Ultrafast cadmium-zinc-telluride-based renal single-photon emission computed tomography: clinical validation.

BACKGROUND: One of the main limitations of 99mtechnetium-dimercaptosuccinic acid (DMSA) scan is the long acquisition time. OBJECTIVE: To evaluate the feasibility of short DMSA scan acquisition times using a cadmium-zinc-telluride-based single-photon emission computed tomography (SPECT) system in children. MATERIALS AND METHODS: The data of 27 children (median age: 4 years; 16 girls) who underwent DMSA SPECT were retrospectively analyzed. Both planar and SPECT DMSA were performed. SPECT images were analyzed using coronal-simulated planar two-dimensional images. A reduction in SPECT acquisition time was simulated to provide 4 series (SPECT-15 min, SPECT-10 min, SPECT-5 min and SPECT-2.5 min). A direct comparison of the planar and SPECT series was performed, including semi-quantification reproducibility, image quality (mean quality score on a scale of 0 to 2) and inter- and intra-observer reproducibility of the scintigraphic patterns. RESULTS: The overall image quality score (± standard deviation) was 1.3 (± 0.6) for the planar data set, 1.6 (± 0.5) for the SPECT-15 min data set, 1.4 (± 0.5) for the SPECT-10 min data set, 1.0 (± 0.5) for the SPECT-5 min data set and 0.6 (± 0.6) for the SPECT-2.5 min data set. Median Kappa coefficients for inter-observer agreement between planar and SPECT images were greater than 0.83 for all series and all readers except one reader for the SPECT-2.5 min series (median Kappa coefficient = 0.77). CONCLUSION: Shortening SPECT acquisitions to 5 min is feasible with minimal impact on images in terms of quality and reproducibility.

Cognitive and body manifestations of driving anxiety according to different onsets.

BACKGROUND: Driving anxiety can have deleterious effects not only on driving behavior, but also on life quality. The interaction between motor vehicle collision (MVC) experiences and driving anxiety has been studied from different standpoints. However, the comparison with other events triggering it has been scarcely considered. Objectives: To analyze the body manifestations and the driving cognitions related to the accident, social and panic concerns in people suffering from different levels of driving anxiety. Method: A total of 260 participants suffering from driving anxiety were included in a survey, including Driving Cognition Questionnaire and Body Sensation Questionnaire. Results: Panic attacks and criticisms are the most relevant onsets of driving anxiety, more than MVC. Only 11.4% of MVC victims considered it as the onset. People with MVC history showed lower scores in social concerns than people without MVC experience and neither the responsibility of the MVC nor the role (driver/passenger) seemed to have an impact on the anxiety level. Conclusions: Although the most relevant body sensations, heart palpitations and sweating, were the same in people with panic attack experiences and MVC victims, a discrimination of the emotions behind the concept of "driving anxiety" is desirable to clarify the psychological effects of different onsets.

Impact of totally and partially predictive alert in distracted and undistracted subjects: An event related potential study.

Rear-end collisions represent about 30% of all car crashes and generate a significant economic cost for society. Driver inattention has been identified as the most important contributing factor in rear-end collisions. One possible countermeasure is the use of systems that warn drivers of potential collisions. Nevertheless, because of technical constraints, the conception of perfect warning systems is difficult to achieve and technical literature shows that these kinds of systems can be prone to false alerts or misses. The main objective of this study is to assess the impact of such a warning system on the processing of a relevant driving visual cue while taking into account the reliability of the system and the attentional state of the participants. For this, we designed a laboratory experiment during which we recorded behavioral data and brain activity (event related potential, ERP) following the detection of a visual target. Three warning conditions were designed: (1) no alert was presented before the visual target; (2) an auditory alert was presented before each target; (3) an alert was presented before the target in 70% of the trials (15% only had the alert without the target, and 15% only had the target without the alert). In addition, participants had to perform this visual detection task either alone (simple task) or with a concurrent problem-solving task (dual task). Behavioral and electrophysiological data contribute to revealing (1) that there is a behavioral gain induced by the alert and (2) that this gain is at least linked with a time-saving aspect at both the sensory and cognitive stages of neural information processing. Nevertheless, this impact depends on the attentional states of the participant and on the reliability of the alert.