Intraoperative radiation therapy for pediatric sarcomas and other solid tumors.

PURPOSE: To evaluate local failure (LF) and toxicity after intraoperative radiation therapy (IORT) in pediatric solid tumors (ST). METHODS: A single-institution retrospective study of 96 pediatric patients (108 applications) with ST treated from 1995 to 2022 with IORT. LF was calculated via cumulative incidence function and overall survival (OS) by Kaplan-Meier method, both from the day of surgery. RESULTS: Median age at time of IORT was 8 years (range: 0.8-20.9 years). Median follow-up for all patients and surviving patients was 16 months and 3 years, respectively. The most common histologies included rhabdomyosarcoma (n = 42), Ewing sarcoma (n = 10), and Wilms tumor (n = 9). Most (95%) received chemotherapy, 37% had prior external beam radiation therapy to the site of IORT, and 46% had a prior surgery for tumor resection. About half (54%) were treated with upfront IORT to the primary tumor due to difficult circumstances such as very young age or challenging anatomy. The median IORT dose was 12 Gy (range: 4-18 Gy), and median area treated was 24 cm2 (range: 2-198 cm2). The cumulative incidence of LF was 17% at 2 years and 23% at 5 years. Toxicity from IORT was reasonable, with postoperative complications likely related to IORT seen in 15 (16%) patients. CONCLUSION: Our study represents the largest and most recent analysis of efficacy and safety of IORT in pediatric patients with ST. Less than one quarter of all patients failed locally with acceptable toxicities. Overall, IORT is an effective and safe technique to achieve local control in patients with challenging circumstances.

Evidence-based surgical guidelines for treating children with Wilms tumor in low-resource settings.

BACKGROUND: Survival of Wilms tumor (WT) is > 90% in high-resource settings but < 30% in low-resource settings. Adapting a standardized surgical approach to WT is challenging in low-resource settings, but a local control strategy is crucial to improving outcomes. OBJECTIVE: Provide resource-sensitive recommendations for the surgical management of WT. METHODS: We performed a systematic review of PubMed and EMBASE through July 7, 2020, and used the GRADE approach to assess evidence and recommendations. RECOMMENDATIONS: Initiation of treatment should be expedited, and surgery should be done in a high-volume setting. Cross-sectional imaging should be done to optimize preoperative planning. For patients with typical clinical features of WT, biopsy should not be done before chemotherapy, and neoadjuvant chemotherapy should precede surgical resection. Also, resection should include a large transperitoneal laparotomy, adequate lymph node sampling, and documentation of staging findings. For WT with tumor thrombus in the inferior vena cava, neoadjuvant chemotherapy should be given before en bloc resection of the tumor and thrombus and evaluation for viable tumor thrombus. For those with bilateral WT, neoadjuvant chemotherapy should be given for 6-12 weeks. Neither routine use of complex hilar control techniques during nephron-sparing surgery nor nephron-sparing resection for unilateral WT with a normal contralateral kidney is recommended. When indicated, postoperative radiotherapy should be administered within 14 days of surgery. Post-chemotherapy pulmonary oligometastasis should be resected when feasible, if local protocols allow omission of whole-lung irradiation in patients with nonanaplastic histology stage IV WT with pulmonary metastasis without evidence of extrapulmonary metastasis. CONCLUSION: We provide evidence-based recommendations for the surgical management of WT, considering the benefits/risks associated with limited-resource settings.

Social injustice symposium: Urban, rural, and global disparities in access to care.

BACKGROUND: Barriers in access to pediatric surgical care are common in low- and middle-income countries (LMICs), but also exist in high-income countries, particularly in urban and rural areas. METHODS: This article describes "Disparities in Access to Care"-held within the Social Injustice Symposium at the 2020 American Pediatric Surgical Association (APSA) Annual Meeting. RESULTS: This symposium outlined disparities in access to care, illustrated by examples from pediatric trauma and neonatal surgery in U.S. urban, U.S. rural, and non-U.S. global locations (LMICs). Geographic and financial challenges were common to families from the rural U.S. and LMICs. In contrast, families in U.S. urban settings generally do not face geographic barriers, but are often economically and racially diverse and many face complex societal factors leading to poor outcomes. Systemic processes must be changed to improve pediatric surgical health outcomes. CONCLUSION: A comprehensive health system with an equal emphasis on supportive care and surgery is required in all settings. Global collaboration and partnerships can provide an avenue for advocacy and strategic innovation to improve quality of care. LEVEL OF EVIDENCE: Ⅴ.

Late Complication of Congenital Diaphragmatic Hernia Repair: Recurrent Small Bowel Obstruction.

ABSTRACT: Congenital diaphragmatic hernia (CDH) is associated with high early mortality. However, advances in newborn care have led to improved survival into adolescence and early adulthood. We report a 17-year-old adolescent boy with recurrent small bowel obstruction after CDH repair at 2 days of age. Emergency physicians should be aware of late complications after neonatal CDH repair.

The first six years of the APSA Travel Fellowship Program: Impact and lessons learned.

INTRODUCTION: The American Pediatric Surgical Association (APSA) travel fellowship was established in 2013 to allow pediatric surgeons from low- and middle-income countries to attend the APSA annual meeting. Travel fellows also participated in various clinical and didactic learning experiences during their stay in North America. METHODS: Previous travel fellows completed a survey regarding their motivations for participation in the program, its impact on their practice in their home countries, and suggestions for improvement of the fellowship. RESULTS: Eleven surgeons participated in the travel fellowship and attended the annual APSA meetings in 2013-2018. The response rate for survey completion was 100%. Fellows originated from 9 countries and 3 continents and most fellows worked in government practice (n=8, 73%). Nine fellows (82%) spent >3 weeks participating in additional learning activities such as courses and clinical observerships. The most common reasons for participation were networking (n=11, 100%), learning different ways of providing care (n=10, 90.9%), new procedural techniques (n=9, 81.8%), exposure to a different medical culture (n=10, 90.9%), and engaging in research (n=8, 72.7%). Most of the fellows participated in a structured course: colorectal (n= 6, 55%), laparoscopy (n=2, 18%), oncology (n=2, 18%), leadership skills (n=1, 9%), and safety and quality initiatives (n=1, 9%). Many fellows participated in focused clinical mentorships: general pediatric surgery (n=9, 82%), oncology (n=5, 45%), colorectal (n=3, 27%), neonatal care (n=2, 18%) and laparoscopy (n=2, 18%). Upon return to their countries, fellows reported that they were able to improve a system within their hospital (n=7, 63%), expand their research efforts (n=6, 54%), or implement a quality improvement initiative (n=6, 54%). CONCLUSIONS: The APSA travel fellowship is a valuable resource for pediatric surgeons in low- and middle-income countries. After completion of these travel fellowships, the majority of these fellows have implemented important changes in their hospital's health systems, including research and quality initiatives, to improve pediatric surgical care in their home countries. LEVEL OF EVIDENCE: This is not a clinical study. Therefore, the table that lists levels of evidence for "treatment study", "prognosis study", "study of diagnostic test" and "cost effectiveness study" does not apply to this paper.

Bone Conduction Headphones for Force Feedback in Robotic Surgery.

Bone conduction headphones (Fig. 1) offer the unique ability to provide auditory information to the user without obstructing external sounds. We apply this technology to robotic surgery to provide the surgeon with force feedback information with minimal distraction. The device is evaluated by pairing it with a force sensor that is attached to a suture pad. Four participants were tasked to complete 25 sutures on the suture pad while either receiving no feedback or audio, visual, or combined feedback that represents the magnitude of their applied force. Trials performed with bone conducting headphones had noticeable improvements compared to previous trials without feedback, while the most noticeable improvements were observed for cases with both visual and auditory feedback. Auditory feedback may have an important role in a robotic surgery setting and bone conduction headphones may enable this form of feedback with minimal distraction.

Proof of Concept Study: Investigating Force Metrics of an Intracorporeal Suturing Knot Task.

BACKGROUND: Mastering proper force manipulation in minimally invasive surgery can take many hours of practice and training. Improper force control can lead to necrosis, infection, and scarring. A force-sensing skin (FSS) has been developed, which measures forces at the distal end of minimal access surgeries' (MAS) instruments without altering the instrument's structural integrity or the surgical workflow, and acts as a minimally disruptive add-on to any MAS instrument. METHODS: A proof of concept study was conducted using a FSS-equipped 5 mm straight-tip needle holder. Participants (n = 19: 3 novices, 11 fellows, and 5 staff surgeons) performed one intracorporeal suturing knot task (ISKT). Using participant task video footage, each participant's two puncture forces (each wall of the Penrose drain) and three knot tightening forces were measured. Force metrics from the three expertise groups were compared using analysis of variance (ANOVA) and Tukey's honest significance test with statistical significance assessed at P < .05. RESULTS: Preliminary ISKT force metric data showed differences between novices and more experienced fellows and surgeons. Of the five stages of the ISKT evaluated, the first puncture force of the Penrose drain seemed to best reflect the difference in skill among participants. The study demonstrated ISKT knot tightening and puncture force ranges across three expertise levels (novices, surgical fellows, and staff surgeons) of 0.586 to 6.089 newtons (N) and 0.852 to 2.915 N, respectively. CONCLUSION: The investigation of force metrics is important for the implementation of future force feedback systems as it can provide real-time information to surgeons in training and the operating theater.

A parent-science partnership to improve postsurgical pain management in young children: Co-development and usability testing of the Achy Penguin smartphone-based app.

BACKGROUND: Young children are at risk for poorly managed pain after surgery, with significant negative consequence to their quality of life and health outcomes. Mobile applications offer a highly accessible, engaging, and interactive medium to improve pain assessment and management; however, they generally lack scientific foundation or support. AIMS: The aims of this study were to describe a successful parent-science partnership in the development and testing of Achy Penguin, a parent-developed iOS app to help assess and manage acute pain in young children, and to evaluate and refine the usability of Achy Penguin in young children with acute postoperative pain. METHODS: Three cycles of iterative usability testing were conducted with 20 4- to 7-year-old children (M = 5.8 years) in hospital who had recently undergone surgery (n = 6-7 children/cycle). Semistructured qualitative interviews were analyzed using simple content analysis. RESULTS: Feedback from children and further integration of evidence-based pediatric pain knowledge led to refinements in app pain assessment and management content, as well as app flow and functionality. Changes improved children's ease of use and understanding and satisfaction by simplifying language in app instructions and content, adding audio and pictorial instructions, and increasing the engagement, interactiveness, immersiveness, and general appeal of pain management strategies. CONCLUSIONS: This article showcases the value of collaborative partnerships between various stakeholders (parents, app developers, and researcher/health care providers) to address gaps in pediatric pain care. The Achy Penguin app shows promise for improving pain assessment and management in young children, although further evaluation of app effectiveness and implementation is warranted.

Contexte: Les jeunes enfants sont à risque d'une mauvaise prise en charge de leur douleur après une chirurgie, ce qui entraîne des conséquences négatives sur leur qualité de vie et leurs issues de santé. Les applications mobiles sont un médium très accessible, convivial et interactif pour améliorer l'évaluation et la prise en charge de la douleur. Toutefois, elles n'ont généralement pas de soutien ou de fondements scientifiques.Buts: Décrire un partenariat parent-science réussi qui avait pour but de développer et de tester Achy Penguin, une application iOS développée avec l'aide des parents pour faciliter l'évaluation et la prise en charge de la douleur aigue chez les jeunes enfants, ainsi que pour évaluer et perfectionner la facilité d'utilisation de Achy Penguin chez les jeunes enfants souffrant de douleur postopératoire aiguë.Méthodes: Trois cycles itératifs de tests portant sur la facilité d'utilisation ont été menés auprès de 20 enfants âgés de quatre à sept ans (M = 5,8 ans) à l'hôpital qui avaient été soumis à une chirurgie récemment (n = 6 ­ 7 enfants/cycle). Des entrevues qualitatives semi-structurées ont été analysées à l'aide d'une analyse de contenu simple.Résultats: La rétroaction provenant des enfants et une plus grande intégration des connaissances en matière de douleur pédiatrique fondées sur des données probantes ont donné lieu à une amélioration du contenu sur l'évaluation et la prise en charge de la douleurConclusions: Cet article démontre la valeur des partenariats collaboratifs entre différentes parties prenantes (parents, développeurs d'applications, chercheurs et prestataires de soins de santé) afin de combler les lacunes existantes dans les soins pédiatriques pour traiter la douleur. L'application Achy Penguin est prometteuse pour améliorer l'évaluation et la prise en charge de la douleur chez les jeunes enfants, bien qu'une évaluation plus poussée de son efficacité et de sa mise en oeuvre soit nécessaire.

Extreme hepatic resections for the treatment of advanced hepatoblastoma: Are planned close margins an acceptable approach?

BACKGROUND: Orthotopic liver transplantation (OLT) is considered the standard for children with hepatoblastoma (HB) in whom complete surgical resection is not possible. However, OLT is not always available or feasible. OBJECTIVE: To describe the outcome of children with HB who were initially deemed unresectable and underwent complex hepatectomy with planned close margins, and ultimately avoided OLT. METHODS: Demographic data, surgical and pathologic details, and survival information were collected from children treated for HB between January 2010 to December 2015. RESULTS: Among six children (median age 12 months (3-41 months)), PRETEXT classification was III (n = 2), III/IV (n = 1), and IV (n = 3). Patients received a median of six cycles (range 4-7) of platinum-based induction chemotherapy; five received doxorubicin. Experienced pediatric surgeons performed extended right and left hepatectomy in five and one patients, respectively, with assistance of an experienced liver transplant surgeon (n = 4). Microscopic margins were positive (n = 2) and negative but close (n = 4; 2-5 mm). Two patients required vascular reconstruction of the vena cava. At median follow-up of 3.3 years (1.7-4.6 years), there was no evidence of local recurrence. One patient had recurrence of pulmonary disease 3 months after surgery. CONCLUSIONS: Patients with advanced HB treated with complex surgical resections with positive or close negative margins had good outcomes without OLT. We suggest that planned positive or close microscopic margins in highly selected HB patients may spare the morbidity of OLT and offer an alternative for those ineligible for OLT. Our experience illustrates the importance of a multidisciplinary team specialized in the management of liver tumors.

Expanding the Spectrum of Colonic Manifestations in Tuberous Sclerosis: L-Cell Neuroendocrine Tumor Arising in the Background of Rectal PEComa.

Tuberous sclerosis complex (TSC) is an autosomal dominant neurocutaneous condition that predisposes to numerous proliferative lesions, including perivascular epithelioid cell tumors (PEComas), such as lymphangioleiomyomatosis (LAM) and angiomyolipomas, and rare neuroendocrine neoplasms. We describe herein a TSC2-harboring tuberous sclerosis patient manifesting with a synchronous well-differentiated L-cell rectal neuroendocrine tumor and leiomyomatosis-like LAM of the rectum. The background large bowel wall was thickened by confluent nodular areas comprising vessels and spindle-to-epithelioid cells, which are immunoreactive for myoid (smooth muscle actin, muscle specific actin, and desmin) and melanocytic markers (HMB45, Melan-A, microphthalmia transcription factor, and CD117). With the exception of TSC-related pancreatic neuroendocrine tumors, the association between tuberous sclerosis and neuroendocrine neoplasms remains largely unknown in the gastrointestinal tract. Neuroendocrine tumorigenesis in tuberous sclerosis is often linked to inactivating mutations of TSC2 leading to aberrant activation of mammalian target of rapamycin (mTOR) pathway. In this report, we document, for the first time, two foci of L-cell rectal neuroendocrine tumor arising in the setting of tuberous sclerosis, thus broadening the spectrum of TSC-associated endocrine disorders. Moreover, to our knowledge, this is only the second documented case of gastrointestinal leiomyomatosis-like LAM in a patient with tuberous sclerosis. The current case provides further evidence that, similar to pancreatic neuroendocrine tumors, neuroendocrine tumors of the luminal gastrointestinal tract may also be a feature of tuberous sclerosis and can be seen in association with PEComas.

Novel force-sensing system for minimally invasive surgical instruments.

Mastering proper force manipulation in minimally invasive surgery can take many years. Improper force control can lead to necrosis, infection, and scarring. This paper describes a novel system to measure, log, and display external forces at the distal end of minimally invasive surgical instruments in real-time. The system, comprising of a Force- Sensing Sleeve, Bluetooth electronics module, and an Android mobile application. A sensorized 5 mm minimally invasive surgical needle holder was evaluated for bending force accuracy, linearity, and repeatability in six directions. The results showed that the system responded linearly to forces at the tool-tip independent of direction with an RMS error of 0.088 N. Repeatability was affected by system noise potentially arising from temperature drift and thermal noise. Future work will include characterization of communication performance for force feedback in surgical training and assessment.

Video assessment of laparoscopic skills by novices and experts: implications for surgical education.

BACKGROUND: Previous investigators have shown that novices are able to assess surgical skills as reliably as expert surgeons. The purpose of this study was to determine how novices and experts arrive at these graded scores when assessing laparoscopic skills and the potential implications this may have for surgical education. METHODS: Four novices and four general laparoscopic surgeons evaluated 59 videos of a suturing task using a 5-point scale. Average novice and expert evaluator scores for each video and the average number of times that scores were changed were compared. Intraclass correlation coefficients were used to determine inter-rater and test-retest reliability. Evaluators were asked to define the number of videos they needed to watch before they could confidently grade and to describe how they were able to distinguish between different levels of expertise. RESULTS: There were no significant differences in mean scores assigned by the two evaluator groups. Novices changed their scores more frequently compared to experts, but this did not reach statistical significance. There was excellent inter-rater reliability between the two groups (ICC = 0.91, CI 0.85-0.95) and good test-retest reliability (ICC > 0.83). On average, novices and experts reported that they needed to watch 13.8 ± 2.4 and 8.5 ± 2.5 videos, respectively, before they could confidently grade. Both groups also identified similar qualitative indicators (e.g., instrument control). CONCLUSION: Evaluators with varying levels of expertise can reliably grade performance of an intracorporeal suturing task. While novices were less confident in their grading, both groups were able to assign comparable scores and identify similar elements of a suturing skill as being important in terms of assessment.

Analysis of motion in laparoscopy: the deconstruction of an intra-corporeal suturing task.

BACKGROUND: This study analyzes instrument motion for segments of a defined intra-corporeal suturing task in a laparoscopic simulator. We describe a system providing real-time velocity and acceleration assessment in the performance of this task. Analysis of the deconstructed task segments allows targeted assessment and teaching. METHODS: A traditional box trainer was fitted with a custom-built motion-tracking system. Participants were stratified into novice, intermediate and expert groups. They performed a defined intra-corporeal suturing task. Real-time data were collected in four degrees of freedom (DOFs) (Roll, Surge, Pitch, Yaw). The task was then deconstructed into four segments: loading needle/pull-through, double-throw knot, first single-throw knot, and second single-throw knot. Motion analysis parameters (MAPs) were studied for each DOF. RESULTS: Sixty-four participants were tested (14 novices, 19 intermediates, 31 experts). The largest difference in MAPs was seen in the 'double-throw knot' segment. MAPs for the 'loading needle/pull-through' segment revealed differences between novices and experts in Roll and Pitch DOFs only. For the 'first single knot' segment, similar MAP trends were noted across all DOFs, with significant differences between novices versus experts and intermediates versus experts. For the 'second single knot' segment, the difference in MAPs was preserved only for novices versus experts. CONCLUSIONS: By analyzing motion for a defined suturing task in a laparoscopic simulator, we can gain insight into the specific hand motions distinguishing experts from non-experts. Such information may allow teaching in a more focused, effective and efficient manner.

Construct validity and reliability of a real-time multidimensional smartphone app to assess pain in children and adolescents with cancer.

We evaluated the construct validity (including responsiveness), reliability, and feasibility of the Pain Squad multidimensional smartphone-based pain assessment application (app) in children and adolescents with cancer, using 2 descriptive studies with repeated measures. Participants (8-18 years) undergoing cancer treatment were drawn from 4 pediatric cancer centers. In study 1, 92 participants self-reported their level of pain twice daily for 2 weeks using the Pain Squad app to assess app construct validity and reliability. In study 2, 14 participants recorded their level of pain twice a day for 1 week before and 2 weeks after cancer-related surgery to determine app responsiveness. Participants in both studies completed multiple measures to determine the construct validity and feasibility of the Pain Squad app. Correlations between average weekly pain ratings on the Pain Squad app and recalled least, average, and worst weekly pain were moderate to high (0.43-0.68). Correlations with health-related quality of life and pain coping (measured with PedsQL Inventory 4.0, PedsQL Cancer Module, and Pain Coping Questionnaire) were -0.46 to 0.29. The app showed excellent internal consistency (α = 0.96). Pain ratings changed because of surgery with large effect sizes between baseline and the first week postsurgery (>0.85) and small effect sizes between baseline and the second week postsurgery (0.13-0.32). These findings provide evidence of the construct validity, reliability, and feasibility of the Pain Squad app in children and adolescents with cancer. Use of real-time data capture approaches should be considered in future studies of childhood cancer pain. A video accompanying this abstract is available online as Supplemental Digital Content at http://links.lww.com/PAIN/A169.

Construct validity and educational role for motion analysis in a laparoscopic trainer.

BACKGROUND: Laparoscopic models for ex vivo up-skilling are becoming increasingly important components of surgical education. This study aims to establish the construct validity and possible educational role of a new laparoscopic box trainer equipped with a motion-tracking device. METHODS: A structured questionnaire was used to assign participants into novice, intermediate, or expert categories according to level of experience in minimal access surgery (MAS). Participants carried out a well-defined intracorporeal suturing task. Three specific motion analysis parameters (MAPs)-velocity, acceleration, and range-were measured and analyzed as movements in the four degrees of freedom available in traditional MAS using tracking sensors at the trocar insertion sites. RESULTS: The number of extreme velocity and acceleration events in all four degrees of freedom proved capable of differentiating between participants in the three categories of surgical experience using an ANOVA test (p < 0.001). Post hoc analysis confirmed these differences in the number of extreme velocity and acceleration events between all groups tested except for the velocity of the roll between the intermediates and experts. CONCLUSION: These findings confirm construct validity for this new laparoscopic box trainer system, which employs a novel analysis based on motion parameters. Motion parameters provide information regarding the overall smoothness of the operator's instrument handling, an important aspect of a surgeon's technique. This preliminary data will be used to design a simulator with real-time motion feedback to enhance its educational value.

Prospective evaluation of the impact of sonography on the management and surgical intervention of neonates with necrotizing enterocolitis.

BACKGROUND/AIM: Established indications for surgery in necrotizing enterocolitis (NEC) are pneumoperitoneum and failure to improve or clinical deterioration with medical treatment alone. It has been proposed that infants with intestinal necrosis may benefit from surgery in the absence of one of these indications yet the diagnosis of definitive intestinal necrosis is challenging. Recent data suggest that abdominal ultrasound (US) examination focused on the gastrointestinal tract and the peritoneal cavity may be of utility in this regard. The aim of this study was to evaluate the ability of abdominal US to detect intestinal necrosis in infants with radiographically confirmed NEC. METHODS: Twenty-six consecutive infants with Bell stage II or III NEC were prospectively included in the study between September 2013 and July 2014. Infants with a pre-existing indication for surgery were excluded. At least one abdominal US examination was performed in each patient using a standardized previously described method. Surgery was performed at the discretion of the attending surgeon based on clinical and imaging findings. Clinical, radiographic, US, and intra-operative data were recorded to allow comparison between US findings, surgical findings and outcome. RESULTS: US demonstrated signs of intestinal necrosis in 5 of the 26 patients. All of these five had laparotomy. Intestinal necrosis requiring resection was confirmed in four and the other was found to have NEC but no necrosis was identified. In 21 patients US did not suggest intestinal necrosis. Of these, only one had surgery in whom NEC but no necrosis was identified. The remaining 20 responded to medical treatment for NEC and were assumed not to have had intestinal necrosis based on improvement without surgical intervention. The sensitivity, specificity, positive predictive value and negative predictive values of US for the detection of bowel necrosis were calculated as 100, 95.4, 80.0, and 100%, respectively. CONCLUSION: Our prospective findings suggest that abdominal US can identify those infants with NEC who may need surgery by detecting bowel necrosis (prior to the development of perforation or medical deterioration) with high sensitivity and specificity. Early surgical intervention in the clinical pathway of NEC may lead to improved outcomes.

Motion analysis in the pediatric laparoscopic surgery (PLS) simulator: validation and potential use in teaching and assessing surgical skills.

BACKGROUND: Construct validity for the pediatric laparoscopic surgery (PLS) simulator has been established through a scoring system based on time and precision. We describe the development and initial validation of motion analysis to teach and assess skills related to pediatric minimal access surgery (MAS). METHODS: Participants were asked to perform a standardized intracorporeal suturing task. They were classified as novices, intermediates, and experts. Motion in the four degrees of freedom available during traditional MAS (PITCH, YAW, ROLL and SURGE) was assessed using range, velocity, and acceleration. RESULTS: Analysis of motion allowed discrimination between the 75 participants according to level of expertise. The most discriminating motion parameter was the acceleration in performing the ROLL (pronation/supination) with values of 30±27 for novices, 15±5 for intermediates, and 3.7±3 for experts (p<0.001). CONCLUSIONS: Tracking and analyzing the motion of instruments within the PLS simulator allow discrimination between novices, intermediates, and experts, thus establishing construct validity. Further development may establish motion analysis as a useful "real time" modality to teach and assess MAS skills.

Preoperative risk stratification of adnexal masses: can we predict the optimal surgical management?

STUDY OBJECTIVE: To characterize preoperative risk stratification with aim of identifying the accurate surgical approach of benign and malignant adnexal masses in pediatric patients. DESIGN: A retrospective chart review of all cases of adnexal masses surgically managed between January 2001 and December 2006. SETTING: The Hospital for Sick Children, Toronto, Canada. PARTICIPANTS: 129 cases of 126 pediatric and adolescent patients who underwent operative management of their adnexal masses. MAIN OUTCOME MEASURES: Ultrasonographic characteristics (cyst size and character), surgical approach (laparoscopy vs laparotomy) and method of cyst removal (cystectomy vs oophorectomy). Data was assessed with a Fisher Exact test where appropriate (P < .05). RESULTS: Malignancies were more frequently treated by laparotomy (n = 14, 98.6%, P < .001), and benign cases by laparoscopy (n = 78, 97%, P < .001). On ultrasonography, malignant masses were more often complex (n = 16, 100%, P = .006) and ≥8 cm (n = 16, 100%, P < .001) than benign masses (≥8 cm n = 60, 53%, complex n = 76, 67%). Combining ultrasonographic measurements of ≥8 cm and complexity identified 100% of malignant masses (n = 16) and 36% of benign masses (n = 41, P < .001, PPV = 37.1, NPV = 100%). Additional imaging including CT/MRI was ordered by pediatric surgeons (n = 17, 77%) more often than pediatric gynecologists (n = 44, 41%, P = .002). Furthermore, pediatric surgeons managed adnexal masses by oophorectomy (n = 12, 55%) more often as compared to pediatric gynecologists (n = 19, 18%, P < .001). CONCLUSION: Using preoperative characteristics of complexity and ≥8 cm reduces the number of benign masses treated with laparotomy while ensuring malignant masses are managed with an open approach.