No abstract

III.

SummaryThis article presents possible applications of ultrasound elastography in musculoskeletal imaging based on the available literature, as well as the possibility of extending indications for the use of elastography in the future. Ultrasound elastography (EUS) is a new method that shows structural changes in tissues following application of physical stress. Elastography techniques have been widely used to assess muscles and tendons in vitro since the early parts of the twentieth century. Only recently with the advent of new technology and creation of highly specialized ultrasound devices, has elastography gained widespread use in numerous applications.The authors performed a search of the Medline/PubMed databases for original research and reviewed publications on the application of ultrasound elastography for musculoskeletal imaging.All publications demonstrate possible uses of ultrasound elastography in examinations of the musculoskeletal system. The most widely studied areas include the muscles, tendons and rheumatic diseases. There are also reports on the employment in vessel imaging.The main limitation of elastography as a technique is above all the variability of applied pressure during imaging, which is operator-dependent. It would therefore be reasonable to provide clear guidelines on the technique applied, as well as clear indications for performing the test. It is important to develop methods for creating artifact-free, closed-loop, compression-decompression cycles.The main advantages include cost-effectiveness, short duration of the study, non-invasive nature of the procedure, as well as a potentially broader clinical availability. There are no clear guidelines with regard to indications as well as examination techniques.Ultrasound elastography is a new and still poorly researched method. We conclude, however, that it can be widely used in the examinations of musculoskeletal system. Therefore, it is necessary to conduct large, multi-center studies to determine the methodology, indications and technique of examination.

SummaryBackgroundInfectious spondylodiscitis is characterized by the involvement of two adjacent vertebrae and the intervening disc. Incidence rate of the disease is estimated at 0.4–2 cases per 100000 per year. Staphylococcus aureus is the most common infectious agent causing pyogenic spondylodiscitis. Non-pyogenic infections of the spine are most frequently caused by Mycobacterium tuberculosis, and fungi. Clinical symptoms are nonspecific. Early diagnosis and appropriate treatment can prevent unfavorable irreversible sequela for the patient.Significant developments in techniques of imaging of pathological tissues raised expectations among the clinicians regarding possibility to distinguish between tuberculous spondylodiscitis and pyogenic spondylodiscitis on MR images. The aim of this study was to identify and differentiate between features of tuberculous and pyogenic spondylodiscitis on MR images.Material/MethodsWe performed retrospective analysis of MR images obtained from 34 patients with confirmed spondylodiscitis (18 with pyogenic spondylodiscitis, and 16 with tuberculous spondylodiscitis). Data acquisition was performed using 1.5 T MRI scanners where images were obtained using similar protocols. T2 TIRM and T1-weighted images with and without contrast enhancement were subject to assessment in coronal, axial and sagittal planes.ResultsCharacteristic features of pyogenic spondylodiscitis include: involvement of the lumbar spine, ill-defined paraspinal abnormal contrast enhancement, diffuse/homogeneous contrast enhancement of vertebral bodies, low-grade destruction of vertebral bodies, hyperintense/homogeneous signal from the vertebral bodies on T2 TIRM images. Prevailing features of tuberculous spondylodiscitis included: involvement of the thoracic spine, involvement of 2 or more adjacent vertebral bodies, severe destruction of the vertebral body, focal/heterogeneous contrast enhancement of vertebral bodies, heterogeneous signal from the vertebral bodies on T2 TIRM images, well-defined paraspinal abnormal contrast enhancement, paraspinal and epidural abscesses, meningeal enhancement at the affected spine level.ConclusionsComparison of MR images of patients diagnosed with pyogenic spondylodiscitis and tuberculous spondylodiscitis allowed identification of individual characteristics for preliminary differentiation between TB and infectious spondylodiscitis and thereby enabling proper treatment.

Airborne infrasound (IS; emitted by e.g., large machinery, wind farms) is ubiquitous in technologized environments. Health hazards are controversially discussed at present. This study investigated long-term effects of IS on brain (regional grey matter volume; rGMV) and behavior in humans. Specifically engineered infrasonic (6 Hz, 80–90 dB) vs. sham devices were installed in participants’ (N = 38) bedrooms and active for 28 nights. Somatic and psychiatric symptoms, sound-sensitivity, sleep quality, cognitive performance, and structural MRI were assessed pre-post. Null findings emerged for all behavioral variables. Exploratory analyses revealed a trend (p = .083) with individuals exposed to IS reporting more physical weakness at post-test (d = 0.38). Voxel-based morphometry (VBM) revealed no rGMV increases, but there were decreases within clusters in the cerebellum VIIIa (bilateral) and left angular gyrus (BA39) in verum. In conclusion, IS does not affect healthy individuals on a global scale. However, future trials should consider more fine-grained specific effects, combining self-report with physiological assessments, particularly directed at bodily sensations and perception. As no brain-behavior-links could be established, the identified grey matter decline cannot be interpreted in terms of potential harmfulness vs. improvement through IS-exposure. Parameters that may best reflect brain changes as established in the present study include motor function, sensory processing/ bodily- and motor-perceptions, working memory, and higher auditory processing (i.e., language-related tasks), which are hence potential target variables for further research.