Correlating motor performance with surgical error in laparoscopic cholecystectomy

BACKGROUND

Analysis of motor performance in minimally invasive surgery (MIS) is a new field with applications in surgical training, surgical simulators, and robotics. Force/torque and derivatives of tool tip position (velocity, acceleration, and jerk) are examples of measures of motor performance (MMPs). Few studies have measured MMPs or have correlated MMPs with surgical performance during MIS on humans. The objectives of this study were to determine the feasibility of a novel multimodal system to quantify MMPs in laparoscopic cholecystectomy and to attempt to correlate MMPs with the magnitude of error as a measure of surgical performance.

METHODS

Novice and expert surgeons performed laparoscopic cholecystectomies in two groups of three patients each. MMPs were obtained using a combination of optical and electromagnetic tool tip tracking and a force/torque sensor on a modified Maryland dissector. Error scores for laparoscopic cholecystectomy were calculated using a previously validated system. Novice and expert measurements were compared, and correlations were made between error scores and MMPs.

RESULTS

Error scores were similar between novices and experts. Novice surgeons had a significantly greater mean velocity (566 +/- 83 vs 85 +/- 32 mm/s, p = 0.006) and acceleration (2,600 +/- 760 vs 440 +/- 174 mm/s2, p = 0.050) compared to expert surgeons. Force (16.5 +/- 4.6 vs 18.3 +/- 6.0 N, p = 0.829), position (121 +/- 25 vs 135 +/- 72 mm, p = 0.863), and jerk (19,600 +/- 7,410 vs 2,430 +/- 367 mm/s3, p = 0.138) were similar between groups. A positive correlation was found in novice surgeons between error score and jerk (Pearson correlation, 0.999; p = 0.035).

CONCLUSIONS

It is feasible to quantify MMPs in laparoscopic cholecystectomy. Novice and expert surgeons can be differentiated by MMPs; moreover, there may be a positive correlation between jerk and error score in novice surgeons.

Automated high-frequency posture sampling for ergonomic assessment of laparoscopic surgery

BACKGROUND

Despite widespread acknowledgement that strain injuries do occur to surgeons, ergonomic assessments in minimally invasive surgery are comparatively rare. Current assessment techniques rely on labor-intensive manual recording techniques, so there is a need for an automated system.

METHODS

We used an optoelectronic measurement system to make postural measurements at frequencies of ~5 Hz and then converted these measurements to ergonomic stress scores using a modified Rapid Upper Limb Assessment (RULA) method.

RESULTS

We successfully recorded postures at least once per second during 96% of the time the surgeon was performing tissue manipulation tasks. We found that the ergonomic stress scores were comparatively high throughout the procedure, particularly for the wrist.

CONCLUSION

An automated high-frequency postural measurement system is feasible for making ergonomic assessments in an intraoperative setting. Such a system will also be a critical component in validating surgical simulations for use in training and credentialing surgeons and in designing and evaluating equipment.

Major intrahepatic bile duct injuries detected after laparotomy: selective nonoperative management

BACKGROUND

Abdominal trauma causing major intrahepatic bile duct injury is a relatively uncommon occurrence. Most authorities recommend operative, usually resectional, management of these injuries when recognized, citing increased risks of complications and mortality with nonoperative management. However, very few data have been published to document the optimal management of these challenging injuries.

METHODS

We present a series of five patients with significant hepatic injury and documented major bile duct injury managed at a single provincial trauma center. All of these patients had first- or second-order bile duct injuries diagnosed using endoscopic retrograde cholangiopancreatography and had developed complications caused by the ductal injury.

RESULTS

In all patients, the bile duct injury and resulting complication were successfully managed by a combination of endoscopic drainage procedures and interventional radiology techniques. Average length of hospital stay for these patients was 45 days. All patients eventually attained preinjury functional status.

CONCLUSION

Nonoperative techniques can be used to successfully manage selected patients and represent a reasonable alternative to operative intervention and resectional therapy, especially in the compromised patient. Extended length of stay is to be expected, but good outcomes can be achieved.

Hierarchical decomposition of laparoscopic procedures

The purpose of this report is to outline the hierarchical decomposition of surgical procedures, from surgical steps through tasks and subtasks to tool motions, and highlight implications for surgical training systems. Three common laparoscopic procedures were analysed: cholecystectomy, inguinal hernia repair, and Nissen fundoplication. In laparoscopic training workshops and operating rooms, our observational research included split screen videotaping of both the endoscopic view and our video camera's view of the primary surgeon. Videotapes were extensively annotated and analysed to yield timelines of each procedure, with component surgical steps, substeps, tasks, and subtasks duration as a function of procedure. The hierarchical decomposition of surgical procedures provides a framework for structuring a systematic approach to training, in the real and simulated environment. An example comparing variations in the fundoplication procedure is presented. Our results also have important implications for the design and assessment of new technology and intelligent tools in endoscopic surgery.

The effects of physical constraints in laparoscopic surgery

In order to provide guidelines for the development and evaluation of advanced laparoscopic instrumentation (including teleoperated devices), we assessed the impact of constrained motion on surgeons' ability to perform standardized pick-and-place and suturing tasks when using an emulation of a perfectly transparent teleoperator under direct, binocular vision. The surgeons' performance when using the emulator represents an upper bound on performance using any conceivable teleoperator with one-to-one force and motion scaling. Our analysis examines the mean differences in task completion time between three open tool configurations and two laparoscopic tool configurations with various degrees of freedom (DOFs). Fifteen laparoscopic surgeons participated in the study. We show that avoiding reversed hand and tool motions and adding DOFs significantly improves suturing performance. In the pick-and-place task, avoiding the reversed motions also improves performance, but adding DOFs to an open tool configuration does not. For both tasks, subjects who use open tools constrained to four DOF complete their tasks in approximately 38% less time than when using standard four-DOF laparoscopic tools. The marginal benefit to overall surgical time of adding two additional degrees of freedom is likely to be small (approximately 2%), although surgeons may then feel confident in attempting more difficult procedures.

Inverted Meckel's diverticulum: an entity simulating an ileal polyp

A case of inverted Meckel's diverticulum is described. This presented as an ileal polyp in an individual with chronic unexplained iron deficiency anemia. Most prolapsed Meckel's diverticula occur acutely as intussusceptions with bowel obstruction and characteristically develop in childhood. This case therefore represents an unusual surgical problem in an older individual in which the diagnosis was clinically unexpected.

Radiofrequency ablation of porcine liver in vivo: effects of blood flow and treatment time on lesion size

OBJECTIVE

To determine, in vivo, the effect of radiofrequency ablation (RFA) treatment time and tissue blood flow on the size and shape of the resulting necrotic lesion in porcine liver.

SUMMARY BACKGROUND DATA

Radiofrequency ablation is an electrosurgical technique that uses a high frequency alternating current to heat tissues to the point of desiccation (thermal coagulation). Radiofrequency ablation is well established as the treatment of choice for many symptomatic cardiac arrhythmias because of its ability to create localized necrotic lesions in the cardiac conducting system. Until recently, a major limitation of RFA was the small lesion size created by this technique. Development of bipolar and multiple-electrode RFA probes has enabled the creation of larger lesions and therefore has expanded the potential clinical applications of RFA, which includes the treatment of liver tumors. A basic understanding of factors that influence RFA lesion size in vivo is critical to the success of this treatment modality. The optimal RFA technique, which maximizes liver lesion size, has yet to be determined. Theoretically, lesion size varies directly with time of application of the RF current, and inversely with blood flow, but these relationships have not been previously studied in the liver.

METHODS

Six animals underwent hepatic RFA (460 kHz), for 5, 7.5, 10, 12.5, 15, and 20 minutes. Identical, predetermined anatomic areas of the liver were ablated in each animal. Two additional animals underwent 12 RFA treatments -- 6 with vascular inflow occlusion (Pringle maneuver) and 6 with uninterrupted hepatic blood flow. Animals were euthanized and the livers were removed for gross pathologic examination. All lesions were measured in three dimensions and photographed. Tissues were examined by routine histology and by histochemistry to determine viability.

RESULTS

Increasing duration of RFA application from 5 through 20 minutes did not create lesions of larger diameter, but this time increase did predict deeper lesion production (beta = 0.34, p = 0.04). A range of lesion shapes were created from four separate ovals (corresponding to each electrode), to larger ovals intersecting to form a cross, to spheroid lesions. The number of blood vessels in close proximity to the probe tip (within a 1-cm radius from the center of the lesion) strongly predicted minimum lesion diameter (beta = -0.61, p = 0.0001) and lesion volume (beta = -0.56, p = 0.0004). This negative effect of blood flow on lesion size was confirmed experimentally. Radiofrequency ablation lesions created during a Pringle maneuver were significantly larger in all three dimensions than lesions created without a Pringle maneuver: minimum diameter was 3.0 cm (with Pringle) versus 1.2 cm (p = 0.002), maximum diameter was 4.5 cm (with Pringle) versus 3.1 cm (p = 0.002), depth was 4.8 cm (with Pringle) versus 3.1 cm (p < 0.001), and lesion volume was 35.0 cm3 (with Pringle) versus 6.5 cm3 (p < 0.001).

CONCLUSIONS

Blood flow is a strong predictor of all RFA lesion dimensions in porcine liver in vivo, whereas a change of treatment time from 5 to 20 minutes is predictive only of lesion depth, but not diameter or volume.

Blunt bowel and mesenteric injury: diagnostic performance of CT signs

PURPOSE

Our goal was to determine the sensitivity and specificity of various CT signs of blunt bowel and mesenteric injury.

METHOD

The CT findings of 31 patients with blunt abdominal trauma were retrospectively assessed by three observers in consensus. All patients had laparotomy within 24 h of CT. The study group consisted of 19 patients with surgically proven bowel and/or mesenteric injury. The control group consisted of 12 traumatized patients who had no bowel or mesenteric injury. The CT signs assessed were presence, location, and extent of intraperitoneal fluid, extraluminal air, bowel wall thickening, bowel wall discontinuity, mesenteric streaking, and mesenteric hematoma.

RESULTS

In the 12 cases of bowel injury (9 transmural injury, 3 partial thickness injury), the CT sign of bowel wall thickening had sensitivity of 50% and specificity of 84% and the CT sign of bowel wall discontinuity had sensitivity of 58% and specificity of 95%. Extraluminal air was a specific but relatively insensitive sign of transmural bowel injury (sensitivity 44%, specificity 100%). In the 13 patients with mesenteric injuries, the CT sign of mesenteric hematoma had sensitivity of 54% and specificity of 94%. Isolated mesenteric streaking was a less specific sign of mesenteric injury (sensitivity 77%, specificity 44%). The finding of peritoneal fluid with no visible solid organ injury was a useful sign of bowel or mesenteric injury, occurring in 11 of 19 (58%) study patients and none of the controls (p < 0.001).

CONCLUSION

Bowel wall thickening, bowel wall discontinuity, extraluminal air, and mesenteric hematoma are reasonably specific CT signs of bowel and mesenteric injury following blunt abdominal trauma. The presence of a moderate to large volume of intraperitoneal fluid without visible solid organ injury is an important sign of bowel or mesenteric injury.

Don't cry over spilled stones? Complications of gallstones spilled during laparoscopic cholecystectomy: case report and literature review

The gallbladder is perforated and stones are spilled more frequently during laparoscopic cholecystectomy than during open cholecystectomy. Recent reports have implicated spilled gallstones as a source of infrequent but serious complications of laparoscopic of laparoscopic cholecystectomy. They can cause serious morbidity, and in most cases the patient will require open surgery for management of these complications. The authors report the case of a patient who was ill for 14 months after laparoscopic cholecystectomy when spilled stones formed a nidus for intra-abdominal abscess and colocutaneous fistula. Every effort must be made to prevent gallbladder perforation. When it does occur, all stones should be retrieved. Attempts at repairing gallbladder perforations are often unsatisfactory. A simple solution to this potential problem is to retrieve all stones immediately, place them in an intraperitoneal specimen bag, and "park" the bag on the liver. As soon as the gallbladder is dissected off the liver it should be placed in the specimen bag with the stones and removed through the umbilical port opening.

Radiofrequency ablation in surgery

Recently, hyperthermia has been employed clinically as one of a variety of multimodal therapies for cancer. Hyperthermia has been applied locally, regionally, and systemically to various tumors. Local or regional hyperthermia has the advantage that a localized tumor can be heated to temperatures higher than 420 C, the maximum for total-body hyperthermia. There is mounting evidence to support a hypothesis that cancer cells are more selectively sensitive to heat than are normal cells, due to the poor blood supply of neoplastic tissue and the decreased vasodilatation capacity of the neovascular bed.

Comparison of initial laparoscopic cholecystectomy at a community hospital versus a teaching hospital

OBJECTIVE

To compare the initiation of laparoscopic cholecystectomy at a community hospital versus a tertiary-care teaching hospital.

DESIGN

Retrospective chart review.

SETTINGS

A general community hospital in Prince George, BC, and a tertiary-care teaching hospital in Vancouver.

PATIENTS

One hundred and eighty-two patients in the community hospital and 318 patients in the tertiary-care centre.

INTERVENTION

Laparoscopic cholecystectomy for symptomatic gallbladder disease.

MAIN OUTCOME MEASURES

Preparation of surgeons for the new technique, complication rates, operating time, conversion rates to open cholecystectomy and duration of hospitalization.

RESULTS

All community surgeons took didactic and laboratory courses in preparation for the new procedure and assisted each other for their first 10 cases, but surgeons at the teaching hospital had more varied preparation that included additional extensive laboratory work and preceptorships with surgeons experienced with the procedure. The rates of major complications of laparoscopic cholecystectomy were 6.5% at the community hospital compared with 5% at the tertiary-care centre. The rates of minor complications were 5.5% at community hospital and 5.3% at the tertiary-care centre. The rates of conversion to open cholecystectomy were 6.6% for the community hospital versus 4.7% for teaching hospital. The mean (and standard deviation) operating time was shorter at the community hospital than at the teaching hospital: 72.3 (30) minutes versus 106 (32) minutes (p < 0.0001). The mean (SD) length of stay was 2.5 (1.8) days at the community hospital and 3.4 (1.9) days at the teaching hospital.

CONCLUSIONS

The introduction of laparoscopic cholecystectomy during a 2-year period was achieved safely at both hospitals. The complication rates were similar. The length of stay and operating times were shorter in the community hospital.

Laparoscopic staging of intraabdominal malignancy

Laparoscopic visualization techniques have improved dramatically over the last 5 years and have led to reassessment of the laparoscope for use in the staging of intraabdominal malignancy. One hundred sixty-two consecutive cases undergoing preoperative staging laparoscopy from January 1988 to December 1993 were reviewed in order to determine the value of laparoscopy as a staging tool. Indications for staging laparoscopy were predominantly hepatopancreaticobiliary (85%); however, other primaries such as stomach and colon were included. In 36% of cases information found at laparoscopy precluded resection and prevented unnecessary laparotomy. Additional information that was felt to be helpful in planning resection was found in 30% of cases. In 12% of cases unresectability was found only at the time of laparotomy and was missed by staging laparoscopy. We conclude that laparoscopy is a useful preoperative staging tool and can help avoid unnecessary laparotomy for intraabdominal malignancy in one-third of patients.

Laparoscopic cholecystectomy: a continuing plea for routine cholangiography

The purpose of this clinical study was to demonstrate the usefulness of routine intraoperative cholangiography (IOC) and the safety of laparoscopic cholecystectomies (LC) in a community hospital. There were no ductal injuries and perioperative complications were extremely low. Patients (n = 236) with symptomatic gallstone disease, acalculus cholecystitis, or gallbladder polyps underwent LC from March 1991 to June 1993. During this period two patients were not considered appropriate candidates for this procedure. There were 172 women and 64 men ranging in age from 15 to 84 years. Four had preoperative endoscopic retrograde cholangiopancreatographies (ERCPs) for suspected choledocholithiasis. Elective LC was performed on 194 patients and emergency LC on 42 patients. The average operating time for elective LCs was 89 min and 97 min for emergency LCs. Thirty-six percent of patients had previous abdominal or pelvic surgery. IOC was attempted in 99% of patients and successful in 89%. Five percent had choledocholithiasis. Laparoscopic duct exploration was performed on four patients. Six patients had postoperative ERCP with stone extraction. Three percent of elective patients had additional surgery. One patient had LC during pregnancy (17 weeks), with a normal recovery and successful outcome of the pregnancy. Six elective and four emergency patients were converted to open cholecystectomy, a conversion rate of 4%. There were no ductal or vascular injuries, intraoperative haemorrhages or deaths. There were one small bowel laceration (0.4%). Postoperative complications included seven wound infections (3%), four bile leaks (2%), three trocar site haemorrhages (1%), one intraabdominal haemorrhage (0.4%), one suspected halothane hepatitis (0.4%), one drug-induced cholestatic jaundice (0.4%), and one subcutaneous emphysema (0.4%).(ABSTRACT TRUNCATED AT 250 WORDS)

Laparoscopic surgery: surgical education in the People's Republic of China

In 1991, because of the international emphasis on laparoscopic surgery, a large contingency of surgeons took on the task of introducing laparoscopy to the People's Republic of China. This trip was a technological feat, since all of the equipment and instrumentation had to be carried into the country. This necessitated a major coordinated effort among professional teaching staff and industry representatives with their transported equipment. This unique educational opportunity is detailed in this article, which highlights, in particular, the contrast between the new "high-tech" surgery and the reality of a developing country.

Three-dimensional endoscopic imaging for minimal access surgery

Three-dimensional endoscopic imaging (3DEndoImaging) is a significant technological advance and has the potential to make minimal access surgery (MAS) easier, quicker, less prone to error and more applicable to advanced procedures. Surgeons involved in MAS will need to have a working knowledge of 3DEndoImaging. This article will enable surgeons to compare stereo systems and evaluate which system would best suit their needs. This paper explains why stereo imaging is important and describes the methods by which stereo images can be produced. The technology required is discussed in simple terms. The types of stereo systems are described and important operational and maintenance issues discussed. Task analysis studies showing significant improvement in performance in stereo are presented. These studies simulated accurately positioning an instrument and threading a small diameter solder lug.

[Successful surgical management of arterio-mesenterial duodenal compression]

A 17 year old female patient developed in 6 month a gradually exacerbating stomach passage disturbance not responding to conservative treatment. Clinical and radiological examinations verified that the compression of the duodenum was caused by irregular position of the arteria mesenterica superior. The patient was operated on and a dissection and transposition of the duodenum was performed using an end-to-end anastomosis before the arteria mesenterica superior. This method has never been seen in Hungary before. The good result of the operation was verified by the control examinations.

Laparoscopic cholecystectomy: strategy and concerns

After briefly describing the first laparoscopic cholecystectomy performed by Philippe Mouret, the authors review some of the differences in strategy, management and concerns between conventional and laparoscopic cholecystectomy. They address the problems relating to the required skills of triangulation and camera handling, the presence of common-duct stones and concomitant disease, the issues of drainage, hemostasis, access in difficult cases, iatrogenic trauma to the bile ducts and pertinent differences in cardiorespiratory function.

Laparoscopic surgery--basic armamentarium

The introduction of laparoscopic techniques into standard intracavitary surgery has received widespread acceptance in North American surgical practice in a very short time. To complete these procedures successfully a basic armamentarium is required by surgeons. The equipment should provide safe conduct of the procedure and maximum flexibility in the types of surgical procedures to be undertaken. The basic laparoscopic equipment needed to facilitate minimal-access-site surgery is reviewed, from the operating table and lighting in the operating room through optics, cameras and television monitors to the instruments and agents needed for the surgical techniques and for securing hemostasis.

Laparoscopic cholecystectomy: trans-Canada experience with 2201 cases

The authors carried out a prospective review of the initial and consecutive experience with laparoscopic cholecystectomy of 58 surgeons from 31 teaching and nonteaching institutions throughout Canada. The perioperative morbidity of 2201 cases is described, with special attention to iatrogenic complications. The data suggest that complications, including bile-duct injury, are not frequent. Pneumonia and wound infection rates appear lower than after open surgery. There were no deaths. Laparoscopic cholecystectomy is replacing open cholecystectomy for the management of symptomatic cholelithiasis.

History of laparoscopic surgery

Since the beginning of the 20th century physicians have promoted laparoscopy as a valuable adjunct to the diagnosis of diseases of the abdominal cavity. Laparoscopy, however, failed to become popular among abdominal surgeons until the advent of laparoscopic cholecystectomy. This single new operative approach to the treatment of gallbladder stones gave rise to such enthusiasm among general surgeons that other innovative laparoscopic procedures are now being promoted in ever-increasing numbers. The general surgeon has again become the leader in the introduction of a new surgical approach. This new technique must be developed with great care, and there must be rigorous criteria for its use, critical analysis of the technique and honest reporting of results.

Palliative treatment of advanced colorectal carcinoma with the YAG laser

The Nd-YAG laser was used to provide palliative treatment for eight patients (two women and six men), ranging in age from 53 to 76 years, who had locally advanced colorectal cancer. The main indications for treatment were obstruction, bleeding and copious rectal mucus discharge. Only one complication, a Staphylococcus aureus infection, followed the treatment; the infection was easily controlled. The laser treatment was considered to ease the symptoms in five patients, but survival was not influenced by the treatment. This form of palliation must be evaluated in larger numbers of patients to assess its real value in advanced colorectal cancer.

Cecal diverticulitis

Cecal diverticulitis is an uncommon entity. Its operative treatment represents 0.2% of procedures performed for an acute abdomen. The clinical presentation is often indistinguishable from acute appendicitis. At operation, it may be confused with cecal carcinoma. The surgeon must be aware of this condition and be prepared to choose the most appropriate treatment. Local excision has been advocated as the treatment of choice. The authors review 18 cases seen over a 10-year period. In no case was the correct diagnosis made preoperatively. Intraoperatively, a correct diagnosis was made in 12 of the 18. Carcinoma was the next most frequent intraoperative diagnosis (four cases). Twelve of the 18 patients were treated by standard or limited right hemicolectomy. One patient died early in the series of sepsis caused by a perforated diverticulum and one patient had a life-threatening complication. Right hemicolectomy appears to be a safe and effective treatment option for cecal diverticulitis.

Diagnostic laparoscopy

This report examines the value of laparoscopy as a diagnostic aid to one general surgeon. Seventy-seven consecutive patients who underwent this procedure are reported. In 31 patients, laparoscopy was performed for assessment of the cause of acute abdominal pain. Diagnosis was achieved in 28 patients (90 percent) and laparotomy was avoided in 17 (55 percent). Assessment of chronic abdominal pain in 11 patients yielded a diagnostic accuracy in 9 (82 percent) and laparotomy was avoided in 7 (64 percent). In 11 patients with abdominal trauma, diagnostic accuracy was 91 percent (10 of 11 patients) and laparotomy was not required in 6 (54 percent). In 21 patients with intraabdominal malignancy, 14 (67 percent) were accurately assessed, and in 8 (38 percent) formal exploration was spared. Three patients with obscure causes of ascites and jaundice were all accurately assessed without need for laparotomy. Based on our data, we believe the reports in the literature are reproducible by any abdominal surgeon who uses laparoscopy as a diagnostic aid in their practice.

Abdominal injuries associated with the use of seatbelts

The mandatory use of seatbelts has become commonplace in Canada, and such legislation was adopted by the province of British Columbia in 1977. This has provided us with an opportunity to study the effects of seatbelt restraints on accident victims, particularly concerning abdominal injuries. Five hundred sixty-two patient charts were reviewed during a 3-year period. Documented use of seatbelts was found in 126 cases. Thirty-six of these patients underwent laparotomy and form the basis of this study. Compared with previously reported figures for blunt abdominal trauma, there was a high incidence of gastrointestinal injuries (67 percent). In addition, associated lumbar spine injuries were found in a large proportion of patients (19 percent, p less than 0.005). We found an increased risk of spinal injury in patients wearing a lap versus a three-point belt.

Preservation of the spleen using human fibrin seal

Because of the spleen's role in host defence and the recognition of overwhelming post-splenectomy sepsis, the current aim of treatment for splenic injuries is to preserve the spleen. A number of hemostatic agents have been used in an effort to control bleeding but have not proved satisfactory. The authors report the results of an experiment using a two-component fibrin seal on injured rabbit spleens. In female rabbits a longitudinal laceration of the entire spleen was made. After 2 1/2 minutes of continuous hemorrhaging, the spleens were either not treated (5 rabbits) or treated by splenectomy suture repair or fibrin-seal repair. Hemoglobin values were measured preoperatively and 3 days postoperatively. The greatest number of deaths within 14 days occurred in the untreated group. There was no difference in death rate between the treated groups; similarly, there was no difference in blood loss or fall in hemoglobin values. Fewer adhesions formed in the fibrin-seal group than in the others (p less than 0.02). Histopathological examination revealed a greater fibrinoblastic response in the spleens treated with fibrin seal than in the other groups. The authors believe that fibrin seal is an effective and safe hemostatic agent applicable to splenic parenchymal injuries, and that it promotes wound healing and suppresses adhesion formation.

Diagnosis and treatment of choledochocele complicated by choledocholithiasis (case report)

We report a case of choledochocele associated with choledocholithiasis. The patient became symptomatic when a gallstone was trapped within the choledochocele, causing intermittent biliary obstruction. Endoscopic retrograde cholangiography (ERC) provided the diagnosis and endoscopic sphincterotomy was performed for definite nonoperative treatment. The lesion could not be identified on ultrasound even after its demonstration by ERC. The importance of direct cholangiography in the diagnosis of a choledochocele is discussed.

Obstructive jaundice and cholangitis due to choledocholithiasis: treatment by extracorporeal shock-wave lithotripsy

Endoscopic shock-wave lithotripsy, although now the standard treatment of urolithiasis, has only recently been applied to cholelithiasis. The authors describe the case of an 88-year-old man, a high-risk patient with choledocholithiasis, in whom endoscopic stone extraction after sphincterotomy failed. Extracorporeal shock-wave lithotripsy was used for noninvasive stone fragmentation and the fragments were passed without complication.

Segmental biliary obstruction: false-negative diagnosis with direct cholangiography without US guidance

Segmental intrahepatic ductal obstruction with calculi can be a significant cause of acute cholangitis that may remain entirely undetected on a routine, "blind" direct cholangiogram. Ultrasonography (US) or computed tomography can demonstrate isolated intrahepatic ductal dilatation with or without calculi. US, in particular, can be used to direct the needle puncture for percutaneous transhepatic cholangiography (PTC) and thus enable the differential diagnosis and appropriate therapy to be determined. Four cases are reported in which US-guided PTC enabled confirmation of the diagnosis of acute cholangitis secondary to segmental biliary obstruction and intrahepatic calculi. In two the correct diagnosis could not be made with initial blind direct cholangiography, and in the other two, US and US-guided PTC were performed initially.