Laparoscopic intracorporal colorectal sutured anastomosis using the Radius Surgical System in a phantom model.

BACKGROUND: The Radius Surgical System (RSS) is a manipulator with additional degrees of freedom to enhance the dexterity of laparoscopic suturing. Our aim was to determine the feasibility and potentially added value of laparoscopic intracorporal sutured colorectal anastomosis (RSS) compared with suturing with conventional laparoscopic instruments (CLI). METHODS: A total of 72 colorectal anastomoses and 30 single sutures using RSS and CLI were performed in the study. The experiment was divided as follows: One surgeon performed 40 colorectal anastomoses using RSS to assess the learning curve and the feasibility of the technique; The same surgeon performed 10 additional colorectal anastomoses with CLI which were then compared to the last 10 cases of the 40 anastomoses with RSS; Fifteen single sutures in the horizontal plane with RSS and 15 with CLI between two segments of colon were performed to compare the traction force to disrupt the suture; Twelve anastomoses were performed by the other three participants to evaluate ergonomy. RESULTS: Three leakages (7.5%) were found in the 40 anastomoses with RSS but none after the eighth case. There was no stenosis. The mean time for the anastomoses once the learning curve was achieved was 32.7 min. After 21 anastomoses with RSS there was no improvement in the operating time. The quality of the suture was superior with RSS, with a larger anastomosis diameter, higher bursting pressure, and fewer suturing failures being found. The RSS suture withstood a higher traction force. The participants showed more discomfort suturing with CLI. CONCLUSION: This study demonstrated the feasibility of laparoscopic colorectal anastomosis using RSS. Anastomosis with RSS was shown to be safer. The three participants evaluating ergonomy reflected less discomfort in hand/wrist using RSS. Others ergonomic problems were comparable to CLI.

Precision in stitches: Radius Surgical System.

BACKGROUND: The Radius Surgical System is a manual manipulator with two additional degrees of freedom compared with conventional laparoscopic instruments (CLIs). This study aimed to compare the performance of laparoscopic suturing tasks with the use of the Radius Surgical System and CLIs, respectively. METHODS: Five experienced laparoscopic surgeons performed laparoscopic surgical tasks in a training box. The tasks consisted of knot-tying, suturing, and needle control tasks. The needle control task was performed to evaluate the precision of the needle drive by analysis of the needle exit point on a suture pad. In the knot-tying and suturing tasks, required time and accuracy value were measured. Needle control tasks were performed on three different angulations of plane. The angles between the instrument plane and the target plane (AIT) were 30 degrees, 60 degrees, and 90 degrees. The distance of the exit point to the center of the target field, the number of actions needed to fulfill a single task, and the required time were recorded and analyzed. RESULTS: In the knot-tying and frontal suturing tasks, there were no significant differences between the two groups. In the sagittal suturing task, the required time in the Radius group was significantly shorter than in the CLI group. In the needle control tasks on 30 degree and 60 degree AIT, the distance was significantly shorter in the Radius group than in the CLI group. There were no significant differences in the number of actions or the required time. In the frontal and sagittal needle control task on 90 degree AIT, the distance was significantly shorter in the Radius group than in the CLI group. The number of actions and the required time were significantly less in the Radius group than in the CLI group. CONCLUSIONS: The two additional degrees of freedom contributed to accurate and controlled needle guidance, especially in difficult spatial situations.

Ergonomics with the use of curved versus straight laparoscopic graspers during rectosigmoid resection: results of a multiprofile comparative study.

BACKGROUND: A detailed ergonomic comparison of motions and muscular activity in the left upper extremity using a laparoscopic straight or curved grasper in rectosigmoid resection is presented. METHODS: The study had two parts: experimental and clinical. In the experiment part, 30 laparoscopic sigmoid resections were performed under animal organ phantom conditions. The operations were divided into three groups according to instrument and trocar position. Group 1 (n = 10) underwent operations performed with a curved grasper in the excentral trocar position (in relation to the telescope trocar), with the left-hand curved grasper placed in the right flank and the right hand instrument in the right lower quadrant. In group 2 (n = 10), straight forceps were used in the excentral trocar position. Group 3 (n = 10) underwent laparoscopic sigmoid resection performed with a straight grasper in the central position (in relation to the telescope trocar), with the instruments placed at both sides of the lower abdomen. To measure ergonomic aspects during rectosigmoid resection, several overview video cameras, surface electromyography (EMG), an ultrasound tracking system (UTS), and a questionnaire were used. In the clinical part of the study, laparoscopic rectosigmoid resections (n = 5) were performed using a curved instrument in the excentral trocar position. The surgeon's left-hand movement and body posture were recorded for further analysis. RESULTS: The curved grasper required the fewest contractions (group 1) of the measured muscles. A comparison of the UTS analysis in the experimental part of the study and the video analysis in the clinical part showed economy of movements in group 1. According to subjective estimation, both physical activity and mental stress remain at the lowest level when the excentral trocar position is used (groups 1 and 2). CONCLUSIONS: The combination of the curved grasper and the excentral trocar position (in relation to the telescope trocar) is, according to our examinations, the best ergonomic adjustment for laparoscopic rectosigmoid surgery.

Experimental results of mesh fixation by a manual manipulator in a laparoscopic inguinal hernia repair model.

BACKGROUND: Laparoscopic mesh fixation using a stapler can lead to complications such as nerve injury and bowel injury. However, mesh fixation by suturing with conventional laparoscopic instruments (CLI) is difficult because of limited degrees of freedom. A manual manipulator--Radius Surgical System (Radius)--whose tip can deflect and rotate, gives the surgeon two additional degrees of freedom. The aim of this study is to evaluate the introduction of Radius to mesh fixation in laparoscopic inguinal hernia repair. METHODS: A model for inguinal hernia repair was prepared using animal organs in a trainer. Mesh fixation was performed using Radius, stapler, and CLI. Tensile strength during extraction of mesh toward the vertical direction, and execution time, were measured. RESULTS: The mean number of fixation points of Radius, stapler, and CLI was 9.3 +/- 1.5, 8.5 +/- 1.4, and 9.0 +/- 1.0, respectively. The mean tensile strength of fixation of mesh of Radius, stapler, and CLI was 140.7 +/- 48.9, 73.1 +/- 23.4, and 53.6 +/- 31.5 (N), respectively. The mean tensile strength per one fixation point by Radius, stapler, and CLI was 16.5 +/- 5.3, 8.7 +/- 2.8, and 6.3 +/- 3.6 (N), respectively. The mean execution time of Radius, stapler, and CLI was 479 +/- 108, 54 +/- 31, and 431 +/- 77 (sec), respectively. CONCLUSIONS: The mesh fixation by Radius was stronger than that by staples and CLI. Two additional degrees of freedom were useful in difficult angles. The introduction of Radius is feasible and facilitates the fixation of mesh with sutures in laparoscopic inguinal hernia repair.

Ringed silicon rubber attachment prevents laparoscopic surgeon's thumb.

BACKGROUND: This investigation, using the nerve conduction study, aimed to quantify the degree of laparoscopic surgeon's thumb, and to evaluate the effect of the ringed silicon rubber attachment (RSRA) developed by the authors. METHODS: For the study, 26 residents or students performed surgical tasks (grasping and dissecting) using both the laparoscopic forceps with RSRA and the conventional instrument. The paresthesia was evaluated with a severity score obtained by interview and measurement of sensory nerve conduction velocity (SCV). RESULTS: The mean severity score was 2.57 +/- 0.58 m/s for the conventional forceps and 1.05 +/- 0.80 m/s for the forceps with RSRA (p < 0.01). For the grasping task with the conventional forceps, the mean SCV was 58.3 +/- 2.81 m/s before and 54.8 +/- 2.83 m/s after the task (p < 0.01), whereas for the dissecting task, the corresponding values were 57.5 +/- 2.46 m/s and 56.1 +/- 2.93 m/s (p < 0.01). For the grasping task with the RSRA, the mean SCV was 57.1 +/- 3.33 m/s before and 55.9 +/- 3.18 m/s after the task (p < 0.01), whereas for the dissecting task, the corresponding values were 55.7 +/- 4.59 m/s and 55.8 +/- 3.50 m/s (nonsignificant difference). CONCLUSIONS: Laparoscopic surgeon's thumb was induced by compression of the lateral digital nerve. The RSRA significantly reduced the degree of paresthesia.

An innovative trainer for surgical procedures using animal organs.

Since 1990, almost 3000 surgeons have absolved the training course for minimally invasive surgery in our training center. A phantom trainer using animal organs has been used as a training device. Based on this experience, we have developed an innovative trainer for surgical procedures using animal organs. The form of this trainer was copied from a human body with gas insufflation; abdominal organs from the slaughterhouse can be integrated into this trainer. Surgeons can repeat operations such as laparoscopic cholecystectomy, appendectomy, fundoplication, colon resection and transanal endoscopic microsurgery in a realistic way and acquire a training effect in a short time.

Development of a new haemostatic dissecting forceps utilizing controlled heat as an energy source.

We tested a prototype of a new thermal surgical system in animal experiments. This device utilizes controlled heat as an energy source and seals and divides small- to medium-size vessels. The forceps we used in the current study are shaped like dissecting forceps used in conventional open surgery, and their grippers can open bilaterally. Heating elements are built into a gripper. The temperature adjustment is controlled by monitoring the electric resistance. Since the new device utilizes no ultrasonic energy, unfavorable phenomena such as cavitations or mist production are not observed. In a preliminary experiment, 12 segments of animal arteries were sealed and cut by the prototype forceps. Five artery stumps did not burst at the maximum pressure of the manometer system (1471 mmHg). The other seven stumps showed burst pressure ranging from 525 mmHg to 1051 mmHg. It is feasible to utilize controlled heat as a new alternative energy source for haemostatic surgical dissection. The new thermal dissector we are in the process of developing showed safe and quick sealing and cutting of the vessels in the experimental settings.

Larynx-preserving resection of the cervical esophagus for cervical esophageal carcinoma limited to the submucosal layer.

This report describes the surgical procedure consisting of larynx-preserving resection of the cervical esophagus and satisfactory lymphadenectomy. The sternum was split at the level of the 3rd intercostal space, which allowed an upper-mediastinal lymphadenectomy to be performed easily. The cervical esophagus was reconstructed using a free jejunal autograft. The stump of the thoracic esophagus and the caudad stump of the jejunal graft were anastomosed using a circular stapling instrument. The posterior part of the cephalad esophagojejunostomy was completed in two layers using the Lembert stitch. The wall of the cervical esophagus was opened to determine the oral cut line considering the safety margin from the carcinoma. After cervical esophagectomy was completed, suturing of the anterior wall was performed in one layer. The left cervical transverse artery and the internal jugular vein were employed for recipient vessels. This procedure is acceptable for high cervical esophageal carcinoma limited to the submucosal layer.