A Novel Technique for Risk Calculation of Anastomotic Leakage after Thoracoscopic Repair for Esophageal Atresia with Distal Fistula

PURPOSE: This study was designed to determine the risk of anastomotic leakage after thoracoscopic repair for esophageal atresia by digitally measuring the length of the proximal esophagus and distance of carina to proximal esophagus. METHODS: With the use of Picture Archiving and Communication System (PACS), the length of the proximal esophagus from the top of the first thoracic vertebra was measured on the preoperative chest x-ray, as well as the distance from the carina to the proximal esophagus. The chest x-rays of 27 neonates, born with esophageal atresia with distal fistula, were examined. Furthermore, the tapes from the procedures were reviewed. Statistical analysis was performed with the t test for equality of means by using SPSS 12.0.1 for Windows. RESULTS: Both groups were comparable, and there was a statistical significant difference in both length of the proximal esophagus (p < 0.023) and distance of carina to proximal esophagus (p < 0.022) in patients who did and did not leak postoperatively. There seems to be a tendency toward a shorter proximal esophagus in recent years that was not obvious earlier. CONCLUSIONS: The digital measurement of the length of the proximal esophagus (M < 7 mm) and distance of carina to proximal esophagus (M > 13.5 mm) with the use of PACS gives a good risk calculation for postoperative leakage.     

Three‐Dimensional Stereophotogrammetry: A Novel Method in Volumetric Measurement of Infantile Hemangioma

Accurate and objective measurement of volume changes in infantile hemangiomas (IHs) is essential in routine clinical practice and clinical studies, particularly in the changing therapeutic landscape after the discovery of propranolol. Several bedside techniques for volume measurement have been described in the literature, but an objective method of measurement of this variable, dynamic vascular tumor is lacking. Three‐dimensional (3D) phototechnology with data analysis is an up‐and‐coming technique in the objective measurement of facial volume changes. In this pilot study, the usability and clinical relevance of two methods of 3D stereophotogrammetry in the volume measurement of IH were explored.     

Influence of Skull Modeling Approaches on EEG Source Localization

Electroencephalographic source localization (ESL) relies on an accurate model representing the human head for the computation of the forward solution. In this head model, the skull is of utmost importance due to its complex geometry and low conductivity compared to the other tissues inside the head. We investigated the influence of using different skull modeling approaches on ESL. These approaches, consisting in skull conductivity and geometry modeling simplifications, make use of X-ray computed tomography (CT) and magnetic resonance (MR) images to generate seven different head models. A head model with an accurately segmented skull from CT images, including spongy and compact bone compartments as well as some air-filled cavities, was used as the reference model. EEG simulations were performed for a configuration of 32 and 128 electrodes, and for both noiseless and noisy data. The results show that skull geometry simplifications have a larger effect on ESL than those of the conductivity modeling. This suggests that accurate skull modeling is important in order to achieve reliable results for ESL that are useful in a clinical environment. We recommend the following guidelines to be taken into account for skull modeling in the generation of subject-specific head models: (i) If CT images are available, i.e., if the geometry of the skull and its different tissue types can be accurately segmented, the conductivity should be modeled as isotropic heterogeneous. The spongy bone might be segmented as an erosion of the compact bone; (ii) when only MR images are available, the skull base should be represented as accurately as possible and the conductivity can be modeled as isotropic heterogeneous, segmenting the spongy bone directly from the MR image; (iii) a large number of EEG electrodes should be used to obtain high spatial sampling, which reduces the localization errors at realistic noise levels.     

Limitations and caveats of magnetic cell labeling using transfection agent complexed iron oxide nanoparticles

Cell labeling with various types of nanomaterial, such as FDA‐approved iron oxide nanoparticles (IONPs) has become common practice in biomedical research. The low uptake of IONPs stimulates the use of transfection agents (TA), but the effect on stability of the IONPs and their cellular interactions has received minimal attention. In the present study, we evaluated the use of Lipofectamine as a commonly used TA and tested different ratios of TA and IONPs. While the TA–IONP complexes are stable in saline, at a high ratio of TA over IONP, substantial aggregation occurred in serum‐containing media. Even for the highest ratio, TA was unable to completely cover the IONPs, resulting in a net negative charge of all complexes. At high TA–IONP ratios, more complexes remained surface‐associated without internalization, resulting in cell death, while at lower TA–IONP ratios, complexes were more avidly taken up through fluid‐phase pinocytosis and clathrin‐mediated endocytosis. At later time points, the endocytosed complexes accumulated within the lysosomes and affected the appearance of lysosomal structures. The data indicate that TAs should be used with care as, depending on the ratio of TA and IONP, the complexes may aggregate, inducing cell death and preventing internalization. Copyright © 2012 John Wiley & Sons, Ltd.     

How to assess cytotoxicity of (iron oxide‐based) nanoparticles. A technical note using cationic magnetoliposomes

The range of different types of nanoparticles and their biomedical applications is rapidly growing, creating a need to thoroughly examine the effects these particles have on biological entities. One of the most commonly used nanoparticle types is iron oxide nanoparticles, which can be used as MRI contrast agents. The main research topic is the in vitro labeling of cells with iron oxide nanoparticles to render the cells detectable for MRI upon in vivo transplantation. For the correct evaluation of cell function and behavior in vivo, any effects of the nanoparticles on the cells must be completely ruled out. The present work provides a technical note where a detailed overview is given of several assays that could be useful to determine nanoparticle toxicity. The assays described focus on (i) nanoparticle internalization, (ii) immediate cell toxicity, (iii) cell proliferation, (iv) cell morphology, (v) cell functionality and (vi) cell physiology. Potential pitfalls, appropriate controls and advantages/disadvantages of the different assays are given. The main focus of this work is to provide a detailed guide to help other researchers in the field interested in setting up nanoparticle‐toxicity studies. Copyright © 2010 John Wiley & Sons, Ltd.     

Mandibuläre Hypoplasie

In order to restore function and ¶esthetics in mandibular hypoplasia, transplantation of osteochondral grafts and the distraction osteogenesis technique are used alternatively. In a retrospective study the indication, growth and complication rate ¶of osteochondral graft and distraction osteogenesis cases in mandibular hypoplasia were compared. In total, 12 patients (4–14 years old; 7 female, 5 male) with different grades of mandibular hypoplasia received osteochondral grafts (7 costochondral, 5 iliac crest; observation period 4–9 years). In 5 patients (10–12 years old; 1 female, 4 male), distraction osteogenesis was performed (observation period 10 months to 3 1/2 years). In the results, according to the literature, the range of growth after osteochondral grafting varied considerably, approximate normal growth was noticed in only two cases. On the other hand, all patients treated by distraction osteogenesis showed a stable increase of bone length as expected. After osteochondral grafts, adequate growth is to be expected in the minority of cases and it does not seem predictable in individual cases. Therefore, the indication for osteochondral grafts should be restricted to severe hypoplasia, where the local amount of bone does not allow the use of a distraction device, and to cases where support of the mandibula at the skull base is necessary. In all other cases of mandibular hypoplasia in children, distraction osteogenesis should be discussed as the primary option, even if in the long term a second surgical procedure should be necesssary.     

Oocyte insemination with spermatozoa precursors

Since the use of testicular spermatozoa in programs of assisted fertilization proved very successful, attention was focussed on the use of spermatids also carrying 23 chromosomes. Several difficulties became obvious; the first one concerned the recognition of round spermatids. This is a problem which does not concern elongating and elongated cells. The intra-cytoplasmic injection of elongated spermatids resulted in several pregnancies but this is not so for the round ones. Although, in the group of patients in whom only round spermatids are found at the time of the attempt, is to be divided into two categories; patients in whom previous research allowed to find spermatozoa, however few, and patients who never produced spermatozoa at all. This last group is no longer an indication for intracytoplasmic sperm injection procedure unless in the future new culture media allow a maturation into elongated forms.