Improving diagnosis accuracy of brain volume abnormalities during childhood with an automated MP2RAGE-based MRI brain segmentation

Background and purposeIt can be challenging to depict brain volume abnormalities in the pediatric population on magnetic resonance imaging (MRI). The aim of the study was to evaluate the inter-radiologist reliability in brain MRI interpretation, including brain volume assessment and the efficiency of an automated brain segmentation.Materials and methodsWe performed a single-center prospective study including 44 patients aged six months to five years recruited from the University Hospital, having a 1.5 T brain MRI using a MP2RAGE sequence. All MRI were randomly and blindly reviewed by one junior and two senior pediatric radiologists. Inter-observer agreements were assessed using Fleiss’ kappa coefficient. Brain volumetry (total intracranial volume (TIV), brain parenchyma, and cerebrospinal fluid volumes) was estimated using the MorphoBox prototype. Clinical head circumference (HC) and z scores were reported. A Pearson correlation coefficient was calculated between brain volumes with HC.ResultsTwenty-four brain MRI examinations were normal and twenty were pathological. Brain volume abnormalities were poorly detected by junior and senior radiologists: sensitivities 16.67% [confidence interval 4.7–44.8], 33.33% [13–60] and 30.7% [12–58] and specificities 93.75% [79–98], 84.38% [68–93] and 77% [60–88], respectively. Brain volume apart, interobserver kappa coefficients were 0.93 between junior and seniors as well as between seniors. Brain volumes were significantly correlated with HC (P < 0.0001). In patients with normal MRI, brain parenchyma volumes increased regularly with age. Low brain volume was easier to identify with automated quantification.ConclusionBrain volume was poorly appreciated by radiologists. The fully automated brain segmentation used can provide quantitative data to better diagnose, describe, and follow-up brain volume abnormalities.     

Trimethoprim-sulfamethoxazole as de-escalation in ventilator-associated pneumonia: a cohort study subanalysis

European Journal of Clinical Microbiology & Infectious Diseases - This is a subanalysis of a previous study which compared the effectiveness of trimetoprim-sulfametoxazole (TMP-SMX) with all...     

Can autologous thrombin with a rest fraction of ethanol be used safely for activation of concentrated autologous platelets applied on nerves?

The use of concentrated platelet-rich plasma (cPRP) as a source of growth factors is reported to be beneficial for an enhanced osteogenesis in spine surgery. Today both bovine and autologous thrombin is used for activating the platelets and thus releasing the growth factors. In order to prevent transmission of organisms and the development of antibodies, autologous thrombin seems to be the logical choice. However, the preparation of autologous thrombin is cumbersome and consumes a part of the cPRP. In order to overcome this problem, a commercial autologous thrombin kit (activAT, Dideco, a Sorin Group company, Italy) has been developed which produces autologous thrombin out of platelet-poor plasma. A possible disadvantage of this kit could be the rest fraction of 1.18% of ethanol in the platelet gel. In a pig model, the influence of different ethanol concentrations on the ischiadic nerve was studied. The study consisted out of four groups; a control group (n=6), a group with platelet gel 0% ethanol (n=6), a group with platelet gel 1.18% ethanol (n=6) and a group with platelet gel 3.8% ethanol (n=7). In all the groups, the ischiadic nerve was dissected and the myelin sheet opened after which the wound was closed (control group) or one of the three therapies was applied. After 12 h, the animal was sacrificed and the ischiadic nerve was submitted for histological examination. Myelin sheaths appeared normal in all cases. No axonal swelling was observed. No statistically significant differences were observed for neutrophilic and eosinophilic infiltration nor for collagen necrosis between groups. Platelet gel prepared by the use of a commercial autologous thrombin kit and containing 1.18% of ethanol can be safely used on nerves.     

Mechanical thrombectomy in patients with deep venous thrombosis

Purpose: To report our experience with mechanical thrombectomy in proximal deep vein thrombosis (DVT). Methods: Eighteen patients with a mean (± SD) age of 37.6 ± 16.1 years who presented with DVT in the iliac and femoral vein (n = 3), inferior vena cava (n = 5), or inferior vena cava and iliac vein (n = 10), were treated with the Amplatz Thrombectomy Device after insertion of a temporary caval filter. Results: Successful recanalization was achieved in 15 of 18 patients (83%). Overall, the percentage of thrombus removed was 66 ± 29%: 73 ± 30% at caval level and 55 ± 36% at iliofemoral level. Complementary interventions (seven patients) were balloon angioplasty (n = 2), angioplasty and stenting (n = 2), thrombo-aspiration alone (n = 1), thrombo-aspiration, balloon angioplasty, and permanent filter (n = 1), and permanent filter alone (n = 1). There was one in-hospital death. Follow-up was obtained at a mean of 29.6 months; three patients had died (two cancers, one myocardial infarction); 10 had no or minimal sequelae; one had post-phlebitic limb. Conclusion: Mechanical thrombectomy is a potential therapeutic option in patients presenting with proximal DVT.