Technique of ultrasound examination during laparoscopic cholecystectomy

Ultrasound for Intra-Operative Detection of Peri-Centimetric Pulmonary Nodules in Uniportal Video-Assisted Thoracic Surgery (VATS): A Comparison with Conventional Techniques in Multiportal VATS

Background: Video-assisted thoracic surgery (VATS) has become the gold-standard approach for lung resections. Given the impossibility of digital palpation, we witnessed the progressive development of peri-centimetric and deeply located pulmonary nodule alternative detection techniques. Intra-operative lung ultrasound is an increasingly effective diagnostic method, although only a few small studies have evaluated its accuracy. This study analyzed the effectiveness and sensitivity of uniportal VATS with intra-operative lung ultrasound (ILU), in comparison to multiportal VATS, for visualizing solitary and deep-sited pulmonary nodules. Methods: Patient data from October 2021 to October 2023, from a single center, were retrospectively gathered and analyzed. In total, 31 patients who received ILU-aided uniportal VATS (Group A) were matched for localization time, operative time, sensitivity, and post-operative complications, with 33 undergoing nodule detection with conventional techniques, such as manual or instrumental palpation, in multiportal VATS (Group B). Surgeries were carried out by the same team and ILU was performed by a certified operator. Results: Group A presented a significantly shorter time for nodule detection [median (IQR): 9 (8-10) vs. 14 (12.5-15) min; p < 0.001] and operative time [median (IQR): 33 (29-38) vs. 43 (39-47) min; p < 0.001]. All nodules were correctly localized and resected in Group A (sensitivity 100%), while three were missed in Group B (sensitivity 90.9%). Two patients in Group B presented with a prolonged air leak that was conservatively managed, compared to none in Group A, resulting in a post-operative morbidity rate of 6.1% vs. 0% (p = 0.16). Conclusions: ILU-aided uniportal VATS was faster and more effective than conventional techniques in multiportal VATS for nodule detection.

Ultrasound location of pulmonary nodules in video-assisted thoracoscopic surgery for precise sublobectomy

BACKGROUND

We investigated the clinical value of accurate sublobectomy of pulmonary nodules using video-assisted thoracoscopy (VATS). In June 2017 to June 2019, single lung nodule patients who accepted thoracoscopic resection were included. Palpation and intraoperative ultrasound (IU) were used to localize lung nodules, and the success rate, location time and safety compared. Performance of lung nodule ultrasound was assessed. The success rate of IU localization of pulmonary nodules with different properties was studied.

RESULTS

A total of 33 cases with single pulmonary nodules were included in the study, and 32 cases (97%) were successfully located by IU as opposed to 16 cases (48.5%) located by palpation (P < 0.05). Clear hypoechoic ultrasound images of nodules were obtained in all 32 cases, and the diameter of pulmonary nodules on ultrasound and CT were found to have a significant correlation (R = 0.860, P = 0.000). The average positioning time of IU was lower than that of the palpation group (P < 0.05). No complications occurred during ultrasound examination. The success rate of intraoperative ultrasonic localization between the pure ground-glass opacity (p-GGO) group and the mixed-ground-glass opacity (m-GGO) group was 90%, 100% (P = 0.526).

CONCLUSIONS

In thoracoscopic surgery, IU can locate pulmonary nodules accurately, efficiently and safely, and also has a high degree of accuracy in locating different types of pulmonary nodules.

Ultrasound for intraoperative localization of lung nodules during thoracoscopic surgery

In low-dose CT screening era, an ideal preoperative localization method is essential for resection of small and deep-seated pulmonary nodules by video-assisted thoracoscopic surgery (VATS). This article focuses on intraoperative ultrasonography localization method during thoracoscopy. Performing ultrasonography intraoperatively is a real-time and alternative approach to localize small, non-visible and non-palpable pulmonary lesions without injury to lung parenchyma. Its widespread usage has been limited due to the air in the lung parenchyma; however, its application can be useful in some conditions with guidance to find the lesion.

Meta-analysis of the diagnostic accuracy of laparoscopic ultrasonography and intraoperative cholangiography in detection of common bile duct stones

Introduction During laparoscopic cholecystectomy, intraoperative cholangiography (IOC) is currently regarded as the gold standard in the detection of choledocholithiasis. Laparoscopic ultrasonography (LUS) is an attractive alternative with several potential advantages. Methods A systematic review was undertaken of the published literature comparing LUS with IOC in the assessment of common bile duct (CBD) stones. Results Twenty-one comparative studies were analysed. There were 4,566 patients in the IOC group and 5,044 in the LUS group. The combined sensitivity and specificity of IOC in the detection of CBD stones were 0.87 (95% confidence interval [CI]: 0.83-0.89) and 0.98 (95% CI: 0.98-0.98) respectively with a pooled area under the curve (AUC) of 0.985 and a diagnostic odds ratio (OR) of 260.65 (95% CI: 160.44-423.45). This compares with a sensitivity and specificity for LUS of 0.90 (95% CI: 0.87-0.92) and 0.99 (95% CI: 0.99-0.99) respectively with a pooled AUC of 0.982 and a diagnostic OR of 765.15 (95% CI: 450.78-1,298.76). LUS appeared to be more successful in terms of coming to a clinical decision regarding CBD stones than IOC (random effects, risk ratio: 0.95, 95% CI: 0.93-0.98, df=20, z=-3.7, p<0.005). Furthermore, LUS took less time (random effects, standardised mean difference: 0.95, 95% CI: 0.93-0.98, df=20, z=-3.7, p<0.005). Conclusions LUS is comparable with IOC in the detection of CBD stones. The main advantages of LUS are that it does not involve ionising radiation, is quicker to perform, has a lower failure rate and can be repeated during the procedure as required.

Intraoperative ultrasonographic localization of pulmonary ground-glass opacities

OBJECTIVES

Ground-glass opacities are typically difficult to inspect and to palpate during video-assisted thoracic surgery. We therefore examined whether ultrasonographic assessments could localize ground-glass opacities and help to achieve adequate resection margins.

METHODS

An intraoperative ultrasonographic procedure was prospectively performed on 44 patients harboring ground-glass opacities of less than 20 mm in diameter to localize these lesions and to achieve adequate margins. We also examined whether there were any complications resulting from the intraoperative ultrasonogram, such as lung injury, heart injury, or arrhythmia. We excluded patients with both asthma and chronic obstructive pulmonary disease from this study inasmuch as the intraoperative ultrasonographic procedure is more difficult to interpret when residual air is present in the lung.

RESULTS

A total of 53 ground-glass opacities were successfully identified by intraoperative ultrasonography without any complications. Of the 20 mixed ground-glass opacities that we examined, 15 were found on palpation. However, only 4 (12.1%) of the 33 pure ground-glass opacities could be palpated. In all instances in which complete collapse of the lung was achieved (30/53 of these cases), high-quality echo images were obtained. Additionally, a strong correlation was found between the resection margins measured by ultrasonogram and the margins determined by histologic examination in the resected lung specimens (r(2) = 0.954, P < .001).

CONCLUSIONS

Intraoperative ultrasonography can both safely and effectively localize pulmonary ground-glass opacities in a completely deflated lung. This procedure is also useful for the evaluation of surgical margins in a resected lung. Hence, ultrasonography may assist surgeons to perform minimally invasive lung resections with clear surgical margins during the treatment of solitary lung ground-glass opacity.

The routine use of laparoscopic ultrasound decreases bile duct injury: a multicenter study

OBJECTIVE

Laparoscopic ultrasound (LUS) has been used for over 15 years to screen the bile duct (BD) for stones and to delineate anatomy during laparoscopic cholecystectomy (LC). LUS as a modality to prevent BD injury has not been investigated in a large series. This study evaluated the routine use of LUS to determine its effect on preventing BD injury.

METHODS

A multicenter retrospective study was performed by reviewing clinical outcome of LC in which LUS was used routinely.

RESULTS

In five centers, 1,381 patients underwent LC with LUS. LUS was successful to delineate and evaluate the BD in 1,352 patients (98.0%), although it was unsuccessful or incomplete in 29 patients (2.0%). LUS was considered remarkably valuable to safely complete LC, avoiding conversion to open, in 81 patients (5.9%). The use of intraoperative cholangiography (IOC) varied depending on centers; IOC was performed in 504 patients (36.5%). For screening of BD stones (which was positive in 151 patients, 10.9%), LUS had a false-positive result in two patients (0.1%) and a false-negative result in five patients (0.4%). There were retained BD stones in three patients (0.2%). There were minor bile leaks from the liver bed in three patients (0.2%). However, there were no other BD injuries including BD transection (0%). Retrospectively, IOC was deemed necessary in 25 patients (1.8%) to complete LC in spite of routine LUS.

CONCLUSION

LUS can be performed successfully to delineate BD anatomy in the majority of patients. The routine use of LUS during LC has obviated major BD injury, compared to the reported rate (1 out of 200-400 LCs). LUS improves the safety of LC by clarifying anatomy and decreasing BD injury.

Der laparoskopische Ultraschall

Laparoscopic ultrasound exploration has significantly augmented the range of minimally invasive surgery. In particular it is essential for 3D exploration of the abdomen for staging. Beyond its diagnostic, purposes laparoscopic ultrasound is gaining importance for intraoperative therapeutic support, e. g. imaging of the biliary tree during laparoscopic surgery of the bile duct and for navigation during radio-frequency ablative or resective interventions on the liver and other parenchymatous organs. Compared to other imaging procedures, sonography has still the highest potential for further development. The most progress can be expected in navigated ultrasound.

Intraoperative ultrasonography in open and laparoscopic abdominal surgery: an overview

This article reviews the current state of intraoperative ultrasonography in open surgery (IOUS) and laparoscopic surgery (LUS). The review is based on extensive study of data published (Pubmed search) and on 25 years of personal experience with intraoperative ultrasonography. The main application areas of IOUS and LUS and its use during liver, biliary tract, and pancreatic surgery are discussed. The benefits and limitations as well as future expectations with regard to the existing and emerging applications also are discussed. New developments in ultrasound technology and the increasing experience of surgeons in ultrasonography secure the future for IOUS and LUS.

Laparoscopic ultrasonography is a complement to cholangiography for the detection of choledocholithiasis at laparoscopic cholecystectomy

Background

Intraoperative cholangiography and laparoscopic ultrasonography are both used in the detection of common bile duct stones at laparoscopic cholecystectomy. The aim of this prospective study was to determine whether laparoscopic ultrasonography has an alternative or a complementary role with respect to cholangiography in achieving this end.

Methods

The biliary trees of 900 patients undergoing laparoscopic cholecystectomy were examined routinely by the two methods. The diagnostic power of each investigation and of the two techniques in combination was evaluated. The statistical non-random concordance between the two methods was also determined.

Results

Laparoscopic ultrasonography was performed in all 900 patients. Cholangiography was performed in 762 (85 per cent). The mean (range) duration was 9·8 (4–21) min for laparoscopic ultrasonography and 17·6 (7–42) min for cholangiography. For the detection of common bile duct stones, with a kappa coefficient of 0·57 (95 per cent confidence interval (c.i.) 0·43 to 0·71), the non-random concordance between the two methods was considered to be fair to good. The sensitivity of laparoscopic ultrasonography was 0·80 (95 per cent c.i. 0·65 to 0·91) and its specificity was 0·99 (95 per cent c.i. 0·98 to 1·00). The respective values for cholangiography were 0·75 (95 per cent c.i. 0·59 to 0·87) and 0·99 (95 per cent c.i. 0·98 to 1·00). The examinations combined had a sensitivity of 0·95 (95 per cent c.i. 0·86 to 0·99) and a specificity of 0·98 (95 per cent c.i. 0·96 to 1·00).

Conclusion

Laparoscopic ultrasonography and intraoperative cholangiography are complementary, as the combination of both methods maximizes the intraoperative detection of choledocholithiasis.

História da ultra-sonografia intra-operatória

A ultra-sonografia intra-operatória foi realizada especialmente a partir de 1960, com alguns relatos de experiências iniciais nos anos 50. Inicialmente foram avaliados tumores cerebrais, posteriormente estudando-se também cálculos de vias biliares e cálculos renais. Entretanto, a ultra-sonografia intra-operatória em modo A ou modo B estático não adquiriu grande aceitação no meio médico. Não obstante, os primeiros estudos forneceram as bases para o desenvolvimento da moderna ultra-sonografia intra-operatória, com a utilização dos equipamentos ultra-sonográficos em modo B em tempo real. Os autores discorrem sobre a utilização da ultra-sonografia intra-operatória desde o seu início até os dias atuais.

Prevalence and laparoscopic ultrasound patterns of choledocholithiasis and biliary sludge during cholecystectomy

A prospective study of laparoscopic ultrasound (LUS) for evaluation of the common bile duct during laparoscopic cholecystectomy was started in October 1993. LUS during cholecystectomy was performed routinely to preoperatively identify unsuspected stones. Three-hundred thirty patients with symptomatic cholelithiasis were included in the study. The preoperative work-up included endoscopic retrograde cholangiopancreatography in 49 patients. Common bile duct (CBD) stones were found in 22 cases; in 19 cases the stones were removed successfully by endoscopic sphincterotomy. LUS successfully visualized the CBD in all but 10 patients (3%). CBD stones were found in 17 patients and confirmed by preoperative cholangiography and/or CBD exploration. There were two false-negative and one false-positive result for LUS. In 47 patients (14.2%) LUS detected CBD sludge as low-amplitude echoes without acoustic shadowing. The presence of CBD sludge was correlated with some biochemical and clinical variables. A significant correlation was identified between the absence or presence of CBD sludge and endoscopic retrograde cholangiopancreatography, acute pancreatitis, gallbladder sludge, age, and the levels of serum bilirubin and alkaline phosphatase. A significant difference was recorded between CBD diameter and the presence or absence of stones or sludge (p = 0.00001). In our experience, LUS allowed good diagnosis of CBD stones during laparoscopic cholecystectomy. The clinical significance of CBD sludge remains to be elucidated.

Prevalence and laparoscopic ultrasound patterns of choledocholithiasis and biliary sludge during cholecystectomy

A prospective study of laparoscopic ultrasound (LUS) for evaluation of the common bile duct during laparoscopic cholecystectomy was started in October 1993. LUS during cholecystectomy was performed routinely to preoperatively identify unsuspected stones. Three-hundred thirty patients with symptomatic cholelithiasis were included in the study. The preoperative work-up included endoscopic retrograde cholangiopancreatography in 49 patients. Common bile duct (CBD) stones were found in 22 cases; in 19 cases the stones were removed successfully by endoscopic sphincterotomy. LUS successfully visualized the CBD in all but 10 patients (3%). CBD stones were found in 17 patients and confirmed by preoperative cholangiography and/or CBD exploration. There were two false-negative and one false-positive result for LUS. In 47 patients (14.2%) LUS detected CBD sludge as low-amplitude echoes without acoustic shadowing. The presence of CBD sludge was correlated with some biochemical and clinical variables. A significant correlation was identified between the absence or presence of CBD sludge and endoscopic retrograde cholangiopancreatography, acute pancreatitis, gallbladder sludge, age, and the levels of serum bilirubin and alkaline phosphatase. A significant difference was recorded between CBD diameter and the presence or absence of stones or sludge (p = 0.00001). In our experience, LUS allowed good diagnosis of CBD stones during laparoscopic cholecystectomy. The clinical significance of CBD sludge remains to be elucidated.

Routine intraoperative laparoscopic ultrasonography with selective cholangiography reduces bile duct complications during laparoscopic cholecystectomy

BACKGROUND

Laparoscopic cholecystectomy (LC) is the preferred treatment for gallstone disease, even in many complicated cases. Perhaps the only downside to LC is a two- to threefold increase in common bile duct (CBD) injuries compared with open cholecystectomy (OC). Intraoperative cholangiography may prevent inj uries, but its routine use remains controversial. Our institution adopted a policy of selective intraoperative cholangiography in 1993. When intraoperative laparoscopic ultrasonography (IOUS) emerged as a viable diagnostic adjunct, it was hypothesized that the routine use of IOUS would facilitate dissection, detect occult choledocholithiasis, and prevent bile duct injuries during LC.

STUDY DESIGN

The experience with LC at our university-affiliated teaching hospital was reviewed. Over a 4 1/2-year period (June 1, 1995, to January 31, 2000), two surgeons used IOUS routinely during LC (ultrasonography [US] group, n = 248); three other surgeons did not (non-US group, n = 594). We compared patient data and outcomes between the two groups. Continuous, data are expressed as mean +/- SEM.

RESULTS

During the study period, 842 LCs were attempted. Patient age (37+/-1 years) and gender (85% female) did not differ between the groups. In the US group, more patients had acute cholecystitis (p < 0.05). More LCs were performed per year by non-US surgeons than US surgeons (45 versus 37). Despite this, all bile duct complications occurred in non-US cases (2.5% overall): five CBD injuries (0.8%), six bile leaks (1%), and four retained CBD stones (0.7%). In the subgroup of patients with acute cholecystitis, there were fewer conversions to OC in US compared with non-US cases (24% versus 36%, p = 0.09).

CONCLUSIONS

IOUS is noninvasive, fast, repeatable, and can corroborate real-time visualization of the operative field. We have found that LC with IOUS is associated with fewer bile duct complications (CBD injuries, bile leaks, and retained CBD stones) than LC without adjunctive imaging. The success rate of LC in cases of acute cholecystitis is slightly higher when IOUS is used as an aid to dissection. In the absence of definitive prospective data, we recommend routine use of IOUS when performing LC, particularly in patients with acute cholecystitis.

A critical analysis of intraoperative time utilization in laparoscopic cholecystectomy

BACKGROUND

Most of the expense of laparoscopic cholecystectomy (LC) is incurred while the patient is in the operation room; however, heretofore there has been no critical analysis of the time required to perform the various steps of the operation. An understanding of how operative time is used is the first step toward improving the efficiency of the procedure and decreasing costs while maintaining an acceptable standard of care.

METHODS

Of 194 patients undergoing LC at a university hospital between 1994 and 1997, operational videotapes of 48 randomly chosen patients were reviewed. Three groups of patients were identified: those undergoing LC for chronic cholecystitis (n = 27), those undergoing LC for acute cholecystitis (n = 11), and those with common bile duct stones (CBDS), (n = 10) undergoing LC with transcystic common bile duct exploration. The procedure was divided into the following seven steps; trocar entry, laparoscopic ultrasound, dissection of the triangle of Calot, cholangiogram, dissection of the gallbladder, extraction of the gallbladder, and irrigation-aspiration with removal of ports. Time spent for camera cleaning, bleeding control, and insertion of the cholangiocatheter into the cystic duct was also calculated. The groups were compared in terms of time spent for each step using the Kruskal-Wallis and Mann-Whitney U tests.

RESULTS

The mean +/- SD operating time was 66.5 +/- 20.5 min. The acute group had the longest operating time, followed by the CBDS and chronic groups. Dissection of the gallbladder, insertion of the cholangiocatheter, and irrigation-aspiration were longer steps in the acute group than in the other groups (p < 0.05). Dissection of the triangle of Calot took longer in acute cholecystitis than in chronic cholecystitis (p < 0.05). CBDS cases took longer (p < 0.05) than chronic cases because stone extraction added an average of 17.5 min to the time required for the cholangiogram in chronic cholecystitis. Laparoscopic ultrasound took longer in the CBDS group than in the other groups (p < 0.05). The mean +/- SD time spent for the cholangiogram and laparoscopic ultrasound in chronic cholecystitis was 7.5 +/- 4.3 and 4.8 +/- 1.9 min, respectively.

CONCLUSIONS

This time analysis study demonstrates that acute cholecystitis requires a longer operating time because most of the individual steps in the procedure take longer. In patients with choledocholithiasis, stone extraction was responsible for longer operating times. This study should serve as a basis for future studies focusing on time utilization in laparoscopic surgery.

The prevention of bile duct injury during laparoscopic cholecystectomy from the point of view of anatomic variation

The aim of this study was to evaluate ways to prevent bile duct injury during laparoscopic cholecystectomy in patients with anomalous biliary tract anatomy. The biliary tract was studied using cholangiograms of 511 patients who had gallbladder disease and was dissected in 92 cadaveric specimens. The authors classified confluent forms of the cystic duct and the bile duct into five different types, including four anomalous types. Sixteen instances (3.13%) of anatomic variation of the biliary tract were found among the patients, and four cases (4.35%) were found in the cadavers. Among the 511 patients, there were 495 cases of type C anatomy, three cases of type A, seven cases of type R, six cases of type P, and zero cases of type L; among the 92 cadaveric specimens, there were 88 cases of type C anatomy, one case of type R, two cases of type P, and one case of type L. For anatomic types A, P, and R, there is a high probability of risk of cutting the wrong duct. Therefore, it is important to clarify the anatomy of the biliary tract by preoperative examination and to carefully dissect the cystic duct close to the neck of the gallbladder during laparoscopic cholecystectomy. Anatomic variation of the biliary tract is common and can create a rare pitfall during laparoscopic cholecystectomy.

A comparison of laparoscopic ultrasound versus cholangiography in the evaluation of the biliary tree during laparoscopic cholecystectomy

OBJECTIVE

This study assessed the effectiveness of laparoscopic ultrasound in detecting main biliary duct stones.

METHODS

From November 1994 to August 1998, 600 patients treated by laparoscopic cholecystectomy were included in a prospective study, to compare intraoperative cholangiography and laparoscopic ultrasound. The biliary tree was successively explored by these two methods in the routine detection of common bile duct stones.

RESULTS

The feasibility of laparoscopic ultrasound was 100%. Cholangiography was performed only in 498 cases (83%). The time taken for laparoscopic ultrasound examination was significantly shorter (10.2 vs 17.9 min, P=0.0001). In this study, common bile duct stones were found in 54 cases (9%). For their detection, results were comparable to laparoscopic ultrasound and intraoperative cholangiography. For laparoscopic ultrasound, sensitivity was 80% and specificity 99%; and for cholangiography 75 and 98% respectively. Both examinations combined had a 100% sensitivity and specificity. Laparoscopic ultrasound failed to recognize the intrapancreatic part of the common bile duct in 78 cases (13%) and did not show anatomical anomalies detected by cholangiography. It did however detect other unsuspected intra-abdominal pathologies.

CONCLUSIONS

Laparoscopic ultrasound is safe, repeatable, and non-invasive, but a considerable learning curve is necessary to optimize its efficacy. Comparison of relative cost must be undertaken.

Intraoperative ultrasound during thoracoscopic procedures for solitary pulmonary nodules

BACKGROUND

Traditional nonoperative diagnostic approaches to the solitary pulmonary nodule (bronchoscopy and percutaneous needle biopsy) can be inconclusive. Video-assisted thoracic surgery (VATS) provides a minimally invasive way to diagnose and treat these nodules. We evaluated the use of a dedicated intraoperative ultrasound probe as an aid in localization of small pulmonary nodules during VATS.

METHODS

An intraoperative ultrasound examination during a thoracoscopic procedure was performed on 18 patients to localize deep pulmonary nodules less than 20 mm in diameter without a definitive diagnosis by preoperative imaging techniques.

RESULTS

In the 18 patients, all nodules were successfully identified by intraoperative ultrasound. A definitive pathologic diagnosis was obtained from thoracoscopic biopsy or resection. The final diagnoses were primary lung cancer in 5 patients, metastatic lesions in 4 patients, hamartoma or chondroma in 4, granuloma in 3, and interstitial fibrosis in 2 patients.

CONCLUSIONS

In our experience, intraoperative ultrasound can safely and effectively localize invisible or nonpalpable pulmonary nodules at the time of thoracoscopy. This may help surgeons perform minimally invasive lung resections with clear surgical margins.

Laparoscopic ultrasonography versus operative cholangiography during laparoscopic cholecystectomy: review of the literature and a comparison with open intraoperative ultrasonography

BACKGROUND

Laparoscopic ultrasonography (LUS) has been used increasingly over the last several years as a new imaging modality. To define the role of LUS during laparoscopic cholecystectomy, we evaluated LUS by prospectively comparing it with operative cholangiography (OC), by reviewing the literature on LUS, and by retrospectively comparing it with intraoperative ultrasonography performed during open cholecystectomy.

STUDY DESIGN

LUS and OC were compared prospectively in 100 consecutive patients during laparoscopic cholecystectomy. The success rate of examination, the time required, the accuracy in diagnosing bile duct calculi, and the delineation of biliary anatomy were evaluated.

RESULTS

The success rate of examination was 95% for LUS and 92% for OC. The main reason for unsatisfactory LUS was incomplete visualization of the distal common bile duct. The time required was 8.2 minutes for LUS and 15.9 minutes for OC (p<0.0001). Nine patients had bile duct calculi. LUS had one false-negative result and OC had two false-positives and one false-negative. The accuracies of LUS and OC were comparable except for a slightly better positive predictive value of LUS (100% versus 77.8%; p>0.1). In a literature review, 12 recent prospective studies comparing LUS and OC and three studies on open intraoperative ultrasonography were reviewed. Twelve studies of LUS with a total of 2,059 patients demonstrated results similar to the present study. The success rate was 88% to 100% for both tests. The time for LUS was approximately 7 minutes, about half of the time needed for OC. Overall, LUS was associated with fewer false-positive results than OC; the positive predictive value and specificity of LUS were better, while the sensitivity and negative predictive value of LUS and OC were comparable. OC detected ductal variations or anomalies more distinctly than LUS. Compared with open intraoperative ultrasonography, LUS had a slightly lower success rate and required a slightly longer time because it was technically more demanding, but the two procedures had a similar accuracy for diagnosing bile duct calculi.

CONCLUSIONS

Because of their different advantages and disadvantages, LUS and OC can be used in a complementary manner. There is a learning curve for LUS because of its technical difficulty. Once learned, however, LUS can be used as the primary screening procedure for bile duct calculi because of its safety, speed, and cost-effectiveness. OC can be used selectively, particularly when ductal anatomic variations or anomalies or bile duct injuries are suspected.

History of intraoperative ultrasound

Intraoperative ultrasound (IOUS) using A-mode or non-real-time B-mode imaging started in the 1960s; however, it was not widely accepted mainly because of difficulty in image interpretation. In the late 1970s, IOUS became one of the topics in the surgical communities upon the introduction of high-frequency real-time B-mode ultrasound. Special probes for operative use were developed. In the 1980s, all over the world the use of IOUS spread to a variety of surgical fields, such as hepatobiliary pancreatic surgery, neurosurgery, and cardiovascular surgery. IOUS changed hepatic surgery dramatically because IOUS was the only modality that was capable of delineating and examining the interior of the liver during surgery. After 1990, color Doppler imaging and laparoscopic ultrasound were incorporated into IOUS. Currently, IOUS is considered an indispensable operative procedure for intraoperative decision-making and guidance of surgical procedures. For better surgical practice, education of surgeons in the use of ultrasound is the most important issue.

Evaluation of the biliary tree during laparoscopic cholecystectomy: laparoscopic ultrasound versus intraoperative cholangiography: a prospective study of 150 cases

From November 1994 to March 1996, 150 patients treated by laparoscopic cholecystectomy were included in a prospective study, to compare intraoperative cholangiography (IOC) and laparoscopic ultrasonography (LU). The biliary tree was successively explored by these two methods in the routine detection of common bile duct stones. The feasibility of LU was 100%. Cholangiography was performed only in 125 cases (83%). The time taken for LU was significantly shorter (11.6 vs. 17.6 minutes, p = 0.0001). In this study, common bile duct stones were found in 14 cases (9%). For their detection, results were comparable to LU and IOC. For LU, sensitivity was 80% and specificity 99%; and for IOC, 78 and 97%, respectively. Both examinations combined had a 100% sensitivity and specificity. Laparoscopic ultrasonography failed to recognize the intrapancreatic part of the common bile duct in 25 cases (17%) and did not show anatomic abnormalities detected by IOC. It did, however, detect other unsuspected intraabdominal abnormalities. Although LU is safe, repeatable, and noninvasive, a considerable learning curve is necessary to optimize its efficacy. Comparison of relative cost must be undertaken.

Ultra-sonografia intra-operatória durante colecistectomia laparoscópica

Durante um período de sete meses, em noventa pacientes submetidos à colecistectomia laparoscópica foi realizada ultra-sonografia intra-operatória e, em 81 pacientes, a colangiografia intra-operatória foi possível. A ultra-sonografia laparoscópica (USL) foi realizada através dos trocartes umbilical e epigástrico, sem mobilização duodenal e após a colangiografia sistemática. A USL detectou coledocolitíase em 11 pacientes (12,2%), embora apenas seis (6,6%) destes pacientes tivessem este diagnóstico antes da cirurgia. A colangiografia diagnosticou coledocolitíase em 8,8% dos casos. As vias biliares foram visualizadas pela USL em todos os casos. Durante a colecistectomia laparoscópica, a ultra-sonografia intra-operatória é uma técnica simples e eficiente na detecção de cálculos na via biliar principal.

The evolution and maturation of laparoscopic cholecystectomy in an academic practice

BACKGROUND

The technique of laparoscopic cholecystectomy (LC) has evolved since its adoption in the late 1980s. We sought to document these changes and assess whether patient outcomes were influenced during this maturational process.

STUDY DESIGN

A prospective data base was used to record the outcomes of all LCs performed in an academic surgeon's practice. Trends over time among 1,165 consecutive patients were assessed by comparing the first 100 LCs (group I), the middle 100 LCs (group II), and the most recent 100 LCs (group III).

RESULTS

During a 93-month period with 1,165 patients undergoing LC, 25 procedures (2.1%) were converted to open cholecystectomy. Perioperative complications occurred in 31 patients (3%): grade I in 9 (0.8%), grade II in 16 (1.4%), grade III in 5 (0.4%), and grade IV (death) in 1 (0.1%). Length of hospital stay and convalescence were 1.1 +/- 0.1 and 9.5 +/- 0.5 days, respectively. Nineteen patients (2%) were readmitted early after operation and 10 (1%) developed long-term complications (port-site hernia or retained stone). In group III, cholangiography was largely replaced by intraoperative ultrasonography for ductal evaluation. Operating room time decreased, while the rates of conversion, morbidity, and readmission remained the same. Patients had higher ASA classifications in the latter two groups, whereas operative charges were greater in Group III than in Groups I and II. These trends occurred even though most procedures are currently performed by residents, and fewer LCs are being done.

CONCLUSIONS

Laparoscopic cholecystectomy has matured into a more efficient operation, yet remains safe with low morbidity when performed by residents at an academic institution.

Intraoperative and laparoscopic ultrasound

Intraoperative ultrasound, whether during celiotomy or laparoscopy, plays an important role in assisting the surgeon in directing appropriate therapy for intra-abdominal diseases, particularly primary or metastatic malignancies involving the liver and primary malignancies of the pancreas and upper gastrointestinal tract. It is the most sensitive imaging technique for detecting small intraparenchymal lesions of the liver, pancreas, and other solid organs. Owing to its increased sensitivity over all commonly used preoperative imaging studies, it is responsible for changing the intraoperative treatment plan of these tumors in a significant percentage of cases. This is particularly true with respect to resectability. In the era of laparoscopic surgery, it replaces the surgeon's inability to palpate the liver and other organs during surgery. As surgeons use a laparoscopic approach with increasing frequency to treat intra-abdominal disease, they will have an increasing need to master the use of intraoperative ultrasound in order to render optimal care to their patients.

The role of intraoperative ultrasonography during laparoscopic adrenalectomy

BACKGROUND

The role of laparoscopic intraoperative ultrasonography (IOUS) in intraoperative decision making has grown rapidly in recent years. The purpose of this study was to evaluate its usefulness during laparoscopic adrenalectomy.

METHODS

Since 1995, laparoscopic ultrasonography has been used to evaluate the adrenal gland and surrounding organs in selective laparoscopic adrenalectomies. IOUS was performed in 19 of 114 laparoscopic adrenalectomies.

RESULTS

IOUS effected a change in management in 68% of these patients. IOUS displayed the location of the gland after a failed attempt at open resection; the adrenal vein, expediting control in four operations; no extraadrenal involvement by two large lesions (benign); vascular invasion in one tumor (carcinoma), prompting open resection; periadrenal invasion by one metastatic cancer and lymph node involvement in another; a 7 mm hyperaldosteronoma; no adenoma in two cases; bilateral hyperplasia; and a 14 cm cyst originating from the adrenal gland. IOUS facilitated partial adrenalectomy in two patients and revealed centrally located adenomas in two others requiring total adrenalectomy.

CONCLUSIONS

Laparoscopic IOUS during adrenal operation is valuable in selected cases. It is helpful to locate the gland and vein, confirm the presence or absence of abnormality, discern the resectability of large masses, and facilitate a partial adrenalectomy when desirable.

The utility of ultrasonography for screening the common bile duct during laparoscopic cholecystectomy

Since the introduction of laparoscopic cholecystectomy, the means by which the common bile duct is evaluated, if performed at all, has been debated. When the common bile duct is to be screened, two primary modalities have emerged. These techniques are fluoroscopic cholangiography and intracorporeal ultrasonography. Fluoroscopic cholangiography during laparoscopic cholecystectomy has been shown to be effective and accurate for demonstrating ductal stones and anomalies. More recently, laparoscopic ultrasonography has been utilized for screening the common bile duct. Ultrasonography is probably more sensitive than cholangiography for demonstrating intraluminal common bile duct stones or sludge and can be performed more rapidly and at less cost than cholangiography. However, ductal anomalies may not be as readily visualized. The two techniques, therefore, appear to be complementary for evaluating the common bile duct during laparoscopic cholecystectomy, and both techniques should be taught to today's surgical trainees.

Operative ultrasound in general surgery

BACKGROUND

Since the introduction of real-time B-mode ultrasound during surgery almost 20 years ago, the use of operative ultrasound (OUS) has gradually expanded to a variety of surgical fields.

METHODS

A review of the history, technology, and specific applications of OUS in general surgery is presented with our clinical results of over 2300 operations.

RESULTS

The benefits provided by OUS are the acquisition of new information not otherwise available, complement to or replacement for operative radiography, confirmation of satisfactory completion of an operation, and guidance of surgical procedures. OUS possesses many advantages as an intraoperative tool, including safety, speed, unique imaging information, wide applicability, high accuracy and procedure guidance capability.

CONCLUSION

OUS is gaining wider acceptance in hepatobiliary, pancreatic, endocrine, and vascular surgery. Newer OUS modalities-color Doppler imaging and laparoscopic ultrasound-potentially may widen the applications of OUS in general surgery.

Intraoperative ultrasonography (IOUS) during laparoscopic cholecystectomy

BACKGROUND

The purpose of this study was to evaluate the usefulness of intraoperative ultrasonography (IOUS), a new method of imaging the biliary tree and related structures, during laparoscopic cholecystectomy.

METHOD

An IOUS probe (Aloka, Tokyo, Japan) with a 7.5-MHz linear-array transducer was used during cholecystectomy in 124 patients with symptomatic cholelithiasis (45 men, 79 women; mean age, 48 +/- 14 years).

RESULTS

The examination of the common bile duct (CBD) was excellent in 117 patients but unsatisfactory in 7 cases (5.6%) at the level of the head of the pancreas. In 5 patients, IOUS showed unsuspected choledocholithiasis: a subsequent intraoperational cholangiogram confirmed this. In five cases IOUS was able to help the surgeon to localize a Calot area obscured by inflammation. Postoperatively, one patient had an injury of the cystic duct stump: a nasobiliary tube resolved the bile leakage after 7 days. Another patient was submitted to postoperative endoscopic retrograde cholangiopancreatography (ERCP) for a choledocholithiasis recognized by a trans-cystic-tube cholangiography: the stone was suspected but not demonstrated either by laparoscopic IOUS or by intraoperative cholangiography. During the follow-up period, one patient had an episode of acute pancreatitis. ERCP showed a small stone wedged in the sphincter of Oddi.

CONCLUSIONS

IOUS may be a real alternative to cholangiography during laparoscopic cholecystectomy since it is safer and offers a complete examination of the biliary tree. It has some disadvantages which can solved by additional experience.

Results of a change to routine fluorocholangiography during laparoscopic cholecystectomy

BACKGROUND

Early in our experience with laparoscopic cholecystectomy (LC), intraoperative cholangiography (IOC) was performed selectively with static imaging techniques. We subsequently changed to routine digital fluorocholangiography (FIOC) and evaluated the results of this strategy.

METHODS

In a consecutive series of 356 LCs, 11 patients (3%) were converted to open cholecystectomy. In the remaining 345 patients FIOC was attempted in 336 patients (97%) and was successfully completed in 328 patients (95%). Results of IOC and outcomes were compared prospectively in patients without indications for IOC (group I, n = 185) with those with criteria for selective IOC (group 2, n = 160) and retrospectively with patients without indications for IOC undergoing static IOC (group 3, n = 56).

RESULTS

Time to perform FIOC was less than for static IOC (14 +/- 1 versus 24 +/- 1 minutes, p < 0.001). Aberrant ductal anatomy was appreciated by using FIOC in 11% but affected operative management in only 3% of patients. Choledocholithiasis was detected in 23 patients (7%) undergoing FIOC; only two of these patients with stones were in Group 1. Duct stones discovered by IOC were cleared laparoscopically in 89% of those attempted (73% of all patients). Neither morbidity nor duct injury caused by FIOC was noted.

CONCLUSIONS

FIOC is much more rapid to perform than static IOC. Digital fluoroscopy is accurate and safe and permits rapid evaluation and management of bile duct stones. Selective use of FIOC efficiently assesses the common duct in the era of LC.

Appraisal of intraoperative ultrasonography during laparoscopic cholecystectomy

BACKGROUND

The usefulness of intraoperative ultrasonography during laparoscopic cholecystectomy (LC) has yet to be evaluated fully.

METHODS

In 50 patients who underwent LC, the intraoperative ultrasonography findings were compared with those of preoperative ultrasonography, intraoperative cholangiography, and histology, and then its usefulness for examining anatomic relationships in the hepatoduodenal ligament, detecting bile duct stones, diagnosing gallbladder polyps and abnormally thickened walls, and determining the propriety of LC was appraised.

RESULTS

The preoperative ultrasonography diagnoses were gallstones in 38 patients, polyps in 10, and cancer and adenomyomatosis in one each. In four patients endoscopic retrograde cholangiography showed bile duct stones. In all 50 patients intraoperative ultrasonography was useful for examining the anatomic relationships between the bile duct and vessels, such as the portal vein and hepatic artery, and showing the presence or absence of bile duct stones. On the basis of the intraoperative ultrasonography findings, gallstones were diagnosed in 38 patients, in five of whom bile duct stones were shown clearly, cholesterol polyps in eight, early-stage cancer or adenoma in two, and adenomyomatosis in two, and subsequently LC was performed. Histologic diagnoses of cholesterol polyps were made in eight of ten patients with polyps, and intramucosal cancer and an inflammatory polyp in one each. In one patient with a preoperative diagnosis of cancer the apparently elevated flat lesion was found to be partial thickening of the gallbladder wall, which was diagnosed as adenomyomatosis, and LC was chosen as the operative procedure.

CONCLUSIONS

Intraoperative ultrasonography during LC is useful for detecting bile duct stones, diagnosing gallbladder polyps and abnormally thickened walls, and deciding whether LC is adequate for resection of the gallbladder.

A comparison of intraoperative ultrasound versus cholangiography in the evaluation of the common bile duct during laparoscopic cholecystectomy

Indications for intraoperative evaluation of the common bile duct during laparoscopic cholecystectomy are controversial, as is the goal of either anatomic definition or assessing for choledocholithiasis. One hundred twenty-five consecutive patients undergoing laparoscopic cholecystectomy underwent both intraoperative ultrasound and intraoperative cholangiography. Cholangiography required slightly more time to perform; it was more sensitive (92.8% vs 71.4%) but less specific (76.2% vs 100%) for choledocholithiasis than was ultrasound. Ultrasound was somewhat more difficult to perform, and, particularly in the setting of intraabdominal obesity, was often inadequate at providing clear visualization of the intrapancreatic common bile duct. It did not provide the same anatomic definition as an adequate cholangiogram. The overall incidence of choledocholithiasis was 11.2%.

[The technique of laparoscopic ultrasound study in diagnostic laparoscopy]

In gastric cancer, retrogastric invasion or enlarged lymph nodes in the hilus of the spleen or at the celiac trunk can readily visualized with laparoscopic ultrasound examination (LUS). Invasion or metastases of the liver can be identified which are "invisible" with the "classic" imaging methods. In our series this led to revision of the TNM staging in 8% of 111 patients with advanced gastric carcinoma. In the staging of early pancreas cancer the standard methods of investigation, including ERCP, are unsatisfactory. Tumor localization, invasion of blood vessels and local or distal lymph node metastases cannot always be evaluated reliably. LUS promises to provide this valuable information. In carcinoma of the distal esophagus or the cardia, LUS can help to exclude small liver metastases, assess invasion of the diaphragm and evaluate the extent of enlarged intraabdominal lymph nodes, especially those at the celiac trunk. A frequent challenge/task for LUS is the exact determination of the benign or malignant nature of liver foci. Quite commonly they are inaccessible to percutaneous CT-guided puncture, but can be easily reached and biopsied under direct vision or LUS-guidance. By virtue of LUS and its information about extrahepatic lymph node infliction, diagnostic laparoscopy is now a less invasive but equally valid substitute for diagnostic laparotomy prior to liver transplantation in oncological diseases. LUS is now well established in diagnostic laparoscopy as a reliable tool for the preoperative staging of distal esophageal and abdominal tumors. It provides additional information which cannot be obtained with conventional imaging procedures.