Transumbilical endoscopic surgery: History, present situation and perspectives

Transumbilical videolaparoscopic (single site) liver biopsy with laparoscopy equipment

INTRODUCTION

Liver diseases have a high incidence in the whole world. In order to diagnose, stage and follow these diseases it is often necessary the execution of liver biopsy. There are many possible ways to perform the procedure and the rise of transumbilical endoscopic surgery (TUES) brings to the medical practice an additional good option.

MATERIALS AND METHODS

The study is prospective, nonrandomised and cohort type. It involves 42 patients who underwent liver biopsy through TUES using conventional video laparoscopic material.

RESULTS

Among the patients 18 (42.86%) underwent isolated liver biopsy and 24 (57.14%) to liver biopsy associated with umbilical hernia repair. Within those, 27 (64.28%) were male and 15 (35.71%) female. The average body mass index (BMI) was of 27.26 kg/m(2), 10 were in the normal BMI range, 24 (57.14%) were in the overweight range, 6 (14.28%) had class I obesity and 2 (4.76%) had class II obesity. In none of the cases the procedure was converted to regular video laparoscopy, all the patients were discharged in the day after the procedure and reported a satisfactory aesthetic result.

CONCLUSIONS

The study shows that liver biopsy using TUES has applicability and good results, including in obese patients that would have a contraindication to other methods.

Analysis of the structural behaviour of colonic segments by inflation tests: Experimental activity and physio-mechanical model

A coupled experimental and computational approach is provided for the identification of the structural behaviour of gastrointestinal regions, accounting for both elastic and visco-elastic properties. The developed procedure is applied to characterize the mechanics of gastrointestinal samples from pig colons. Experimental data about the structural behaviour of colonic segments are provided by inflation tests. Different inflation processes are performed according to progressively increasing top pressure conditions. Each inflation test consists of an air in-flow, according to an almost constant increasing pressure rate, such as 3.5 mmHg/s, up to a prescribed top pressure, which is held constant for about 300 s to allow the development of creep phenomena. Different tests are interspersed by 600 s of rest to allow the recovery of the tissues' mechanical condition. Data from structural tests are post-processed by a physio-mechanical model in order to identify the mechanical parameters that interpret both the non-linear elastic behaviour of the sample, as the instantaneous pressure-stretch trend, and the time-dependent response, as the stretch increase during the creep processes. The parameters are identified by minimizing the discrepancy between experimental and model results. Different sets of parameters are evaluated for different specimens from different pigs. A statistical analysis is performed to evaluate the distribution of the parameters and to assess the reliability of the experimental and computational activities.

Single-site laparoscopic colectomy for rectosigmoid cancer with middle aortic syndrome: report of a case

Introduction

Single-site laparoscopic colectomy (SLC) is a promising minimally invasive and safe treatment for colorectal cancer. Improvements of the working instruments and procedures for SLC have helped to overcome challenges regarding the difficulty of operation, supporting the gradual acceptance of this technique. In contrast, narrow working space of the abdominal cavity sometimes prevents securing an adequate surgical view. To obtain precise anatomical information and enable complete mesocolic excision (CME), we routinely perform three-dimensional computed tomography prior to SLC.

Case presentation

A 69-year-old Japanese woman was clinically diagnosed with rectosigmoid cancer. Unexpectedly, preoperative examination revealed asymptomatic stenosis of the great artery, which was diagnosed as middle aortic syndrome. Because radical colectomy requires dissection of vessels that supply blood flow to the legs, a vascular stent was inserted prior to operation. We chose SLC due to the reduced risk of damaging epigastric arteries, which may eventually become collaterals in the event of stent re-stenosis. We accomplished SLC with CME, and the patient was discharged on the tenth day after operation without complications.

Conclusion

The present case is the first to proceed by SLC for colorectal cancer complicated by vascular obstructive disease. Preoperative imaging enabled us to identify an unexpected rare disease and to still accomplish SLC with CME, thus reinforcing the importance of preoperative imaging to optimize the use of SLC. In addition, SLC may become one of the most adequate procedures for patients complicated by vascular obstructive disease.

Single incision transumbilical laparoscopic varicocelectomy versus the conventional laparoscopic technique: A randomized clinical study

BACKGROUND

Varicocele is the most common correctable cause of infertility. We analyzed the outcomes of single incision laparoscopic varicocelectomy (SIL-V) in comparison with conventional transperitoneal varicocelectomy (CTL-V).

METHODS

Patients with clinically palpable varicocele treated by laparoscopic varicocelectomy were randomly allocated into two groups: SIL-V and CTL-V group. The primary outcome measures were improvement in semen parameters and resolution of testicular pain. Secondary outcome measures included operating time, postoperative pain scores, time to return to normal activity, patient satisfaction and postoperative complications.

RESULTS

Eighty patients completed the study. No vascular or intestinal complications occurred during both procedures. All patients were discharged 24 h postoperatively. The parameters measuring the success of varicocelectomy had improved for the majority of patients with no significant difference between the two groups. There was significantly longer operating time in SIL-V group (44.6 ± 5.4 min) than in CTL-V group (41.3 ± 8.5 min) (P = 0.03). The difference in operating time was lost when bilateral procedures were compared (P = 0.21). The mean VAS scores for pain at 3, 24 and 48 h postoperatively were significantly lower in SIL-V group (P = 0.02, P = 0.03 and P < 0.001 respectively). Time to return to normal activity was significantly shorter in SIL-V (P < 0.001). Patient satisfaction was significantly higher in SIL-V group (P < 0.01). Postoperative complications were comparable in both groups.

CONCLUSION

SIL-V is a safe and effective straightforward alternative to the well-established and accepted CTL-V. The tendency toward decreased postoperative pain, rapid return to normal activity and the high patients' satisfaction rate regarding cosmetic results are potential benefits of SIL-V procedure.

CLINICAL TRIAL

(NCT02335385).

Miniature Surgical Robots in the Era of NOTES and LESS

Laparoscopy is an established method for the treatment of numerous surgical conditions. Natural orifice transluminal endoscopic surgery (NOTES) is a novel surgical technique that uses the natural orifices of the human body as entrances to the abdominal cavity. An alternative concept of minimally invasive approach to the abdominal cavity is to insert all the laparoscopic instruments through ports using a single small incision on the abdominal wall. A suggested name for this technique is laparoendoscopic single-site surgery (LESS). Considering the technical difficulties in NOTES and LESS and the progress in informatics and robotics, the use of robots seems ideal. The aim of this study is to investigate if there is at present, a realistic possibility of using miniature robots in NOTES or LESS in daily clinical practice. An up-to-date review on in vivo surgical miniature robots is made. A Web-based research of the English literature up to March 2013 using PubMed, Scopus, and Google Scholar as search engines was performed. The development of in vivo miniature robots for use in NOTES or LESS is a reality with great advancements, potential advantages, and possible application in minimally invasive surgery in the future. However, true totally NOTES or LESS procedures on humans using miniature robots either solely or as assistance, remain a dream at present.

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.

Miniature Surgical Robots in the Era of NOTES and LESS

Laparoscopy is an established method for the treatment of numerous surgical conditions. Natural orifice transluminal endoscopic surgery (NOTES) is a novel surgical technique that uses the natural orifices of the human body as entrances to the abdominal cavity. An alternative concept of minimally invasive approach to the abdominal cavity is to insert all the laparoscopic instruments through ports using a single small incision on the abdominal wall. A suggested name for this technique is laparoendoscopic single-site surgery (LESS). Considering the technical difficulties in NOTES and LESS and the progress in informatics and robotics, the use of robots seems ideal. The aim of this study is to investigate if there is at present, a realistic possibility of using miniature robots in NOTES or LESS in daily clinical practice. An up-to-date review on in vivo surgical miniature robots is made. A Web-based research of the English literature up to March 2013 using PubMed, Scopus, and Google Scholar as search engines was performed. The development of in vivo miniature robots for use in NOTES or LESS is a reality with great advancements, potential advantages, and possible application in minimally invasive surgery in the future. However, true totally NOTES or LESS procedures on humans using miniature robots either solely or as assistance, remain a dream at present.

Mechanical Evaluation of Articulating Instruments and Cross-Handed Manipulation in Laparoendoscopic Single-Site Surgery

Background. Laparoendoscopic single-site surgery (LESS) is limited by loss of triangulation and internal instruments conflict. To overcome these difficulties, some concepts have been introduced, namely, articulating instruments and cross-handed manipulation, which causes the right hand to control the left instrument tip and vice versa. The aim of this study was to compare task performance with different approaches based on a mechanical evaluation platform. Methods. A LESS mechanical evaluation platform was set up to investigate the performance of 2 tasks (suture pass-through rings and clip-cut) with 3 different settings: uncrossed manipulation with straight instruments (group A, the control group), uncrossed manipulation with articulating instruments (group B), and cross-handed manipulation with articulating instruments (group C). The operation time and average load required for accomplishment of the standard tasks were measured. Results. Group A presented significantly better time scores than group B, and group C consumed the longest time to accomplish the 2 tasks ( P < .05). Comparing of average load required to perform the suture pass-through rings task, it differed significantly between dominant and nondominant hand in all groups ( P < .01) and was less in group A and group B than group C in dominant hand ( P < .01), while it was almost the same in all groups in the nondominant hand. In terms of average load requirement to accomplish clip-cut task, it was almost equal not only between group A and B but also between dominant and nondominant hand while the increase reached statistical significance when comparing group C with other groups ( P < .05). Conclusions. Compared with conventional devices and maneuvering techniques, articulating instruments and cross-handed manipulation are associated with longer operation time and higher workload. Instruments with better maneuverability should be developed in the future for LESS.

Constitutive formulations for the mechanical investigation of colonic tissues

A constitutive framework is provided for the characterization of the mechanical behavior of colonic tissues, as a fundamental tool for the development of numerical models of the colonic structures. The constitutive analysis is performed by a multidisciplinary approach that requires the cooperation between experimental and computational competences. The preliminary investigation pertains to the review of the tissues histology. The complex structural configuration of the tissues and the specific distributions of fibrous elements entail the nonlinear mechanical behavior and the anisotropic response. The identification of the mechanical properties requires to perform mechanical tests according to different loading situations, as different loading directions. Because of the typical functionality of colon structures, the tissues mechanics is investigated by tensile tests, which are performed on taenia coli and haustra specimens from fresh pig colons. Accounting for the histological investigation and the results from the mechanical tests, a specific hyperelastic framework is provided within the theory of fiber-reinforced composite materials. Preliminary analytical formulations are defined to identify the constitutive parameters by the inverse analysis of the experimental tests. Finite element models of the specimens are developed accounting for the actual configuration of the colon structures to verify the quality of the results. The good agreement between experimental and numerical model results suggests the reliability of the constitutive formulations and parameters. Finally, the developed constitutive analysis makes it possible to identify the mechanical behavior and properties of the different colonic tissues.