Successful endoscopic approach for peripheral neuroblastic tumors in children.

BACKGROUND: Recently, reports of endoscopic approaches for neuroblastoma, ganglioneuroblastoma, and ganglioneuroma (peripheral neuroblastic tumor; PNTs) have been increasing. This study aimed to clarify the indications for endoscopic surgery for PNTs. METHODS: Pediatric patients who underwent endoscopic surgery for PNTs at our institution were included in this study. Image-defined risk factors (IDRFs) were analyzed using preoperative computed tomography (CT). RESULTS: Twenty-four patients underwent endoscopic surgery for PNTs. The diagnoses included neuroblastoma (n = 11), ganglioneuroma (n = 10), and ganglioneuroblastoma (n = 3). Regarding the tumor site, there were 18 cases of adrenal tumors, five cases of mediastinal tumors, and one case of retroperitoneal tumors. Image-defined risk factors were positive in eight cases (contacted with a renal vessel, n = 6; compression of principal bronchi, n = 2). Complete resection was accomplished in 21 cases (14 of 16 IDRF-negative cases and seven of eight IDRF-positive cases). All patients survived without recurrence during the follow-up period. CONCLUSIONS: The CT findings of contact with renal vessels and compression of principal bronchi do not seem to be indicators of incomplete resection. An endoscopic approach to PNTs in pediatric patients is feasible with a good prognosis if patients are selected strictly.

Surgical outcome and prognosis of pediatric solid-pseudopapillary neoplasm.

BACKGROUND: The aim of this study was to clarify the characteristics and outcomes of pediatric patients with solid pseudopapillary neoplasms (SPNs) who underwent pancreatectomy. METHODS: Pediatric patients with SPNs who underwent pancreatectomy at our institution between 1995 and 2020 were included in the study. RESULTS: During the period under review, 12 patients underwent pancreatectomy for SPNs (median age: 10 years; range: 6-15 years). The surgical procedures included pancreatoduodenectomy (n = 2; 16.6%), distal pancreatectomy (n = 3; 25%), and enucleation (n = 7; 58.3%). The most common postoperative complication was postoperative pancreatic fistula (n = 6; 50%). Patients who underwent enucleation tended to have higher postoperative complication rates compared with those who underwent other procedures. All patients were alive without recurrence at the end of the study period. CONCLUSIONS: SPN is associated with a good prognosis, regardless of the surgical procedure. If surgeons select enucleation for pediatric SPNs, they should bear in mind that it is associated with a higher complication rate.

Laparoscopic approach for abdominal neuroblastoma in Japan: results from nationwide multicenter survey.

BACKGROUND: Some neuroblastoma (NB) cases are suitable for minimally invasive surgery (MIS), but indication and technical issue are unclear. We assessed the current status of MIS for abdominal NB after mass screening period in Japan. METHODS: Preliminary questionnaires requesting the numbers of NB cases that underwent MIS from 2004 to 2016 were sent to 159 Japanese institutes of pediatric surgery. The secondary questionnaires were then sent to the institutions that reported MIS cases of NB in order to collect detailed data. RESULTS: One hundred and thirty-four (84.2%) institutions responded to the preliminary questionnaires, and 83 (52.2%) reported managing operative cases. The total number of operative cases was 1496. MIS was performed for 175 (11.6%) cases, of which the completed forms of 140 patients were returned, including 100 abdominal NB cases. The male/female ratio was 51/49. Forty-seven cases underwent a laparoscopic biopsy, and 2 (4.3%) cases were converted to laparotomy due to bleeding. Sixty-five cases underwent MIS for radical resection, and 7 (10.8%) were converted to laparotomy. The reasons for open conversion were bleeding and severe adhesion. Regarding open conversion, there were no significant relationships between conversion and neo-adjuvant chemotherapy, biopsies, stage, size, or MYCN amplification. We found no relationship between resectability and vascular encasement in this study. There was relationship between the resected tumor size and the patients' height, which was expressed using the following formula: [Formula: see text] (x, patients height, y, tumor size; p = 0.004219, SE: 1.55566). Postoperative complications after radical resection were recognized in 7 (10.8%) cases. CONCLUSIONS: MIS was performed in limited cases of abdominal NB. A laparoscopic biopsy with careful attention to bleeding is feasible. The resected tumor size was shown to correlate with the patients' height. Tumor size within 6 cm of maximum diameter can be resected safely.

Effects of changes in skeletal muscle mass on the prognosis of pediatric malignant solid tumors.

PURPOSE: This study aims to clarify the relationship between changes in skeletal muscle mass during treatment and prognosis of pediatric malignant solid tumors. METHODS: Patients with pediatric malignant solid tumors who were treated at Kyushu University Hospital from 2007 to 2017 were divided into two groups: the progression-free survival (PFS) group and the relapse/death (R/D) group; the psoas major muscle volume (PMV) was then compared. We also measured the PMV and psoas muscle area (PMA) of pediatric patients with no complications who underwent surgery for acute appendicitis (control) and compared the values with those of patients with malignant tumors. RESULTS: No significant differences were observed in the PMV and PMA between patients with appendicitis and those with malignant tumors. Significant differences were found in the rate of change in PMV between the PFS (1.424) and R/D groups (1.071) (P = 0.0024). When the cut-off value of the rate of change in the PMV was 1.20, patients whose rate of change in PMV was ≥ 1.20 had longer PFS (P = 0.0231) and overall survival (P = 0.0229) than those whose rate of change was < 1.20. CONCLUSION: Pediatric patients with malignant solid tumors and increased skeletal muscle mass during treatment have a good prognosis.

Frequent breakpoints of focal deletion and uniparental disomy in 22q11.1 or 11.2 segmental duplication region reveal distinct tumorigenesis in rhabdoid tumor of the kidney.

SMARCB1 is mutated in most rhabdoid tumors (RTs) developing in the kidney (RTK) and various other organs. Focal deletions found in patients with 22q11.2 deletion syndrome show breakpoints within clusters of segmental duplications (SDs), and those in some RTs show breakpoints in the 22q11-q12 region. SDs are known to cause focal deletion mediated by non-allelic homologous recombination. The present study identified SMARCB1 alterations in all 30 RTKs, using SNP array CGH, MLPA, and sequence analyses. Twenty-eight tumors had a total of 51 breakpoints forming focal 22q deletion and/or uniparental disomy (22qUPD), and the other two had compound mutation with no breakpoints in 22q. Twenty-four (47.1%) of the 51 breakpoints were within SDs, and occurred in 16 (53.3%) of the 30 tumors. The association of breakpoints with SDs was found not only in focal deletion, but also in 22qUPD, indicating that SDs mediate the first and second hits (focal deletion) and the second hit (22qUPD) of SMARCB1 alteration. Of the 51 breakpoints, 14 were recurrent, and 10 of the 14 were within SDs, suggesting the presence of hotspots in the 22q11.2 region. One recurrent breakpoint outside SDs resided in SMARCB1, suggesting inactivation of the gene by out-of-frame fusion. The association between SDs and focal deletion has been reported in two other types of cancer. RTKs may be the third example of SD-associated tumors. Thus, the present study indicated that RTKs exploit genomic instability in the 22q11.1-11.2 SDs region, and 22qUPD caused by mitotic recombination may also be mediated by SDs.

Current thoracoscopic approach for mediastinal neuroblastoma in Japan-results from nationwide multicenter survey.

BACKGROUND: Minimally invasive surgery (MIS) is appropriate for the treatment of some neuroblastomas (NBs); however, the indications and technical issues are unclear. This study aimed to clarify the current status of MIS for mediastinal NB in Japan. METHODS: Preliminary questionnaires requesting the numbers of neuroblastoma cases in which MIS was performed from 2004 to 2016 were sent to 159 Japanese institutes of pediatric surgery. Secondary questionnaires were sent to institutions with MIS cases to collect detailed data. RESULTS: One hundred thirty-four (84.2%) institutions returned the preliminary questionnaire and 83 institutions (52.2%) reported a total of 1496 operative cases. MIS was performed for 175 (11.6%) cases. Among the 175 cases, completed forms of 140 patients were returned and 40 (male, n = 28; female, n = 12) cases had mediastinal NB. Fourteen patients received thoracoscopic biopsy, none were converted to thoracotomy. Twenty-eight patients received MIS for radical resection, none were converted to thoracotomy. Perioperative complications (Horner's syndrome) were recognized after radical resection in one (2.5%) case. CONCLUSIONS: MIS was performed in a limited number of mediastinal NB cases. A thoracoscopic approach would be feasible for mediastinal NB.

Immunologic Effects of Sirolimus in Patients With Vascular Anomalies.

Emerging data have suggested that sirolimus may be a treatment option for complicated vascular anomalies (VAs). The present study aimed to investigate the immunologic effects of sirolimus treatment for 6 months in patients with VAs. Blood samples obtained from the patients enrolled in 2 multicenter studies to investigate the efficacy of sirolimus for VAs before and after sirolimus treatment for 6 months were used. Data for total white blood cell count, absolute lymphocyte count, serum immunoglobulins (Igs) levels (IgG, IgA, IgM), lymphocyte proliferation assays with mitogens including phytohemagglutinin and concanavalin A, and flow cytometric analysis of lymphocyte subsets were evaluated. A total of 18 patients with VAs receiving sirolimus treatment were included in the study. Comparisons of white blood cell, absolute lymphocyte count, IgG, IgA, IgM, and reaction rates of phytohemagglutinin and concanavalin A revealed no significant differences before and after treatment. No significant differences were observed in the absolute counts of lymphocyte subtypes before and after treatment, except for regulatory T-cell counts, which were significantly decreased after treatment. Severe infections were not observed during sirolimus treatment. The immunologic parameters assessed in the present study were hardly affected by sirolimus treatment for 6 months in patients with VAs.

The Influence of Sarcopenia on High-Risk Neuroblastoma.

PURPOSE: Sarcopenia is a syndrome that is defined by the loss of skeletal muscle mass, quality, and strength. In adult patients with malignancies, the presence of sarcopenia is known to be correlated with a poor prognosis; however, there have been no reports on the influence of sarcopenia on malignant tumors in pediatric patients. In the present study, we investigated whether or not sarcopenia affects the prognosis of high-risk neuroblastoma. MATERIALS AND METHODS: Thirteen patients with high-risk neuroblastoma who were treated according to the standard protocol at our hospital from 2007 to 2016 were divided into a progression-free survival group (n = 8) and a relapse/death group (n = 5). The rate of change in sarcopenia was calculated by comparing the psoas muscle area (PMA) of the L3-level lumbar spine on computed tomography before and after treatment with the standard protocol. The rate of change in the PMA, Kaup index, and serum albumin level were compared. Furthermore, we determined the cutoff rate of change in the PMA and compared the overall and progression-free survival. RESULTS: The rates of change in the PMA were 1.24 and 0.84 in the progression-free survival and relapse/death groups, respectively (P = 0.0472). There were no significant differences in the rates of change in the Kaup index or the serum albumin level of the two groups. The patients whose rate of change in the PMA was >1.00 showed a prolonged overall (P = 0.0078) and progression-free survival (P = 0.006). CONCLUSIONS: A decrease in the skeletal muscle mass was suggested to be a significant prognostic factor for high-risk neuroblastoma.

Japanese clinical practice guidelines for sacrococcygeal teratoma, 2017.

BACKGROUND: Sacrococcygeal teratoma (SCT) is the most common extragonadal germ cell tumor in neonates and infants. Although most cases of infantile SCT are benign tumors by nature, some develop into extremely large lesions, leading to massive bleeding, high-output heart failure, disseminated intravascular coagulation, and even fatal outcomes during the neonatal period. In addition, some patients may present with tumor recurrence, malignant transformation, long-term sequelae (including bladder and bowel dysfunction) and lower leg palsy during the long-term follow up. SCT, however, is very rare, and there are few opportunities to encounter this disease, therefore general physicians without expert credentials currently lack information relevant to clinical practice. For this reason, the research project committee has compiled guidelines concerning SCT. METHODS: The purpose of these guidelines was to share information concerning the treatment and follow up of infantile SCT. The guidelines were developed using the methodologies in the Medical Information Network Distribution System. A comprehensive search of the English- and Japanese-language articles in PubMed and Ichu-Shi Web identified only case reports or case series, and the recommendations were developed through a process of informal consensus. RESULTS: The clinical questions addressed the risk factors, the efficacy of cesarean section, the initial devascularization of tumor feeding vessels, interventional radiology, recommended clinical studies for follow up and possible long-term complications. CONCLUSIONS: These are the first guidelines for SCT to be established in Japan, and they may have huge clinical value and significance in terms of developing therapeutic strategies and follow up, potentially contributing to the improvement of the prognosis and quality of life of SCT patients.

Factors responsible for stage III disease in patients with Wilms tumor enrolled in the JWiTS-2 study.

BACKGROUND/OBJECTIVES: Treatment is more intensive for stage III Wilms tumor (WT) than for stages I and II non-metastatic WTs. Various factors including tumor spillage, unresectability, and lymph node metastasis are responsible for stage III disease. The present study aimed to not identify clinical factors associated with the features of stage III WT to establish new treatment strategies. DESIGN/METHODS: Of 166 patients with non-metastatic WT enrolled in the Japan Wilms Tumor Study (JWiTS)-2, 51 patients had stage III disease. The treatment protocol for JWiTS-2 was essentially the same as that in the National Wilms Tumor study (NWTS)-5. Local hospitals were surveyed to collect details of clinical findings related to stage III disease, and data regarding 45 (88%) patients were obtained. RESULTS: Nine patients with massive tumors underwent preoperative chemotherapy. Biopsy was performed in 6. Reduction in the tumor size was achieved in 8 of the 9 cases. Nephrectomy was finally performed in all of them. Thirty-six patients underwent primary nephrectomy. The reason for the stage III disease was lymph node metastasis (n = 9, 25%), tumor spillage (n = 20, 56%), and tumor extension/incomplete resection (n = 17, 47%). Some patients had more than one of these factors. Most patients were treated with the DD-4A regimen, and 43 (95.6%) of the 45 patients received abdominal radiation therapy. Tumors recurred in three patients (local, 1; metastasis, 2), and two patients died. Overall and relapse-free survival rates were 95.2% and 90.8%, respectively. CONCLUSION: The prognosis of stage III WT was good. In the next stage, the doses of chemotherapy and radiotherapy should be reduced to avoid late effects. The high rate of tumor spillage after primary resection suggests that preoperative chemotherapy should be started instead of aggressive tumor resection in the large tumor cases with surgical risks.

Navigation surgery using indocyanine green fluorescent imaging for hepatoblastoma patients.

BACKGROUND: Technology for detecting liver tumors and identifying the bile ducts using indocyanine green (ICG) has recently been developed. However, the usefulness and limitations of ICG navigation surgery for hepatoblastoma (HB) have not been fully clarified. We herein report our experiences with surgical navigation using ICG for in HB patients. METHODS: In 5 HB patients, 10 ICG navigation surgeries were performed using a 10-mm infrared fluorescence imaging scope after the injection of 0.5 mg/kg ICG intravenously. The surgical and clinical features were collected retrospectively. RESULTS: Navigation surgery using ICG was performed for primary liver tumors in 4 cases, and the timing of ICG injection was 90.5 ± 33.7 h before the operation. All tumors exhibited intense fluorescence from the liver surface. ICG navigation for the primary liver tumor was useful for detecting the residual tumor at the stump and invasion to the diaphragm during surgery. Six lung surgeries using ICG navigation were performed. The timing of ICG injection was 21.8 ± 3.4 h before the operation. The size of the metastatic tumor was 7.4 ± 4.1 mm (1.2-15 mm). Of 11 metastatic tumors detected by computed tomography (CT), 10-including the smallest tumor (1.2 mm)-were able to be detected by ICG from the lung surface. The depth of the 10 ICG-positive tumors from the lung surface was 0.9 ± 1.9 mm (0-6 mm), and the depth of the single ICG-negative tumor was 12 mm. One lesion not detected by CT showed ICG false positivity. CONCLUSION: Navigation surgery using ICG for patients with HB was useful for identifying tumors and confirming complete resection. However, in ICG navigation surgery, we must be aware of the limitations with regard to the tumor size and the depth from the surface.

Natural antibody against neuroblastoma of TH-MYCN transgenic mice does not correlate with spontaneous regression.

The mechanism underlying the spontaneous regression of neuroblastoma is unclear. Although it was hypothesized that this regression occurs via an immunological mechanism, there is no clinical evidence, and no animal models have been developed to investigate the involvement of immune systems, especially natural antibodies, against neuroblastoma. We performed an immunological analysis of homo- and heterozygous TH-MYCN transgenic mice as a model of aggressive neuroblastoma. Mice with no or small (<5 mm) tumors showed higher antibody titers in plasma than mice with large (>5 mm) tumors. A significant negative correlation was observed between the tumor diameter and the titer of antitumor antibody. This antibody had complement-dependent cytotoxicity but not antibody-dependent cellular cytotoxicity against neuroblastoma cells. Moreover, B-cell depletion had no effect on the tumor incidence in vivo. We revealed that TH-MYCN transgenic mice have a natural antibody against neuroblastoma that correlate with tumor size. However, this antibody does not correlate with the spontaneous regression of neuroblastoma. Thus, the function of the natural antibody is limited.

[Survey of Anticancer Drug Exposure to Attendant Families in Pediatric Medical Centers].

The occupational exposure to hazardous drugs(HD)has already been investigated; however, the actual exposure of the attendant family members of patients with childhood cancer has remained unknown. Here, we analyzed cyclophosphamide (CPM)exposure in attendant family members and the environment after the administration of CPM to patients with pediatric cancer. CPM of 320(8.39-1,510)ng from infant-families and 0(0-58.4)ng from adolescent-families were detected(p= 0.01). The exposure of infant-families was significantly greater than those of adolescent-families. In addition, CPM were detected in the hot water after bathing the infant, underwear, and sheets. We elucidated that the exposures take place through body fluid and excretions of the children. In the field of childhood cancer, HD exposure measures should be taken according to the age of the child to minimize health damage to medical personnel, family members, and other children who share the room. Nurses are recommended to educate the patients and their family members about preventing exposure to HD in pediatric medical centers.

A new innovative laparoscopic fundoplication training simulator with a surgical skill validation system.

PURPOSE: We developed and validated a specific laparoscopic fundoplication simulator for use with the objective endoscopic surgical skills evaluation system. The aim of this study was to verify the quality of skills of surgeons. MATERIALS AND METHODS: We developed a 1-year-old infant body model based on computed tomography data and reproduced pneumoperitoneum model based on the clinical situation. The examinees were divided into three groups: fifteen pediatric surgery experts (PSE), twenty-four pediatric surgery trainees (PSN), and ten general surgeons (GS). They each had to perform three sutures ligatures for construction of Nissen wrap. Evaluate points are time for task, the symmetry of the placement of the sutures, and the uniformity of the interval of suture ligatures in making wrap. And the total path length and velocity of forceps were measured to assess bi-hand coordination. RESULTS: PSE were significantly superior to PSN regarding total time spent (p < 0.01) and total path length (p < 0.01). GS used both forceps faster than the other groups, and PSN used the right forceps faster than the left forceps (p < 0.05). PSE were shorter with regard to the total path length than GS (p < 0.01). PSE showed most excellent results in the symmetry of the wrap among three groups. CONCLUSION: Our new model was used useful to validate the characteristics between GS and pediatric surgeon. Both PSE and GS have excellent bi-hand coordination and can manipulate both forceps equally and had superior skills compared to PSN. In addition, PSE performed most compact and accurate skills in the conflicted operative space.

Preoperative simulation regarding the appropriate port location for laparoscopic hepaticojejunostomy: a randomized study using a disease-specific training simulator.

PURPOSE: We verified the appropriate port location for laparoscopic hepaticojejunostomy using a comprehensive laparoscopic training simulator. METHODS: We developed a hepaticojejunostomy model, consist of common hepatic duct and intestine and participants required to place two sutures precisely using two different port locations (A: standard port location, B: modified port location). The order of tasks was randomly determined using the permuted block method (Group I: Task A â†’ Task B, Group II: Task B â†’ Task A). The time for task completion and total number of errors were recorded. In addition, we evaluated the spatial paths and velocity of both forceps. Statistical analyses were performed using a statistical software program. RESULTS: The time for the task, the total error score, and the spatial paths and velocity of both forceps were not significantly different between groups I and II. Furthermore, the port location and order of tasks (group I or group II) did not significantly affect the results. In contrast, there were significant differences in the performance between experts and novices, who were classified as such based on the total number of experienced endoscopic surgeries. CONCLUSION: Preoperative port simulation in advanced surgery using our artificial simulator is feasible and may facilitate minimally invasive surgery for children.

Objective assessment of the suture ligature method for the laparoscopic intestinal anastomosis model using a new computerized system.

BACKGROUND: The purpose of this study was to develop a new objective assessment system for the suture ligature method employed in the laparoscopic intestinal anastomosis model. Suturing skills were evaluated objectively using this system. METHODS: This study compared 17 expert surgeons, each of whom had performed >500 laparoscopic procedures, with 36 novice surgeons, each of whom had performed <15 laparoscopic procedures. Each examinee performed a specific skill assessment task using an artificial model that mimics living tissue, which is linked with the Suture Simulator Instruction Evaluation Unit. The model used internal air pressure measurements and image processing to evaluate suturing skills. Five criteria were used to evaluate the skills of participants. RESULTS: The volumes of air pressure leak in the expert and novice groups were 21.13 ± 6.68 and 8.51 ± 8.60 kPa, respectively. The numbers of full-thickness sutures in the expert and novice groups were 2.94 ± 0.24 pairs and 2.47 ± 0.77 pairs, respectively. Suture tensions in the expert and novice groups were 60.99 ± 11.81 and 80.90 ± 16.63 %, respectively. The areas of wound-opening in the expert and novice groups were 1.76 ± 2.17 and 11.06 ± 15.37 mm(2), respectively. The performance times in the expert and novice groups were 349 ± 120 and 750 ± 269 s, respectively. Significant differences between the expert and novice groups for each criterion were observed. The acceptable range of values for each criterion except for the number of full-thickness sutures was statistically defined by the performance of the expert group. CONCLUSIONS: Our system is useful for the quantitative assessment of suturing skill in laparoscopic surgery. We believe that this system is a useful tool for training and assessment of laparoscopic surgeons.

The effect of forceps manipulation for expert pediatric surgeons using an endoscopic pseudo-viewpoint alternating system: the phenomenon of economical slow and fast performance in endoscopic surgery.

PURPOSE: Endoscopic surgery is performed under a horizontal view in comparison to the vertical view that is associated with open surgery. We developed an endoscopic pseudo-viewpoint alternation system with out any scope action. We investigate the effect of this novel system on forceps manipulation among expert pediatric surgeons. METHODS: Six expert pediatric surgeons performed a Nissen wrap in a fundoplication simulator either with or without this system. The constructed Nissen wrap was evaluated. The total path length and the average velocity of the forceps were also analyzed. RESULTS: The times required either with or without this system were 587.5 ± 122.7 and 634.0 ± 212.4 s (p = 0.45), respectively. The total path lengths of right and left forceps either with or without this system were 12,309 ± 2495.5 and 15,726 ± 5649.6 mm (p = 0.07), 10,091 ± 2439.2 and 12,575 ± 5511.1 mm (p = 0.11), respectively. The average velocity of the right and left forceps with or without this system were 26.9 ± 5.29 and 31.6 ± 1.62 mm/s (p = 0.04), 21.6 ± 2.48 and 25.5 ± 6.48 mm/s (p = 0.15), respectively. There was no significance in the suture balance and suture interval. CONCLUSION: The endoscopic pseudo-viewpoint alternation system thus made it possible for expert pediatric surgeons to carry out slow and economical forceps manipulation. These effects make it possible for surgeons to perform safe and precise surgery, thus leading to a shortening of operation time.

Effectiveness of short-term endoscopic surgical skill training for young pediatric surgeons: a validation study using the laparoscopic fundoplication simulator.

PURPOSE: Pediatric surgeons require highly advanced skills when performing endoscopic surgery; however, their experience is often limited in comparison to general surgeons. The aim of this study was to evaluate the effectiveness of endoscopic surgery training for less-experienced pediatric surgeons and then compare their skills before and after training. METHODS: Young pediatric surgeons (n = 7) who participated in this study underwent a 2-day endoscopic skill training program, consisting of lectures, box training and live tissue training. The trainees performed the Nissen construction tasks before and after training using our objective evaluation system. A statistical analysis was conducted using the two-tailed paired Student's t tests. RESULTS: The time for task was 984 ± 220 s before training and 645 ± 92.8 s after training (p < 0.05). The total path length of both forceps was 37855 ± 10586 mm before training and 22582 ± 3045 mm after training (p < 0.05). The average velocity of both forceps was 26.1 ± 3.68 mm/s before training and 22.9 ± 2.47 mm/sec after training (p < 0.1). The right and left balance of suturing was improved after training (p < 0.05). CONCLUSION: Pediatric surgery trainees improved their surgical skills after receiving short-term training. We demonstrated the effectiveness of our training program, which utilized a new laparoscopic fundoplication simulator.

Three-dimensional liver model based on preoperative CT images as a tool to assist in surgical planning for hepatoblastoma in a child.

The patient is a 3-year-old female diagnosed with PRETEXT IV hepatoblastoma (HB). Although the tumor was decreased after the neoadjuvant chemotherapy, HB still located at the porta hepatis. The patient underwent extended left lobectomy successfully after surgical simulation using three-dimensional (3D) printing liver model based on preoperative CT.

Analysis of hand motion differentiates expert and novice surgeons.

BACKGROUND: The number of operations performed by a surgeon may be an indicator of surgical skill. The hand motions made by a surgeon also reflect skill and level of expertise. We hypothesized that the hand motions of expert and novice surgeons differ significantly, regardless of whether they are familiar with specific tasks during an operation. METHODS: This study compared 11 expert surgeons, each of whom had performed >100 laparoscopic procedures, and 27 young surgeons, each of whom had performed <15 laparoscopic procedures. Each examinee performed a specific skill assessment task, in which instrument motion was monitored using magnetic tracking system. We analyzed the paths of the centers of gravity of the tips of the needle holders and the relative paths of the tips using two mathematical methods of detrended fluctuation analysis and unstable periodic orbit analysis. RESULTS: Detrended fluctuation analysis showed that the exponent in the function describing the initial scaling exponent (α1) differed significantly for experts and novices, being close to 1.0 and 1.5, respectively (P < 0.01). This indicated that the expert group had a greater long-range coherence with an intrinsic sequence and smooth continuity among a series of motions. Likewise, unstable periodic orbit analysis showed that the second period of unstable orbit was significantly longer for experts in comparison with novices (P < 0.01). This demonstrates mathematically that the hands of experts are more stable when performing laparoscopic procedures. CONCLUSIONS: Objective evaluation of hand motion during a simulated laparoscopic procedure showed a significant difference between experts and novices.