Surgical simulation of pediatric laparoscopic dismembered pyeloplasty: Reproducible high-fidelity animal-tissue model.

PURPOSE: To provide a high-fidelity, animal tissue-based model for the advanced surgical simulation of laparoscopic dismembered pyeloplasty in infants and children. MATERIALS AND METHODS: A previously described animal tissue model using chicken crop was surgically modified and attached to piglet kidney specimens in order to provide organ model realistically resembling infant and children hydronephrosis for simulation of dismembered laparoscopic pyeloplasty. Dismembered pyeloplasty could then be carried out in a standard pelvi-trainer using a standard instrumentation as in a regular case. RESULTS: The model created could prove to be a high-fidelity, animal tissue model for the surgical simulation of dismembered pyeloplasty. The surgical modification of the used animal tissues of chicken crop and piglet kidney respectively used in this fusion model was able to provide a high grade of resembling a realistic organ situs for infant and pediatric pyeloplasty, respectively. The surgical procedure could be carried out as a simulation of a regular case while providing high-grade realistic anatomy, adequate sizes of a dilated renal pelvis and of the ureter, respectively. Biological as well as haptic conditions of the tissue were able to resemble human tissue in a high grade as well. DISCUSSION: Despite a live animal model has been described for dismembered pyeloplasty, its time-consuming creation and possible conflict concerning animal welfare cadaver models are more practicable for daily simulation. In literature so far animal-tissue models described range from folded chicken skin to a chicken crop model. While these types of models have its own advantages and disadvantages none of them provide adequate anatomical relations. By dissecting chicken crop and fixating it to a piglet's kidney this limitation could be overcome and furthermore will enable future modifications for a perfused model for laparoscopic dismembered pyeloplasty. CONCLUSION: The fusion of a previously described tissue model of chicken crop for simulation of pyeloplasty along with also previously used piglet kidneys for surgical simulation can provide a highly realistic model for surgical simulation of pediatric dismembered laparoscopic pyeloplasty. In addition, this model rules out the disadvantage of native animal kidney specimens which the lack of pathology of a dilated renal pelvis. Surgical modification is an established method to provide high-fidelity animal tissue models for surgical simulation and therefore training of complex procedures, respectively. For simulation purposes in pediatric laparoscopic urology, i.e., reconstructive procedures such as dismembered pyeloplasty this model appears to be promising in terms of providing realistic pathology in pediatric dimensions.

On-site CAD templates reduce surgery time for complex craniostenosis repair in infants: a new method.

INTRODUCTION: The surgical correction of craniostenosis in children is a time-consuming and taxing procedure. To facilitate this procedure, especially in infants with complex craniostenosis, we refined the computer-aided design and manufacturing technique (CAD/CAM) based on computed tomography (CT)-generated DICOM data. We used cutting guides and molding templates, which allowed the surgeon to reshape and fixate the supraorbital bar extracorporeally on a side table and to control the intracorporal fit without removing the template. METHOD AND PATIENTS: To compare our traditional concept with the possibility of preoperative virtual planning (PVP) technique, the surgical treatment and courses of 16 infants with complex craniostenosis following fronto-orbital advancement (FOA) (age range 8-15 months) were analyzed in two groups (group 1: traditional, control group n = 8, group 2: CAD/CAM planned, n = 8). RESULTS: While in both groups, the head accurately reshaped postoperatively during the follow-up; the CAD group 2 showed a significantly shorter operating time with a mean of 4 h 25 min compared with group 1 with a mean of 5 h 37 min (p = 0.038). Additionally, the CAD group 2 had a significantly lower volume of blood loss (380 ml vs. 575 ml mean, p = 0.047), lower blood transfusion volume (285 ml vs. 400 ml mean, p = 0.108), lower fresh frozen plasma (FFP) volume (140 ml vs. 275 ml mean, p = 0.019), shorter stay in the pediatric intensive care unit (PICU) (3 vs. 5 days mean (p = 0.002), and shorter total length of hospital stay (6 days vs. 8 days mean, p = 0.002). CONCLUSION: CAD/CAM cutting guides and templates offer optimizing operative efficiency, precision, and accuracy in craniostenosis surgery in infants. As shown in this single-center observational study, the use of on-site templates significantly accelerates the reconstruction of the bandeau. The virtual 3D planning technique increases surgical precision without discernible detrimental effects.

Osteoclastic craniectomy for scaphocephaly in infants results in physiological head shapes.

INTRODUCTION: Sagittal synostosis leading to scaphocephaly is the most common type of craniostenosis being operated. Different treatment options are known, but the optimal treatment method is still controversial. Head growth indicated by measurements of the head´s circumference and cephalic index (CI) are valid surrogate parameters for normal head shapes in children. The aim of the study was to analyze if osteoclastic craniectomy (OC) in scaphocephaly children at four to ten months of age results in normal head shapes. PATIENTS AND METHODS: Twenty-seven patients with scaphocephaly underwent OC between 2003 and 2011. The mean patient age at the time of surgery was 6.75 months. The body weight was between 6.1 and 9.3 kg, mean 8.0 kg. The average duration of surgery was 108 minutes. The mean blood loss during the procedure was 168 ml and the mean amount of erythrocyte transfusion was 152 ml. The mean time spent on the ICU was 1.48 days and the mean of total hospital stay was 5.81 days. The operative method is described. During the mean follow-up time of 6.3 years (min 3.8, max 10.4, median 7.1) focus was set on the patient´s head growth and cephalic index (CI) following OC. For statistical reason the follow up period was divided into three groups: follow up 2-4 years, 5-7 years and 8-10 years. RESULTS: For all cases the total head growth was 9.5cm (mean) during the follow up period of 6.3 years. Analyzing the mean head growth by bootstrapping analysis, the three observational groups showed a significant increase of the head circumference in all cases being analyzed: group 1 p=0.003, group 2 p=0.005 and group 3 p=0.028 Evaluation of the CI showed a statistically significant change from a pathologic value of 0.67 (mean) preoperatively to a normal value of 0.78 (mean) postoperatively during the follow up analyzing all patients. To precise these findings, the bootstrapping analysis showed in the first period an increase of the mean CI not reaching statistical significance (p=0.351). Analyzing the second and third period the CI significantly increased in both groups (p=0.016 and p=0.037). All patients showed a nearly complete re-ossification during the follow up period. No secondary operation was necessary in any patient of this cohort. CONCLUSION: As shown in this single-center observational study, the surgical intervention significantly improved the cephalic index and resulted in a symmetric head shape with excellent aesthetic appearance. The results were not dependent on postoperative helmet therapy, and compliance of caregivers. Re-ossification reached 100% within the observation period. According to these data, we recommend osteoclastic craniectomy as the method of choice in infants six to twelve months of age.

Adolescent varicocele: Efficacy of indication-to-treat protocol and proposal of a grading system for postoperative hydroceles.

BACKGROUND: Varicocele is a common urologic anomaly in adolescent males; however, evidence-based treatment guidelines do not exist. Hydroceles are known to be a common complication after surgical therapy, with a wide variation in the reported incidence between 1 and 40%. AIM: This study aimed to introduce a standardized indication-to-treat protocol and prove its efficacy by analyzing the outcome of patients. Secondly, it aimed to better define postoperative hydroceles because the wide variation of reported incidence is attributed to a lack of definition. METHODS: Our standardized treatment protocol included an initial assessment with clinical grading of varicoceles, ultrasound evaluation of testicular volume, and calculation of the atrophy index. Indications for surgical treatment were testicular volume asymmetry >20%, discomfort and pain, or bilateral varicocele. The Palomo procedure (laparoscopically since 2005) was the standard procedure. Postoperative hydroceles were graded according to clinical findings and symptoms: Grade I, sonographic chance finding without clinical correlate; Grade II, palpable but clinically insignificant; Grade III, symptomatic. All patients treated according to the defined protocol were prospectively monitored between January 2001 and December 2015. RESULTS: A total of 129 patients with left varicocele were referred to our institution; 70 fulfilled the indication criteria for surgical treatment. Twenty-eight of these patients were treated for volume asymmetry, 26 of these showed catch-up growth. Forty-two patients were treated for discomfort and pain; the symptoms subsided in all of them. Postoperative hydroceles were detected in 36 patients (51%). In 29 patients this was a sonographic chance finding (Grade I). Three patients showed a palpable but clinically insignificant postoperative hydrocele (Grade II) and four patients (5.7%) showed symptomatic hydrocele (Grade III) where treatment was recommended. DISCUSSION: The treatment protocol allowed judicious indication for surgery and postoperative outcomes similar to previous reports. The high rate of catch-up growth in operated cases represents a proxy for successful treatment in cases where more precise parameters, like semen quality or paternity rate, were not yet detectable. The introduced grading system for postoperative hydroceles provs to be a valid and appropriate instrument, and promises to be a standardized method for comparing outcomes in future studies. CONCLUSION: The indication-to-treat protocol proved to be easily applicable, highly efficient, and have outcomes comparable to international literature. The necessity for a standardized grading of postoperative hydroceles was underscored in the data.

"Resident as teacher" in pediatric surgery: Innovation is overdue in Central Europe.

PURPOSE: We set out to evaluate how residents in pediatric surgery learn and how they teach. We hypnotized that European residents learn as much from their peers and teach as much as their fellows worldwide, but that they receive comparably less educational training. METHODS: An online questionnaire was distributed to the participants of the combined annual meeting for German, Swiss and Austrian residents in pediatric surgery. Participants were asked whom they learn from in different workplace environments (ward, operating room, emergency department), how, when and why they adopt the role of teacher and how they were prepared for this role. RESULTS: Response rate was 48%. 65 questionnaires were analyzed. Residents stated that they predominantly learn from each other on wards and in the emergency department, less frequently in the operating room. They ranked fellow residents as first or second most important source of instruction. 53% of participants have never had any educational training, for another 33% the instruction was being done by fellow residents without any set curriculum. 93% of the participating residents had no or did not know about any resident as teacher training program available to them. Nevertheless, motivation to teach was stated to be high and interest in educational training was assured. CONCLUSIONS: Our data delivers evidence that peer teaching during residency is the rule rather than the exception in Central Europe. Educational training however is scarce. Resident as teacher-training programs need to be introduced. Next to local initiatives, we strongly recommend national initiatives powered by regulatory authorities and surgical associations. TYPE OF STUDY: Research paper. LEVEL OF EVIDENCE: II.

[Is it Possible to Arouse Interest in a Career in Traumatology with a Curricular Course in Medical School?] / Kann mit praxisorientierter curricularer Lehre das Interesse am Fach Orthopädie und Unfallchirurgie geweckt werden?

Background: There is a serious lack of young doctors in trauma surgery, which has intensified in recent years. The reasons are complex. Studies have shown that the interest in starting a career in surgery significantly decreases during medical school. To counteract the lack of young talent in the clinic, interest in the subject should be aroused in medical school. The aim of the present study was to evaluate current teaching at our university, where trauma surgery is a curricular subject with mandatory attendance for all medical students. Material and Methods: The current curriculum is intended for medicine students in their fifth year. The curriculum comprises lectures, practical courses and observation modules held in small groups. Students are provided with an experienced surgeon as teacher and mentor for the whole week. A teaching and training centre is available for the practical courses. In an anonymised questionnaire, students were asked about their overall assessment and the training success of practical and theory-oriented modules, as well as their specific interest in traumatology. Results: The evaluated curriculum gave very good results, with an overall rating of 1.53 (average) on a 6-point Likert scale in the overall assessment. It could be shown that students previously not interested in starting a career in trauma surgery showed significantly more interest in the subject after the curriculum. The practical parts scored best in the individual assessment. Conclusion: We showed that intensive teaching can arouse interest in traumatology in students who had been indifferent to orthopaedics and traumatology.

Undescended testis? How best to teach the physical examination.

BACKGROUND: Undescended testis in boys is common. Guidelines recommend surgical treatment between the ages of 6 months and 2 years; nevertheless, orchidopexy is frequently performed at later ages. One reason is the belated diagnosis due to a perceived difficulty in the physical examination (PE) and correct localization of the testis. OBJECTIVES: We aimed to find an effective method for teaching the physical examination of the testis in a child. STUDY DESIGN: An interdisciplinary team developed teaching sessions, including an educational video and a simulator. Medical students (n = 133) were randomized into three groups: self-study only, video, and video and simulator. The sessions were carried out and quantitative feedback was collected from the teachers and students. The learning achievements of the different groups were assessed with an objective structured clinical examination (OSCE). The differences in mean OSCE results between all three groups were tested using one-way analysis of variance (ANOVA). For multiple pairwise comparisons, a closed testing procedure was performed using unpaired t-tests. RESULTS: The self-study only group acquired the poorest results in the OSCE, with a mean score of 5.1 out of 10. The video-only-group reached a mean of 6.7, and the video-and-simulator group performed best with a mean score of 8.5. The differences between all three groups were found to be statistically significant, with P = 0.007. The attached figure illustrates this data. If analyzed in pairs, this difference was particularly apparent between the groups self-study only vs video and simulator, with P = 0.002. Qualitative feedback revealed doubtful effectiveness for educational videos, but positive reactions to training on a simulator. DISCUSSION: The poor results of the self-study-only group were in accordance with the literature, where textbook learning was found not to increase OSCE results. The effectiveness of video tutorials remains doubtful; studies focusing on this teaching method are divergent and the present students' feedback supports this data. The effective teaching with the simulator has been proven for other skills (i.e. ultrasound skills). The analyzed cohort for this study was small, and the study should be repeated at different institutions and with larger numbers of students to assure generalizability. CONCLUSIONS: Low-fidelity pediatric simulators with palpable testis are available and are able to improve examining skills in medical students. We hope the presented study inspires medical educators in their teaching of the PE of the pediatric testis.

Differences between intrinsic and extrinsic ureteropelvic junction obstruction related to crossing vessels: histology and functional analyses.

PURPOSE: In children, ureteropelvic junction obstruction (UPJO) is mostly caused by intrinsic factors (IUPJO); extrinsic UPJO are rare and often due to crossing vessels (CVs). METHODS: We retrospectively reviewed all data of children with UPJO that underwent surgery in our institution from 2004 to 2011. Analyses included age at surgery, gender, preoperative and postoperative results of ultrasound and renal scans [differential renal function (DRF); signs of obstruction], and pathology reports. Available histological specimens of cases with CV were compared to a random selection of intrinsic cases in a blinded fashion. After additional Masson's trichrome staining, the specimens were scored for fibrosis, muscular hypertrophy, and chronic inflammation. RESULTS: Out of 139 patients with UPJO, 39 cases were associated with CV. Median age at surgery was 68 months (range 2-194) in the CV group and 11.5 months (range 0-188) in IUPJO group. Laparoscopic dismembered pyeloplasty (LDMP) was carried out in 134 and open DMP in five patients. Preoperative ultrasound identified 28/39 cases with CV. DRF below 40 % was more frequently seen in CV patients (p = 0.020). Histological analyses revealed no differences between the CV and IUPJO specimens in total. CV patients with higher grades of muscular hypertrophy had lower preoperative DRF, compared to those with higher preoperative DRF (p = 0.026). Functional recovery after (L)DMP was excellent in both groups. CONCLUSION: We could not find any significant histological differences between CV and IUPJO in children. To obtain excellent functional recovery, surgical procedures with a definite correction of the UPJ should be preferred in paediatric patients with CV.

[Strategies for paediatric spleen and liver injuries]. / Behandlungsstrategien bei Verletzungen von Milz und Leber im Kindesalter.

Traumatic injuries of the spleen and liver are typically caused by age-related falls or sports and traffic accidents. Today, the non-operative management for isolated injuries is established and evidence-based guidelines are available. The intact abdominal wall and the limited space within the peritoneum produce a compression which is the pathophysiological explanation for the limitation of the haemorrhage. Precondition for the non-operative therapy is the radiology-based classification of the injury (organ injury scale) and a haemodynamically stable patient. Haemodynamic stability is, if necessary maintained with blood transfusion, volume substitutes and the administration of catecholamines. In cases of hilar vascular injury and devascularisation or haemodynamic instability of the patient, despite utilisation of the measures mentioned above, urgent operative therapy needs to be performed. Organ sparing surgery is the therapy of choice for both liver and spleen. The spleen is required for the development of a competent immune system in the growing organism. Liver injuries can be further complicated by injury to the bile system, which might require operative reconstruction. If a patient suffers from multiple injuries and spleen or liver are involved, the decision on the management needs to be taken individually, no guidelines exist but the rate for operative therapy increases. Independent of the dimensions of injury, an experienced paediatric surgeon with his multidisciplinary team, considering the anatomic and age specific characteristics of a child, achieves the best therapeutic results.

Neutrophilic myeloid-derived suppressor cells in cord blood modulate innate and adaptive immune responses.

Neonates show an impaired anti-microbial host defence, but the underlying immune mechanisms are not understood fully. Myeloid-derived suppressor cells (MDSCs) represent an innate immune cell subset characterized by their capacity to suppress T cell immunity. In this study we demonstrate that a distinct MDSC subset with a neutrophilic/granulocytic phenotype (Gr-MDSCs) is highly increased in cord blood compared to peripheral blood of children and adults. Functionally, cord blood isolated Gr-MDSCs suppressed T cell proliferation efficiently as well as T helper type 1 (Th1), Th2 and Th17 cytokine secretion. Beyond T cells, cord blood Gr-MDSCs controlled natural killer (NK) cell cytotoxicity in a cell contact-dependent manner. These studies establish neutrophilic Gr-MDSCs as a novel immunosuppressive cell subset that controls innate (NK) and adaptive (T cell) immune responses in neonates. Increased MDSC activity in cord blood might serve as key fetomaternal immunosuppressive mechanism impairing neonatal host defence. Gr-MDSCs in cord blood might therefore represent a therapeutic target in neonatal infections.