Intraoperative Laparoscopic Ultrasonography Research Articles

Laparoscopic ultrasonography along with staging laparoscopy as a tool for staging in patients with hepatopancreaticobiliary malignancy - A prospective cohort study from a tertiary care centre.

Staging laparoscopy (SL) plays an important role in avoiding unnecessary non-therapeutic laparotomy in radiologically resectable hepatopancreaticobiliary (HPB) malignancy patients. The limitation of SL is to detect deep-seated malignancy. The addition of laparoscopic ultrasonography for identifying metastatic lesions or locally unresectable disease improves the diagnostic yield of SL. This prospective, observational study was conducted in a single unit of the tertiary care centre between 2017 and 2019. All the patients of HPB malignancy who were radiologically resectable underwent SL and laparoscopic intraoperative ultrasonography. Metastatic disease patients were either underwent palliative bypass procedures or abandoned depending on the condition of the patient. Patients who had resectable disease underwent standard surgical procedures. Forty patients of HPB malignancy with potentially resectable on radiological imaging underwent SL and diagnostic ultrasonography. Out of 40, 21 patients had periampullary, 14 had carcinoma gallbladder and 5 patients had distal cholangiocarcinoma. Metastatic lesions were identified on laparoscopy in eight patients and the diagnostic yield of SL is 20%. Addition of laparoscopic ultrasonography identified one haemangioma which was false positive on laparoscopy and underwent the radical standard procedure. Four patients were unresectable so the procedure was abandoned and another three patients underwent a bypass procedure. Laparoscopic ultrasonography during SL can detect deep-seated metastatic lesions and decide the management in resectable disease.

Intraoperative Laparoscopic Ultrasound Increases Fibroid Detection During Laparoscopic Myomectomy.

Objective:To assess the utility of intraoperative laparoscopic ultrasound in detecting additional fibroids during laparoscopic myomectomy (LM).Methods:Forty-two patients were enrolled in this prospective cohort study. All cases were performed by the same surgeon at a university affiliated hospital between April 1, 2019 and February 29, 2020. Following routine laparoscopic myomectomy, the laparoscopic ultrasound was then introduced, and ultrasonography was performed directly on the uterus. Any additional fibroids discovered were enucleated.Results:Using the laparoscopic ultrasound, an additional 54 fibroids among 27 (64%) of the 42 patients were found, with a median of 2 additional fibroids per patient (interquartile range [IQR] 1,3). Median fibroid size detected by laparoscopic ultrasound was 1.5 centimeters (IQR 1–3) and the most common types were FIGO grades 3 and 2 (43% and 33% respectively). The median surgical time was longer among patients in whom additional fibroids were found (170 minutes (IQR 137–219) vs 150 minutes (IQR 120–193), p = .044). When ≥ 2 fibroids were removed by usual methods, the laparoscopic ultrasound found additional fibroids 80% of the time, compared to 25% when < 2 fibroids were removed by usual methods (p < .001).Conclusion:Intraoperative laparoscopic ultrasonography is a useful tool in detecting additional fibroids that would have otherwise been missed. It is particularly helpful in identifying smaller intramural fibroids and in patients with multiple fibroids. By detecting additional fibroids, laparoscopic ultrasonography can help maximize the effectiveness of laparoscopic myomectomy and help decrease the rates of residual fibroids.

Intraoperative Tumor Localization of Early Gastric Cancers.

Recently, endoscopic screening systems have enabled the diagnosis of gastric cancer in the early stages. Early gastric cancer (EGC) is typically characterized by a shallow invasion depth and small size, which can hinder localization of EGC tumors during laparoscopic surgery. Here, we review nine recently reported tumor localization methods for the laparoscopic resection of EGCs. Preoperative dye or blood tattooing has the disadvantage of spreading. Preoperative 3-dimensional computed tomography reconstruction is not performed in real time during laparoscopic gastrectomy. Thus, they are considered to have a low accuracy. Intraoperative portable abdominal radiography and intraoperative laparoscopic ultrasonography methods can provide real-time feedback, but these methods require expertise, and it can be difficult to define the clips in some gastric regions. Despite a few limitations, intraoperative gastrofibroscopy provides real-time feedback with high accuracy. The detection system using an endoscopic magnetic marking clip, fluorescent clip, and radio-frequency identification detection system clip is considered highly accurate and provides real-time feedback; we expect a commercial version of this setup to be available in the near future. However, there is not yet an easy method for accurate real-time detection. We hope that improved devices will soon be developed and used in clinical settings.

Evaluation of Intraoperative Laparoscopic Ultrasonography to Enhance Fibroid Detection during Laparoscopic Myomectomy

Evaluation of Intraoperative Laparoscopic Ultrasonography to Enhance Fibroid Detection during Laparoscopic Myomectomy

Laparoscopic Liver Surgery Guided by Virtual Real-time CT-Guided Volume Navigation

BackgroundRecently, virtual navigation system has been applied to hepatic surgery, enabling better visualization of intrahepatic vascular branches and location of tumor. Intraoperative ultrasonography (IOUS) is the most common form of image guidance during liver surgery. However, during laparoscopic hepatectomies (LH), IOUS has several limitations and its reliability has been poorly evaluated. The objective of this work is to evaluate VRCT (virtual real-time CT-guided volume navigation) during LH. This system aims to provide accurate anatomical orientation for surgeons enhancing the safety of LH. MethodsTwenty-seven hepatic neoplasms were resected laparoscopically at our institution under reference guidance of VRCT. During operation, electromagnetic tracking of the surgical instrument was used for navigating the direction of accurate liver transection. ResultsTwenty-six (96.3%) of the 27 lesions (mean diameter 11 mm) were successfully performed under VRCT guidance. Average registration time was < 2 min. Average setup time was approximately 7 min per procedure. VRCT allows the surgeon to navigate liver transection with acceptable accuracy. The mean error was 12 mm. All surgical margins were negative and the mean histologic resection margin was 9 mm. ConclusionsVRCT-guided LH is feasible and provides valuable real-time anatomical feedback during hepatic resections. Advancement of such systems to improve accuracy might greatly compensate for the limitation of laparoscopic IOUS.

Laparoscopic intraoperative ultrasonography reduces the need for preoperative MRCP and ERCP in high- and moderate-risk patients with suspected choledocholithiasis

Laparoscopic intraoperative ultrasonography reduces the need for preoperative MRCP and ERCP in high- and moderate-risk patients with suspected choledocholithiasis

Impact value of laparoscopic ultrasound over triphasic computed tomography in the management of hepatic focal lesions

AimIntraoperative ultrasound has an established role in hepatic resections for patients who undergo surgery for potential liver resection. The aim of the present study was to evaluate the impact of laparoscopic intraoperative ultrasonography (LUS) findings compared to pre‐operative triphasic computed tomography (TCT) findings in the management of hepatic focal lesions.Patient and methodsEighty‐seven patients with 192 hepatic focal lesions underwent preoperative TCT and intraoperative LUS evaluation. Data in each case were collected, including number, site and size of hepatic focal lesions.ResultsThere were 112 lesions detected on preoperative TCT, and 80 additional new lesions (42 per cent) were detected in 50 patients, as confirmed by LUS. Twenty‐three lesions (12 per cent) in 20 patients were treated by resection or ablation, and correct staging of the tumours was possible in 61 patients (70 per cent).ConclusionThe use of LUS can be considered a cornerstone for any contemplated hepatic surgery, as it corrects the staging of these lesions. In addition, the present study proved that LUS is more sensitive than TCT in detecting liver tumours, especially smaller lesions and those on the inferior and diaphragmatic surfaces of the liver.

Application of intraoperative ultrasonography in retroperitoneal laparoscopic partial nephrectomy: A single-center experience of recent 199 cases.

Objectives:To summarize the value and application experiences of intraoperative laparoscopic ultrasonography (ILUS) in retroperitoneal laparoscopic partial nephrectomy (RLPN).Materials and Methods:From January 2013 to December 2018, RLPN with ILUS was performed on the recent 199 patients in our center (two patients received bilateral RLPN due to suspected malignancy of both right and left sides), and the relevant clinical and follow-up data were retrospectively reviewed. Among them, 119 patients were male and 80 were female; the age of patients was 53.4 ± 12.3 years. Of all the renal tumors, 105 were located on the left side and 96 on the right side with a RENAL score of 6.6 ± 1.7. All the patients were diagnosed as or suspected of having a renal tumor by preoperative imaging examination. The ILUS was applied in all the operations to help locate the tumor, delineate the boundary, clarify the diagnosis, observe the blood supply, and so on.Results:RLPN with ILUS in these 199 patients was successfully performed without conversion to open surgery. All surgeries were completed in 90.2 ± 21.7 min, with 73.6 ± 89.2 mL for estimated blood loss, and 19.3 ± 5.6 min for warm ischemia time. The tumor size was 3.6 ± 1.5 cm, and all the surgical margins were negative. The drainage days and postoperative hospital days were 4.7 ± 2.3 and 6.1 ± 2.3, respectively. The preoperative creatinine was 69.7 ± 19.4 μmol/L compared with 61.6 ± 12.7 μmol/L measured 1 month postoperatively. There were 17 cases of renal cell carcinoma no more than 1 cm, and they were resected without artery clamp or a large amount of blood loss. Satellite tumors were confirmed in 12 cases, of which 8 were not detected by preoperative examinations and finally found by ILUS during surgeries.Conclusion:ILUS can alleviate the difficulty of preoperative diagnosis, facilitate surgical dissection, and improve the effect of nephron-sparing surgeries. Due to its great advantage, ILUS should further be promoted and applied.

Intraoperative ultrasonography in laparoscopic partial nephrectomy for intrarenal tumors.

ObjectiveTo evaluate the feasibility and efficacy of intraoperative ultrasonography in laparoscopic partial nephrectomy (LPN) for intrarenal tumors.Patients and methodsAll patients who underwent LPN for renal tumors in our institution from January 2010 to October 2016 were assessed retrospectively. Patients were divided into two groups, the first with totally intrarenal tumors (TIT group), defined as a solid renal mass with no exophytic element on both preoperative and intraoperative evaluations, and the second with exophytic tumors (control group). General information and perioperative data of the two groups were compared, including tumor characteristics, operative time, estimated blood loss, warm ischemia time and pathological findings. Intraoperative laparoscopic ultrasonography (ILUS) was used to precisely locate and delineate the TIT border, as well as seeking for other suspected lesions.ResultsWe identified 583 patients who underwent LPN in our center, including 46 in the TIT and 537 in the control group. All patients in the TIT group were evaluated by ILUS, and all TIT procedures were successfully performed with only one conversion to open surgery. The mean tumor sizes in the TIT and control groups were 2.42 ± 0.46 cm and 3.29 ± 1.43 cm (p < 0.001), respectively. The TIT group’s R.E.N.A.L. nephrometry score was higher than that of the control group (median 8.5 vs 6.0, p < 0.001), and their mean operation times were 127.2 ± 16.0 min and 120.1 ± 19.2 min, respectively. Mean estimated blood loss was higher in the TIT than in the control group (161.3 ml vs 136.6 ml, p = 0.003). Mean warm ischemia time differed in the TIT and control groups (22.2 ± 6.4 vs 20.6 ± 4.7 min, p = 0.105), but not significantly. Rates of open conversion and positive margins, as well as rates of major postoperative complications, pathological findings, and 1-month changes in renal function, were similar in the two groups.ConclusionIntraoperative ultrasonography is technically feasible in patients undergoing LPN for TITs. This method may reduce the need for radical nephrectomy in patients with endogenic renal masses.

Changes in duration of action of rocuronium following decrease in hepatic blood flow during pneumoperitoneum for laparoscopic gynaecological surgery

BackgroundA moderate insufflation pressure and deep neuromuscular blockade (NMB) have been recommended in laparoscopic surgery in consideration of the possible reduction in splanchnic perfusion due to the CO2-pneumoperitoneum. Since the liver is the major organ for rocuronium metabolism, the question of whether NMB of rocuronium would change with the variation of liver perfusion during pneumoperitoneum during laparoscopic surgery merits investigation.MethodsIn this prospective study, a total of sixty female patients scheduled for either selective laparoscopic gynaecological surgery (group laparoscopy) or laparotomy for gynaecological surgery (group control) were analyzed. Rocuronium was administered with closed-loop feedback infusion system, which was also applied to monitor NMB complied with good clinical research practice (GCRP). The onset time, clinical duration, and recovery index were measured. Hepatic blood flow was assessed by laparoscopic intraoperative ultrasonography before insufflation/after entering the abdominal cavity (T1), 5 min after insufflation in the Trendelenburg position/5 min after skin incision (T2), 15 min after insufflation in the Trendelenburg position/15 min after skin incision (T3), 30 min after insufflation in the Trendelenburg position/30 min after skin incision (T4), and 5 min after deflation/before closing the abdomen (T5) in group laparoscopy/group control respectively. The relationship between the clinical duration of rocuronium and portal venous blood flow was analyzed using linear or quadratic regression.ResultThe clinical duration and RI of rocuronium were both prolonged significantly in group laparoscopy (36.8 ± 8.3 min; 12.8 ± 5.5 min) compared to group control (29.0 ± 5.8 min; 9.8 ± 4.0 min) (P < 0.0001; P = 0.018). A significant decrease was found in portal venous blood flow during the entire pneumoperitoneum period in group laparoscopy compared with group control (P < 0.0001). There was a significant correlation between the clinical duration of rocuronium and portal venous blood flow (Y = 51.800-0.043X + (1.86E-005) X2; r2 = 0.491; P < 0.0001).ConclusionRocuronium-induced NMB during laparoscopic gynaecological surgery might be prolonged due to the decrease in portal venous blood flow induced by CO2-pneumoperitoneum. Less rocuronium could be required to achieve a desirable NMB in laparoscopic gynaecological surgery.Trial registrationChiCTR. Registry number: ChiCTR-OPN-15007524. Date of registration: December 4, 2015.

Laparoscopic partial nephrectomy (LPN) for totally intrarenal tumours

To evaluate the feasibility and outcomes of laparoscopic partial nephrectomy (LPN) for totally intrarenal tumours (TIT). TIT were defined as completely intraparenchymatic masses, without any exophytic element. Identification of such a tumour necessitates guidance of intraoperative laparoscopic ultrasonography. Data of patients with TIT who underwent LPN was collected from our Ethical Committee-approved database. Their data was compared with that of patients who underwent LPN for tumours with any degree of exophytic element. The two groups were compared for preoperative data (age, gender, tumour size and location), intraoperative variables (warm ischemia time [WIT], open conversions rate, radical nephrectomy [RN] rate, blood loss and other complications), and postoperative data (renal function, reoperation rates, pathological results, and incidence of positive surgical margins). Among 458 patients who underwent LPN, 41 had TIT. The mean (sd) tumour size was 2.6 (0.8) cm, mean WIT was 22.6 (13.8) min and blood loss was 279 (210) mL. The RN rate was significantly higher in the TIT group compared with the remaining cohort of LPNs (9.7% vs 5.3%). The intra- and postoperative complications, open conversion and positive margin rates were similar between the two groups. Malignant tumours were found in 84.2% and 78.2%, respectively. LPN for a TIT is technically feasible. TIT carry a significantly higher RN rate due to tumour involvement of vital kidney structures. This aspect should be discussed with the patient preoperatively but TIT should not be considered a definitive indication for RN.

Potential value of sonazoid-enhanced intraoperative laparoscopic ultrasonography for liver assessment during laparoscopy-assisted colectomy

PurposeLaparoscopy-assisted colectomy (LAC) has gained acceptance for the treatment of colorectal cancer. However, conventional palpation of the liver and adequate observation of the abdominal cavity are not achievable during LAC. The aim of this study was to assess the clinical value of using Sonazoid (contrast enhanced)-intraoperative laparoscopic ultrasonography (S-IOLUS) in patients with primary colorectal cancer.MethodsFrom May 2005 to August 2008, 454 patients underwent 339 LACs and 115 open colectomies for colorectal cancer. One hundred forty-eight patients with clinical stage II or III colorectal cancer, as determined by preoperative imaging, who were undergoing LACs were prospectively enrolled.ResultsAlthough IOLUS did not detect any lesions, small hypoechoic lesions were detected by the S-IOLUS (n = 71) in the Kupffer-phase view of two patients (2.8 %). None of the 71 patients who underwent S-IOLUS showed liver metastases within 6 months after LAC. In the conventional IOLUS group (n = 77), metastatic lesions were identified in two patients (2.6 %). The new liver metastases in these two patients were detected within 6 months after LAC.ConclusionsS-IOLUS of the liver during colorectal cancer surgery is useful for staging and as a diagnostic modality. It can identify lesions that are undetectable by preoperative imaging, and may be considered for routine use during LAC.

Comparison of laparoscopic and open intraoperative ultrasonography for staging liver tumours

Laparoscopic liver surgery must reproduce open surgical steps. Intraoperative ultrasonography (IOUS) is mandatory, but reliability of laparoscopic IOUS has been poorly evaluated. The aim of this study was to compare laparoscopic versus open IOUS in staging liver tumours. All patients scheduled for liver resection between September 2009 and March 2011 were considered. Inclusion criteria were primary and metastatic tumours. Exclusion criteria were: hilar/gallbladder cholangiocarcinoma, ten or more lesions, repeat resection, laparoscopic hepatectomy, adhesions and unresectability. Following percutaneous ultrasonography and thoracoabdominal computed tomography (CT), and on indication contrast-enhanced (CE) liver magnetic resonance imaging (MRI) and/or positron emission tomography (PET)-CT, patients were scheduled for laparoscopy, laparoscopic IOUS, then laparotomy, open IOUS and Partial hepatectomy. Data were collected prospectively. Reference standards were final pathology and 6-month follow-up results. Sixty-five patients were included, who had a median of 3 preoperative imaging studies (ultrasonography/CT 100 per cent, CE-MRI 67 per cent, PET-CT 54 per cent). A total of 119 lesions were diagnosed. Laparoscopic IOUS detected 22 additional lesions (+18·5 per cent) in 14 patients. Open IOUS detected two additional lesions, but did not confirm four lesions; overall 20 additional lesions (+16·8 per cent) were detected in ten patients. Pathology confirmed 14 newly detected malignant nodules (+11·8 per cent) in eight patients. After 6 months ten new nodules were identified in six patients. The sensitivity of preoperative imaging, laparoscopic IOUS and open IOUS was 83·1, 92·3 and 93·0 per cent respectively; accuracy was 79, 82 and 88 per cent. In comparison with open IOUS, the sensitivity and accuracy of laparoscopic IOUS were 98·6 and 94 per cent. Laparoscopic IOUS is a reliable tool for staging liver tumours with a performance similar to that of open IOUS in detecting new nodules.

Role of Laparoscopy in Changing the Management of Hepatocellular Carcinoma

Background: Laparoscopic approach offers the advantages of intra-operative laparoscopic ultrasonography (IOLUS), which provides better resolution of the number and location of liver tumors, and liver condition. In recent years the progress of laparoscopic procedures and the development of new and dedicated technologies have made laparoscopic hepatic surgery feasible and safe. The aim of this study is to present the results of our experience in laparoscopic management of Hepatocellular carcinoma (HCC) in cirrhotic patients. Patients and methods: Between September 2010 and January 2013, Four hundred patients with HCC in liver cirrhosis were referred from HCC clinic at National Hepatology and Tropical Medicine Research Institute (NHTMRI). 65 patients were submitted to diagnostic laparoscopy. 33 patients had Laparoscopic Radiofrequency Ablation with IOLUS guidance and 14 patients had laparoscopic non-anatomical resection while 18 patients had been converted to open laparotomy. Operation time, hospital stay, post-procedure complications were recorded. Spiral CT scan one month postoperative was mandatory during follow up. Results: Laparoscopic management was completed in 47 patients. The IOLUS examination identified new HCC in three patients. A total of 50 lesions were treated laparoscopically. The mean operative time was 120 ± 50 minutes; eight procedures were associated in six patients: cholecystectomy (6) and adhesiolysis (2). A complete tumor ablation was observed in treated patients by LRFA which were documented via spiral computed tomography (CT scan) one month after treatment. In resection group, histopathology was confirmed that, all tumor resection were with safety margin. Conclusion: Laparoscopic procedure proved to have a role in changing the management of HCC either by resection or by LRFA. Laparoscopy proved to be a safe and effective technique.

Robotic ultrasound probe for tumor identification in robotic partial nephrectomy: Initial series and outcomes

Accurate tumor identification during partial nephrectomy is essential for successful tumor control. Intraoperative laparoscopic ultrasonography is useful for tumor localization, but the ultrasound probe is controlled by the assistant rather than the surgeon. We evaluated our initial experience using a robotic ultrasound probe that is controlled by the console surgeon. Partial nephrectomy was carried out in 22 consecutive patients between November 2010 and March 2011. A robotic ultrasound probe under console surgeon control was used in all the cases. All patients had at least 1 year follow up. Mean patient age was 59 years and mean tumor size was 2.7 cm. There were six hilar tumors (27%) and 21 (95%) endophytic tumors. Mean R.E.N.A.L. nephrometry score was 6.9 (range 6-9). Mean operative time was 205.7 min and mean warm ischemia time was 17.9 min (range 6-28 min). All patients had negative tumor margins and were free of disease recurrence at a mean follow up of 13 months. The use of a robotic ultrasound probe during partial nephrectomy allows the surgeon to optimize tumor identification with maximal autonomy, and to benefit from the precision and articulation of the robotic instrument during this key step of the partial nephrectomy procedure.

Robot-assisted laparoscopic ultrasonography for hepatic surgery

This study describes and evaluates a novel, robot-assisted laparoscopic ultrasonographic device for hepatic surgery. Laparoscopic liver surgery is being performed with increasing frequency. One major drawback of this approach is the limited capability of intraoperative ultrasonography (IOUS) using standard laparoscopic devices. Robotic surgery systems offer the opportunity to develop new tools to improve techniques in minimally invasive surgery. This study evaluates a new integrated ultrasonography (US) device with the da Vinci Surgical System for laparoscopic visualization, comparing it with conventional handheld laparoscopic IOUS for performing key tasks in hepatic surgery. A prototype laparoscopic IOUS instrument was developed for the da Vinci Surgical System and compared with a conventional laparoscopic US device in simulation tasks: (1) Invivo porcine hepatic visualization and probe manipulation, (2) lesion detection accuracy, and (3) biopsy precision. Usability was queried by poststudy questionnaire. The robotic US proved better than conventional laparoscopic US in liver surface exploration (85% success vs 73%; P = .030) and tool manipulation (79% vs 57%; P = .028), whereas nodifference was detected in lesion identification (63 vs 58; P = .41) and needle biopsy tasks (57 vs 48; P = .11). Subjects found the robotic US to facilitate better probe positioning (80%), decrease fatigue (90%), and be more useful overall (90%) on the post-task questionnaire. We found this robot-assisted IOUS system to be practical and useful in the performance of important tasks required for hepatic surgery, outperforming free-hand laparoscopic IOUS for certain tasks, and was more subjectively usable to the surgeon. Systems such as this may expand the use of robotic surgery for complex operative procedures requiring IOUS.

Laparoscopic Ultrasound Enhances Diagnosis and Localization of Insulinoma in Pancreatic Head and Neck for Laparoscopic Surgery With Satisfactory Postsurgical Outcomes

This study explored the value of laparoscopic ultrasonography (LUS) for tumor localization in laparoscopic pancreatic surgery of insulinomas, especially for tumors located at anatomically unfavorable positions. Twenty-eight patients with insulinomas were enrolled in this study between July 2007 and March 2009. Various image examinations were performed preoperatively. An iU22 ultrasound system equipped with a 5.0–9.0 MHz transducer was used for LUS. The tumor localization and postsurgical outcomes were evaluated. Intraoperative LUS precisely localized 33 insulinomas in 26 of 28 patients, whereas the preoperative imaging studies detected 27 of 33 (82%) tumors. No definite tumor in the pancreas and extra-pancreatic organs was identified in two patients by both preoperative and intraoperative imaging examinations. Of 33 tumors, 32 (97%) were localized in the pancreas (14 in the head and neck, 18 in the body and tail), whereas one (3%) was found in the duodenal ligament. Successful laparoscopic resection of insulinoma was performed in 21 of 26 patients, including resection of 11 tumors located in the head and neck of the pancreas. Five patients required conversion to open surgery. All insulinomas were benign with a mean size 13.8 mm. Four patients had pancreatic-related complications that spontaneously healed within 3 weeks after surgery. The median hospital stay was 8.5 days. Our study demonstrates that laparoscopic pancreatic resection under the guidance of advanced LUS is not only feasible and safe for tumors located at the body and tail but also for tumors located at the head and neck of the pancreas.

Minimally Invasive Evaluation and Treatment of Colorectal Liver Metastases

Minimally invasive techniques used in the evaluation and treatment of colorectal liver metastases (CRLMs) include ultrasonography (US), computed tomography, magnetic resonance imaging, percutaneous and operative ablation therapy, standard laparoscopic techniques, robotic techniques, and experimental techniques of natural orifice endoscopic surgery. Laparoscopic techniques range from simple staging laparoscopy with or without laparoscopic intraoperative US, through intermediate techniques including simple liver resections (LRs), to advanced techniques such as major hepatectomies. Hereins, we review minimally invasive evaluation and treatment of CRLM, focusing on a comparison of open LR (OLR) and minimally invasive LR (MILR). Although there are no randomized trials comparing OLR and MILR, nonrandomized data suggest that MILR compares favorably with OLR regarding morbidity, mortality, LOS, and cost, although significant selection bias exists. The future of MILR will likely include expanding criteria for resectability of CRLM and should include both a patient registry and a formalized process for surgeon training and credentialing.

Intraoperative hydrocolonic ultrasonography for localization of small colorectal tumors in laparoscopic surgery

Accurate localization of small colorectal cancers and polyps during laparoscopic resection may be difficult and requires precise and reliable localization techniques. This study aimed to assess the usefulness of intraoperative ultrasonography (IOUS) combined with retrograde saline instillation in locating small colorectal cancers and polyps during laparoscopically assisted colectomy. The study investigated 14 patients with left-sided lesions of the colon and rectum necessitating preoperative marking. During laparoscopically assisted colorectal surgery, the large bowel was filled with saline solution by gravity, then scanned with a 5- to 10-MHz laparoscopic ultrasound probe. In all patients, both polyps and small cancers were clearly detected by IOUS. Furthermore, the technique was found to be easily mastered and performed. The mean detection time was 11 min. Polyps were seen as hypodense masses protruding from the bowel mucosa, whereas invasive cancers had both hypo- and hyperdense regions with sonographically appreciable penetration through bowel layers. Intraoperative laparoscopic ultrasonography in conjunction with saline instillation can serve as a useful tool that allows the surgeon to locate small nonpalpable tumors during laparoscopically assisted resection of colorectal cancer.

Hybrid Laparoscopic and Robotic Ultrasound-guided Radiofrequency Ablation-assisted Clampless Partial Nephrectomy

To describe a clampless approach made possible by creating an avascular plane of tissue with radiofrequency ablation. Laparoscopic partial nephrectomy is slowly gaining acceptance as a method to treat small (<4 cm) and select moderate (<7 cm) renal masses. The intricacies of laparoscopic suturing, which result in prolonged warm ischemia times, have delayed the widespread acceptance of this technique among urologists. Laparoscopic suturing to close the collecting system was done using the da Vinci robot. An avascular plane of tissue from coagulation necrosis was achieved with the Habib 4X radiofrequency ablation device and the Rita 1500X generator. Typically, we used a power setting of 50 W but have found settings as low as 25 W necessary to provide hemostasis for larger vessels. The tumor was then sharply excised with a negative margin using robotic scissors and electrocautery to facilitate tissue cutting. Retrograde injection of methylthioninium chloride and saline through an externalized ureteral catheter allowed for precise sutured closure of the collecting system. FloSeal and BioGlue were then applied, making surgical bolsters or parenchymal sutures unnecessary. Intraoperative histologic evaluation of the surgical margin and repeat resection of the tumor bed was possible because the renal hilum was not clamped, and no warm ischemia was used. This technique, which combines the improving technologies of robotic surgery, intraoperative laparoscopic ultrasonography, and radiofrequency ablation, might make more surgeons comfortable with the intricacies of laparoscopic suturing and eliminate prolonged warm ischemia times. Overall, this method should result in more patients being able to undergo minimally invasive laparoscopic partial nephrectomy.