Consensus Paper: Neurophysiological Assessments of Ataxias in Daily Practice.

The purpose of this consensus paper is to review electrophysiological abnormalities and to provide a guideline of neurophysiological assessments in cerebellar ataxias. All authors agree that standard electrophysiological methods should be systematically applied in all cases of ataxia to reveal accompanying peripheral neuropathy, the involvement of the dorsal columns, pyramidal tracts and the brainstem. Electroencephalography should also be considered, although findings are frequently non-specific. Electrophysiology helps define the neuronal systems affected by the disease in an individual patient and to understand the phenotypes of the different types of ataxia on a more general level. As yet, there is no established electrophysiological measure which is sensitive and specific of cerebellar dysfunction in ataxias. The authors agree that cerebellar brain inhibition (CBI), which is based on a paired-pulse transcranial magnetic stimulation (TMS) paradigm assessing cerebellar-cortical connectivity, is likely a useful measure of cerebellar function. Although its role in the investigation and diagnoses of different types of ataxias is unclear, it will be of interest to study its utility in this type of conditions. The authors agree that detailed clinical examination reveals core features of ataxia (i.e., dysarthria, truncal, gait and limb ataxia, oculomotor dysfunction) and is sufficient for formulating a differential diagnosis. Clinical assessment of oculomotor function, especially saccades and the vestibulo-ocular reflex (VOR) which are most easily examined both at the bedside and with quantitative testing techniques, is of particular help for differential diagnosis in many cases. Pure clinical measures, however, are not sensitive enough to reveal minute fluctuations or early treatment response as most relevant for pre-clinical stages of disease which might be amenable to study in future intervention trials. The authors agree that quantitative measures of ataxia are desirable as biomarkers. Methods are discussed that allow quantification of ataxia in laboratory as well as in clinical and real-life settings, for instance at the patients' home. Future studies are needed to demonstrate their usefulness as biomarkers in pharmaceutical or rehabilitation trials.

Effects and efficacy of laparoscopic fundoplication in children with GERD: a prospective, multicenter study.

INTRODUCTION: Laparoscopic antireflux surgery (LARS) in children primarily aims to decrease reflux events and reduce reflux symptoms in children with therapy-resistant gastroesophageal reflux disease (GERD). The aim was to objectively assess the effect and efficacy of LARS in pediatric GERD patients and to identify parameters associated with failure of LARS. METHODS: Twenty-five children with GERD [12 males, median age 6 (2-18) years] were included prospectively. Reflux-specific questionnaires, stationary manometry, 24-h multichannel intraluminal impedance pH monitoring (MII-pH monitoring) and a 13C-labeled Na-octanoate breath test were used for clinical assessment before and 3 months after LARS. RESULTS: After LARS, three of 25 patients had persisting/recurrent reflux symptoms (one also had persistent pathological acid exposure on MII-pH monitoring). New-onset dysphagia was present in three patients after LARS. Total acid exposure time (AET) (8.5-0.8 %; p < 0.0001) and total number of reflux episodes (p < 0.001) significantly decreased and lower esophageal sphincter (LES) resting pressure significantly increased (10-24 mmHg, p < 0.0001) after LARS. LES relaxation, peristaltic contractions and gastric emptying time did not change. The total number of reflux episodes on MII-pH monitoring before LARS was a significant predictor for the effect of the procedure on reflux reduction (p < 0.0001). CONCLUSIONS: In children with therapy-resistant GERD, LARS significantly reduces reflux symptoms, total acid exposure time (AET) and number of acidic as well as weakly acidic reflux episodes. LES resting pressure increases after LARS, but esophageal function and gastric emptying are not affected. LARS showed better reflux reduction in children with a higher number of reflux episodes on preoperative MII-pH monitoring.

Perioperative hospital mortality at a tertiary paediatric institution.

BACKGROUND: Research in postoperative mortality is scarce. Insight into mortality and cause of death might improve and innovate perioperative care. The objective for this study was to report the 24-hour and 30-day overall, and surgery and anaesthesia-related, in-hospital mortality at a tertiary paediatric hospital. METHODS: All patients <18 yr old who underwent anaesthesia with or without surgery between January 1, 2006, and December 31, 2012, at the Wilhelmina Children's Hospital, Utrecht, The Netherlands, were included in this retrospective cohort study. Causes of death within 30 days were identified and tabulated into four major categories according to principal cause. RESULTS: A total of 45,182 anaesthetics were administered during this 7-yr period. The all-cause 24-hour hospital mortality was 13.1 per 10,000 anaesthetics (95% CI: 9.9-16.8) and the all-cause 30-day in-hospital mortality was 41.6 per 10,000 anaesthetics (95% CI: 35.9-48.0). In total five patients were partially contributable to anaesthesia (30-day mortality: 1.1/10,000, 95% CI: 0.4-2.6) and four patients were partially contributable to surgery (30-day mortality: 0.9/10,000, 95% CI: 0.2-2.3). Mortality was higher in neonates and infants, children with ASA physical status III and IV, and emergency- and cardiothoracic surgery. CONCLUSIONS: Neonates and infants, children with ASA physical status III or poorer, and emergency- and cardiothoracic surgery are associated with a higher postoperative mortality. Anaesthesia- or surgery-related complications contribute to mortality in only a small amount of the deaths, indicating the relative safety of paediatric surgical and anaesthetic procedures.

Continuous theta-burst stimulation of the right superior temporal gyrus impairs self-motion perception.

Sensory input from the semicircular canals (SCC) and otolith organs is centrally combined with signals from other sensory modalities to continuously update the internal estimate of self-motion. Constant velocity vertical on-axis rotation leads to decay of the nystagmus response from the horizontal SCC and of perceived angular velocity (PAV), and when the rotation stops, a similar oppositely directed post-rotatory response occurs. Case reports and electrical stimulation studies suggest an involvement of the temporo-peri-Sylvian vestibular cortex in generating the PAV. Here, we transiently inhibited the right superior temporal gyrus (STG) by use of continuous theta-burst stimulation (cTBS) and predicted an accelerated decay of PAV compared to controls (n = 5 control session first, n = 1 cTBS session first). Constant velocity (100°/s) vertical on-axis rotations were applied over 75 s before (1 block) and after (3 blocks) cTBS over the right STG in six subjects. Breaks between the rotations (75 s) were initiated by abrupt stops. By use of a rotating potentiometer, subjects indicated the PAV during and after the chair rotations. Simultaneously eye positions were recorded using a scleral search coil. One subject was excluded for per-rotary analysis. Early after cTBS, the post-rotary PAV decay time constant (DTC) was significantly (9.4 ± 5.7 vs. 13.6 ± 5.9 s; p = 0.049) reduced (no directionality to this effect observed). Overall, post-rotary PAV showed a trend toward shortened DTC compared to the control trials (p = 0.086) in the first 25 min after cTBS, while per-rotary PAV was not significantly changed. Per-rotary and post-rotary aVOR DTC were not significantly changed after cTBS (p > 0.05). These findings support the hypothesis that the right STG is involved in mediating self-motion perception and can be modulated by cTBS.

Multiplanar reconstruction computed tomography for diagnosis of scaphoid waist fracture union: a prospective cohort analysis of accuracy and precision.

OBJECTIVE: To examine reliability and validity concerning union of scaphoid fractures determined by multiplanar reconstruction computed tomography randomized at 6, 12, and 24 weeks after injury. MATERIALS AND METHODS: We used Fleiss' kappa to measure the opinions of three observers reviewing 44 sets of computed tomographic scans of 44 conservatively treated scaphoid waist fractures. We calculated kappa for the extent of consolidation (0-24 %, 25-49 %, 50-74 %, or 75-100 %) on the transverse, sagittal and coronal views. We also calculated kappa for no union, partial union, and union, and grouped the results for 6, 12, and 24 weeks after injury. As the reference standard for union, CT scans were performed at a minimum of 6 months after injury to determine validity. RESULTS: Overall inter-observer agreement was found to be moderate (κ = 0.576). No union (κ = 0.791), partial union (κ = 0.502), and union (κ = 0.683) showed substantial, moderate, and substantial agreement, respectively. The average sensitivity of multiplanar reconstruction CT for diagnosing union of scaphoid waist fractures was 73 %. The average specificity was 80 %. CONCLUSIONS: Our results suggest that multiplanar reconstruction computed tomography is a reliable and accurate method for diagnosing union or nonunion of scaphoid fractures. However, inter-observer agreement was lower with respect to partial union.

How stable is perceived direction of gravity over extended periods in darkness?

Previous studies reported linear drift of perceived vertical for brief (≤10 min) observation periods. Here, we repeated estimates of direction of gravity up to 60 min to evaluate whether the drift is sustained, shows saturation or even reverses over time. Fifteen healthy human subjects repetitively adjusted a luminous line along subjective visual vertical (SVV) and horizontal (SVH) over periods of 5 min (constituting one block). We obtained seven blocks within 60 min in each subject for SVV and SVH. In between the first six blocks, subjects remained in darkness for 5 min each, whereas the lights were briefly turned on before block 7. We noted significantly (p < 0.05) increased errors in perceived direction of gravity by block 2 (SVV) and 3 (SVH). These increases disappeared after turning on the lights before block 7. Focusing on blocks 2-6, significant drift started from similar offset positions and pointed to the same direction in a majority of runs in 9/15 (SVV) and 11/15 (SVH) subjects. When pooling data from all blocks, orthogonality of errors was lost in all subjects. Trial-to-trial variability remained stable over the seven runs for SVV and SVH. Only when pooling all runs, precision was significantly (p < 0.05) higher for the SVH. Our findings suggest that perceived direction of gravity continues to fluctuate over extended recording periods with individuals showing unique patterns of direction-specific drift while variability remains stable. As subjects were upright during the entire experiment and as drift persisted over several blocks, sensory adaptation seems unlikely. We therefore favor a central origin of this kind of drift.

Is complete surgical resection of stage 4 neuroblastoma a prerequisite for optimal survival or may >95 % tumour resection suffice?

Numerous studies have shown that for optimal survival in localized International Neuroblastoma Staging System stage 1-3 neuroblastoma, complete tumour resection (CR, macroscopic total tumour removal) is usually mandatory. In contrast, it is conceivable that in stage 4 disseminated disease, less extensive surgery [gross total resection (GTR), >95 % tumour removal] may suffice. This review shows substantial survival benefit in studies reporting on stage 4 patients undergoing CR, but also in studies reporting on patients undergoing GTR. Comparison between these studies is severely hampered by treatment heterogeneity. We found only four studies that explicitly compared survival between patients undergoing either CR or GTR. Two of these studies showed favourable results for patients treated with CR, while the other two did not show differences in survival.

The bedside examination of the vestibulo-ocular reflex (VOR): an update.

Diagnosing dizzy patients remains a daunting challenge to the clinician in spite of modern imaging and increasingly sophisticated electrophysiological testing. Here we review the major bedside tests of the vestibulo-ocular reflex and how, when combined with a proper examination of the other eye movement systems, one can arrive at an accurate vestibular diagnosis.

Defining disease status in gastroenteropancreatic neuroendocrine tumors: Choi-criteria or RECIST?

PURPOSE: Adequate monitoring of changes in tumor load is fundamental for the assessment of the course of disease and response to treatment. There is an ongoing debate on the utility of RECIST v1.1 in gastroenteropancreatic neuroendocrine tumors (GEP-NETs). METHODS: In this retrospective real-life cohort study, Choi-criteria were compared with RECIST v1.1. The agreement between both criteria and the association with survival endpoints were evaluated. RESULTS: Seventy-five patients were included with a median follow-up of 35 months (range 8-53). Median progression-free survival (mPFS) according to RECIST v1.1 was 15 months (range 2-50) compared to 14 months (range 2-50) in Choi. According to RECIST, 33 (44%) patients were classified as having stable disease (SD), 40 (53%) as progressive disease (PD) and two (3%) patients as partial response (PR), compared to 9 (12%) patients classified as SD, 50 (67%) as PD and 16 (21%) as PR according to Choi-criteria. Overall concordance between the criteria was moderate (Cohen's Kappa = 0.408, p < 0.001) and agreement varied between 57 and 69% at each consecutive scan (p < 0.001). Survival analysis showed significant differences in overall survival (OS) for RECIST v1.1 categories PD and non-PD (log-rank p = 0.02), however, in Choi no significant differences in OS were found (p = 0.27). CONCLUSION: RECIST v1.1 had a better clinical utility and prognostic value compared to Choi-criteria. Still, RECIST were also not sufficient to adequately predict OS. This outlines the need for new tools that provides accurate information on the disease course and treatment response to support precise prognostication in patients with GEP-NETs.

Quality of life after esophageal replacement in children.

PURPOSE: Assessing quality of life (QoL) after esophageal replacement (ER) for long gap esophageal atresia (LGEA). METHODS: All patients after ER for LGEA with gastric pull-up (GPU n = 9) or jejunum interposition (JI n = 14) at the University Medical Center Groningen and Utrecht (1985-2007) were included. QoL was assessed with 1) gastrointestinal-related QoL using the Gastrointestinal Quality of Life Index (GIQLI)), 2) general QoL (Child Health questionnaire CHF87-BREF (children)/World Health Organization questionnaire WHOQOL-BREF (adults)), and 3) health-related QoL (HRQoL) (TNO AZL TACQoL/TAAQoL). Association of morbidity (heartburn, dysphagia, dyspnea on exertion, recurrent cough) and (HR)QoL was evaluated. RESULTS: Six patients after GPU (75%) and eight patients after JI (57%) responded to the questionnaires (mean age 15.7, SD 5.9, 12 male, two female). Mean gastrointestinal, general and health-related QoL total scores of the patients were comparable to healthy controls. However, young adults reported a worse physical functioning (p = 0.02) but better social functioning compared to peers (p = 0.01). Morbidity was not associated with significant differences in (HR)QoL. CONCLUSIONS: With the current validated QoL most patients after ER with GPU and JI for LGEA have normal generic and disease specific QoL scores. Postoperative morbidity does not seem to influence (HR)QoL. TYPE OF STUDY: Prognosis Study. LEVEL OF EVIDENCE: III.

Prolonged antibiotic treatment does not prevent intra-abdominal abscesses in perforated appendicitis.

BACKGROUND: Children with perforated appendicitis have a relatively high risk of intra-abdominal abscesses. There is no evidence that prolonged antibiotic treatment after surgery reduces intra-abdominal abscess formation. We compared two patient groups with perforated appendicitis with different postoperative antibiotic treatment protocols. METHODS: We retrospectively reviewed patients younger than age 18 years who underwent appendectomy for perforated appendicitis at two academic hospitals between January 1992 and December 2006. Perforation was diagnosed during surgery and confirmed during histopathological evaluation. Patients in hospital A received 5 days of antibiotics postoperatively, unless decided otherwise on clinical grounds. Patients in hospital B received antibiotics for 5 days, continued until serum C-reactive protein (CRP) was <20 mg/l. Univariate logistic regression analysis was performed on intention-to-treat basis. p < 0.05 was considered significant. RESULTS: A total of 149 children underwent appendectomy for perforated appendicitis: 68 in hospital A, and 81 in hospital B. As expected, the median (range) use of antibiotics was significantly different: 5 (range, 1-16) and 7 (range, 2-32) days, respectively (p < 0.0001). However, the incidence of postoperative intra-abdominal abscesses was similar (p = 0.95). Regression analysis demonstrated that sex (female) was a risk factor for abscess formation, whereas surgical technique and young age were not. CONCLUSIONS: Prolonged use of antibiotics after surgery for perforated appendicitis in children based on serum CRP does not reduce postoperative abscess formation.

Penlight-cover test: a new bedside method to unmask nystagmus.

BACKGROUND: Most patients with acute vestibular syndrome have vestibular neuritis or labyrinthitis. Some harbour strokes that can only be differentiated on the basis of subtle eye movement findings, including nystagmus. Peripheral nystagmus should be enhanced by removal of visual fixation. Current bedside methods for removing fixation require expensive equipment or technical skill not routinely available. We sought to test a new method for blocking fixation. METHODS: Proof-of-concept study for a new bedside oculomotor diagnostic test using an established physiological measurement of eye movements (electro-oculography (EOG)) as the reference standard. We sampled unselected patients undergoing caloric testing (surrogate model for neuritis) in an academic vestibular clinic. During the brief (30-60 s) decay phase of caloric-induced peripheral vestibular nystagmus, we shone a penlight in the left eye while intermittently occluding the right. We assessed nystagmus intensity (slow-phase velocity) clinically in all subjects and quantified change in two exemplar cases. RESULTS: Caloric responses frequently decayed before the test was complete, and artefacts rendered many EOGs uninterpretable during the short decay period. A clinically evident increase in nystagmus was seen 18 times in 10 patients and corroborated by EOG in 15. In quantified cases, slow-phase velocity increased as expected (mean change +42%) with fixation blocked. CONCLUSION: The penlight-cover test could offer a low-cost, simple means of disrupting visual fixation in clinical settings where differentiating peripheral from central vestibular disorders is crucial, such as the emergency department. Prospective studies are needed to determine the test's utility for excluding dangerous central causes among patients with suspected peripheral lesions.

Gaze fixation deficits and their implication in ataxia-telangiectasia.

BACKGROUND AND AIMS: Ataxia-telangiectasia (A-T) is an autosomal recessive disorder characterised by progressive neurological deficits, including prominent ocular motor dysfunction. Unstable fixation often leads to difficulty reading and blurred vision. Here we characterise the disturbance of visual fixation in A-T. METHODS: Eye movements were recorded from 13 A-T patients (with dual search coils in five patients and video oculography in seven) during attempted fixation. RESULTS: Two abnormalities--nystagmus and saccadic intrusions--were common. Horizontal, vertical and torsional nystagmus was present in straight ahead (spontaneous nystagmus) and eccentric gaze (gaze evoked nystagmus). In eight patients the horizontal nystagmus changed directions--periodic alternating nystagmus (PAN). Two types of saccadic intrusions were seen--micro-saccadic oscillations (SO) and square wave saccadic intrusions (SWSI). SO were small amplitude (0.1-0.9 degrees) and high frequency (14-33 Hz) back to back horizontal saccades. SWSI ranged between 1 degree and 18 degrees (median 3 degrees) with an intersaccadic interval ranging between 50 and 800 ms (median 300 ms). The potential impact of abnormal gaze stabilisation on vision was quantified. DISCUSSION: Degeneration of cerebellar Purkinje neurons disinhibit the caudal fastigial oculomotor region (FOR) and vestibular nuclei (VN). Disinhibition of VN can cause nystagmus, including PAN, while disinhibition of FOR can affect saccade generating mechanisms, leading to SWSI and SO.

Irregularity distinguishes limb tremor in cervical dystonia from essential tremor.

INTRODUCTION: Patients with cervical dystonia (CD) often have limb tremor that is clinically indistinguishable from essential tremor (ET). Whether a common central mechanism underlies the tremor in these conditions is unknown. We addressed this issue by quantifying limb tremor in 19 patients with CD and 35 patients with ET. METHOD: Postural, resting and kinetic tremors were quantified (amplitude, mean frequency and regularity) using a three-axis accelerometer. RESULTS: The amplitude of limb tremor in ET was significantly higher than in CD, but the mean frequency was not significantly different between the groups. The cycle-to-cycle variability of the frequency (ie the tremor irregularity), however, was significantly greater (approximately 50%) in CD. Analysis of covariance excluded the possibility that the increased irregularity was related to the smaller amplitude of tremor in CD (ANCOVA: p = 0.007, F = 5.31). DISCUSSION: We propose that tremor in CD arises from oscillators with different dynamic characteristics, producing a more irregular output, whereas the tremor in ET arises from oscillators with similar dynamic characteristics, producing a more regular output. We suggest that variability of tremor is an important parameter for distinguishing tremor mechanisms. It is possible that changes in membrane kinetics based on the pattern of ion channel expression underlie the differences in tremor in some diseases.

Minimally invasive pediatric surgery: Increasing implementation in daily practice and resident's training.

BACKGROUND: In 1998, the one-year experience in minimally invasive abdominal surgery in children at a pediatric training center was assessed. Seven years later, we determined the current status of pediatric minimally invasive surgery in daily practice and surgical training. METHODS: A retrospective review was undertaken of all children with intra-abdominal operations performed between 1 January 2005 and 31 December 2005. RESULTS: The type of operations performed ranged from common interventions to demanding laparoscopic procedures. 81% of all abdominal procedures were performed laparoscopically, with a complication rate stable at 6.9%, and conversion rate decreasing from 10% to 7.4%, compared to 1998. There were six new advanced laparoscopic procedures performed in 2005 as compared to 1998. The children in the open operated group were significantly smaller and younger than in the laparoscopic group (p < 0.001 and p = 0.001, respectively). The majority (64.2%) of the laparoscopic procedures were performed by a trainee. There was no difference in the operating times of open versus laparoscopic surgery, or of procedures performed by trainees versus staff surgeons. Laparoscopy by trainees did not have a negative impact on complication or conversion rates. CONCLUSIONS: Laparoscopy is an established approach in abdominal procedures in children, and does not hamper surgical training.

The laparoscopic approach toward hyperinsulinism in children.

Hyperinsulinemic hypoglycemia (HH) in children requiring surgery is rare. Early HH can be the result of focal or diffuse pancreatic pathology. A number of genetic abnormalities in early HH have been identified, but in the majority of patients no abnormality is found. The sporadic focal and diffuse forms as well the autosomal recessive form are particularly therapy-resistant and demand for early surgery. Preoperative discrimination between focal and diffuse disease in early HH is difficult. 18 F DOPA PET in combination with CT is promising as is laparoscopic exploration of the pancreas. Frozen section biopsy analysis has not been uniformly beneficial. If macroscopically no focal lesion is found, limited laparoscopic distal pancreatectomy provides tissue for definitive pathologic examination. Subsequent near total laparoscopic spleen-saving pancreatectomy surgery is not particularly difficult. Later HH may occur in the context of the MEN-1 syndrome and is then multifocal in nature. In MEN-1 patients, a distal spleen-saving pancreatectomy with enucleation of lesions in the head seems justified. Insulin-producing lesions in non-MEN-1 patients should be enucleated. There should always be a suspicion of malignancy. Also, in older children, surgery for hyperinsulinism should be performed laparoscopically.

Thoracoscopic tracheoaortopexia for the treatment of life-threatening events in tracheomalacia.

BACKGROUND: Life-threatening events resulting from tracheomalacia are a well-known complication of infants with esophageal atresia. Aortopexy is accepted as the most effective method for managing severe life-threatening and localized tracheomalacia with a success rate of 85% to 90%. Since the advent of minimally invasive surgery (MIS), the procedure also can be performed using thoracoscopic MIS. METHODS: Between January 2002 and November 2005, six children with esophageal atresia were treated using MIS for life-threatening events attributable to tracheomalacia. RESULTS: The patients tolerated the thoracoscopic procedure well, and all tracheoaortopexies could be performed thoracoscopically. There were two recurrences, which could be treated using thoracoscopy. After a follow-up period of 27 months (range, 10-45 months), all the patients are doing well and have had no more life-threatening events. CONCLUSIONS: Although this is the largest thoracoscopic series to date, the series is too small for any conclusions yet to be drawn. Thoracoscopic tracheoaortopexia is feasible and offers the advantages of MIS.

Duhamel procedure: a comparative retrospective study between an open and a laparoscopic technique.

BACKGROUND: Few studies are available comparing open with laparoscopic treatment of Hirschsprung's disease. This study compares a laparoscopic series of 30 patients with a historical open series of 25 patients. METHODS: The charts of all patients having had a Duhamel procedure in the period from June 1987 through July 2003 were retrospectively reviewed. Open procedures were performed until March 1994. Patients with extended aganglionosis, pre-Duhamel ostomy, or syndrome were excluded from the study. End points were intraoperative complications, postoperative complications, time to first feeding, hospital stay, and outcome at follow-up such as stenosis, enterocolitis, constipation, fecal incontinence, and enuresis. RESULTS: Twenty-five patients had an open Duhamel (OD) and 30 had a laparoscopic one (LD). There were no differences in patient characteristics and there were no intraoperative complications in either group. Time to first oral feeds was significantly longer in the OD group as was the duration of hospital stay. No significant differences at follow-up were observed but there was a tendency for a higher enterocolitis rate in the LD group. In contrast, the adhesive obstruction and enuresis rates were higher in the OD group. Cosmetic results were superior in the LD group. CONCLUSIONS: Except for a significantly shorter hospital stay and shorter time to first oral feeds in favor of LD, no significant differences could be observed. The cosmetic result was not an end point but there was no doubt that it was better in the LD group. Although not statistically significant different, there were no adhesive bowel obstructions in the LD group compared with 3 of 25 in the OD group. Fecal incontinence was not encountered in either group.

Construct validity of the LapSim: can the LapSim virtual reality simulator distinguish between novices and experts?

BACKGROUND: Virtual reality simulators may be invaluable in training and assessing future endoscopic surgeons. The purpose of this study was to investigate if the results of a training session reflect the actual skill of the trainee who is being assessed and thereby establish construct validity for the LapSim virtual reality simulator (Surgical Science Ltd., Gothenburg, Sweden). METHODS: Forty-eight subjects were assigned to one of three groups: 16 novices (0 endoscopic procedures), 16 surgical residents in training (>10 but <100 endoscopic procedures), and 16 experienced endoscopic surgeons (>100 endoscopic procedures). Performance was measured by a relative scoring system that combines single parameters measured by the computer. RESULTS: The higher the level of endoscopic experience of a participant, the higher the score. Experienced surgeons and surgical residents in training showed statistically significant higher scores than novices for both overall score and efficiency, speed, and precision parameters. CONCLUSIONS: Our results show that performance of the various tasks on the simulator corresponds to the respective level of endoscopic experience in our research population. This study demonstrates construct validity for the LapSim virtual reality simulator. It thus measures relevant skills and can be integrated in an endoscopic training and assessment program.

[Invagination in children: not always ileocaecal]. / Invaginaties bij kinderen: niet altijd ileocoecaal.

Three patients, two girls aged 10 and a boy aged 11, suffered from secondary intussusception. Two of the cases were mistakenly managed as an idiopathic or classic intussusception. Hydrostatic reduction with a contrast enema was thought to be successful when retrograde influx in the ileum was seen. As the intussusception recurred, a diagnostic laparoscopy was performed followed by laparotomy and surgical treatment. In both cases an ileo-ileal intussusception was found. In one case the lead point was a malignant lymphoma, in the other case probably an area of vasculitis associated with Henoch Schönlein purpura. The enema had only repositioned the ileocolic part of the intussusception. In the third patient, the ileo-ileal intussusception resolved spontaneously. Due to the location of the intus-susception, a lead point was suspected and a laparoscopy was performed. A Meckel's diverticulum was found and resected. The importance of looking for a lead point is emphasized when dealing with an intussusception in children over the age of 3, or with evidence of underlying disease. In such cases, the relative value of a contrast enema for diagnosis and reposition is emphasised. There should be a low threshold for further investigation, including diagnostic laparoscopy.