Evaluation methods and impact of simulation-based training in pediatric surgery: a systematic review.

PURPOSE: The aim of this study was to identify (1) the type of skill evaluation methods and (2) how the effect of training was evaluated in simulation-based training (SBT) in pediatric surgery. METHODS: Databases of PubMed, Cochrane Library, and Web of Science were searched for articles published from January 2000 to January 2017. Search concepts of Medical Subject Heading terms were "surgery," "pediatrics," "simulation," and "training, evaluation." RESULTS: Of 5858 publications identified, 43 were included. Twenty papers described simulators as assessment tools used to evaluate technical skills. Reviewers differentiated between experts and trainees using a scoring system (45%) and/or a checklist (25%). Simulators as training tools were described in 23 papers. While the training's effectiveness was measured using performance assessment scales (52%) and/or surveys (43%), no study investigated the improvement of the clinical outcomes after SBT. CONCLUSION: Scoring, time, and motion analysis methods were used for the evaluation of basic techniques of laparoscopic skills. Only a few SBT in pediatric surgery have definite goals with clinical effect. Future research needs to demonstrate the educational effect of simulators as assessment or training tools on SBT in pediatric surgery.

Clinical Usefulness of Serum Krebs von den Lungen-6 for Detecting Chronic Aspiration in Children with Severe Motor and Intellectual Disabilities.

OBJECTIVE: To determine whether the serum level of Krebs von den Lungen-6 (KL-6), a circulating high-molecular weight glycoprotein and a diagnostic biomarker of interstitial lung diseases, is a clinically useful biomarker for detecting chronic aspiration in children with severe motor and intellectual disabilities (SMIDS). STUDY DESIGN: Children with SMIDS undergoing videofluorography for assessment of dysphagia were prospectively evaluated. Based on the videofluorography results, the participants were classified into aspiration and non-aspiration groups. Age, sex, white blood cell count, and serum levels of C-reactive protein, lactate dehydrogenase, albumin, and KL-6 were compared between the 2 groups. Binary logistic regression was performed to identify factors independently associated with the presence of aspiration. RESULTS: A total of 66 patients participated in this study, 37 who were classified as the aspiration group and 29 as the non-aspiration group. The serum KL-6 level in the aspiration group was significantly higher than that in the non-aspiration group (median, 344 U/mL vs 207 U/mL, P < .01). Logistic regression modeling showed that the number of prescribed antiepileptic drugs (OR, 1.978; 95% CI, 1.217, 3.214; P < .01) and serum KL-6 level (OR, 1.012; 95% CI, 1.005, 1.019; P < .01) were independent predictors of aspiration. CONCLUSIONS: The study demonstrated that the KL-6 level is significantly higher in children with SMIDS who aspirate than in those who do not. KL-6 shows promise as a biomarker for chronic lung disease due to aspiration in these children.

Comparison between serum free triiodothyronine levels and body fluid distribution in hemodialysis patients.

AIM: Low free triiodothyronine (fT3) has been associated with the presence of malnutrition-inflammation syndrome in patients with end-stage renal disease (ESRD) and decreased overall survival in ESRD. Since thyroid hormone has a particular effect on body fluid status, we hypothesized that hemodialysis patients with low-T3 syndrome might have interstitial edema. In this study, we examined the relationship between levels of thyroid hormone and body composition parameters in Japanese hemodialysis patients. METHODS: The subjects were 52 patients on maintenance hemodialysis. Serum levels of thyroid hormone and atrial natriuretic peptide (hANP) were measured. Body composition parameters were measured using a bioimpedance body composition analyzer. RESULTS: Serum fT3 had positive correlations with body mass index (BMI), body fat mass (BFM), total body water (TBW) and intracellular water (ICW), and negative correlations with the ratio of extracellular water to total body water (ECW/TBW) and hANP. There were no correlations between serum fT4 and any body composition parameter. The 49 patients with data at baseline and after 1 year were divided into groups with increased (n = 33) and decreased (n = 16) fT3 after 1 year. ΔBMI and ΔBFM were significantly lower and ΔTBW, ΔICW, ΔECW and ΔECW/TBW (changes over 1 year from baseline) were significantly higher in patients with decreased fT3 compared to those with increased fT3. There was no significant difference in ΔhANP or Δcardiothoracic ratio between the two groups. CONCLUSION: These results show that a decrease in fT3 might be associated with emaciation and interstitial edema in Japanese hemodialysis patients.

Heterogeneity of posterior limbic perfusion in very early Alzheimer's disease.

PURPOSE: This study was designed to quantify the heterogeneity of cerebral perfusion on SPECT images in elderly controls and Alzheimer's disease (AD) patients in mild stage using a three-dimensional fractal analysis (3D-FA). MATERIAL AND METHOD: Seventy-five patients with possible and probable AD based on the NINCDS/ADRDA criteria, and thirty-one elderly controls underwent 99mTc-HMPAO SPECT scanning. Dementia severity was assessed using the clinical dementia rating (CDR). Patients with CDR scores of 0.5 (n=33) were classified as "very early" and those with CDR 1 (n=42) as "early". We delineated the SPECT images using 2 cutoffs (35% and 50% cutoffs of the maximal voxel radioactivity) and measured the number of voxels in the areas included by the contours obtained with each cutoff level. The fractal dimension (FD) was calculated by relating the logarithms of cutoff level and the number of voxels. Posterior limbic images were reconstructed at 30 degrees positive to the coronal plane, and posterior limbic FD was calculated. RESULT: Posterior limbic FD for early AD, very early AD, and control groups were 1.03+/-0.16, 1.02+/-0.17, and 0.87+/-0.14 (P=0.001 versus early AD group, P=0.001 versus very early AD). Use of the posterior limbic FD and the ratio of posterior limbic FD to total FD separated very early AD patients from controls with a sensitivity of 76% and a specificity of 81%. CONCLUSION: 3D-FA indicated significant differences in the heterogeneity of CBF distribution between patients with AD in mild stage and elderly controls. Posterior limbic FD may be useful for easily and objectively distinguishing patients with very early AD from aging people.

Thallium-201 scintigraphy in bone and soft-tissue tumors: a comparison of dynamic, early and delayed scans.

OBJECTIVE: It has been reported that delayed scan of thallium-201 (201Tl) scintigraphy is useful for differentiating malignant tumors from benign lesions and for evaluating treatment response. However, physiological muscle uptake which usually increases in delayed scans, often makes it difficult to evaluate 201Tl uptake and its washout in bone and soft-tissue tumors. The purpose of this study was to evaluate whether the delayed scan is necessary and whether a dynamic scan is useful in the evaluation of bone and soft-tissue tumors. METHODS: We studied 175 cases of bone and soft-tissue tumors (malignant 45, benign 130). Dynamic scans were acquired every 5 seconds for 10 minutes after 201Tl injection, and time activity curves (TACs) were generated by adaptive smoothing methods. Early and delayed scans were acquired at 10-15 minutes and 2 hours after injection. 201Tl images were visually interpreted and the radioactivity count ratio (T/N) of tumors to normal tissues and washout rate [WR = (early T/N - delayed T/N)/early T/N] were defined. RESULTS: When there were no 201Tl uptake in dynamic (n = 67) and early scans (n = 68), no tumor uptake was also appreciated in delayed scans, and all but two cases of negative scans were benign. In 107 lesions, although there were significant differences in T/Ns between malignant and benign lesions both on early scans (2.84 +/- 1.45 vs. 2.05 +/- 1.13, p < 0.05) and delayed scans (2.17 +/- 1.03 vs. 1.58 +/- 0.64, p < 0.05), there was a substantial overlap. The T/Ns decreased in delayed scans (i.e., WR > 0) in 100 of 107 cases due to increase of surrounding muscle uptake, and there was no difference in WR between malignant tumors and benign lesions (0.21 +/- 0.14 vs. 0.19 +/- 0.14). CONCLUSIONS: For evaluating bone and soft-tissue tumors, delayed scan had little clinical usefulness and it may be time consuming. Dynamic scan would be useful for demonstrating the differences between tumor blood flow and 201Tl uptake in tumors.

Usefulness of brain SPECT to evaluate brain tolerance and hemodynamic changes during temporary balloon occlusion test and after permanent carotid occlusion.

UNLABELLED: The purpose of this study was to evaluate the usefulness of SPECT during temporary carotid balloon occlusion testing and to evaluate the changes in regional cerebral blood flow (CBF) and regional cerebral perfusion reserve (CPR) after permanent carotid occlusion. METHODS: Temporary balloon occlusion testing was performed on 40 patients (24 head and neck tumors, 16 aneurysms). During the balloon occlusion (total time, 30 min), (99m)Tc-ethylcysteinate dimer (ECD) was injected intravenously about 5 min before balloon deflation, followed by SPECT data acquisition. SPECT images were visually evaluated, and the severity of hypoperfusion on the occluded side was classified using 4 grades (normal, mild, moderate, and severe). The count ratio of the occluded side to the contralateral side (L/N ratio) was also analyzed. In 7 patients who subsequently underwent permanent carotid occlusion, CBF and CPR were quantitatively assessed using (133)Xe inhalation dynamic SPECT at rest and after acetazolamide (ACZ) enhancement (CPR was defined as the percentage increase in CBF after ACZ), and the patients were followed up periodically. RESULTS: SPECT after temporary occlusion showed moderate or severe hypoperfusion in 12 patients, whereas neurologic deterioration was observed in only 4 patients. The L/N ratios were 0.96 +/- 0.03 in normal perfusion (13 patients), 0.93 +/- 0.03 in mild hypoperfusion (15 patients), 0.83 +/- 0.03 in moderate hypoperfusion (10 patients) and 0.66 +/- 0.09 in severe hypoperfusion (2 patients) (P < 0.0001). In the 7 patients who underwent permanent carotid occlusion, CPR decreased after surgery (35% +/- 7% vs. 7% +/- 14%, P < 0.05), even though the resting CBF did not change (54 +/- 8 mL/100 g/min vs. 52 +/- 6 mL/100 g/min, not statistically significant). The steal phenomenon (rCPR < 0%) was observed in 3 patients, 1 of whom experienced transient hemiparesis when blood pressure dropped soon after surgery. On follow-up, the decreased CPR gradually improved and no infarction developed. CONCLUSION: SPECT is useful to detect cerebral hypoperfusion during carotid occlusion. Assessment of CPR is recommended to predict the potential risk of postsurgical complications and to follow up patients after permanent carotid occlusion.

Ischemic "memory image" in acute myocardial infarction of 123I-BMIPP after reperfusion therapy: a comparison with 99mTc-pyrophosphate and 201Tl dual-isotope SPECT.

Ischemic "memory image" is a phenomenon of 123I-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) in which an area at risk of acute myocardial infarction (AMI), could be detected as a defect in a couple of weeks even after successful reperfusion therapy. The purpose of this study was to clarify the incidence of the ischemic "memory image" of 123I-BMIPP in patients with AMI by comparing 99mTc-PYP and 201Tl dual-isotope SPECT. Materials consisted of 14 patients with successfully reperfused AMI and 20 patients with old myocardial infarction (OMI). All AMI patients underwent PYP/Tl dual-isotope SPECT within 1 week after the onset of AMI, and BMIPP SPECT was performed within 1 week after the PYP/Tl dual-isotope SPECT. The extent and severity of the defect of BMIPP and Tl were visually scored into four grades: 0 = no defect to 3 = large or severe defect. These scores were compared. PYP positive AMI lesions were concordant with BMIPP defects (13/14). In AMI, both the extent and severity scores of BMIPP were higher than 201Tl (p < 0.001). Differences (BMIPP - Tl) of extent and severity scores were greater in AMI than in OMI (p < 0.001). In conclusion, the ischemic "memory image" obtained by means of the BMIPP is a common phenomenon (13/14) in AMI, and helpful in evaluating the area at risk.

Acute right heart failure and achalasia-like syndrome in a patient with limited cutaneous systemic sclerosis and primary biliary cirrhosis.

We report a case of a 63-year-old woman who developed acute right heart failure and an achalasia-like syndrome with limited cutaneous systemic sclerosis (lcSSc) and primary biliary cirrhosis. Intravenous administration of diuretics improved her acute heart failure. Anti-centromere antibodies and anti-mitochondria antibodies were present. A coronary angiogram and a Swan-Ganz catheter revealed no abnormalities. Thallium-201 scan at rest demonstrated mild perfusion defects in both the apex and the anteroseptal and the inferior myocardium. A cine-esophagram revealed an achalasia-like syndrome. Though rare, physicians should be aware that some patients with lcSSc may develop acute right heart failure or achalasia-like syndrome.

The role of computer-aided 3-dimensional analytic tools and virtual microscopy in the investigation of radiologic-pathologic correlation.

To cope with recent advances in radiologic imaging technology, a corresponding method for pathomorphologic demonstration should be developed to promote better understanding of radiologic-pathologic correlation. We attempted to obtain gross and microscopic images by using a 3-dimensional analytic tool and virtual microscopy and to link these images with multidetector computed tomography images. Surgically resected specimens were sliced to a thickness of 3 mm, and the digital images of each slice were 3-dimensionally reconstructed with RATOC TRI/3D SRF II software. Histology slides were digitized by using virtual microscopy with an Olympus VS-100. We obtained clear gross pathologic images in arbitrary cut sections of organs, and it was possible to rotate these 3-dimensional images at any angle. Furthermore, we created synchronous cut-section movies of computed tomography and gross pathologic images. Subsequently, we switched from these cut-section movies to virtual microscopy images by clicking on the hyperlink button to observe radiologic-pathologic correlation.

Crystal structures of the complexes between vancomycin and cell-wall precursor analogs.

The crystal structures of three vancomycin complexes with two vancomycin-sensitive cell-wall precursor analogs (diacetyl-Lys-D-Ala-D-Ala and acetyl-D-Ala-D-Ala) and a vancomycin-resistant cell-wall precursor analog (diacetyl-Lys-D-Ala-D-lactate) were determined at atomic resolutions of 1.80 A, 1.07 A, and 0.93 A, respectively. These structures not only reconfirm the "back-to-back" dimerization of vancomycin monomers and the ligand-binding scheme proposed by previous experiments but also show important structural features of strategies for the generation of new glycopeptide antibiotics. These structural features involve a water-mediated antibiotic-ligand interaction and supramolecular structures such as "side-by-side" arranged dimer-to-dimer structures, in addition to ligand-mediated and "face-to-face" arranged dimer-to-dimer structures. In the diacetyl-Lys-D-Ala-D-lactate complex, the interatomic O...O distance between the carbonyl oxygen of the fourth residue of the antibiotic backbone and the ester oxygen of the D-lactate moiety of the ligand is clearly longer than the corresponding N-H...O hydrogen-bonding distance observed in the two other complexes due to electrostatic repulsion. In addition, two neighboring hydrogen bonds are concomitantly lengthened. These observations provide, at least in part, a molecular basis for the reduced antibacterial activity of vancomycin toward vancomycin-resistant bacteria with cell-wall precursors terminating in -D-Ala-D-lactate.

Heterogeneity of cerebral blood flow in frontotemporal lobar degeneration and Alzheimer's disease.

This study was designed to quantify the heterogeneity on cerebral blood flow single-photon emission tomography (SPET) images in frontotemporal lobar degeneration (FTLD) and Alzheimer's disease (AD) using a three-dimensional fractal analysis. Twenty-one FTLD patients, 21 AD patients and 11 healthy controls underwent technetium-99m hexamethylpropylene amine oxime SPET scanning. Patients with FTLD and AD matched for sex, age and the severity of dementia as estimated with the Clinical Dementia Rating and were determined to be in the early stage of illness. We delineated the SPET images using a 35% cut-off and a 50% cut-off of the maximal voxel radioactivity and measured the number of voxels included in the contours of two different cut-offs. The fractal dimension (FD) was calculated by relating the logarithms of the cut-offs and the numbers of voxels, and it was defined as the heterogeneity of the cerebral perfusion. We divided the SPET images into two sets, anterior and posterior, with equal numbers of coronal SPET slices. We calculated total FD, anterior FD and posterior FD for total, anterior and posterior SPET images. Anterior FDs for FTLD and AD were 1.55 +/- 0.34 and 1.24 +/- 0.19 (P = 0.0002). The ratios of anterior to posterior FD for FTLD and AD were 1.81 +/- 0.41 and 1.32 +/- 0.14 (P < 0.0001). Use of the anterior FD and the ratio of anterior to posterior FD separated FTLD patients from AD patients and controls with a sensitivity of 85.7% and a specificity of 93.8%. Anterior FD and the ratio of anterior to posterior FD may be useful in distinguishing FTLD from AD.