This study of carefully and prospectively collected data shows the prevalence of parastomal herniation to be 33%. This rate was higher with larger aperture size and increased age in multivariate analysis.

Background and AimHigh tidal volume (VT) ventilation during resuscitation of preterm lambs results in brain injury evident histologically within hours after birth. We aimed to investigate whether magnetic resonance spectroscopy (MRS) and/or diffusion tensor imaging (DTI) can be used for early in vivo detection of ventilation-induced brain injury in preterm lambs.MethodsNewborn lambs (0.85 gestation) were stabilized with a “protective ventilation” strategy (PROT, n = 7: prophylactic Curosurf, sustained inflation, VT 7 mL/kg, positive end expiratory pressure (PEEP) 5 cmH2O) or an initial 15 minutes of “injurious ventilation” (INJ, n = 10: VT 12 mL/kg, no PEEP, late Curosurf) followed by PROT ventilation for the remainder of the experiment. At 1 hour, lambs underwent structural magnetic resonance imaging (Siemens, 3 Tesla). For measures of mean/axial/radial diffusivity (MD, AD, RD) and fractional anisotropy (FA), 30 direction DTI was performed. Regions of interests encompassed the thalamus, internal capsule, periventricular white matter and the cerebellar vermis. MRS was performed using a localized single-voxel (15×15×20 mm3, echo time 270 ms) encompassing suptratentorial deep nuclear grey matter and central white matter. Peak-area ratios for lactate (Lac) relative to N-acetylaspartate (NAA), choline (Cho) and creatine (Cr) were calculated. Groups were compared using 2-way RM-ANOVA, Mann-Whitney U-test and Spearman's correlations.ResultsNo cerebral injury was seen on structural MR images. Lambs in the INJ group had higher mean FA and lower mean RD in the thalamus compared to PROT lambs, but not in the other regions of interest. Peak-area lactate ratios >1.0 was only seen in INJ lambs. A trend of higher mean peak-area ratios for Lac/Cr and Lac/Cho was seen, which correlated with lower pH in both groups.ConclusionAcute changes in brain diffusion measures and metabolite peak-area ratios were observed after injurious ventilation. Early MRS/DTI is able to detect the initiation of ventilation-induced brain injury.

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Background “Functional” [18F]-fluorodeoxyglucose positron emission tomography (FDG-fPET) is a new approach for measuring glucose uptake in the human brain. The goal of FDG-fPET is to maintain a constant plasma supply of radioactive FDG in order to track, with high temporal resolution, the dynamic uptake of glucose during neuronal activity that occurs in response to a task or at rest. FDG-fPET has most often been applied in simultaneous BOLD-fMRI/FDG-fPET (blood oxygenation level–dependent functional MRI fluorodeoxyglucose functional positron emission tomography) imaging. BOLD-fMRI/FDG-fPET provides the capability to image the 2 primary sources of energetic dynamics in the brain, the cerebrovascular haemodynamic response and cerebral glucose uptake. Findings In this Data Note, we describe an open access dataset, Monash DaCRA fPET-fMRI, which contrasts 3 radiotracer administration protocols for FDG-fPET: bolus, constant infusion, and hybrid bolus/infusion. Participants (n = 5 in each group) were randomly assigned to each radiotracer administration protocol and underwent simultaneous BOLD-fMRI/FDG-fPET scanning while viewing a flickering checkerboard. The bolus group received the full FDG dose in a standard bolus administration, the infusion group received the full FDG dose as a slow infusion over the duration of the scan, and the bolus-infusion group received 50% of the FDG dose as bolus and 50% as constant infusion. We validate the dataset by contrasting plasma radioactivity, grey matter mean uptake, and task-related activity in the visual cortex. Conclusions The Monash DaCRA fPET-fMRI dataset provides significant reuse value for researchers interested in the comparison of signal dynamics in fPET, and its relationship with fMRI task-evoked activity.

In a consecutive series of 201 emergency operations in patients with bleeding duodenal ulcer the size of the ulcer was the only factor that showed a significant correlation with the procedure chosen. Vagotomy, pyloroplasty and underrunning of the bleeding point was performed in 101 cases with ten deaths (10 per cent), partial (Billroth II) gastrectomy in 81 cases with ten deaths (12 per cent), and vagotomy and antrectomy in 16 cases with one death (6 per cent). A patient was more likely to be treated by partial gastrectomy if a giant ulcer with an internal diameter of greater than or equal to 2 cm was found. The results suggest that while vagotomy and pyloroplasty, combined with a direct attack on the bleeding point or excision of an anterior ulcer is an acceptable standard emergency operation for bleeding duodenal ulcer, gastric resection proved to be a satisfactory alternative procedure and should be considered in the technically difficult case with a very large ulcer. A giant ulcer was present in 37 per cent of cases coming to surgery.

Understanding how the living human brain functions requires sophisticated in vivo neuroimaging technologies to characterise the complexity of neuroanatomy, neural function, and brain metabolism. Fluorodeoxyglucose positron emission tomography (FDG-PET) studies of human brain function have historically been limited in their capacity to measure dynamic neural activity. Simultaneous [18 F]-FDG-PET and functional magnetic resonance imaging (fMRI) with FDG infusion protocols enable examination of dynamic changes in cerebral glucose metabolism simultaneously with dynamic changes in blood oxygenation. The Monash vis-fPET-fMRI dataset is a simultaneously acquired FDG-fPET/BOLD-fMRI dataset acquired from n = 10 healthy adults (18–49 yrs) whilst they viewed a flickering checkerboard task. The dataset contains both raw (unprocessed) images and source data organized according to the BIDS specification. The source data includes PET listmode, normalization, sinogram and physiology data. Here, the technical feasibility of using opensource frameworks to reconstruct the PET listmode data is demonstrated. The dataset has significant re-use value for the development of new processing pipelines, signal optimisation methods, and to formulate new hypotheses concerning the relationship between neuronal glucose uptake and cerebral haemodynamics.

Interpretation: In PLWH on or off ART, the intervention of infusing 64 Cu-3BNC117 and MRI/PET imaging over 48 hours, was unable to detect HIV-1 env expression in vivo. Future studies should investigate alternative radiolabels such as zirconium which have a longer half-life in vivo.

Keywords: Positron emission tomography (PET); Fluorodeoxyglucose (FDG); constant infusion; bolus plus 1 infusion; slow infusion; simultaneous blood oxygenation level dependent functional magnetic resonance 2 imaging fluorodeoxyglucose positron emission tomography (BOLD-fMRI/FDG-PET); functional PET (fPET); 3 dynamic PET 4 5Summary: Radiotracer infusion protocols for positron emission tomography (PET) provide improved temporal 6 resolution over bolus administration. Here, we describe radiotracer administration for two protocols, constant 7 infusion and bolus plus infusion protocol. We compare this to the standard bolus administration protocol. 8Using [18-F] fluorodeoxyglucose PET (FDG-PET) as an example, we show that temporal resolutions of 9 approximately 16sec are achievable using these protocols. 10 11Abstract 1 2Functional Positron Emission Tomography (fPET) provides a method to track molecular dynamics in the human 3 brain. With a radioactively labelled glucose-analogue, [18F]-flurodeoxyglucose (FDG-fPET), it is now possible to 4 index the dynamics of glucose metabolism with temporal resolutions approaching those of functional 5 magnetic resonance imaging (fMRI). This direct measure of glucose uptake has enormous potential for 6 understanding normal and abnormal brain function, and probing the effects of metabolic and 7 neurodegenerative diseases. Further, new advances in hybrid MR-PET hardware makes it possible to capture 8 fluctuations in glucose and blood oxygenation simultaneously using fMRI and FDG-fPET. 9 10The temporal resolution and signal-to-noise of the FDG-fPET images is critically dependent upon the 11 administration of the radioactive tracer. In this work we present two alternative continuous infusion protocols 12and compare them to a traditional bolus approach. We detail a method for acquiring blood samples, time-13 locking PET, MRI and experimental stimulus, and administrating the non-traditional tracer delivery. By 14 applying a visual stimulus, we demonstrate cortical maps of the glucose-response to external stimuli on an 15individual level with a temporal resolution of 16-seconds. 16 17[FIGURE 1 HERE] 43