi,” physiology and anatomy, not true calculi. The relative unfamiliarity with this phenomenon, described previously by Beneventano and Schein [3], prompted this report to prevent occasional unwarranted surgical reexploration or duct instrumentation.
From the Departments of Surgery and Radiology, University of Utah Medical Center, and Department of Surgery, Holy Cross Hospital, Salt Lake City, Utah. Reprint requests shoukl be addressed to Wallace S. Brooke. MD, Medical Tower Building, 1060 East First So., Salt Lake City, Utah 84102 Presented at the Twenty-Seventh Annual Meeting of the Southwestern Surgical Congress, Las Vegas, Nevada, April 21-24, 1975.
742
Illustrative Material Figures 1 and 2 each demonstrate a clear example of the “pseudocalculus” sign in the left hand frame of the composite pictures. Note the abrupt cessation of dye, the convexity simulating a meniscus and apparent evidence of a retained calculi within the duct. The right hand frames in these two composites each demonstrate another static cholangiogram taken at another point in time during the study. The unobstructed patent duct is appreciated in these views. Figure 3 demonstrates, in clockwise rotation, four separate frames from a dynamic, fluoroscopically controlled cholangiogram on a single patient. It is easy to recognize, in this series of x-ray films, the significant distance from the duodenal wall at which the sphincteric spasm occurs. That the spasm is involved within the distal common duct and not the sphincter of Oddi within the duodenal lumen or wall is easily appreciated. The eventual patency of the common duct is readily apparent. Comments The unique anatomy and physiology of the distal common duct, the so-called ampulla of Vater, are responsible for the production‘of the “pseudocalculus” sign. Boyden [4] has demonstrated an anatomically distinct, submucosal, smooth muscled sphincter surrounding the distal 5 to 6 mm of the common bile duct as it en&s the duodenal wall. This mechanism is separate from the sphincter of Oddi and has a separate embryologic origin from the duodenal musculature. It is anchored to the duodenal wall by auxiliary muscle fibers. The apparent function of this sphincter is to regulate
The American Journal of Surgery
Pseudocalculus of Common Bile Duct
Figure 1. Static cholanglogram. A, clear example of the “pseudocalculus” sign; 6, at another interval during the study, note the unobstructed patent duct.
Figure 2. Static cholangiogram. A, clear example of the “pseudocahw Ills” sign; 6, at another interval during the study, note the unobstructed patent duct.
bile flow between the gallbladder, common duct, and duodenum. Contraction of the sphincter forces flow of bile into the gallbladder while relaxation allows flow into the duodenum. These functions are mediated by the hormone cholecystokinin, which causes relaxation of the sphincter as well as gallbladder contraction. Beneventano and Schein _ 131 _ have demonstrated a normal biphasic, systolic, and diastolic activity in the Vaterian segment of the common duct using
Volume 130. December 1975
cinecholangiographic methods. During the socalled systolic phase, the sphincter is contracted and bile is prevented from entering the duodenum. These cyclic changes are independent of duodenal peristalsis. During maximal sphincter contraction, contrast material in the common bile duct may demonstrate a convexity or a meniscus identical to that which might be produced by a true calculus. sign. The timeThis is the “pseudocalculus” chance factor may produce a “pseudocalculus”
743
Wertheimer
et al
Figure 3. A dynamic, fluoroscopkally controlled chofanghqram in one patient.
sign if only isolated static cholangiograms are taken, even in normal common bile ducts. It has also been shown that too forceful injection of contrast material may prolong the systolic phase and increase the potential for obtaining a “pseudocalculus” sign. When isolated static films do suggest a retained calculus, a dynamic, fluoroscopic cholangiogram may demonstrate the normal cyclic systolic and diastolic activity of the distal common bile duct and the truly patent channel free of calculus obstruction. The risk of mortality with reexploration of the common bile duct for retained calculi has been reported as high as 25 per cent in even the most experienced hands [5]. The true incidence of morbidity related to common duct sphincter damage, after repeat exploration, is not known. It may be legitimately expected to be significantly high. The nonoperative extirpation of retained common bile duct calculi, by means of T-tube tract instrumentation, has been reported to be associated with a 5 per cent incidence of cholangitis [2]. Unfortunately, many of these patients suspected of having retained common bile duct calculi are aged, poor risk patients with a high incidence of associated cardiac, pulmonary, and cerebrovascular disease who
744
are least able to tolerate reoperation or the complications of bile duct instrumentation. Recognizing these dangers and the anatomic and physiologic basis for the “pseudocalculus” sign, we advocate consultation with our colleagues in radiology in order that some form of dynamic radiographic assessment precede any planned reexploration or instrumentation of the common bile duct. Summary
Static T-tube cholangiographic evidence of distal common duct calculi may in fact be only “pseudocalculi,” which might be elucidated by a dynamic fluoroscopic study. We have seen five such cases. X-ray evidence for this phenomenon is presented. Pertinent anatomy, physiology, and clinical considerations are discussed. References 1. Glenn F: Retained calculi within the biliiry ductal system. Ann Surg 179: 528. 1974. 2. Mazzarriello R: Review of 220 cases of residual biliiry tract calculi treated without reoperatiin: an eight year study. Surgery, 73: 299, 1973. 3. Beneventano TC. Schein CJ: The physiologic basis of cholangiographic interpretation: pseudocalculus sign and problem
The American Journal of Surgery
Pseudocalculus
of duct spasm. Surgery 63: 673, 1968. 4. Boyden EA: The anatomy of the choledochoduodenal junction in man. Surg GynecolObstet 104: 641, 1957. 5. Way LW, Admirand WH, Dunphy JE: Management of choledocholiihiasis. Ann Surg 176: 347. 1972.
Discussion Wallace S. Brooke: Since the sphincter of Boyden is separate from the papilla and duodenal wall and is thick, sphincteroplasty should extend at least 6 to 7 mm. Morphine, Innovaf, and other drugs used in anesthesia may cause spasm, whereas glucagon, nitrates, and secretin may reverse this. This presentation illustrates that surgeons should know how T-tube cholangiograms are done in their own hospital x-ray departments, that is, at what pressure and whether fluoroscopy is used. Lawrence W. Way (San Francisco, CA): Some stones that are retained after previous surgery actually pass in the postoperative period, so the surgeon presented with a suggestive x-ray film has these two possibilities before he should contemplate any active attempt to eliminate
Volume 130, December 1975
of Common
Bile Duct
the stone. In support of the passage concept, it has been shown by Nyhus and others some years ago that stones put into experimental animals usually do pass. Cole reported a series of patients in whom stones that were rather obvious passed spontaneously. Because of the effects of the surgical instrumentation, because of the hazards of possibly reexciting cholangitis, and because of the factors that were presented herein, we recommend that when the postoperative cholangiogram taken a week or ten days after surgery suggests the presence of a stone, when the fluoroscopist is not able to rule out a stone by suspecting and proving pseudocalculus, that nothing at all he done for this patient for another three or four weeks to let all the inflammation subside as much as possible. During that period of time, if the pseudocalculus sign had actually been present, this most likely will be detected on the next cholangiogram and the radiologist definitely must have this entity in mind. If the presence of a stone is proved after this waiting interval, then something more active such as manipulation of the duct can be performed with safety and with the lowest risk of producing cholangitis.