Experience with ultrasound scissors and blades (UltraCision) in open and laparoscopic liver resection

The CUSA Clarity Soft Tissue Removal Study: Clinical Performance Investigation of the CUSA Clarity Ultrasonic Surgical Aspirator System for Soft Tissue Removal During Liver Surgery

Background: Intraoperative blood loss has an unfavorable impact on the outcome of patients undergoing liver surgery. Today, the use of devices capable of minimizing this risk with high technical performance becomes mandatory. Into this scenario fits the CUSA® Clarity Ultrasonic Surgical Aspirator System. This prospective survey involving five liver surgery centers had the objective of investigating whether this innovative ultrasonic surgical aspirator is safe and effective in the transection of the liver parenchyma. Materials and Methods: This clinical study was a prospective, multicenter, single-arm Post-Market Clinical Follow-up study investigating 100 subjects who underwent liver surgery using the CUSA Clarity Ultrasonic Surgical Aspirator System at five centers during a period of 1 year and 8 months. After collecting all the patient's clinical information and instrument usage details, surgeons completed a brief survey giving their opinions on the performance of CUSA. Therefore, safety and efficacy outcomes were evaluated. Results: Surgeons had a 95% success rate in complete removal of the mass with an average overall operative time of 4 hours and 34 minutes. Overall, there were no complications or device deficiencies. Conclusion: The CUSA Clarity Ultrasonic Surgical Aspirator System performs well during liver surgery with a low complication rate. ClinicalTrials.gov Identifier: NCT04298268.

Laparoscopic liver resection with "ultrasonic scalpel mimic CUSA" technique

BACKGROUND

Liver parenchymal transection is the most critical step for laparoscopic liver resection (LLR). Ultrasonic scalpel (Harmonic) is a common used energy instrument in LLR; however, it is only recommended for superficial layer transection and the Cavitron Ultrasonic Surgical Aspirator (CUSA) is recommended for deep layer dissection. We herein introduce the "Harmonic mimic CUSA" technique for LLR.

METHODS

We retrospectively reviewed the medical records of the patients who underwent LLR using CUSA or the "Harmonic mimic CUSA" for parenchymal transection between July 2018 and October 2020 at West China Hospital of Sichuan University. Observation indicators included general demographic information, operative time, intraoperative blood loss, blood transfusion volume, complication rate, hospital stay, and the costs. Perioperative data was compared between the two groups by propensity score matching analysis (PSM).

RESULTS

A total of 298 patients, including 192 in Harmonic group and 106 in CUSA group, were enrolled in this study. After a 1:1 PSM, 99 patients using "Harmonic mimic CUSA" were matched with 99 patients via CUSA for parenchymal transection in LLRs. The Harmonic group had significantly less intraoperative blood loss (mean, 150 ml vs. 250 ml, P < 0.001), shorter operative time (mean 170 min vs. 250 min, P < 0.001) and less costs (mean 6723$ vs. 8307$, P < 0.001). The conversion to laparotomy, length of postoperative hospital stay, complications were comparable between the two groups. There perioperative mortality was nil.

CONCLUSION

The "Harmonic mimic CUSA" technique is safe, simple and feasible for LLR, which may be an alternative to CUSA for LLR.

A Novel Technique Using Ultrasonic Shears Versus Traditional Methods of Reduction of Bilateral Labia Minora Hypertrophy: A Retrospective Case-Control Study

INTRODUCTION

To compare the clinical outcomes of bilateral labia minora hypertrophy reduction using ultrasonic shears versus traditional methods.

MATERIALS AND METHODS

In this retrospective study, we evaluate the surgical outcomes of 11 women who underwent bilateral labia minora hypertrophy reduction using ultrasonic shears to 14 women who underwent the same procedure using various traditional methods between January 1, 2015 and February 29, 2020 in a single center. The primary outcomes evaluated are total operative time, estimated blood loss, and postoperative pain. Secondary outcomes include postoperative complications and total admission time. The statistical analyses used were exact Wilconxon Rank and Fisher's exact test.

RESULTS

25 total bilateral labiaplasty procedures were included in the analysis. 11 procedures were performed using ultrasonic shears and 14 were performed using traditional methods. The mean reduction operative time for the ultrasonic shears technique when compared with traditional methods was 43.25 minutes (22.82 minutes versus 66.07 minutes, P = .0002). A statistically significant but non-clinically significant difference in estimated blood loss was noted. No statistically significant differences existed with postoperative pain score, total admission time, or postoperative complications.

CONCLUSIONS

Ultrasonic shears significantly reduce the time needed for the reduction of bilateral labia minora hypertrophy and therefore should be considered by surgeons as a useful tool in increasing the efficiency of this procedure.

The use of Thulium-Doped Fiber Laser (TDFL) 1940 nm as an energy device in liver parenchyma resection, a-pilot-study in Indonesia

Introduction

Several modalities are used to improve the outcome of liver resection surgery. Laser-based surgery may become promising option; therefore we aim to report our experience regarding the efficacy and safety of Thulium-Doped Fiber Laser (TDFL) 1940 nm in liver parenchyma resection.

Methods

A cross sectional study in which patients with pre-existing liver pathology during July 2019 and July 2020 were randomly assigned to receive liver resection using TDFL integrated with raman laser emitting at 1940 nm and 1470 nm wavelength. Data on estimated blood loss during liver transection, liver transection speed, morbidity rate, and postoperative variables including complications, length of hospital stay (days), and mortality were analyzed.

Results

A total of 17 consecutive liver resections were performed, among them are 7 major and 11 minor hepatectomies. The Multipulse TM+1470 were used on 8 procedures consisted of 1 major and 7 minor hepatectomies, the mean amount of blood loss during operation and liver transection was 628.13 ± 141.31 mL and 294.63 ± 94.81 ml, respectively. The mean liver transection speed was 1.52 ± 0.27 cm²/min. No biliary leak, post-hepatectomy-liver failure, and mortality were reported.

Conclusion

TDFL provided by Multipulse TM+1470 is an effective and safe tool for liver surgery, providing good hemostasis and allowing for safe and effective exposure of vascular. Further study with larger samples might be needed proved the efficacy and safety of TDFL in liver surgery.

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Despite promising laser device features, the usage in liver surgery is still rare.

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TDFL provides precision transection and good hemostasis.

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Low intraoperative blood loss is observed in TDFL liver surgery.

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No bile leak and post hepatectomy liver failure was observed after TDFL surgery.

Clamp-Crush Technique Versus Harmonic Scalpel for Hepatic Parenchymal Transection in Living Donor Hepatectomy: a Randomized Controlled Trial

BACKGROUND

Hepatic parenchymal transection is the most invasive step in donor operation. During this step, blood loss and unintended injuries to the intrahepatic structures and hepatic remnant may occur. There is no evidence to prove the ideal techniques for hepatic parenchymal transection. The aim of this study is to compare the safety, efficacy, and outcome of clamp-crush technique versus harmonic scalpel as a method of parenchymal transection in living-donor hepatectomy.

METHODS

Consecutive living liver donors, undergoing right hemi-hepatectomy, during the period between May 2015 and April 2016, were included in this prospective randomized study. Cases were randomized into two groups; group (A) harmonic scalpel group and group (B) Clamp-crush group.

RESULTS

During the study period, 72 cases underwent right hemi-hepatectomy for adult living donor liver transplantation and were randomized into two groups. There were no statistically significant differences between the two groups regarding preoperative demographic and radiological data. Longer operation time and hepatectomy duration were found in group B. There were no significant differences between the two groups regarding blood loss, blood loss during hepatectomy, and blood transfusion. More unexpected bleeding events occurred in group A. Higher necrosis at the cut margin of the liver parenchyma was noted in group A. There were no statistically significant differences between the two groups regarding postoperative ICU stay, hospital stay, postoperative morbidities, and readmission rates.

CONCLUSION

Clamp-crush technique is advocated as a simple, easy, safe, and cheaper method for hepatic parenchymal transection in living donors.

Feasibility Study of a Newly Developed Hybrid Energy Device Used During Laparoscopic Liver Resection in a Porcine Model

BACKGROUND

Although various devices have been clinically used for laparoscopic liver resection (LLR), the best device for liver parenchymal transection remains unknown. Olympus Corp (Tokyo, Japan) developed a laparoscopic hybrid pencil (LHP) device, which is the first electric knife to combine ultrasound and electric energy with a monopolar output. We aimed to evaluate the feasibility of using the LHP device and to compare it with the laparoscopic monopolar pencil (LMP) and laparoscopic ultrasonic shears (LUS) devices for LLR in a porcine model.

METHODS

Nine male piglets underwent laparoscopic liver lobe transections using each device. The operative parameters were evaluated in the 3 groups (n = 24 lobes) during the acute study period. The imaging findings from contrast-enhanced computed tomography and histopathological findings of autopsy on postoperative day 7 were compared among groups (n = 6 piglets) during the long-term study.

RESULTS

The transection time was shorter ( P = .001); there was less blood loss ( P = .018); and tip cleaning ( P < .001) and instrument changes were less often required ( P < .001) in the LHP group than in the LMP group. The LHP group had fewer instances of bleeding ( P < .001) and coagulator usage ( P < .001) than did the LUS group. In the long-term study, no postoperative adverse events occurred in the 3 groups. The thermal spread and depth of the LHP device were equivalent to those of the LMP and LUS devices (vs LMP: P = .226 and .159; vs LUS: P = 1.000 and .574).

CONCLUSIONS

The LHP device may be an efficient device for LLR if it can be applied to human surgery.

Precise Navigation of the Surgical Plane with Intraoperative Real-time Virtual Sonography and 3D Simulation in Liver Resection

The precise intraoperative navigation of the surgical plane remains challenging in liver surgery; however, an innovative imaging technique-real-time virtual sonography (RVS)-may provide a solution. In this modality, preoperative three-dimensional (3D) resection simulation data are transmitted to an RVS workstation and can be used in combination with intraoperative ultrasound to navigate the surgical plane in real time. This paper describes this technique and our experiences in detail. From November 2015 to March 2017, 26 patients with primary liver cancer underwent liver resection under RVS navigation. The operative procedures employed included hemihepatectomy, bisegmentectomy, segmentectomy, and limited resection. RVS was utilized uneventfully and successfully in each operation. The median time required for spatial position registration was 3 (1-12) min, and as the case volume increased, the time required for registration markedly decreased. The surgical plane under RVS navigation was consistent with that of the preoperative plan, and the resection margin was confirmed negative in each case. In conclusion, RVS in combination with 3D simulation is a feasible, safe, and promising technique for the precise intraoperative navigation of liver resection for primary liver cancer. It could be applied to other resectable liver diseases and may be utilized in other centers.

Use of ultrasonic scalpel and monopolar electrocautery for skin incisions in neck dissection: a prospective randomized trial

PURPOSE

Ultrasonic scalpel (UC) and monopolar electrocautery (ME) are standard equipment for soft tissue surgery. The aim of the present study was to compare intraoperative and postoperative patterns of patients using either UC or ME for skin incisions in neck dissection.

MATERIAL AND METHODS

In a prospective randomized study of 30 patients, the thermal effects of UC (n = 15) and ME (n = 15) were examined using real-time infrared thermographic imaging. Additionally, tissue damage was evaluated histopathologically. The other measured variables were operation and bleeding time, postoperative pain score (only neck incision area), in-patient time, and complications.

RESULTS

UC significantly reduces the thermal effects, compared to ME (p < 0.001). The mean depth of tissue damage (i.e., necrosis) was 272.7 μm for UC and 284.7 μm for ME with no significant difference (p = 0.285). From the third postoperative day, patients treated using UC had noticeably less pain in the neck incision area (t3 p = 0.010; t4 p < 0.001; t5 p < 0.005). Cutting time was reduced for ME by 36.1 s (p < 0.001) and the bleeding time was decreased by 40.9 s for UC (p < 0.001). The total preparation time was the same (p = 0.402). When comparing in-patient time (p = 0.723), as well as complications, no significant differences were seen.

CONCLUSION

UC results in less postoperative pain and less bleeding in the neck incision area. Accordingly, UC is superior to ME for skin incisions in neck dissection.

Comparative Study With Propensity Score Matching Analysis of Two Different Methods of Transection During Hemi-Right Hepatectomy: Ultracision Harmonic Scalpel Versus Cavitron Ultrasonic Surgical Aspirator

BACKGROUND

Several devices are available for liver parenchyma transection (LPT). The aim of this study was to compare the Ultracision Harmonic scalpel (UHS) with the Cavitron Ultrasonic Surgical Aspirator (CUSA) among patients who underwent hemi-right hepatectomies (RH) to homogenize transection areas.

METHODS

From September 2012 to June 2015, 24 patients who underwent the UHS surgery approach were matched with 24 patients who underwent the CUSA transection procedure for RH using propensity score matching.

RESULTS

Total operative time (TOT) was shorter in the UHS group, 240 minutes (range 172.5-298.8) versus 330 minutes (range 270-400) in the CUSA group ( P = .0002). The occurrence of hepatopathy (odds ratio = 17; 95% confidence interval = 1.02-230) and the use of the CUSA device (odds ratio = 8; 95% confidence interval = 0.98-77) were associated with a TOT exceeding 300 minutes in multivariate analysis ( P = .05).

CONCLUSIONS

The UHS is a safe and effective method of LPT as compared to the use of the CUSA system. TOT is statistically decreased.

[Liver transection: modern procedure: Technique, results and costs]

Liver resection has developed into the current standard procedure due to modern resection techniques, profound knowledge of the liver anatomy and optimized surgical and anesthesiological strategies to allow extended resections with both low morbidity and mortality. Initially major blood loss was the biggest concern with liver resection and a Pringle's manoeuvre was necessary. Nowadays, biliary leakage is the major problem after liver surgery. Besides the classical conventional clamp crushing technique for parenchymal transection, various devices including ultrasound, microwaves and staplers have been introduced. Minimally invasive techniques have become increasingly important for liver resection but are still applied in selected patients only. The selection of the resection technique and device mainly depends on the extent of the resection and also on the liver parenchyma, the liver disease, costs, personal experiences and preferences. This article presents a selection of techniques used in modern parenchymal transection during liver resection with special focus on transection time, blood loss, bile leakage and costs.

Ultrasonic Dissection versus Conventional Dissection for Pancreatic Surgery: A Meta-Analysis

Background. The role of ultrasonic dissection (UD) in pancreatic surgery remains controversial. The aim of this meta-analysis was to evaluate the clinical effect of UD in pancreatic surgery when compared with conventional dissection (CD). Materials and Methods. A comprehensive literature search was performed to identify eligible studies that compared UD with CD for pancreatic surgery in PubMed, EMBASE, Web of Science, and the Cochrane Library. Risk ratio (RR) or mean difference with 95% confidence interval (CI) was calculated. Results. Six studies were included with a total of 215 patients undergoing UD and 210 undergoing CD. In comparison with CD in distal pancreatectomy, UD was associated with lower rates of pancreatic fistula (RR = 0.46, 95% CI: 0.27–0.76) and abdominal abscess and shorter operation time and hospital stay (P < 0.05). In pancreaticoduodenectomy, there was no significant difference in pancreatic fistula rate between two groups (RR = 0.79, 95% CI: 0.48–1.29). However, the significantly less intraoperative blood loss and the transfused blood unit were found in patients receiving UD (P < 0.05). Conclusions. The results of this meta-analysis show that, in comparison with CD, UD is associated with better perioperative outcomes in pancreatic surgery.

High-power characterization of a microcutter actuated by PMN-PT piezocrystals

An ultrasonic microcutter is an alternative approach to conventional ultrasonic instruments actuated by sandwich piezoelectric transducers for surgery. This paper reports high-power behavior of a microcutter actuated by the piezocrystal lead magnesium niobate-lead titanate (PMN-PT), defining its practical performance and the feasibility of PMNPT actuation for surgical applications. The microcutter was driven at resonance with constant current amplitudes, either unloaded or loaded by poultry breast tissue, until its behavior achieved a steady state. During this driving process, its electric impedance, resonant frequency, and vibration velocity, along with the temperature increase of the PMN-PT, were recorded in real time. The microcutter produced a maximum vibration velocity >2.8 m/s with an excitation current of 0.11 A(rms). The mechanical loss increased significantly with current amplitude, resulting in a maximum temperature increase approaching 50°C around the interface between the PMN-PT and the blade, where they were bonded together with epoxy. Because of the low phase-transition temperature of PMN-PT, this temperature rise prevented the microcutter from working at higher current amplitudes. Along with the high vibration velocity, it also caused a frequency shift downward by 3 kHz at the same current amplitude. During tests with poultry breast tissue, radiation reactance increased the resonant frequency and the radiation resistance increased the loss of the microcutter. However, the loss did not further increase the temperature of the piezoelectric material. The maximum force and the overall work required to penetrate the microcutter into poultry breast tissue were reduced by 47.1 ± 8% and 53.5 ± 6%, respectively, when the microcutter was actuated at a current of 0.07 A(rms).

Simultaneous Laparoscopy-Assisted Resection for Colorectal Cancer and Metastases

With advancement of minimal invasive surgery, a simultaneous laparoscopy-assisted resection for colorectal cancer and metastasis has become feasible. Hence, we report three cases of simultaneous laparoscopic surgery for colorectal cancer with liver or lung metastasis. In the first case, laparoscopic right hemicolectomy and left lateral segmentectomy of liver was performed for ascending colon cancer and liver metastasis. In the second case, laparoscopic right hemicolectomy and wedge resection of right lower lung was performed for cecal cancer and lung metastasis. In the third case, laparoscopic right hemicolectomy and wedge resection of left lower lung was performed for ascending colon cancer and lung metastasis. In the first two cases, patients quickly returned to normal activity. In the third case, postoperative bleeding was observed, but spontaneously stopped. There was no postoperative mortality. Simultaneous laparoscopic surgery represents a feasible option for colorectal cancer with metastases on the other organs.

What is the best technique in parenchymal transection in laparoscopic liver resection? Comprehensive review for the clinical question on the 2nd International Consensus Conference on Laparoscopic Liver Resection

The continuing evolution of technique and devices used in laparoscopic liver resection (LLR) has allowed successful application of this minimally invasive surgery for the treatment of liver disease. However, the type of instruments by energy sources and technique used vary among each institution. We reviewed the literature to seek the best technique for parenchymal transection, which was proposed as one of the important clinical question in the 2nd International Consensus Conference on LLR held on October 2014. While publications have described transection techniques used in LLR from 1991 to June 2014, it is difficult to specify the best technique and device for laparoscopic hepatic parenchymal transection, owing to a lack of randomized trials with only a small number of comparative studies. However, it is clear that instruments should be used in combination with others based on their functions and the depth of liver resection. Most authors have reported using staplers to secure and divide major vessels. Preparation for prevention of unexpected hemorrhaging particularly in liver cirrhosis, the Pringle's maneuver and prompt technique for hemostasis should be performed. We conclude that hepatobiliary surgeons should select techniques based on their familiarity with a concrete understanding of instruments and individualize to the procedure of LLR.

Modern technical approaches in resectional hepatic surgery

Techniques in liver surgery have improved considerably during the last decades, allowing for liver resections with low morbidity and mortality. Preoperative patient selection, perioperative management, and intraoperative blood-sparing techniques are the cornerstones of modern liver surgery. Multimodal treatment of colorectal liver metastases has expanded the group of patients who are potential candidates for liver resection. Adjunctive techniques, including preoperative portal vein embolization and staged hepatectomy, have facilitated the safe performance of extensive liver resection. This article provides an overview of indications for liver resection and a systematic description of the technical approach to the most commonly performed resections.

Sealing vessels up to 7 mm in diameter solely with ultrasonic technology

Introduction

Ultrasonic energy is a mainstay in the armamentarium of surgeons, providing multifunctionality, precision, and control when dissecting and sealing vessels up to 5 mm in diameter. Historically, the inability to seal vessels in the 5–7 mm range has been perceived as an inherent limitation of ultrasonic technology. The purpose of this study was to evaluate sealing of vessels up to 7 mm in diameter with an ultrasonic device that modulates energy delivery during the sealing period.

Methods

In ex vivo benchtop and in vivo acute and survival preclinical models, a new ultrasonic device, Harmonic ACE^®+7 Shears (Harmonic 7), was compared with advanced bipolar devices in sealing vessels 1–7 mm in diameter with respect of burst pressure, seal reliability, and seal durability. Lateral thermal damage and transection time were also evaluated.

Results

Ex vivo tests of Harmonic 7 demonstrated significantly greater median burst pressures than an advanced bipolar device both for vessels <5 mm in diameter (1,078 mmHg and 836 mmHg, respectively, P=0.046) and for those in the range of 5–7 mm (1,419 mmHg and 591 mmHg, P<0.001). In vivo tests in porcine and caprine models demonstrated similar rates of hemostasis between Harmonic 7 and advanced bipolar devices, with high success rates at initial transection and seal durability of 100% after a 30-day survival period.

Conclusion

Sealing 5–7 mm vessels is not a limitation of the type of energy used but of how energy is delivered to tissue. These studies document the ability of ultrasonic energy alone to reliably seal large vessels 5–7 mm in diameter, with significantly greater burst pressure observed in in vitro studies than those observed with an advanced bipolar technology when energy delivery is modulated during the sealing cycle. Furthermore, the seals created in 5–7 mm vessels are shown to be reliable and durable in in vivo preclinical studies.

Tissue effects in vessel sealing and transection from an ultrasonic device with more intelligent control of energy delivery

BACKGROUND

Ultrasonic surgical devices have been demonstrated to provide excellent hemostasis, efficient transection, minimal lateral thermal damage, low smoke generation, and no risk of electrical current passage to the patient. These benefits originate from the inherent characteristics of the ultrasonic mechanism, but further improvements were thought possible through optimization of the energy delivery during application. The study reported here compared a new ultrasonic device, Harmonic ACE®+ Shears with Adaptive Tissue Technology, with a commercial predicate device, Harmonic ACE® Shears (both Ethicon Endo-Surgery, Inc., Cincinnati, OH, USA).

METHODS

Devices were evaluated in an in vivo porcine model intraoperatively and after a 30-day survival period. Both devices were used to seal a variety of vessels 1-5 mm in diameter, and compared for hemostasis, histological thermal damage, and adhesion formation. Sealed vessels were evaluated ex vivo for burst pressure, and visual obstruction caused by plumage from device application was assessed quantitatively.

RESULTS

ACE+ produced significantly less thermal damage, had fewer adhesions, offered faster transection, involved less visual obstruction, and had higher burst pressures than the predicate device. All vessel seals, evaluated over the course of a 30-day survival period in pigs, remained intact.

CONCLUSION

The new Adaptive Tissue Technology algorithm assists the surgeon in achieving better control of energy delivery to the tissue, sealing vessels with supra-physiological burst pressures, and low thermal damage. These preclinical results with Harmonic ACE+ may translate into meaningful clinical benefits, providing greater precision along with more efficient and effective cutting and coagulation in open or laparoscopic procedures.

Comparative analysis of different transection techniques in minor and major hepatic resections: a prospective cohort study

BACKGROUND

In liver surgery different transection techniques are available without clear evidence regarding indication and advantage for each technique. The aim of this study was to identify the most superior liver transection technique between the different techniques (stapler, water-jet and electrocautery). Comparative analyses were performed for minor and major hepatectomies.

METHODS

In a single-center study, all liver resections performed between July 2007 and July 2012 were prospectively recorded and analysed.

RESULTS

366 liver resections were included according to predefined eligibility criteria. No clear benefit for one particular technique in minor or major hepatectomy could be shown. Cost-effectiveness analysis revealed disadvantages for stapler-hepatectomies. However, minor hepatectomies were performed with significantly lower morbidity (p < 0.001), lower operating time (p = 0.001), fewer need of transfusion (p < 0.0001) and shorter ICU stay (p = 0.001) than major hepatectomies.

CONCLUSIONS

If possible, minor hepatectomies should be chosen. Competing techniques, selected according to surgeon's preference, revealed no significant differences in primary outcome measures.

Variations of bubble cavitation and temperature elevation during lesion formation by high-intensity focused ultrasound

High-intensity focused ultrasound (HIFU) is emerging as an effective therapeutic modality in both thermal ablations for solid tumor/cancer and soft-tissue fragmentation. Mechanical and thermal effects, which play an important role in the HIFU treatment simultaneously, are dependent on the operating parameters and may vary with the progress of therapy. Mechanical erosion in the shape of a "squid," a "dumbbell" lesion with both mechanical and thermal lesions, or a "tadpole" lesion with mechanical erosion at the center and thermal necrosis on the boundary in the transparent gel phantom could be produced correspondingly with the pulse duration of 5-30 ms, which is much longer than histotripsy burst but shorter than the time for tissue boiling, and pulse repetition frequency (PRF) of 0.2-5 Hz. Meanwhile, variations of bubble cavitation (both inertial and stable cavitation) and temperature elevation in the focal region (i.e., z = -2.5, 0, and 2.5 mm) were measured by passive cavitation detection (PCD) and thermocouples during the therapeutic procedure, respectively. Stable cavitation increased with the pulse duration, PRF, and the number of pulses delivered. However, inertial cavitation was found to increase initially and then decrease with long pulse duration and high PRF. Temperature in the pre-focal region is always higher than those at the focal and post-focal position in all tests. Great variations of PCD signals and temperature elevation are due to the generation and persistence of large bubble, which is resistant to collapse and occurs with the increase of pulse duration and PRF. Similar lesion pattern and variations were also observed in ex vivo porcine kidneys. Hyperechoes in the B-mode ultrasound image were comparable to the shape and size of lesions in the dissected tissue. Thermal lesion volume increased with the increase of pulse duration and PRF, but mechanical erosion reached its maximum volume with the pulse duration of 20 ms and PRF of 1 Hz. Altogether, bubble cavitation and thermal field vary with the progress of HIFU treatment with different sonication parameters, which provide insights into the interaction of ultrasound burst with the induced bubbles for both soft tissue fractionation and enhancement in thermal accumulation. Appropriate synergy and monitoring of mechanical and thermal effects would broaden the HIFU application and enhance its efficiency as well as safety.

[Suture materials in urology]

Since ancient times, sutures have been a fundamental part of the surgeon's practice. Beside the vegetable and animal origin materials, in the last decades different refined synthetic materials have been introduced in the clinical practice. More recently, different devices, such as staplers and tissue sealers have been developed. Thus, more than ever, urologists are faced with a multitude of suture materials, and research of safe, effective materials and devices seems to be continuously growing. The introduction and widespread diffusion of laparoscopic and robotic surgery has further boosted this research. Given there is no single material that is ideal for all situations, the surgeon must choose the best material for each particular case.
The aim of this non-systematic review is to summarize the more innovative suture materials and devices and to describe the different surgical methods to utilize them both in general and in urologic surgery.

Ultrasonic dissection versus conventional dissection techniques in pancreatic surgery: a randomized multicentre study

OBJECTIVE

: This prospective randomized multicenter trial was performed to assess the potential benefits of ultrasonic energy dissection compared with conventional dissection techniques in pancreatic surgery.

BACKGROUND

: Surgical procedures for tumors of the pancreatic head involve time-consuming manual dissection. The primary hypothesis was that use of ultrasonic tissue and vessel dissection would lead to substantial saving in operative time during pancreatic resection.

METHODS

: Patients eligible for pancreaticoduodenectomy (PD) or pylorus-preserving PD (PPPD) were randomized to group A (dissection with ultrasonic device) or group B (conventional dissection) from March 2009 to May 2011. The primary endpoint was overall duration of operation time. Secondary endpoints were time to end of resection phase, intraoperative blood loss, number of transfused units of blood, and postoperative morbidity.

RESULTS

: Analysis of primary and secondary endpoints included 101 patients, who received either PD or PPPD. Demographical characteristics and clinical parameters were similar in both groups. The use of an ultrasonic dissection device did not significantly reduce overall operation time (median 316 minutes in group A and 319 minutes in group B, P = 0.95) and did not significantly increase the costs of surgery. Analysis of secondary endpoints revealed no difference in postoperative course.

CONCLUSIONS

: Tissue dissection and vessel closure using an ultrasonic device is equivalent to dissection with conventional techniques in pancreatic surgery.

Comparison of liver parenchymal ablation and tissue necrosis in a cadaveric bovine model using the Harmonic Scalpel, the LigaSure, the Cavitron Ultrasonic Surgical Aspirator and the Aquamantys devices

OBJECTIVES

The amount of tissue that is ablated or necrosed at the line of parenchymal transection is of clinical significance in the interpretation of resection margin status following hepatic resection. The aim of this study was to define the extent of parenchymal ablation and necrosis in liver tissue using the Harmonic Scalpel, the LigaSure, the Cavitron Ultrasonic Surgical Aspirator (CUSA) and the Aquamantys dissector ex vivo.

METHODS

Mounted blocks of non-perfused bovine liver were transected using the Harmonic Scalpel, LigaSure, CUSA and Aquamantys devices. Outcome measures included parenchymal ablation (ablation band widths and weights) and tissue necrosis band widths along the line of transection. Each experiment was replicated five times.

RESULTS

All devices were associated with parenchymal ablation (Harmonic Scalpel, 4.73 ± 1.62 mm; LigaSure, 4.55 ± 2.02 mm; CUSA, 7.16 ± 2.87 mm; Aquamantys, 4.75 ± 1.43 mm) and tissue necrosis (Harmonic Scalpel, 1.07 ± 0.46 mm; LigaSure, 1.36 ± 0.36 mm; CUSA, 0.81 ± 0.21 mm; Aquamantys, 0.81 ± 0.36 mm).

CONCLUSIONS

The Harmonic Scalpel, LigaSure, CUSA and Aquamantys devices were associated with bands of tissue loss along the hepatic parenchymal transection line in this benchtop cadaveric model. This should be taken into account in the interpretation of resection margin status following liver resection.

Bleeding in Hepatic Surgery: Sorting through Methods to Prevent It

Liver resections are demanding operations which can have life threatening complications although they are performed by experienced liver surgeons. The parameter “Blood Loss” has a central role in liver surgery, and different strategies to minimize it are a key to improve results. Moreover, recently, new technologies are applied in the field of liver surgery, having one goal: safer and easier liver operations. The aim of this paper is to review the different principal solutions to the problem of blood loss in hepatic surgery, focusing on technical aspects of new devices.

Is ultracision knife safe and efficient for breast capsulectomy? A preliminary study

BACKGROUND

Silicone breast implants are used to a wide extent in the field of plastic surgery. However, capsular contracture remains a considerable concern. This study aimed to analyze the effectiveness and applicability of an ultracision knife for capsulectomy breast surgery.

METHODS

A prospective, single-center, randomized study was performed in 2009. The inclusion criteria specified female patients 20-80 years of age with capsular contracture (Baker 3-4). Ventral capsulectomy was performed using an ultracision knife on one side and the conventional Metzenbaum-type scissors and surgical knife on the collateral side of the breast. Measurements of the resected capsular ventral fragment, operative time, remaining breast tissue, drainage time, seroma and hematoma formation, visual analog scale pain score, and sensory function of the nipple-areola complex were assessed. In addition, histologic analysis of the resected capsule was performed.

RESULTS

Five patients (median age, 59.2 years) were included in this study with a mean follow-up period of 6 months. Three patients had Baker grade 3 capsular contracture, and two patients had Baker grade 4 capsular contracture. The ultracision knife was associated with a significantly lower pain score, shorter operative time, smaller drainage volume, and shorter drainage time and resulted in a larger amount of remaining breast tissue. Histologic analysis of the resected capsule showed no apoptotic cells in the study group or control group.

CONCLUSIONS

The results suggest that ventral capsulectomy with Baker grade 3 or 4 contracture using the ultracision knife is feasible, safe, and more efficient than blunt dissection and monopolar cutting diathermy and has a short learning curve.

LEVEL OF EVIDENCE II

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors at www.springer.com/00266.

Ultrasonic scalpel causes greater depth of soft tissue necrosis compared to monopolar electrocautery at standard power level settings in a pig model

Background

Ultrasonic scalpel (UC) and monopolar electrocautery (ME) are common tools for soft tissue dissection. However, morphological data on the related tissue alteration are discordant. We developed an automatic device for standardized sample excision and compared quality and depth of morphological changes caused by UC and ME in a pig model.

Methods

100 tissue samples (5 × 3 cm) of the abdominal wall were excised in 16 pigs. Excisions were randomly performed manually or by using the self-constructed automatic device at standard power levels (60 W cutting in ME, level 5 in UC) for abdominal surgery. Quality of tissue alteration and depth of coagulation necrosis were examined histopathologically. Device (UC vs. ME) and mode (manually vs. automatic) effects were studied by two-way analysis of variance at a significance level of 5%.

Results

At the investigated power level settings UC and ME induced qualitatively similar coagulation necroses. Mean depth of necrosis was 450.4 ± 457.8 μm for manual UC and 553.5 ± 326.9 μm for automatic UC versus 149.0 ± 74.3 μm for manual ME and 257.6 ± 119.4 μm for automatic ME. Coagulation necrosis was significantly deeper (p < 0.01) when UC was used compared to ME. The mode of excision (manual versus automatic) did not influence the depth of necrosis (p = 0.85). There was no significant interaction between dissection tool and mode of excision (p = 0.93).

Conclusions

Thermal injury caused by UC and ME results in qualitatively similar coagulation necrosis. The depth of necrosis is significantly greater in UC compared to ME at investigated standard power levels.

Tissue damage with different surgical techniques in a porcine model of liver resection: implications for living-donor liver transplantation?

Background/purpose

For living-donor liver transplantation (LDLT) it is of paramount importance to preserve as much viable liver tissue as possible to avoid postoperative complications in the donor and recipient. The depth of tissue damage caused by common surgical techniques for liver resection has not been studied so far.

Methods

Here we compared the depth of tissue damage and the immunohistochemical expression of heat shock protein (HSP) 70, a marker for tissue damage, in a porcine model of liver resection, to assess the effect of different surgical techniques, i.e., blunt dissection (BD), and dissection with an ultrasound aspirator (UA), an ultrasound scalpel (US), or a water-jet (WJ).

Results

Analysis with linear mixed effects models (LME) showed significantly less tissue damage with BD and UA than with US and WJ (joint p value <0.001). Damage also increased within 6 h after surgery (p value = 0.004). Semiquantitative evaluation of HSP 70 showed increased expression after resection with US compared to all other resection methods (p value <0.001), indicating increased tissue damage with this method.

Conclusion

We suggest that in cases of liver resection for LDLT surgeons should reevaluate using US and WJ because of possible excessive tissue damage compared to BD and UA. Overall we advocate the use of BD as it requires no special equipment and, hence, has considerably higher cost-effectiveness without compromising tissue preservation and clinical outcome and is readily available even in low-tech environments.

Milestones in the evolution of hepatic surgery

This paper describes the rapid evolution of modern liver surgery, starting in the middle of the twentieth century. Claude Couinaud studied and described the segmental anatomy of the liver, Thomas Starzl performed the first liver transplantations, and Henri Bismuth introduced the concept of anatomical resections. Hepatic surgery has developed significantly since those early days. To date, innovative techniques are applied, using cutting-edge technologies: Intraoperative ultrasound, techniques of vascular exclusion of the liver, new devices for performing homeostasis and dissection, laparoscopy for resections, and new drugs that allow the resection of previously unresectable tumors. The next stage in liver surgery will probably be the implementation of a multidisciplinary holistic approach to the liver-diseased patient that will ensure the best and most efficient treatments in the future.

Randomized controlled trial of ultrasonic dissection versus standard surgical technique in open left hemicolectomy or total gastrectomy

Background

Ultrasonic dissection devices have been designed for use in open surgery but it is not certain how they compare with standard surgical techniques.

Methods

This was a multicentre randomized controlled trial comparing ultrasonic dissection with the traditional surgical technique for haemostasis and dissection during left hemicolectomy and total gastrectomy. The primary endpoint was duration of operation; secondary endpoints were blood loss and other intraoperative parameters, and patient outcomes. Performance of the two techniques was rated by surgeons and assistants on a ten-point Likert scale.

Results

The analysis included 100 patients in the ultrasonic and 101 in the conventional dissection group. Patient demographics, and clinical and tumour-related parameters were similar in the two groups. There was no significant difference in duration of operation (mean 170 and 178 min in ultrasonic and conventional groups respectively; P = 0·405). Nor were there significant differences in intraoperative blood loss (median 350 and 400 ml respectively; P = 0·882), other intraoperative parameters, oncological or functional outcome. The ultrasonic dissector device was rated one point higher than conventional techniques by the surgeons.

Conclusion

Use of the ultrasonic dissector in open total gastrectomy and hemicolectomy had no impact on the overall operating time or other endpoints studied. Surgeons preferred the ultrasonic device for dissection. Registration number: ISRCTN97779420 (http://www.controlled-trials.com).

[Value of laparoscopic liver resection]

Whereas in other fields of surgery minimally invasive techniques have replaced the open surgery approach, liver resection is still a domain of conventional surgery. However, it is internationally emerging that laparoscopic hepatic surgery will become more important by conceptional improvements. This article describes the technical aspects of laparoscopic liver resection, in particular the procedure with respect to the individual liver segments. The advantages and disadvantages of the minimally invasive technique and also the indications for laparoscopic liver resection will be discussed.

Hepatic resection nomenclature and techniques

Nomenclature describing liver anatomy and liver resection has been standardized with the Brisbane 2000 terminology. When performing liver resection, blood loss should be minimized by using low central venous pressure (CVP) anesthesia and vascular occlusion as appropriate. There are many options for transection of the liver parenchyma, and although no technique has been shown to be superior to clamp-crushing, hepatic surgeons should be familiar with the techniques available.

A case of laparoscopic hepatectomy for recurrent hepatocellular carcinoma

Conventional hepatectomy is an effective way to treat hepatocellular carcinoma. However, it is invasive and stressful. The use of laparoscopy in hepatectomy, while technically demanding, reduces surgical invasiveness and stressfulness but still achieves complete resection with adequate margins. Compared with conventional hepatectomy, laparoscopic hepatectomy provides a better chance and situation for further surgery in the case of recurrence of hepatocellular carcinoma. Even aged patients can successfully endure repeated hepatectomy using laparoscopy, as shown in the present report. This report presents a case of repeated laparoscopic hepatectomy treating hepatocellular carcinoma and its recurrence in an aged patient having cirrhosis, a disease causing extra difficulty for performing laparoscopic hepatectomy. The report also describes techniques of the operation and displays characteristic results of laparoscopic hepatectomy such as smaller wounds, less blood loss, less pain, less scars and adhesion, shorter postoperative hospital stay, and faster recovery.

Intraoperative fluorescent imaging using indocyanine green for liver mapping and cholangiography

BACKGROUND

Preoperative imaging is widely used and extremely helpful in hepatobiliary surgery. However, transfer of preoperative data to a intraoperative situation is very difficult. Surgeons need intraoperative anatomical information using imaging data for safe and precise operation in the field of hepatobiliary surgery. We have developed a new system for mapping liver segments and cholangiograms using intraoperative indocyanine green (ICG) fluorescence under infrared light observation.

METHOD

The imaging technique for mapping liver segments and cholangiogram based on ICG fluorescence used an infrared-based navigation system. Eighty one patients with liver tumors underwent hepatectomy from 2006, January to 2009, March. In liver surgery, 1 ml of ICG was injected via the portal vein under observation by the fluorescent imaging system. Fourteen patients were underwent laparoscopic cholecystectomy for chronic cholecystitis with gallstones. In laparoscopic cholecystectomy, 5 ml of ICG was administered intravenously just before operation and the bile duct was observed using the infrared-based navigation system.

RESULT

This new technique successfully identified stained subsegments and segments of the liver in 73 of 81 patients (90.1%). Moreover, clear mapping of liver segments was obtained even against a background of liver cirrhosis. Fluorescent cholangiography clearly showed the common bile duct and cystic duct in 10 of 14 patients (71.4%). No adverse reactions to the ICG were encountered.

CONCLUSION

Application of this technique allows intraoperative identification of anatomical landmark in hepatobiliary surgery.

Liver Resection Using a Four-Prong Radiofrequency Transection Device

Multiple techniques are available for division of hepatic parenchyma. This is the largest United States report examining the use of the Habib 4X tissue coagulator (AngioDynamics, Queensbury, NY). The objective was to collect standard parameters associated with successful, benchmarked liver surgery outcomes using this new device, and in particular, examine the risk of margin failure. Ninety-four consecutive operations using the Habib 4X were analyzed with special attention to local failure at resection margin, blood loss/transfusion, and operative times. An institutional review board approved protocol allowed collection and analysis of demographic information and outcomes for intraoperative, perioperative, and long term follow-up. Eighteen patients had biopsy only. Thirty-one had lobar resections and 46 had wedge or segmental resections. There were 30 primary hepatic and 46 metastatic tumor diagnoses. There were a total of 33 (43%) recurrences with a mean time to recurrence of 212 days (range 15-974). Of the 27 intrahepatic recurrences, four (15%) were at the margin. The OR time ranged from 115 to 642 minutes (average 283 min). The average recorded blood loss was 427 mL; 11 patients were transfused (average 0.43 units). The Habib 4X is a safe tool to use when evaluating the parameters of blood loss, transfusion, and margin recurrence.

Bleeding and hemostasis in laparoscopic liver surgery

BACKGROUND

Minimally invasive liver resection is gaining acceptance worldwide. However, the laparoscopic approach often is reserved for small segmental resections due to the fear of significant blood loss. The expansion of laparoscopic liver surgery will depend on the ability of expert surgeons and technological advances to address the management of bleeding and hemostasis with any new approach. The 4(1/2)- year experience of a single center performing totally laparoscopic liver resections is presented, with special reference to the techniques the authors have developed to limit blood loss.

METHODS

Between 2003 and 2007, 80 patients underwent laparoscopic liver surgery for benign and malignant conditions including colorectal cancer metastases (n = 31), hepatocellular carcinoma (n = 6), neuroendocrine tumor (n = 3), cystic lesion (n = 10), adenoma (n = 8), and focal nodular hyperplasia (n = 7). Totally laparoscopic resections included sectionectomy (n = 27), hemihepatectomy (n = 10), and single/multiple segmentectomies (n = 21). Data for all resections were recorded and analyzed retrospectively to assess blood loss, hospital stay, and morbidity.

RESULTS

The median operative time was 150 min, and the median blood loss was 120 ml, with significantly more blood loss for right-sided transections than for the left liver surgery (821 vs 147 ml; p = 0.012). Four (57%) of seven resections converted to open procedures because of bleeding. No deaths occurred, and only two patients required intraoperative blood transfusions. There were eight complications and one bile leak. The median length of hospital stay was 3 days.

CONCLUSIONS

The authors' experience with 80 totally laparoscopic liver resections over a 4(1/2)-year period demonstrates that laparoscopic liver surgery is safe and effective in experienced hands for major resections. An intimate knowledge of the technology and techniques available for preventing and managing significant hemorrhage during laparoscopic liver resection is required for all surgeons performing laparoscopic liver surgery.

Resection of colorectal liver metastases: is a resection margin of 3 mm enough? : a multicenter analysis of the GAST Study Group

BACKGROUND

A safety margin of > or =10 mm is generally accepted in surgery for colorectal metastases. It is reasonable that modern methods of liver parenchyma dissection may allow for a reduction in this distance.

METHODS

A total of 333 patients were included in a multicenter trial after resection of colorectal liver metastases. Dissection of the liver had been performed with a CUSA, UltraCision, or water-jet dissector. The size of the resection margin was correlated with recurrence risk and survival.

RESULTS

The median hepatic recurrence-free survival reached 35 months for all patients; median recurrence-free survival was 24 months and overall survival was 41 months. Univariate analysis of different groups denoting the extent of resection margin (> or =10 mm, 6-9 mm, 3-5 mm, 1-2 mm, 0 mm (R1)) indicated that a margin of 1-2 mm leads to a significantly reduced median hepatic recurrence-free survival of 20 months (p = 0.004) and recurrence-free survival of 19 months (p = 0.011). Patients with R1 resection had the worst prognosis. Overall survival was not influenced by the size of the resection margin. Surgical margins were significantly reduced in simultaneous resections of four or more liver metastases and in cases in which metastatic infiltration of central liver segments was present. At multivariate analysis, resection margins of 1-2 mm and 0 mm were independent predictors of hepatic recurrence and overall recurrence.

CONCLUSION

The indication for resection of metastases can be safely extended to cases in which tumors sit closer than 1 cm to nonresectable structures.

Ultrasound scissors: new single-use instruments vs. resterilised single-use instruments - a prospective randomised study

BACKGROUND

The aim of this study was to compare reliability in handling and function of resterilised and single-use disposable ultrasonic scissors.

METHODS

In a prospective randomized study, the surgeon blindly tested new and resterilised ultrasonic scissors. The parameters were force of activation, cutting effect, coagulation effect, error messages and disturbing generator noise.

RESULTS

51 new and 49 resterilised instruments in 94 operations were evaluated. The differences in force of activation, cutting effect and coagulation were not significant. Error messages and disturbing noises were rare in both groups. 6 new instruments and 2 resterilised instruments had to be exchanged because of problems during surgery.

CONCLUSION

This study demonstrates comparable reliability in function and handling of resterilised and new ultrasonic scissors. The use of resterilised instruments leads to distinctly reduced costs and could contribute to efficiency in laparoscopic surgery.

Long-term outcome of hepatocellular carcinoma patients who underwent liver resection using microwave tissue coagulation

BACKGROUND/AIMS

Our policy for the surgical treatment of hepatocellular carcinoma (HCC) has been to minimize the extent of liver resection using a microwave tissue coagulator (MTC) and to not perform Pringle's maneuver for the prevention of ischemic injury to the liver routinely. We verify the safety of liver resection using MTC in HCC patients with poor liver functional reserve, and clarify the long-term outcome of HCC patients who underwent curative resection using MTC.

METHODOLOGY

One hundred sixty-eight patients who underwent curative resection using MTC between 1992 and 2001 were divided into two groups according each patient's score in the Indocyanin Green Retension 15 Test (ICG-R15 test). The high (ICG-R15 values>20) and low ICG-R15 groups (ICG-R15 values<20) included 100 and 68 HCC patients, respectively. Clinical characteristics of each group were evaluated, and operative mortality and morbidity, as well as overall and disease-free survival rates, were compared between the two groups to determine risk factors for overall and disease-free survival.

RESULTS

Although there were significant differences in liver function-related parameters between the low and high ICG-R15 groups, no differences in surgical or tumor factors were found. No patients in this study developed post-operative liver failure, and there was no significant difference in morbidity between the low and high ICG-R15 groups. The overall survival rate of the low ICG-R15 group was significantly longer than the high ICG-R15 group (p=0.0003). Cox's multivariate analysis showed that an ICG-R15 value less than 20 was the only significant independent factor for overall survival. Disease-free survival rates in the low ICG-R15 group were significantly longer than in the high ICG-R15 group (p=0.0007). Multivariate analysis showed that serum albumin level and number of tumors were significant independent factors for disease-free survival.

CONCLUSION

The long-term outcome of HCC patients with low ICG-R15 following curative resection using MTC was acceptable. This procedure was safe even for patients with high ICG-R15.

Open hepatic parenchymal transection using ultrasonic dissection and bipolar coagulation

Liver transection is the most challenging part of liver resection due to the risk of massive blood loss which is associated with increased postoperative morbidity and mortality, as well as reduced long-term survival after resection of malignancies. Among the devices used for open parenchyma transection, ultrasonic dissection with bipolar cautery forceps is one of the most widely used technique worldwide. We identified four retrospective comparative studies and three randomized controlled trials dealing with the efficacy of ultrasonic dissector (UD) compared with other techniques including the historical clamp crushing technique. UD is associated with similar blood loss and slower resection time compared with water-jet or clamp crushing technique. However, it seems to be more precise in dissecting vessels. Its use does not impact on morbidity and hospital stay compared with other techniques. From an economic point of view, UD is the most expensive technique and may be a disadvantage for low centre volume. UD with bipolar cautery is one of the safest and the most efficient device for liver transection, even if its superiority over the clamp crushing technique has not been well established. It is considered as a standard technique for liver transection.

Ultrasonically activated device for parenchymal division during open hepatectomy

BACKGROUND

The use of new technological devices has gained popularity and has been proposed to improve the safety of liver resection. This study was designed to evaluate the usefulness of the ultrasonically activated device (USAD) during open liver resection.

MATERIALS AND METHODS

Indication for surgery, type of resection, need to perform a Pringle manoeuvre, operation time, blood loss, number of blood transfusions, morbidity and mortality rate were analyzed in 60 patients undergoing a formal open liver resection by means of USAD.

RESULTS

The overall mean operation time was 172 minutes (range 120-255 min); an intermittent warm ischemia was applied in 9 cases (15%). The overall mean blood loss was 410 mL (median 400 mL, range 50-950 ml). A median of one blood transfusion was administered in six patients (10%). The mean hospital stay was 10.2 days (median 11, range 8-16). The overall morbidity rate was 20% (12 out of 60 patients). No in-hospital mortality was recorded. By subdividing the patients according to the presence or absence of cirrhosis no statistical significant differences were found between the two subgroups in all peri-and postoperative outcomes.

CONCLUSIONS

In conclusion, though there is a lack of data based on well conducted controlled studies and further on a greater number of patients are needed, the utilization of USAD may help to minimize blood loss during liver resection regardless of the condition of the liver, even in case of cirrhosis.

Feasibility of navigated resection of liver tumors using multiplanar visualization of intraoperative 3-dimensional ultrasound data

BACKGROUND

Intraoperative ultrasound is widely used in liver surgery, but primarily for diagnostic purposes. We have developed and evaluated a system for navigated liver resections using on intraoperatively acquired 3-dimensional (3D) ultrasound data.

METHODS

Navigation technique based on 3D ultrasound and an optical tracking system. Accuracy of the system was validated experimentally in a tumor model. Subsequently, clinical application was evaluated in 54 patients for resection of central liver tumors. Clinical feasibility and accuracy of the navigation technique were assessed with respect to practicability, adequacy of visualization, and precision of navigated resection (free margin).

RESULTS

Evaluation of the system in the tumor model showed a significant increase of the accuracy of navigated resections compared with conventional resection (P < 0.05). Clinical application of 3D ultrasound-based navigation was feasible in 52 of 54 patients. Sufficient visualization was obtained with 2 orthogonal section planes. This navigation strategy provided complete anatomic orientation and accurate position control of surgical instruments. Mean histologic resection margin was 9 mm with a maximum deviation of 8 mm from the planned virtual resection margins.

CONCLUSIONS

Optoelectronic navigation with section mode visualization in 2 orthogonal planes does sufficiently display intraoperative 3D data and enables accurate ultrasound-based navigation of liver resections.

Laparoscopic versus open liver resection for hepatocellular carcinoma in patients with histologically proven cirrhosis: short- and middle-term results

BACKGROUND

Liver surgery, especially for cirrhotic patients, is one of the last areas of resistance to progress in laparoscopic surgery. This study compares the postoperative results and the 2-year patient outcomes between laparoscopic and open resection for hepatocellular carcinoma in patients with histologically proven cirrhosis.

METHODS

From May 2000 to October 2004, 23 consecutive cirrhotic patients who underwent laparoscopic hepatectomy (LH) for HCC were compared in a retrospective analysis with a historic group of 23 patients who underwent open hepatectomy (OH). The two groups were well matched for age, gender, American Society of Anesthesiology (ASA) class, tumor location and size, type of liver resection, and severity of cirrhosis. The selection criteria for both groups specified a small (size < 5 cm), exophytic, or subcapsular tumor located in the left or peripheral right segments of the liver (II-VI segments, Couinaud); a well-compensated cirrhosis (Child-Pugh A); and an ASA score lower than 3. In the LH group, 15 subsegmentectomies, 3 segmentectomies, and 5 left lateral sectionectomies were performed, as compared with 12 subsegmentectomies, 5 segmentectomies, and 6 left lateral sectionectomies in the OH group.

RESULTS

One patient in the LH group (4.3%) underwent conversion to laparotomy for inadequate exposition. The mean operative time was statistically longer for the LH group (LH, 148 min; OH, 125 min; p = 0.016), whereas blood transfusions (LH, 0%; OH, 17.3%; p = 0.036), Pringle maneuver (LH, 0%; OH, 21.73%; p = 0.017), mean hospital stay (LH, 8.3 days; OH, 12 days; p = 0.047), and postoperative complications (LH, 13%; OH, 47.8%; p = 0.010) were significantly greater in OH group. There was no statistically significant difference in mortality and 2-year survival rates between the two groups.

CONCLUSION

This study shows that LH for HCC in properly selected cirrhotic patients results in fewer early postoperative complications and a shorter hospital stay than the traditional OH. The 2-year survival rate was the same for LH and OH.

Hepatic resections by means of electrothermal bipolar vessel device (EBVS) LigaSure V: early experience

BACKGROUND

Many techniques and devices are available for performing liver resection, such as clamp crushing, Cavitron Ultrasonic Surgical Aspirator (CUSA), Hydrojet and dissecting sealer, ultrasonic shears, and, more recently, electrothermal bipolar vessel sealing system (EBVS). In this prospective trial we sought to evaluate the impact of EBVS on hepatic resections.

METHODS

From March 2004 to December 2005, 24 patients from our consecutive liver resection series were enrolled in the present study. There were 17 males and 7 females with a mean age of 59.6 years (range = 41-80) who had colonic cancer metastases (18), hepatocarcinoma (3), angioma (2), and intrahepatic lithisasis (1). Patients were prospectively randomized to undergo liver resection via EBVS LigaSure V (12 patients, group A) or ultrasonic shears harmonic scalpel (HS) (12 patients, group B). Hepatic procedures did not differ significantly between the two groups and were as follows: right hepatectomy (2), left hepatectomy (1), bisegmentectomy (14), and segmentectomy (7).

RESULTS

There was no mortality in either group. The mean operative time was 136.7 min (range = 90-210) in group A and 187.9 min (range = 130-360) in group B. The Pringle maneuver was done in five patients in group A [mean time = 11.4 min (range = 6-12)] and in four patients in group B [mean time = 16 min (range = 9-26)]. The mean blood loss, total bile salts, and hemoglobin concentration from drained fluid on the second postoperative day were 205.8 vs. 506.7 ml, 0.6 vs. 1.1 mmol/L, and 1.0 vs. 2.1 g/L (p < 0.05) for groups A and B, respectively. Mean postoperative hospital stay was 6.1 vs. 7.8 days. In group B a patient who underwent right hepatectomy for colon cancer metastases had transient hepatic failure. No patients received blood transfusions in group A, while two or more blood units were administered in two cases in group B.

CONCLUSIONS

In the present study EBVS proved to be safe and effective for liver resection. By means of this device, statistically significant benefits concerning blood loss, total bile salts, and hemoglobin postoperative leakage were found.