Evaluation of a calibration rig for stereo laparoscopes.

BACKGROUND: Accurate camera and hand-eye calibration are essential to ensure high-quality results in image-guided surgery applications. The process must also be able to be undertaken by a nonexpert user in a surgical setting. PURPOSE: This work seeks to identify a suitable method for tracked stereo laparoscope calibration within theater. METHODS: A custom calibration rig, to enable rapid calibration in a surgical setting, was designed. The rig was compared against freehand calibration. Stereo reprojection, stereo reconstruction, tracked stereo reprojection, and tracked stereo reconstruction error metrics were used to evaluate calibration quality. RESULTS: Use of the calibration rig reduced mean errors: reprojection (1.47 mm [SD 0.13] vs. 3.14 mm [SD 2.11], p-value 1e-8), reconstruction (1.37 px [SD 0.10] vs. 10.10 px [SD 4.54], p-value 6e-7), and tracked reconstruction (1.38 mm [SD 0.10] vs. 12.64 mm [SD 4.34], p-value 1e-6) compared with freehand calibration. The use of a ChArUco pattern yielded slightly lower reprojection errors, while a dot grid produced lower reconstruction errors and was more robust under strong global illumination. CONCLUSION: The use of the calibration rig results in a statistically significant decrease in calibration error metrics, versus freehand calibration, and represents the preferred approach for use in the operating theater.

A comparative study of the short-term operative outcome between intracorporeal and extracorporeal anastomoses during laparoscopic total gastrectomy.

BACKGROUND: Several studies have reported that intracorporeal anastomosis reduces the requirement for the additional incision for anastomosis, resulting in early recovery compared to extracorporeal anastomosis during laparoscopic distal gastrectomy. However, few studies have investigated postoperative outcome after laparoscopic total gastrectomy (LTG). We compared short-term postoperative outcomes between totally laparoscopic total gastrectomy (TLTG) with intracorporeal anastomosis and conventional laparoscopy-assisted total gastrectomy (LATG) with extracorporeal anastomosis for gastric cancer. METHODS: This retrospective case-control study included 202 patients who underwent LTG from January 2012 to June 2019. LATG was performed in the period before July 2015; TLTG was performed in the period after July 2015. Postoperative short-term outcomes and white blood cell (WBC) count, and C-reactive protein (CRP) levels at 1, 3, and 5 days postoperatively were compared between the groups. RESULTS: One hundred ten patients underwent LATG; 92 underwent TLTG. The pathologic stage was significantly higher in the TLTG group (p = 0.010). Intraoperative estimated blood loss was significantly lower in the TLTG group than in the LATG group (median [range]: 100 [50-150] mL versus [vs.] 50 [30-100], p < 0.001). Postoperative hospital stay duration was significantly longer in the TLTG group than in the LATG group (median [range]: 7 [7-9] days vs. 8 [7-11], p < 0.001). WBC count (6.3 109/L ± 1.9 vs. 8.2 ± 2.5, p = 0.004) and CRP levels (8.3 mg/L ± 6.1 vs. 13.3 ± 9.4, p < 0.001) were lower in the LATG group than in the TLTG group. The overall complication rate was higher in the TLTG group than in the LATG group (16.3% vs. 32.6%, p = 0.007). A higher American Society of Anesthesiologist score was the only significant risk factor for postoperative complications. CONCLUSION: Both procedures are feasible, although TLTG has more risk for postoperative complications than LATG. TLTG should be improved to reduce postoperative complications and provide better postoperative outcomes.

Adaptive Fusion-Based Autonomous Laparoscope Control for Semi-Autonomous Surgery.

The purpose of this paper is to develop an autonomous tracking algorithm based on adaptive fusion kinematics method, the autonomous laparoscope control algorithm and adaptive fusion kinematics method are proposed for semi-autonomous surgery, focus on solving the problems of autonomous laparoscope field of view control for surgical robot system. A novel autonomous tracking algorithm is proposed. To realize more robust tracking, an adaptive fusion kinematics method based on fuzzy logic is proposed, the method adaptive associates the kinematics information of surgical robot system and the laparoscope information. The proposed methods are implemented on the laparoscopic minimally invasive surgical robot system which is developed by our laboratory. Two experiments are carried out, the results indicate that the accurate autonomous field of view control is achieved with the addition of laparoscope information, laparoscopic motion frequency is reduced, the methods can avoid the laparoscope continuous motion and ensure the stability of field of view. The proposed methods improve the intelligence level of surgical robot system.

Design and Evaluation of FBG-Based Tension Sensor in Laparoscope Surgical Robots.

Due to the narrow space and a harsh chemical environment in the sterilization processes for the end-effector of surgical robots, it is difficult to install and integrate suitable sensors for the purpose of effective and precise force control. This paper presents an innovative tension sensor for estimation of grasping force in our laparoscope surgical robot. The proposed sensor measures the tension of cable using fiber gratings (FBGs) which are pasted in the grooves on the inclined cantilevers of the sensor. By exploiting the stain measurement characteristics of FBGs, the small deformation of the inclined cantilevers caused by the cable tension can be measured. The working principle and the sensor model are analyzed. Based on the sensor model, the dimensions of the sensor are designed and optimized. A dedicated experimental setup is established to calibrate and test the sensor. The results of experiments for estimation the grasping force validate the sensor.

Laparoscopic lens fogging: solving a common surgical problem in standard and robotic laparoscopes via a scientific model.

BACKGROUND: Laparoscopic lens fogging (LLF) hampers vision and impedes operative efficiency. Attempts to reduce LLF have led to the development of various anti-fogging fluids and warming devices. Limited literature exists directly comparing these techniques. We constructed a model peritoneum to simulate LLF and to compare the efficacy of various anti-fogging techniques. MATERIALS AND METHODS: Intraperitoneal space was simulated using a suction bag suspended within an 8 L container of water. LLF was induced by varying the temperature and humidity within the model peritoneum. Various anti-fogging techniques were assessed including scope warmers, FREDTM, ResoclearTM, chlorhexidine, betadine and immersion in heated saline. These products were trialled with and without the use of a disposable scope warmer. Vision scores were evaluated by the same investigator for all tests and rated according to a predetermined scale. Fogging was assessed for each product or technique 30 times and a mean vision rating was recorded. RESULTS: All products tested imparted some benefit, but FREDTM performed better than all other techniques. Betadine and ResoclearTM performed no better than the use of a scope warmer alone. Immersion in saline prior to insertion resulted in decreased vision ratings. The robotic scope did not result in LLF within the model. CONCLUSIONS: In standard laparoscopes, the most superior preventative measure was FREDTM utilised on a pre-warmed scope. Despite improvements in LLF with other products FREDTM was better than all other techniques. The robotic laparoscope performed superiorly regarding LLF compared to standard laparoscope.

Prospective, randomized comparison of the use of FloShield Air System® versus the reference technique (water + povidone-iodine solution) during gynecologic endoscopic surgery to evaluate the operative lens vision quality.

BACKGROUND: The FloShield Air System® is a new device for laparoscopic surgery that utilizes a continuous dry CO2 gas flow over the scope to defog the lens and protect it from condensation, debris and smoke. We set out to compare the performance and efficiency of the device in terms of operative lens vision quality (OLVQ) with the reference technique (water + povidone-iodine (PVI) solution) during gynecologic laparoscopic surgery. MATERIALS AND METHODS: We conducted a single-center randomized prospective study between March and June 2016 (Trials Database Registration NCT02702531) including 53 patients undergoing gynecologic laparoscopic surgery with water + PVI solution and 51 patients who underwent surgical procedures with the FloShield Air System. The primary outcome measure was the number of laparoscope removals during surgery. Secondary outcome measures were the time to clean, assessment of the quality of vision, the correlation between the laparoscopic surgical complexity and outcomes, and cost effectiveness. RESULTS: Overall, the mean patient age was 43.2 years (range 22-86) and body mass index 24.8 (range 16.8-42.7). The mean number of endoscope removals during surgery was 7.0 (range 0-37) in the water + PVI solution arm and 2.8 (range 0-12) in the FloShield Air System® arm. The number of removals was significantly lower in the FloShield arm (p < 0.001). No difference in time to clean, quality of vision, level of laparoscopic procedure complexity, or cost was observed between the groups. CONSLUSIONS: The FloShield Air System® resulted in fewer laparoscopic lens removals than the water + PVI solution solution, but that there was no difference in quality of vision, cleaning time or cost, especially for the more complex surgery.

Research and development of a laparoscopic surgical device for ligating endless organs based on a flexible structure.

While laparoscopic surgery has become increasingly widely used, many laparoscopic procedures are time-consuming and difficult to accomplish compared to open surgery. One such procedure is the ligation of endless organs. In this paper, the development and prototyping of a laparoscopic instrument that could significantly increase the efficiency of laparoscopic ligation is outlined. The mechanism is based on a snake-like flexible structure which is actuated by control wires. A simple simulation was carried out by both experienced surgical staff as well as non-surgical persons to confirm the effectiveness of the proposed mechanism.

The effect of ergonomic laparoscopic tool handle design on performance and efficiency.

BACKGROUND: Many factors can affect a surgeon's performance in the operating room; these may include surgeon comfort, ergonomics of tool handle design, and fatigue. A laparoscopic tool handle designed with ergonomic considerations (pistol grip) was tested against a current market tool with a traditional pinch grip handle. The goal of this study is to quantify the impact ergonomic design considerations which have on surgeon performance. We hypothesized that there will be measurable differences between the efficiency while performing FLS surgical trainer tasks when using both tool handle designs in three categories: time to completion, technical skill, and subjective user ratings. METHODS: The pistol grip incorporates an ergonomic interface intended to reduce contact stress points on the hand and fingers, promote a more neutral operating wrist posture, and reduce hand tremor and fatigue. The traditional pinch grip is a laparoscopic tool developed by Stryker Inc. widely used during minimal invasive surgery. Twenty-three (13 M, 10 F) participants with no existing upper extremity musculoskeletal disorders or experience performing laparoscopic procedures were selected to perform in this study. During a training session prior to testing, participants performed practice trials in a SAGES FLS trainer with both tools. During data collection, participants performed three evaluation tasks using both handle designs (order was randomized, and each trial completed three times). The tasks consisted of FLS peg transfer, cutting, and suturing tasks. RESULTS: Feedback from test participants indicated that they significantly preferred the ergonomic pistol grip in every category (p < 0.05); most notably, participants experienced greater degrees of discomfort in their hands after using the pinch grip tool. Furthermore, participants completed cutting and peg transfer tasks in a shorter time duration (p < 0.05) with the pistol grip than with the pinch grip design; there was no significant difference between completion times for the suturing task. Finally, there was no significant interaction between tool type and errors made during trials. CONCLUSIONS: There was a significant preference for as well as lower pain experienced during use of the pistol grip tool as seen from the survey feedback. Both evaluation tasks (cutting and peg transfer) were also completed significantly faster with the pistol grip tool. Finally, due to the high degree of variability in the error data, it was not possible to draw any meaningful conclusions about the effect of tool design on the number or degree of errors made.

Development of a measurement system for laparoendoscopic single-site surgery: reliability and repeatability of digital image correlation for measurement of surface deformations in SILS port.

OBJECTIVE: Analysis of mechanical measurements in laparoendoscopic single-site surgery (LESS) is important for instrument design and surgical simulators. The aim of this study was to develop a measuring system for different instruments and manipulations in LESS using a single-incision laparoscopic surgery (SILS) port. METHODS: The loads on the SILS port were applied and recorded by the universal material testing machine by the following method. The handle of the forceps inserted in the SILS port was connected with the machine by a fishing wire and pulled at a constant rate. The surface deformations (displacements and strains) of the SILS port were recorded with digital image correlation (DIC) simultaneously. The correlation between deformation measurements and loads were analyzed. This experiment was repeated 8 times. RESULTS: Strong correlations existed between deformation measurements calculated by DIC and objective criteria "loads" applied and recorded by the universal material testing machine (r>0.98). The correlation coefficients were statistically significant (P<.001). A high repeatability of the results appeared in all repetitions of the experiment. CONCLUSIONS: A DIC measurement system has been developed for LESS, and comprehensive mechanical parameters of a SILS port can be obtained precisely by using this system. It is reliable and repeatable for evaluation of instruments and manipulations in LESS.

[Single laparoscopic approach in newborns and infants].

The aim of this investigation is evidence of opportunity of single laparoscopic approach using during operations in newborns and infants. The authors have an experience of 274 single-port operations performed from January 2009 to December 2013. Success of single laparoscopic approach has been demonstrated in patients with inguinal hernia, congenital hypertrophic pyloric stenosis, feeding violations, ovarian cyst and multi-cystic kidney dysplasia.

Diagnostic laparoscopy in the cat: 1. Rationale and equipment.

PRACTICAL RELEVANCE: The integration of minimally invasive techniques into feline practice seems to be an intuitive step forward, especially for those cases where the owner may be reluctant to subject their cat to major surgery 'just for a biopsy'. Although ultrasound is frequently employed as a diagnostic tool in similar cases, this modality can only provide information on gross abnormalities in organ size and shape, echogenicity and internal architecture; even with ultrasound-guided fine-needle aspiration a definitive diagnosis is rarely achieved. So the clinician and owner are left with unanswered questions that are central to the diagnosis, the most appropriate treatment to pursue and the prognosis for the cat. Laparoscopy does require anesthesia and is more expensive than ultrasound; however, when performed correctly, it is only marginally more invasive and vastly more informative, with a proven track record of minimal morbidity. AUDIENCE: This article is aimed at all feline practitioners, from first opinion through to the referral setting. It is intended to encourage practitioners untrained in minimally invasive procedures to seek formalized training, especially those who want to expand their diagnostic capabilities. For those already performing minimally invasive surgery, it describes how laparoscopic techniques can be applied to many feline gastrointestinal cases. EVIDENCE BASE: Information provided in this article is based on published literature, comprising original studies, case review series and textbook chapters, and the authors' own clinical experience.

Diagnostic laparoscopy in the cat: 2. Common procedures.

PRACTICAL RELEVANCE: Minimally invasive techniques are becoming increasingly available in both first opinion and referral veterinary surgeries. Clients may be reluctant to pursue open surgery for the collection of biopsy samples in a sick cat but may be more open to a laparoscopic approach. Furthermore, a laparoscopic approach provides excellent visualization of the abdominal organs and enables high quality biopsies to be taken that are invariably more diagnostic than percutaneous needle biopsies. Although the feline patient is small in size, its distensible abdomen allows more room for surgical manipulation than afforded by a similar sized canine patient. CLINICAL CHALLENGES: Clinical challenges for the most part relate to mastering laparoscopic technique. Familiarity with the use of long instrumentation viewed on a two-dimensional screen is essential. Hemostasis is an important consideration and suitable instrumentation for achieving hemostasis should be available at all times. Insufflation of the abdomen carries its own challenges with regard to anesthesia and this is covered in an accompanying article in this Special Issue series. AIM: This article introduces the feline practitioner to basic techniques required to effectively utilize diagnostic laparoscopy within feline medical investigations. It focuses on the common procedures of liver biopsy, cholecystocentesis, pancreatic biopsy, kidney biopsy and laparoscopic-assisted intestinal biopsy. EVIDENCE BASE: Information provided in this article is drawn from the published literature and the authors' own clinical experience.

Optical performance comparison of deflectable laparoscopes for laparoendoscopic single-site surgery.

BACKGROUND AND PURPOSE: Flexible working angles and fine optical visualization are major requisite factors in performing laparoendoscopic single-site (LESS) urologic procedures. Multiple mechanical design approaches have been used to develop deflectable laparoscopes for LESS procedures. We compared the optical characteristics of three such devices using a bench top approach to simulate LESS in straight and deflected positions. MATERIALS AND METHODS: A 10-mm fixed-rod rotating lens device (Storz EndoCameleon) and two 5-mm articulating devices (Olympus EndoEye and Stryker IdealEye) were compared using standard industry testing protocols for image resolution (United States Air Force-1951 test target), distortion (multifrequency grid distortion target), and color reproducibility (Gretag Macbeth color checker). RESULTS: The 10-mm fixed-rod rotating lens system demonstrated the highest image resolution (5.04 line pairs/mm), but also the highest distortion (22.8%). Among the 5-mm flexible articulating laparoscopes, resolution was superior with the Olympus EndoEye (4.00 line pairs/mm) compared with the Stryker IdealEye (3.17 line pairs/mm). Distortion (7.0%) and color reproduction (1.18) were superior with the IdealEye vs the EndoEye (18.8 %, 1.27). Laparoscope deflection resulted in attenuation of resolution by 11% with both articulating models, but not with the fixed rod system. CONCLUSIONS: Definition of these optical characteristics may inform further development and selection of laparoscopic systems optimized for LESS surgery. A narrow but flexible camera can be crucial in the limited working space available during these procedures. Further investigation is warranted to determine if these objective findings translate into improved surgeon performance.

Single-site laparoscopic (SSL) cholecystectomy in human cadavers using a novel percutaneous instrument platform and a magnetic anchoring and guidance system (MAGS): reestablishing the "critical view".

INTRODUCTION: SSL introduces ergonomic challenges while establishing the critical view during dissection of the Triangle of Calot (TOC). This study investigates the use of a novel percutaneous instrument platform and MAGS in performing SSL cholecystectomy with a technique that closely mimics four-port cholecystectomy. METHODS: SSL cholecystectomy was performed on four female cadavers via a 15-18-mm incision made at the umbilicus for introduction of these devices and the working port. MAGS comprises an internal effector with a retractable monopolar cautery hook coupled across the abdominal wall to an external magnet held by the surgeon. The novel grasper was introduced percutaneously in the RUQ and comprises a 3-mm transabdominal shaft mated to a 5-mm end effector intracorporeally. Retraction was accomplished using the percutaneous grasper to manipulate the fundus and a standard 5-mm grasper at the umbilicus for the infundibulum. Dissection was performed by using a combination of the MAGS and a standard Maryland dissector. Total procedure time, time from procedure start to obtain a critical view of the TOC and clipping and dividing the cystic duct/artery, time for dissection of the gallbladder from the liver bed, and thickness of the abdominal wall at the umbilicus were measured. RESULTS: The critical view was obtained in each case, and all four procedures were completed successfully. Mean procedure time was 40 (range, 33-51) min; time from procedure start to obtaining the critical view and clipping and dividing the cystic duct/artery was 33 (range, 28-38) min, and time for dissection of the gallbladder from the liver bed was 6.7 (range, 3-13) min. The mean abdominal wall thickness was 1.9 (range, 1.5-2) cm. CONCLUSIONS: The use of a novel graspers and MAGS overcomes the limitations of SSL cholecystectomy and improves surgeon dexterity. Making SSL feel more like traditional laparoscopy will enable a wider adoption of this procedure in the community.

Reevaluation of needlescopic surgery.

BACKGROUND: Although the use of single-incision laparoscopic surgery (SILS) has spread rapidly, most procedures employ additional needlescopic instruments to ensure safety and shorten the operation time. Therefore, on the basis of results obtained in our department, the present study was conducted to reevaluate the current state of needlescopic surgery (NS) to improve the cosmetic results and postoperative quality of life of patients and to reduce cost and degree of stress on surgeons. METHODS: Between May 1998 and February 2011, we performed NS in 202 patients. The diagnoses included gallbladder diseases in 151 patients, spontaneous pneumothorax in 11, thyroid tumor and axillary lymph node metastases in 10 patients each, splenic cyst and appendicitis in 4 patients each, idiopathic thrombocytopenic purpura and postoperative abdominal wall hernia in 3 patients each, primary aldosteronism and hepatic cyst in 2 patients each, and adhesional bowel obstruction and gastric stromal tumor in 1 patient each. Under general anesthesia, one 12-mm and tow or three 2- or 3-mm ports were introduced into the operative field. The specimen was retrieved via the 12-mm wound using a plastic bag. RESULTS: The operations were completed in all patients without the need to convert to an open procedure. In 8 (5.3%) of the 151 cholecystectomies, a change to 5-mm instruments was required. There were no perioperative complications. Pertinent technical points included avoidance of direct organ mobilization to minimize injury, rotation of the operating table and utilization of organ gravity to create a better operative field, minimum use of needlescope to ensure safe maneuvering, and improvement of the bi-hand technique. CONCLUSIONS: NS is a safe and feasible procedure that allows experienced surgeons to achieve minimally invasive surgery with low morbidity, without the need to convert to a conventional or open procedure.

Laparoendoscopic single site surgery can be performed completely with standard equipment.

PURPOSE: To determine the feasibility of laparoendoscopic single site surgery (LESS) with nonarticulating instruments and conventional trocars. METHODS: After Institutional Review Board approval, a prospective database was used to identify 30 patients who underwent LESS. All procedures were begun using three 5 mm trocars, nonarticulating instruments, and a 5 mm, 30-degree laparoscope. RESULTS: Twenty-six patients underwent LESS cholecystectomy. Four patients underwent LESS appendectomy; 2 for acute appendicitis and 2 for interval appendectomy. The mean patient age was 37.1 ± 14 years for the cholecystectomy group and 29.3 ± 2.2 years for the appendectomy group. Mean body mass index was 28.4 ± 7 kg/m2 for the cholecystectomy group and 25 ± 5.6 kg/m2 for the appendectomy group. Eight patients (31%) undergoing LESS cholecystectomy required an additional 5 mm port; 6 (26%) required 1 additional port for gallbladder retraction, 1 case (4%) required 2 additional ports to control cystic artery bleeding, and 1 case (4%) was converted to a traditional 4 trocar cholecystectomy because of chronic inflammation and multiple adhesions. None of the patients in the appendectomy group required an additional port. The mean operative time was 94 ± 19 minutes for cholecystectomy and 65 ± 19 minutes for appendectomy. Ninety-two percent (N=24) of patients in the laparoscopic cholecystectomy group were discharged within 24 hours. One patient underwent postoperative endoscopic retrograde cholangiopancreatography with bile duct stone removal and was discharged after 48 hours. One patient remained until postoperative day 2 for pain control. All patients in the LESS appendectomy group were discharged within 24 hours. There were no postoperative complications. CONCLUSIONS: Although operative time for LESS is increased compared with laparoscopic cholecystectomy and appendectomy, LESS can be performed safely. In our institutional experience, LESS was successfully performed using standard laparoscopic instruments, laparoscope, and trocars. Although longer follow-up is necessary, early data supports the feasibility and safety of LESS. A low threshold should exist for the addition of extra trocars, especially during a surgeon's early experience with LESS.

[Laparoscopic surgery in regions: problems and ways of development].

The modern state of laparoscopic surgery in northern regions (Komi republic, Murmansk, Arkhangelsk and Vologda regions) of Russian Federation was surveyed according to the reports of 1998-2007 and 2009 years. Thus, the investigation revealed, that not more than 30% of general surgeons are handle laparoscopic technique. Laparoscopic procedures comprise about 20% of all abdominal operations in the surveyed regions. Statictically significant differences in the use of laparoscopic surgery were revealed between the regions (p<0,001). In 2009 laparoscopically treated were: 82-98,5% cases of chronic calculous cholecystitis; 37,5-70,3% cases of the acute calculous cholecystitis; 1,0-10,7% of the acute appendicitis and 0,5-7,8% of patients with perforated ulcer. Nevertheless, the increase of the laparoscopic share is statistically expected within 5 next years.

Comparison of two- and three-dimensional camera systems in laparoscopic performance: a novel 3D system with one camera.

BACKGROUND: This study evaluated the effects of a three-dimensional (3D) imaging system on laparoscopy performance compared with the conventional 2D system using a novel one-camera 3D system. METHODS: In this study, 21 novices and 6 experienced surgeons performed two tasks with 2D and 3D systems in 4 consecutive days. Performance time and error as well as subjective parameters such as depth perception and visual discomforts were assessed in each session. Electromyography was used to evaluate the usage of muscles. RESULTS: The 3D system provided significantly greater depth perception than the 2D system. The errors during the two tasks were significantly lower with 3D system in novice group, but performance time was not different between the 2D and 3D systems. The novices had more dizziness with the 3D system in first 2 days. However, the severity of dizziness was minimal (less than 2 of 10) and overcome with the passage of time. About 54% of the novices and 80% of the experienced surgeons preferred the 3D system. Electromyography (EMG) showed a tendency toward less usage of the right arm and more usage of the left arm with the 3D system. CONCLUSION: The new 3D imaging system increased the accuracy of laparoscopy performance, with greater depth perception and only minimal dizziness. The authors expect that the 3D laparoscopic system could provide good depth perception and accuracy in surgery.