The Effect of Direct Observation of Procedural Skills Assessment Method on Clinical Performance of Radiology Students

Background and Objectives Assessment is one of the most important factors involved in effective medical education. Direct observation of procedural skills (DOPS) assessment method requires direct observation of learners during the performance of clinical procedures on patients and providing appropriate feedback to learners. This research was carried out to evaluate the effect of DOPS assessment method on the clinical performance of radiology students at Kermanshah University of Medical Sciences. Methods This study was performed on 30 undergraduate radiology students at the teaching hospitals of Kermanshah University of Medical Sciences in 2017. The participants were randomly divided into intervention and control groups. Data were collected via observation and completion of a researcher-made checklist before and after the apprenticeship course. The data were analyzed using independent t-test and paired t-test. Results There was no significant difference between the groups regarding the demographic variables. There was no significant difference between the intervention and control groups in the mean score of students’ clinical skills in pretest (P = 0.911), but the mean score in the intervention group with DOPS assessment method significantly increased in comparison with that of the control group at the end of the apprenticeship course (P = 0.001). Conclusions The DOPS clinical assessment method significantly improves the practical and clinical skills and self-confidence of radiology students at clinical education centers and can be used as a more effective method than conventional clinical assessment methods

Effect of Phase-Encoding Reduction on Geometric Distortion and BOLD Signal Changes in fMRI

Introduction Echo-planar imaging (EPI) is a group of fast data acquisition methods commonly used in fMRI studies. It acquires multiple image lines in k-space after a single excitation, which leads to a very short scan time. A well-known problem with EPI is that it is more sensitive to distortions due to the used encoding scheme. Source of distortion is inhomogeneity in the static B0 field that causes more geometric distortion in phase encoding direction. This inhomogeneity is induced mainly by the magnetic susceptibility differences between various structures within the object placed inside the scanner, often at air-tissue or bone-tissue interfaces. Methods of reducing EPI distortion are mainly based on decreasing steps of the phase encoding. Reducing steps of phase encoding can be applied by reducing field of view, slice thickness, and/or the use of parallel acquisition technique. Materials and Methods We obtained three data acquisitions with different FOVs including: conventional low resolution, conventional high resolution, and zoomed high resolution EPIs. Moreover we used SENSE technique for phase encoding reduction. All experiments were carried out on three Tesla scanners (Siemens, TIM, and Germany) equipped with 12 channel head coil. Ten subjects participated in the experiments. Results The data were processed by FSL software and were evaluated by ANOVA. Distortion was assessed by obtaining low displacement voxels map, and calculated from a field map image. Conclusion We showed that image distortion can be reduced by decreasing slice thickness and phase encoding steps. Distortion reduction in zoomed technique resulted the lowest level, but at the cost of signal-to-noise loss. Moreover, the SENSE technique was shown to decrease the amount of image distortion, efficiently