Effect of cranial entry site on the rate of proximal catheter misplacement in ventriculoperitoneal shunt insertion.

OBJECTIVE: The insertion of a ventriculoperitoneal shunt (VPS) is a common neurosurgical procedure, but the optimal entry site of the ventricular catheter is still under debate. In this study, the authors compare the parietal (Keen's) and frontal (Kocher's) entry sites in terms of the rate of revision surgery due to ventricular catheter misplacement, VPS dysfunction, and VPS infection. METHODS: The authors retrospectively analyzed the data on consecutive adults (age ≥ 18 years) who had undergone primary VPS insertion between 2010 and 2020 at two neurosurgical centers. One center regularly inserts the ventricular catheter frontally (frontal group); the other center, parietally (parietal group). The primary outcome of interest was the rate of ventricular catheter misplacement necessitating revision surgery. Secondary outcomes were functional outcome as measured by the modified Rankin Scale (mRS), rate of revision surgery for VPS dysfunction and infection, as well as early (≤ 30 days) and late (> 30 days) mortality rates. Propensity score matching was performed based on baseline variables, such as normal pressure hydrocephalus, postinfectious hydrocephalus, and idiopathic intracranial hypertension, which were identified as predictors of ventricular catheter misplacement using logistic regression analysis. RESULTS: Among 539 consecutive patients, 301 (55.8%) were in the frontal group and 238 (44.2%) in the parietal group. Postoperative rates of revision surgery due to misplacement were comparable in the two catheter entry site groups (frontal 14 [4.7%] vs parietal 11 [4.6%], p = 0.987). Rates of revision surgery for VPS dysfunction (14 [4.7%] vs 10 [4.2%], respectively, p = 0.802) and infection (22 [7.3%] vs 10 [4.2%], p = 0.13) exhibited no significant differences. Favorable functional outcomes (mRS score ≤ 2; 164 [76.3%] vs 174 [79.5%], respectively, p = 0.058) and early mortality rates (5 [1.7%] vs 6 [2.5%], p = 0.483) were similar between the groups. After propensity score matching, the primary and secondary outcome measures remained comparable between the groups. CONCLUSIONS: The entry site of the ventricular catheter in VPS surgery does not seem to affect proximal revision rates. Further, revision rates due to VPS dysfunction, VPS infection, and morbidity were comparable as well.

Uncovering developmental time and tempo using deep learning.

During animal development, embryos undergo complex morphological changes over time. Differences in developmental tempo between species are emerging as principal drivers of evolutionary novelty, but accurate description of these processes is very challenging. To address this challenge, we present here an automated and unbiased deep learning approach to analyze the similarity between embryos of different timepoints. Calculation of similarities across stages resulted in complex phenotypic fingerprints, which carry characteristic information about developmental time and tempo. Using this approach, we were able to accurately stage embryos, quantitatively determine temperature-dependent developmental tempo, detect naturally occurring and induced changes in the developmental progression of individual embryos, and derive staging atlases for several species de novo in an unsupervised manner. Our approach allows us to quantify developmental time and tempo objectively and provides a standardized way to analyze early embryogenesis.

EmbryoNet: using deep learning to link embryonic phenotypes to signaling pathways.

Evolutionarily conserved signaling pathways are essential for early embryogenesis, and reducing or abolishing their activity leads to characteristic developmental defects. Classification of phenotypic defects can identify the underlying signaling mechanisms, but this requires expert knowledge and the classification schemes have not been standardized. Here we use a machine learning approach for automated phenotyping to train a deep convolutional neural network, EmbryoNet, to accurately identify zebrafish signaling mutants in an unbiased manner. Combined with a model of time-dependent developmental trajectories, this approach identifies and classifies with high precision phenotypic defects caused by loss of function of the seven major signaling pathways relevant for vertebrate development. Our classification algorithms have wide applications in developmental biology and robustly identify signaling defects in evolutionarily distant species. Furthermore, using automated phenotyping in high-throughput drug screens, we show that EmbryoNet can resolve the mechanism of action of pharmaceutical substances. As part of this work, we freely provide more than 2 million images that were used to train and test EmbryoNet.

Prophylactic antithrombotic management in adult and pediatric kidney transplantation: A systematic review and meta-analysis.

BACKGROUND: RGT is a major cause for early graft loss after KTx. Although evidence-based recommendations are lacking, aP is often used to prevent RGT. This systematic review aimed to determine the effectiveness and safety of aP in adult and pediatric KTx recipients. METHODS: MEDLINE, EMBASE, Cochrane Controlled Trials Register, conference proceedings, and electronic databases for trial registries were searched for eligible studies using search terms relevant to this review (April 21, 2020). The systematic review was carried out following the recommendations of the Cochrane Collaboration and the Prefered Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement. RESULTS: Twelve studies comprising 2370 patients (adult = 1415, pediatric = 955) were included, of which three were RCTs. The overall risk for developing RGT was lower in the group with aP compared with the control group (RR 0.24, 95% confidence interval 0.12-0.49). The antithrombotic drugs used were heparin (7/12), acetylsalicylic acid (2/12), a combination of both (2/12), and dipyridamole (1/12) with a high variability in timing, dosing, and mode of application. Adverse effects were reported rarely, with minor bleeding as the main complication. The non-randomized studies had significant risks of bias in the domains of patient selection, confounder, and measurement of outcomes. CONCLUSION: Based on pooled analysis, aP seems to reduce the risk of RGT in KTx. However, the reliability of these results is limited, as the quality of the available studies is poor and information on adverse effects associated with aP is scarce. Additional high-quality research is urgently needed to provide sufficient data supporting the use of aP in KTx.