Objective Indications for the treatment of cerebral aneurysms with flow diversion stents are expanding. The current aneurysm occlusion rate at six months ranges between 60 and 80%. Predictability of complete vs. partial aneurysm occlusion is poorly defined. Here, we evaluate the angiographic contrast time-density as a predictor of aneurysm occlusion rate at six months’ post-flow diversion stents. Methods Patients with unruptured cerebral aneurysms proximal to the internal carotid artery terminus treated with single flow diversion stents were included. 2D parametric parenchymal blood flow software (Siemens-Healthineers, Forchheim, Germany) was used to calculate contrast time-density within the aneurysm and in the proximal adjacent internal carotid artery. The area under the curve ratio between the two regions of interests was assessed at baseline and after flow diversion stents deployment. The area under the curve ratio between completely vs. partially occluded aneurysms at six months’ follow-up was compared. Results Thirty patients with 31 aneurysms were included. Mean aneurysm diameter was 8 mm (range 2–28 mm). Complete occlusion was obtained in 19 aneurysms. Younger patients ( P = 0.006) and smaller aneurysms ( P = 0.046) presented higher chance of complete obliteration. Incomplete occlusion of the aneurysm was more likely if the area under the curve contrast time-density ratio showed absolute ( P = 0.001) and relative percentage ( P = 0.001) decrease after flow diversion stents deployment. Area under ROC curve was 0.85. Conclusion Negative change in the area under the curve ratio indicates less contrast stagnation in the aneurysm and lower chance of occlusion. These data provide a real-time analysis after aneurysm treatment. If validated in larger datasets, this can prompt input to the surgeon to place a second flow diversion stents.

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Tailings storage facilities (TSFs) are an essential infrastructure of mineral processing, but they represent a significant physical, chemical and biological hazard and must, therefore, be strictly and responsibly sited, managed and closed. Tailings can, for example, be dispersed by many processes (such as sinkholes, earthquakes, intense rainfall and flood events, and wind), substandard design and construction, and seepage. The stability and behaviour of TSFs needs to be continuously monitored and one highly effective way of doing this is through satellite Earth observation (EO). The EO industry is witnessing a technological revolution. Large and long-lifespan satellite sensors that have been the staple of national space agencies and commercial satellite manufacturers are now being complemented by constellations of low-cost, short-lifespan 'cube sats' by companies with the ambition to image the whole earth daily. Satellites with synthetic aperture radar (SAR) sensors are also collecting high volumes of data, with the added benefit of being able to do so day or night and in different weather conditions. The range of data options and capabilities these provide open opportunities for novel data analysis techniques for TSFs. One of these is satellite InSAR (interferometric SAR; a technique used to map millimetric-precision changes in ground height over time), which is already used by mining companies to reduce risk in and of their operations. From monitoring the stability of TSFs, through to assessments of impacts of natural hazards, InSAR allows rapid and accurate targeting of high-risk areas and structures to identify those that require subsequent investigation through ground-based methods. To demonstrate the application of EO data and InSAR in identifying pre-and post-failure mine activities and TSF deformation, the authors will present a case study across Cadia mine, New South Wales, Australia, which had a localised TSF failure on 9 March 2018. The InSAR results presented show that low-magnitude subsidence signals were observed across the TSF dam during the year preceding the collapse. In January 2018 a notable change in behaviour was observed, with a concentrated area of subsidence focused on the region which initially failed on 9 March 2018. Furthermore, post-collapse InSAR measurements show an increased rate of subsidence for regions either side of the failure zone. Review of medium-and high-resolution satellite images show that the failure was phased, with an initial failure and then a subsequent failure at least two days after 9 March 2018. It also highlights what might be construction activity associated with a dam raise prior to failure.

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Staghorn calculi account for about 4% of presenting renal stones in developed countries, are source of recurrent urinary tract infection, and may be eventually treated by surgical stone removal. A 55-year-old female with a history of staghorn renal calculi and recurrent urinary tract infections presented with a left flank and lower abdominal pain following recent left robotic partial nephrectomy and nephrolithotomy. Contrast-enhanced computed tomography (CT) of the abdomen demonstrated a large left-sided retroperitoneal fluid collection with a few dropped renal stones in the dependent portion of the collection. The patient treated with early percutaneous drainage of the collection and antibiotic treatment and responded well clinically. The clinical and imaging presentation of a rare case of retroperitoneal abscess formation caused by dropped renal stones is described in this study. Imaging, particularly ultrasound and CT, plays a key role in detecting the dropped renal stones and can help with differential diagnosis and treatment plans.