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The aim was to compare a protocol of uterine artery embolization (UAE) consisting in three digital subtraction angiographies (DSAs)-Group A, with a protocol based on a single DSA-Group B.This is a single-center prospective randomized study enrolling 20 women (mean age 41 years, range 22-55 years) with uterine fibroids treated with UAE, from January 2015 to February 2016. All UAEs were performed by two interventional radiologists using the same angiography machine. Protocol of Group A consisted in three DSA runs (non-selective pelvic view and selective uterine views before and after embolization). Protocol of Group B consisted in 1 DSA run: selective UA angiography before embolization. (Fluoroscopic roadmap was used for UA catheterization; fluoroscopy storage was used as control after embolization.) Each patient was randomized to receive Protocol A in one pelvic side and Protocol B on the other.All patients received bilateral UAE. Mean fluoroscopy time for UA catheterization was 11.3 ± 3.7 s. (Protocol A) and 9.93 ± 2.99 s. (Protocol B) (p = 0.19). Fluoroscopy dose for catheterization and embolization was not different between both protocols (p = 0.14). Identification of the UA origin score was similar in both protocols (median error = 0, p = 0.79). Mean dose area product (DAP) was 40859 mGy/cmReducing the number of DSA runs from 3 to 1 during UAE allows at least a 30% reduction on radiation exposure, without compromising technical outcomes.

The precise knowledge of the magnetic field produced by dipole magnets is critical to the operation of a synchrotron. Real-time measurement systems may be required, especially in the case of iron-dominated electromagnets with strong non-linear effects, to acquire the magnetic field and feed it back to various users. This work concerns the design and implementation of a new measurement system of this kind currently being deployed throughout the European Organization for Nuclear Research (CERN) accelerator complex. We first discuss the measurement principle, the general system architecture and the technology employed, focusing in particular on the most critical and specialized components developed, that is, the field marker trigger generator and the magnetic flux integrator. We then present the results of a detailed metrological characterization of the integrator, including the aspects of drift estimation and correction, as well as the absolute gain calibration and frequency response. We finally discuss the latency of the whole acquisition chain and present an outline of future work to improve the capabilities of the system.

An original maxillofacial fracture detection system (MFDS), based on convolutional neural networks and transfer learning, is proposed to detect traumatic fractures in patients. A convolutional neural network pre-trained on non-medical images was re-trained and fine-tuned using computed tomography (CT) scans to produce a model for the classification of future CTs as either “fracture” or “noFracture”. The model was trained on a total of 148 CTs (120 patients labeled with “fracture” and 28 patients labeled with “noFracture”). The validation dataset, used for statistical analysis, was characterized by 30 patients (5 with “noFracture” and 25 with “fracture”). An additional 30 CT scans, comprising 25 “fracture” and 5 “noFracture” images, were used as the test dataset for final testing. Tests were carried out both by considering the single slices and by grouping the slices for patients. A patient was categorized as fractured if two consecutive slices were classified with a fracture probability higher than 0.99. The patients’ results show that the model accuracy in classifying the maxillofacial fractures is 80%. Even if the MFDS model cannot replace the radiologist’s work, it can provide valuable assistive support, reducing the risk of human error, preventing patient harm by minimizing diagnostic delays, and reducing the incongruous burden of hospitalization.

In synchrotrons at the European Organization for Nuclear Research (CERN), magnetic measurement systems known as B-trains measure the magnetic field in the main bending magnets in real-time, and transmit this signal for the control of the synchrotron’s RF accelerating cavities, magnet power converter and beam monitoring systems. This work presents an assessment of the capabilities and performance of the new FIRESTORM (Field In REal-time STreaming from Online Reference Magnets) system as part of the first phase of commissioning. A short summary of the architecture of the measurement system is provided first, followed by the definition of an error model which can be used to characterize random and systematic errors separately. We present a procedure for the metrological calibration and qualification of the B-trains, including an experimental evaluation of the different error sources for the four new systems being commissioned in the Proton Synchrotron Booster (PSB), Low Energy Ion Ring (LEIR), Proton Synchrotron (PS) and the Extra Low ENergy Antiproton (ELENA) ring. In particular, we discuss a method to calibrate systematic gain and offset errors based on the RF cavity frequency offset needed to center the beam on its theoretical orbit.

Integrator drift is a problem strongly felt in different measurement fields, often detrimental even for short-term applications. An analytical method for modelling and feed-forward correcting drift in magnetic flux measurements was developed analytically and tested experimentally. A case study is reported on the proof of principle as a novel kind of quasi-DC field marker of the 5-ppm Nuclear Magnetic Resonance (NMR) transducer Metrolab PT2026, applied to the Extra Low ENergy Antiproton (ELENA) ring and the Proton Synchrotron Booster (PSB) at CERN. In some particle accelerators, such as in ELENA, the resulting feed-forward correction guarantees 1 μ T field stability over 120-s long magnetic cycle on a plateau of 50 mT, reducing by three orders of magnitude the field error caused by the integrator drift with respect to the state of the art.

Objective: Evaluate the efficacy and safety of renal artery embolization (RAE) for iatrogenic renal vascular injuries (IRVI) management at Fondazione Policlinico Universitario "A. Gemelli" IRCCS, in the last 5 years. Methods: Retrospective analysis of all RAE procedures performed from January 2013 to December 2017. Patients-related (age, sex, vascular variants, hemoglobin and serum creatinine), IRVI-related (type and vascular level of IRVI, presence and extension of hematoma), management-related (temporal interval between diagnostic imaging and RAE) and procedure-related (embolic materials, technical success, clinical success and complications) parameters were evaluated. Results: 28 RAE procedures performed on 28 patients (21 males; 7 females) were included. 19/28 patients had pseudoaneurysm, 7/28 active bleeding and 1/28 arteriovenous fistula; 4/28 patients had a combination of 2 IRVI. The extent of perirenal hematoma showed correlation with the cause of IRVI (p = 0.028). Technical success was achieved in all patients whereas clinical success in 25/28 (89.3%), with 3 patients requiring re-treatment. Minor complications were observed during 2/28 (7.1%) endovascular procedures. No major complications occurred. A longer procedural time was observed in patients with lower pre-procedural levels of hemoglobin (p = 0.016). No differences were found in mean serum creatinine (p = 0.23) before and immediately after treatment, while values of creatinine at 1 week from the procedure were significantly lower (p = 0.04). Conclusion: RAE is safe and effective for the management of iatrogenic IRVI showing high technical and clinical success rate and low complication rate. Advances in knowledge: Low pre-procedural hemoglobin levels increase procedural duration time. Glue alone or in combination with other materials is as safe as coils.