Curva de aprendizaje para el acceso con trocar óptico en cirugía pélvica laparoscópica: estudio prospectivo / Learning curve of optical trocar access during laparoscopic pelvic surgery: A prospective study

Introducción El acceso con trocar óptico (ATO) es una técnica modificada de laparoscopia cerrada cuyo objetivo es minimizar el riesgo de lesiones vasculares o intestinales y reducir la posible fuga de gas. Se ha analizado el efecto de la curva de aprendizaje (CA) para el ATO, considerando n=30 procedimientos como umbral para definir un nivel aceptable de experticia. Nuestro objetivo es evaluar el impacto de la CA en los primeros 30 casos de ATO realizados por un aprendiz. Métodos Se trata de un estudio prospectivo aleatorizado en 60 pacientes planificadas para cirugía ginecológica laparoscópica. Las pacientes fueron seleccionadas aleatoriamente para el ATO realizado por un cirujano sin entrenamiento previo en la técnica o por un cirujano experto. La CA se evaluó mediante: 1) tiempo hasta lograr el acceso; 2) número de correcciones hechas por el experto; 3) número de veces en que la punta del trocar se detuvo en la capa preperitoneal; 4) errores al realizar la incisión en la piel; 5) veces en que la punta del trocar termina bajo el epiplón; 6) complicaciones. Para analizar el CA en los 30 primeros casos, se estratificaron los procedimientos en 3 grupos (casos 1-10; 11-20; 21-30) tanto para el aprendiz como para el experto y se compararon las variables de la CA. Resultados De forma global, el tiempo medio de inserción para el ATO fue de 56s. No se registraron complicaciones intraoperatorias ni postoperatorias graves. El tiempo medio de inserción fue estadísticamente más largo para el aprendiz en comparación con el experto en los 10 primeros casos (91s frente a 33s, respectivamente, p=0,01). En los casos 11-20 y 21-30, la ventaja de tiempo del cirujano experto se hizo menos evidente (p=0,05). El número de veces que la punta del trocar se detuvo en la capa preperitoneal fue similar entre los grupos, así como las veces que la punta del trocar llegó por debajo del epiplón. Conclusiones La técnica de ATO es rápida y reproducible . ... (AU)

Introduction The optical trocar access (OTA) is a modified closed technique that aims to minimize the risk of vascular or bowel injuries while reducing the likelihood of gas leakage. A learning curve (LC) effect for OTA has been invoked with n=30 procedures being considered as a threshold to define expertise. We aim to evaluate the impact of the LC within the first thirty cases of OTA performed by a trainee. Methods This is a prospective randomized study on 60 patients elected to laparoscopic gynecological surgery. Patients were randomized to have OTA insertion by a junior surgeon or by an expert. LC was evaluated by: 1) insertion time; number of: 2) corrections by the senior; 3) times the tip of the trocar stopped in the preperitoneal layer; 4) mistakes of skin incision; 5) times the tip of the trocar ends under the omentum; 6) complications. To analyze the LC within the first 30 cases, procedures were stratified in 3 groups (cases 1-10; 11-20; 21-30) for both trainee and expert and LC variables were compared. Results Overall, mean OTA insertion time was 56s. No major intra- and post-operative complications were recorded. Mean insertion time was statistically significantly longer for the trainee compared to the expert within the first 10 cases (91 vs 33s respectively, p=0.01). For cases 11-20 and 21-30, time advantage of the senior surgeon is less evident (p=0.05). The number of times the tip of the trocar stopped in the preperitoneal layer was similar between groups, as well as times the tip of the trocar ends under the omentum. Conclusions OTA is a fast and simple way to achieve the pneumoperitoneum and first trocar insertion as a single step. The current series confirms the effectiveness of the technique since the beginning of the LC. (AU)

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.

Laparoscopic renal surgery using multi degree-of-freedom articulating laparoscopic instruments in a porcine model.

PURPOSE: We evaluated the performance of a new multi-degree-of-freedom articulating laparoscopic instrument, ArtiSential, and compared it with that of a straight-shaped instrument and the da Vinci surgical system, in renal surgery using porcine model. MATERIALS AND METHODS: Nine female Yorkshire pigs were equally divided into three groups. The three groups were compared at each surgical step in terms of objective and subjective parameters. RESULTS: The median operative times for renal pedicle clamping and ureter dissection were significantly shorter in ArtiSential group than robotic group (1.3 min vs. 4.7 min, p=0.002; 8.1 min vs. 11.1 min, p=0.015). The median operative time for bladder repair was significantly longer in ArtiSential group than robotic and straight-shaped groups (17.9 min vs. 5.5 min, p=0.002; 17.9 min vs. 9.3 min, p=0.026). There were no significant differences among groups in terms of blood loss or intraoperative complications. ArtiSential device was less useable for renorrhaphy (p=0.009) and bladder repair (p=0.002) compared to the robotic system. ArtiSential group was less accurate than robotic group in terms of tumor resection, renorrhaphy, and bladder repair. During ureter dissection, bladder cuff excision, and bladder repair, the surgeon experienced greater wrist discomfort but lesser back discomfort in ArtiSential group than robotic group. CONCLUSIONS: For most steps, ArtiSential performed as well as robotic and straight-shaped instruments. The development of specialized surgical techniques for ArtiSential will maximize the advantages of these instruments.

Distribution of surgical smoke particles within a simulated laparoscopic cavity utilizing an AirSeal® system.

An exploratory study was performed to determine the distribution of surgical smoke particulate matter (SSPM) and evacuation times within an AirSeal® System and a traditional insufflation access system in various simulated surgical scenarios. Identified trends showed statistical significance when setting the AirSeal® System to Low smoke evacuation that it reduces the percentage of particulate matter at the Access Port opening. Additionally, it was observed that when utilising a laparoscopic tool a similar trend in particle distributions were seen between either insufflation and access system at the opening of the Access Port and trocar. Evacuation times for SSPM removal within the AirSeal® System showed an overall average to ≥95% reduction of 5.64 min within the surgical cavity, 3.69 min at the Access Port opening, and 3.61 min within the smoke evacuation line. The overall average for the traditional insufflation and access system was 9.38 min within the surgical cavity and 6.06 min at the trocar opening. Results showed that when using the traditional system compared to the AirSeal® System, it resulted in a percent change increase in evacuation times of 66.31% within the surgical cavity and 64.23% at the trocar opening.

Effects of oxycodone hydrochloride and dezocine on hemodynamics and levels of inflammatory factors in patients receiving gynecological laparoscopic surgery under general anesthesia

Abstract We aimed to compare the effects of oxycodone hydrochloride and dezocine on hemodynamics and inflammatory factors in patients receiving gynecological laparoscopic surgery under general anesthesia. A total of 246 patients were divided into group A and B (n=123). Hemorheology indices were recorded 5 min after anesthesia (T0), 1 min after pneumoperitoneum (T1), when position was changed 5 min after pneumoperitoneum (T2), 15 min after pneumoperitoneum (T3), 1 min (T4) and 5 min (T5) after position was restored. Visual analogue scale scores 1, 2, 6, 12, 24 and 48 h after operation were recorded. Postoperative adverse reactions and visceral pain were observed. The expression levels of inflammatory factors were detected by enzyme-linked immunosorbent assay 12 h after operation. Compared with group A, group B had higher heart rate and mean arterial pressure at T2, lower central venous pressure and cardiac output at T1-T3, and higher systemic vascular resistance at T1-T5 (P<0.05). The incidence rate of pain syndrome in group A was lower (P<0.05). Group A had lower tumor necrosis factor-alpha and interleukin-6 expression levels and higher interleukin-10 level than those of group B (P<0.05). For gynecological laparoscopic surgery, oxycodone preemptive analgesia has superior outcomes to those of dezocine

Procedimiento de malone videoasistido en pediatria: primeros dos casos en Uruguay / Laparoscopic malone procedure in pediatrics: first cases in Uruguay / Procedimento de malone videoassistido em pediatria: dois primeiros casos no Uruguai

El procedimiento de apendicostomía continente para la realización de enemas anterógrados ha sido publicado ya hace varios años para el tratamiento de la incontinencia fecal y del estreñimiento de muy difícil manejo. Otra indicación del mismo incluye el estreñimiento severo, en el cual se agotaron las medidas farmacológicas y el único tratamiento efectivo es la realización de enemas. El objetivo principal del procedimiento es ofrecer a los niños y sus familias una alternativa a la hora de realizar los enemas, logrando una mayor adherencia al tratamiento y buscando alcanzar una mejor calidad de vida que permita adecuarse a las actividades con sus pares. Por otra parte permite al niño ir logrando cierta independencia gradual a medida que crezca, preparándolos para el futuro y haciéndolos participes activos de su cuidado. Se describen los primeros casos en donde utilizamos en nuestro medio el abordaje laparoscópico, sus indicaciones, la técnica quirúrgica y los resultados iniciales. Hemos constatado como ventaja principal los beneficios del abordaje mínimamente invasivo, como la exploración completa de la cavidad abdominal, el menor dolor postoperatorio, cicatrices más pequeñas, menor creación de adherencias.

The appendicostomy procedure for performing antegrade enemas has been published several years ago for the treatment of fecal incontinence and constipation that are very difficult to manage. The Malone procedure is performed in our setting, especially in patients with fecal incontinence secondary to neurological disorders such as myelomeningocele using a conventional approach. Other indications of it is severe constipation, in which pharmacological measures have been exhausted and the only effective treatment is enemas. The main objective of the procedure is to offer children and their families an alternative when performing enemas, achieving greater adherence to treatment and seeking to achieve a better quality of life that allows them to adapt to the activities of their peers. On the other hand, it allows the child to achieve a certain gradual independence as they grow, preparing them for the future and making them active participants in their care. The first cases in which we use the laparoscopic approach, its indications, the surgical technique and the initial results are described. We think that its main advantage is the benefits of the minimally invasive approach, such as complete exploration of the abdominal cavity, less postoperative pain, smaller scars, and less creation of adhesions.

O procedimento de apendicostomia continente para a realização de enemas anterógrados foi publicado há vários anos para o tratamento de incontinência fecal e constipação de difícil manejo. Outra indicação inclui constipação grave, na qual as medidas farmacológicas foram esgotadas e o único tratamento eficaz são os enemas. O principal objetivo do procedimento é oferecer às crianças e seus familiares uma alternativa na realização dos enemas, alcançando maior adesão ao tratamento e buscando alcançar uma melhor qualidade de vida que lhes permita adaptar-se às atividades com seus pares. Por outro lado, permite que a criança alcance uma certa independência gradual à medida que cresce, preparando-a para o futuro e tornando-a participante ativa em seus cuidados. São descritos os primeiros casos em que utilizamos a via laparoscópica, suas indicações, a técnica cirúrgica e os resultados iniciais. Confirmamos os benefícios da abordagem minimamente invasiva como principal vantagem, como exploração completa da cavidade abdominal, menos dor pós-operatória, cicatrizes menores e menor formação de aderências.

Stiffness Assessment and Lump Detection in Minimally Invasive Surgery Using In-House Developed Smart Laparoscopic Forceps.

Minimally invasive surgery (MIS) incorporates surgical instruments through small incisions to perform procedures. Despite the potential advantages of MIS, the lack of tactile sensation and haptic feedback due to the indirect contact between the surgeon's hands and the tissues restricts sensing the strength of applied forces or obtaining information about the biomechanical properties of tissues under operation. Accordingly, there is a crucial need for intelligent systems to provide an artificial tactile sensation to MIS surgeons and trainees. This study evaluates the potential of our proposed real-time grasping forces and deformation angles feedback to assist surgeons in detecting tissues' stiffness. A prototype was developed using a standard laparoscopic grasper integrated with a force-sensitive resistor on one grasping jaw and a tunneling magneto-resistor on the handle's joint to measure the grasping force and the jaws' opening angle, respectively. The sensors' data are analyzed using a microcontroller, and the output is displayed on a small screen and saved to a log file. This integrated system was evaluated by running multiple grasp-release tests using both elastomeric and biological tissue samples, in which the average force-to-angle-change ratio precisely resembled the stiffness of grasped samples. Another feature is the detection of hidden lumps by palpation, looking for sudden variations in the measured stiffness. In experiments, the real-time grasping feedback helped enhance the surgeons' sorting accuracy of testing models based on their stiffness. The developed tool demonstrated a great potential for low-cost tactile sensing in MIS procedures, with room for future improvements. Significance: The proposed method can contribute to MIS by assessing stiffness, detecting hidden lumps, preventing excessive forces during operation, and reducing the learning curve for trainees.

Autonomous robotic laparoscopic surgery for intestinal anastomosis.

Autonomous robotic surgery has the potential to provide efficacy, safety, and consistency independent of individual surgeon's skill and experience. Autonomous anastomosis is a challenging soft-tissue surgery task because it requires intricate imaging, tissue tracking, and surgical planning techniques, as well as a precise execution via highly adaptable control strategies often in unstructured and deformable environments. In the laparoscopic setting, such surgeries are even more challenging because of the need for high maneuverability and repeatability under motion and vision constraints. Here we describe an enhanced autonomous strategy for laparoscopic soft tissue surgery and demonstrate robotic laparoscopic small bowel anastomosis in phantom and in vivo intestinal tissues. This enhanced autonomous strategy allows the operator to select among autonomously generated surgical plans and the robot executes a wide range of tasks independently. We then use our enhanced autonomous strategy to perform in vivo autonomous robotic laparoscopic surgery for intestinal anastomosis on porcine models over a 1-week survival period. We compared the anastomosis quality criteria-including needle placement corrections, suture spacing, suture bite size, completion time, lumen patency, and leak pressure-of the developed autonomous system, manual laparoscopic surgery, and robot-assisted surgery (RAS). Data from a phantom model indicate that our system outperforms expert surgeons' manual technique and RAS technique in terms of consistency and accuracy. This was also replicated in the in vivo model. These results demonstrate that surgical robots exhibiting high levels of autonomy have the potential to improve consistency, patient outcomes, and access to a standard surgical technique.

Non-invasive laparoscopic detection of small tumors of the digestive tract using inductive sensors of proximity.

The precise location of gastric and colorectal tumors is of paramount importance for the oncological surgeon as it dictates the limits of resection and the extent of lymphadenectomy. However, this task proves sometimes to be very challenging, especially in the laparoscopic setting when the tumors are small, have a soft texture, and do not invade the serosa. In this view, our research team has developed a new instrument adapted to minimally-invasive surgery, and manipulated solely by the operating surgeon which has the potential to locate precisely tumors of the digestive tract. It consists of an inductive proximity sensor and an electronic block encapsulated into an autoclavable stainless-steel cage that works in tandem with an endoscopic hemostatic clip whose structure was modified to increase detectability. By scanning the serosal side of the colon or stomach, the instrument is capable to accurately pinpoint the location of the clip placed previously during diagnostic endoscopy on the normal bowel mucosa, adjacent to the tumor. In the current in-vivo experiments performed on large animals, the modified clips were transported without difficulties to the point of interest and attached to the mucosa of the bowel. Using a laparoscopic approach, the detection rate of this system reached 65% when the sensor scanned the bowel at a speed of 0.3 cm/s, and applying slight pressure on the serosa. This value increased to 95% when the sensor was guided directly on the point of clip attachment. The detection rate dropped sharply when the scanning speed exceeded 1 cm/s and when the sensor-clip distance exceeded the cut-off value of 3 mm. In conclusion, the proposed detection system demonstrated its potential to offer a swift and convenient solution for the digestive laparoscopic surgeons, however its detection range still needs to be improved to render it useful for the clinical setting.

New device with force sensors for laparoscopic liver resection - investigation of grip force and histological damage.

INTRODUCTION: As the benefits of minimally invasive surgery are recognized, the rate of laparoscopic liver resection (LLR) is rapidly increasing. Liver tissue is fragile compared to tissue of the stomach and colon. In endoscopic and robotic surgery, sufficient tactile sensation is yet to be obtained. Therefore, it is necessary to measure and indicate the grip force of forceps during surgery. We developed a new device consisting of force sensors and investigated its grip force and the resulting histological damage to liver tissue. MATERIAL AND METHODS: We measured the grip force generated during laparoscopic surgery in pigs using the forceps with pressure sensors developed by us. Throughout the hepatectomy, we measured the grip force generated by the forceps in real time. We investigated the histological damage to the liver caused by using the forceps with different grip forces. RESULTS: The subject produced a mean grip force of 1.75 N during the procedures. The maximum grip force was 3.38 N. By grasping the tissues of the liver with forceps, bleeding and destruction of the hepatic lobules were observed in a manner dependent on increasing grip force. CONCLUSION: The new device is necessary for preventing liver damage in laparoscopic hepatic resection.

Are the relative benefits of open versus laparoscopic intraperitoneal mesh repair of umbilical hernias dependent on the diameter of the defect?

BACKGROUND: The aim of this study was to assess whether the respective values of open and laparoscopic intraperitoneal repairs of umbilical hernias are related to the European Hernia Society diameter of defects. METHODS: This registry-based study compared the early and 2-year outcomes of 776 open versus 1,019 consecutive laparoscopic intraperitoneal repairs performed from 2011 to 2019. RESULTS: Intraperitoneal mesh repair, either laparoscopic or open, was found to be a safe procedure at the 2-year follow-up. The incidence of reoperated bowel obstructions was 0.3%. Compared with the open group: (1) postoperative surgical site occurrences in small (<2 cm) or medium (2-4 cm) hernias (0.3% vs 2.4%; P = .041; 1.4% vs 5.9%; P = .0002); (2) recurrence rates in large (≥4 cm) umbilical hernias (0.0% vs 8.6%; P = .0195); and (3) cumulative reoperation rates (0.9% vs 2.2%; P = .021) were significantly better in the laparoscopic group. Conversely, the rate of early pain on day 1 and 1 month postsurgery was higher in the laparoscopic group, for all hernia sizes (P < .001). The rate of moderate or severe chronic pain at 2 years was significantly higher in the laparoscopic group (8.1% vs 2.4%; P = .049) for small hernias. CONCLUSION: The respective benefit to drawback ratios for open versus laparoscopic intraperitoneal repairs were related to the European Hernia Society diameter of hernia defect. In medium-large hernias, the benefits of laparoscopic repair overrode its drawbacks. In small hernias, the low recurrence rate, reduced early and chronic pain, and better rate of ambulatory surgery suggest there is still a place for open repair.

Camera realignment imposes a cost on laparoscopic performance.

There is an unresolved question about whether realigned visual feedback is beneficial or costly to laparoscopic task performance. We provide evidence that camera realignment imposes a reliable cost on performance across both naive controls and experienced surgeons. This finding clarifies an important ongoing discussion in the literature about the effects of camera realignment, which could inform the strategies that laparoscopic surgeons use in the operating room.

Comparison of a single-access glove port with a SILS™ port in a surgical simulator model using MISTELS.

BACKGROUND: Recent advances in laparoscopy both in human and veterinary medicine have looked at means of being less invasive by using single-port access surgery as opposed to multiport access surgery. The glove port has gained popularity as a cost-effective alternative to commercially available single-port access devices. The primary aim of this study was to compare the glove port to the SILS™ port in a simulator model using the first two MISTELS (McGill inanimate system for training and evaluation of laparoscopic skills) tasks (peg transfer and pattern cutting). METHODS: Twenty-two novices were enrolled in this experimental study. Each participant had 60 min to practise both MISTELS tasks using two-port laparoscopy. Thereafter participants performed both tasks using the glove and SILS™ port with scores being calculated based on task completion time and errors. Higher scores were indicative of better performance. Participants were assigned into two groups with the starting order of the single ports being randomly selected. A self-evaluation questionnaire with three questions was completed by each participant after testing, rating each port. RESULTS: Significantly (p < 0.05) higher scores were achieved using the glove port compared to the SILS™ port when performing both tasks. The glove port was subjectively evaluated as easier to use with more manoeuvrability of the instruments than the SILS™ port. IMPLICATIONS OF THE STUDY: The glove port's improved manoeuvrability and ease of use make it a cost-effective alternative to the SILS™ port, for use in single-port laparoscopic veterinary surgery.

Effectiveness of Articulating Linear Stapler for Total and Partial Laparoscopic Splenectomy in Children.

Purpose: We performed a retrospective study to determine the effectiveness and feasibility of articulating linear stapler in laparoscopic total splenectomy (LTS) and laparoscopic partial splenectomy (LPS), focusing on technical laparoscopic skills that could help pediatric surgeons to avoid intra- and postoperative complications. Methods: Retrospective cohort study of children younger than 18 years who underwent laparoscopic spleen surgery between January 2008 and March 2020. Age, sex, indication for surgery, operative time (OT), intra- and postoperative complications, and postoperative length of hospital stay (LHS) were analyzed. Data from parenchymal resection and vessels sealing techniques were obtained. Results: Thirty patients, 19 LTS and 11 LPS, were included. The mean age of the patients was 10.9 years, and 16 patients were male and 14 were female. For hematologic diseases, LTS was the elective surgery, associated with cholecystectomy in 5 cases. LPS was the common procedure for splenic cysts. The stapler was used in LTS to close the hilum vessels and in LPS for parenchymal resection. No statistically significant differences in OT were observed comparing LTS and LPS. Two conversions occurred in LTS; none in LPS. The mean LHS was 6 days in both groups. No recurrence or major complications appeared in both groups at 1-12 years of follow-up. In particular for LPS, there are no relapse of cyst neither reduction in splenic function. Conclusions: This study shows the effectiveness, feasibility, and safety of mechanic stapler in splenic surgery both for hilum vessels sealing and for parenchymal resection. The use of this device can reduce risk of hemorrhagic recurrences or major surgical complications improving the safety of the operation.

Prolapse Surgery: What Kind of Antibiotic Prophylaxis Is Necessary?

INTRODUCTION: The aim of this study was to assess whether antibiotic prophylaxis or therapy is sufficient for laparoscopic or vaginal prolapse surgery with mesh. METHODS: This is a single-center prospective study. The study was divided into 3 groups. Protocol A: metronidazole (15 mg/kg) and piperacillin-tazobactam (2 g) 1 h before surgery and, for postoperative treatment, gentamycin (160 mg) 1 h before surgery in a single dose. Metronidazole and piperacillin-tazobactam were administered until hospital discharge. Protocol B: gentamycin and piperacillin-tazobactam in the same manner as group A. Protocol C: clindamycin (600 mg) and gentamicin (160 mg) 1 h before surgery in a single dose. RESULTS: We included 87 consecutive patients who underwent prolapse surgery involving mesh prostheses: 57 by the laparoscopic approach and 30 by the vaginal route. Of these, 30 patients were included in protocol A, 30 in protocol B, and 27 in protocol C. There were no statistically significant differences among the 3 protocols regarding any postoperative complications, except for urinary tract infections that were more in the vaginal approach than in the laparoscopic route, in protocol A (p = 0.002). CONCLUSIONS: One-shot prophylaxis can be successfully used in prolapse surgery regardless of the surgical approach.

Comparison of intraoperative and short-term postoperative outcomes between robot-assisted laparoscopic multi-port pyeloplasty using the da Vinci Si system and single-port pyeloplasty using the da Vinci SP system in children.

PURPOSE: We compared the intraoperative and postoperative outcomes of single-port robot-assisted laparoscopic pyeloplasty (S-RALP) using the da Vinci SP® system and conventional multi-port robot-assisted laparoscopic pyeloplasty (M-RALP) in pediatric patients. MATERIALS AND METHODS: Multi-port and single-port pyeloplasty have been performed in pediatric patients in our institution since October 2015 and February 2019, respectively. We conducted an entire cohort comparison. Considering the learning curve of M-RALP, we defined the last 15 cases of M-RALP as a subgroup of M-RALP and compared this subgroup with the entire cohort of S-RALP patients. RESULTS: Thirty-one patients who underwent multi-port pyeloplasty and 15 patients who underwent single-port pyeloplasty were enrolled in this study. Age, height, body weight, laterality, surgical indication, and ipsilateral differential renal function were statistically similar in the M-RALP and S-RALP groups. The median operative time (3.0 h vs. 2.4 h; p=0.01) and the median console time (2.2 h vs. 1.5 h; p<0.001) were longer in the M-RALP group than in the S-RALP group. There was no significant difference in operative time or console time between the M-RALP subgroup and the S-RALP group. There were no significant differences in the length of hospitalization, pain score, morphine-equivalent use of analgesics, or postoperative differential renal function in all comparisons. CONCLUSIONS: This study confirmed that pyeloplasty using the da Vinci® SP system can be started by robotic surgeons who can overcome the learning curve. Robot-assisted laparoscopic single-port pyeloplasty is feasible in noninfant pediatric patients.