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Objective: The purpose of this study was to evaluate the radiation exposure of vascular surgeons' eye lens and fingers during complex endovascular procedures in modern hybrid operating rooms., Methods: Prospective, nonrandomized multicenter study design. One hundred seventy-one consecutive patients (138 male; median age, 72.5 years [interquartile range, 65-77 years]) underwent an endovascular procedure in a hybrid operating room between March 2012 and July 2013 in two vascular centers. The dose-area product (DAP), fluoroscopy time, operating time, and amount of contrast dye were registered prospectively. For radiation dose recordings, single-use dosimeters were attached at eye level and to the ring finger of the hand next to the radiation field of the operator for each endovascular procedure. Dose recordings were evaluated by an independent institution. Before the study, precursory investigations were obtained to simulate the radiation dose to eye lens and fingers with an Alderson phantome (RSD, Long Beach, Calif)., Results: Interventions were classified into six treatment categories: endovascular repair of infrarenal abdominal aneurysm (n = 65), thoracic endovascular aortic repair (n = 32), branched endovascular aortic repair for thoracoabdominal aneurysms (n = 17), fenestrated endovascular aortic repair for complex abdominal aortic aneurysm, (n = 25), iliac branched device (n = 8), and peripheral interventions (n = 24). There was a significant correlation in DAP between both lens (P < .01; r = 0.55) and finger (P < .01; r = 0.56) doses. The estimated fluoroscopy time to reach a radiation threshold of 20 mSv/y was 1404.10 minutes (90% confidence limit, 1160, 1650 minutes). According to correlation of the lens dose with the DAP an estimated cumulative DAP of 932,000 mGy/m(2) (90% confidence limit, 822,000, 1,039,000) would be critical for a threshold of 20 mSv/y for the eyes., Conclusions: Radiation protection is a serious issue for vascular surgeons because most complex endovascular procedures are delivering measurable radiation to the eyes. With the correlation of the DAP obtained in standard endovascular procedures a critical threshold of 20 mSv/y to the eyes can be predicted and thus an estimate of a potential harmful exposure to the eyes can be obtained., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Introduction: (90)Y-Zevalin labeling may cause severe finger radiation exposure, especially in high-dose protocols (HD-Zevalin), where up to 7.4 GBq could be injected. In this work, we optimized the labeling of HD-Zevalin with special regard to simplicity, speed, safety and radiation protection., Methods: Factors influencing labeling outcome (activity, specific activity, time, final volume, stability) were studied separately. The critical steps of a standard radiolabeling procedure were optimized to reduce finger exposure, developing an alternative labeling procedure and including a different (90)Y supplier. Finger doses were monitored by thermoluminescent dosimeters at each fingertip under anti-X gloves, considering both absolute values and values after normalization to 1.48 GBq., Results: Labeling of (90)Y-Zevalin was safe and reproducible up to 7.4 GBq with a simple and single-step procedure offering good stability for several hours. Radiolabeling specific activity was found critical, being kept at 740 MBq mg(-1). Radiochemical purity values >or=98% were routinely achieved. The alternative procedure allowed a sensible reduction of finger dose, due to both the different (90)Y vial and the handling. Finger exposure was reduced from 6.6+/-4.3 to 3.1+/-0.8 mSv/1.48 GBq in the case of the original (90)Y vial and from 1.5+/-0.9 to 0.3+/-0.1 mSv/1.48 GBq using a shielded (90)Y vial., Conclusions: HD-Zevalin can be prepared in a safe and reproducible way, giving high radiochemical purity values, good stability and low finger exposure. This study may improve the safety of nuclear medicine professionals involved in the preparation of Zevalin., (Copyright 2010 Elsevier Inc. All rights reserved.)

Objective: Most non-invasive brain-computer interfaces (BCIs) classify EEG signals. Here, we measured brain activity with magnetoencephalography (MEG) with an aim to characterize and classify single MEG trials during finger movements. We also examined whether averaging consecutive trials, or averaging signals from neighboring sensors, would improve classification accuracy., Methods: MEG was recorded in five subjects during lifting the left, right or both index fingers. Trials were classified using features, defined by an expert, from averaged spectra and time-frequency representations., Results: Classification accuracy of left vs. right finger movements was 80-94%. In the three-category classification (left, right, both), accuracy was 57-67%. Averaging three consecutive trials improved classification significantly in three subjects. Instead, spatial averaging across neighboring sensors decreased accuracy., Conclusions: The use of averaged signals to find appropriate features for single-trial classification proved useful for the two-class classification. The classification accuracy was comparable to that in previous EEG studies., Significance: MEG provides another useful method to measure brain signals to be used in BCIs. Good performance was obtained when the classified signals were generated by two distinct sources in the left and right hemisphere. The present findings should be extended to multi-task cases involving additional brain areas.