Functional shoulder radiography with use of a dynamic flat panel detector

[Paradigm Shift in Respiratory Diagnosis: Current Status and Future Prospects of Dynamic Chest Radiography]

Dynamic chest radiography (DCR) is a flat-panel detector (FPD) -based functional X-ray imaging, which is performed as an additional examination in chest radiography. The large field of view of FPDs permits real-time observation of motion/kinetic findings on the entire lungs, right and left diaphragm, ribs, and chest wall; heart wall motions; respiratory changes in lung density; and diameter of the intrathoracic trachea. Since the dynamic FPDs had been developed in the early 2000s, we focused on the potential of dynamic FPDs for functional X-ray imaging and have launched a research project for the development of an imaging protocol and digital image-processing techniques for the DCR. The quantitative analysis of motion/kinetic findings is helpful for a better understanding of pulmonary function, because the interpretation of dynamic chest radiographs is challenging and time-consuming for radiologists, pulmonologists, and surgeons. Recent clinical studies have demonstrated the usefulness of DCR combined with the digital image processing techniques for the evaluation of pulmonary function and circulation. Especially, there is a major concern in color-mapping images based on dynamic changes in radiographic lung density, where pulmonary impairments can be detected as color defects, even without the use of contrast media or radioactive medicine. Dynamic chest radiography is now commercially available for the use in general X-ray room and therefore can be deployed as a simple and rapid means of functional imaging in both routine and emergency medicine. This review article describes the current status and future prospects of DCR, which might bring a paradigm shift in respiratory diagnosis.

Reliability of scapular kinematics estimated with three-dimensional motion analysis during shoulder elevation and flexion

BACKGROUND

Knowing the reliability of three-dimensional motion analysis to evaluate scapular kinematics during upper limb movements is essential to plan further research dedicated to understanding scapulothoracic joint movements relative to the global shoulder motion.

RESEARCH QUESTION

The aim of this study was to assess the intra-subject as well as intra- and interrater reliability of scapulothoracic joint angles during shoulder elevation in scapular plane and shoulder flexion.

METHODS

Twenty healthy participants (26.6 ± 3.5 years) were asked to perform maximum shoulder elevation in scapular plane as well as shoulder flexion. Reliability was assessed using the intraclass correlation coefficient (ICC) and its 95% confidence interval of scapular kinematics (rotation, tilting, pro-retraction) at each degree of global motion (shoulder elevation or shoulder flexion) between 0° to 150°.

RESULTS

ICCs above 0.60 were accepted as good indicators for reliability. Intra-subject reliability was found to be very high (>0.9 for most part) for all scapulothoracic joint angles during both movements. Intra- and interrater reliability also showed good reliability being above 0.60 for the most part (except scapula tilting during shoulder elevation). Scapular kinematics showed low reliability during the respective first 10° and 20° of shoulder elevation and shoulder flexion. Furthermore, decreasing reliability was found above 120° of shoulder elevation or flexion.

SIGNIFICANCE

This study generally showed good to high levels of reliability in the range of interest (20-120°) in evaluating scapula kinematics in healthy adults during shoulder elevation and flexion; these results are important for future research providing a better understanding of scapular kinematics.

Functional dynamic radiography with computer analysis-for physiological chest imaging and kinematic joint imaging

We developed a functional digital radiography system that provides physiological and functional information of the chest and/or joints using an X-ray flat-panel detector (FPD) system. During chest examination, sequential chest radiographs are taken from inspiration to expiration in order to analyze diaphragmatic movements. Pixel value changes in localized areas of the lung are then assessed to analyze ventilation and circulation. For limb joints, such as the wrist, shoulder, and knee, sequential radiographs during flexion and extension or rotational movement are considered, and movement angles are analyzed. These imaging techniques and quantitative analyses are promising in screening examinations because they provide physiological and functional information. The entrance surface dose for the detector is approximately 1.9 mGy for chest examination, which is comparable to the dose limit recommended by the International Atomic Energy Agency. Recent related studies are reviewed in this paper.