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Objective: Ferromagnetic material in microchips, used for animal identification, causes local signal increase, signal void or distortion (susceptibility artifact) on MR images. To measure the impact of microchip geometry on the artifact's size, an MRI phantom study was performed., Material and Methods: Microchips of the labels Datamars®, Euro-I.D.® and Planet-ID® (n  =  15) were placed consecutively in a phantom and examined with respect to the ASTM Standard Test Method F2119-07 using spin echo (TR 500 ms, TE 20 ms), gradient echo (TR 300 ms, TE 15 ms, flip angel 30°) and otherwise constant imaging parameters (slice thickness 3 mm, field of view 250 x 250 mm, acquisition matrix 256 x 256 pixel, bandwidth 32 kHz) at 1.5 Tesla. Image acquisition was undertaken with a microchip positioned in the x- and z-direction and in each case with a phase-encoding direction in the y- and z-direction. The artifact size was determined with a) a measurement according to the test method F2119-07 using a homogeneous point operation, b) signal intensity measurement according to Matsuura et al. and c) pixel counts in the artifact according to Port and Pomper., Results: There was a significant difference in artifact size between the three microchips tested (Wilcoxon p = 0.032). A two- to three-fold increase in microchip volume generated an up to 76% larger artifact, depending on the sequence type, phase-encoding direction and chip position to B0., Conclusion and Clinical Relevance: The smaller the microchip geometry, the less is the susceptibility artifact. Spin echoes (SE) generated smaller artifacts than gradient echoes (GE). In relation to the spatial measurement of the artifact, the switch in phase-encoding direction had less influence on the artifact size in GE- than in SE-sequences. However, the artifact shape and direction of SE-sequences can be changed by altering the phase. The artifact size, caused by the microchip, plays a major clinical role in the evaluation of MRI from the head, shoulder and neck regions.

The fate of multiple trauma patients is witnessed by a considerable number of relatives. Although numerous studies report that the patient's course and treatment success are dependent on the family's confidence as well as its clarification over the clinical situation, scientifically based guidelines for contact with relatives in the context of acute care following severe traumatic injuries do not yet exist. The current guidelines of the European Resuscitation Council recommend the concept of "on scene" presence for the integration of the relatives into acute care in situations of circulatory and heart failure, thus recommending the presence of relatives during acute medical care. This article discusses this concept and argues for a possible assignment of management of trauma care for severe and gravely injured patients.

Elbow joints of a random sample of 59 cats were investigated by means of X-rays and dissection as well as histologically and by making cuts through synthetic resin-embedded joints. Bone-dense shadow craniolateral to the elbow joint was observed in X-ray images of 23 limbs (about 20%). Furthermore 8 of these 23 elbow joints (about 7%) showed signs of arthrotic alteration. Histologic examination revealed one or more centers of metaplasia of varying status of development of the annular ligament of the radius. Alterations varied from chondroid metaplasia to mineralisation and ossification. They turned out to be located in the area where the annular ligament of the radius crosses the tendon of origin of the supinator muscle and are considered to be a reaction of tough connective tissue to mechanical stress. Compressive forces seem to be less responsible than tensile stress. As soon as bone-dense shadow is observed in X-ray images, alterations have grown so far as the annular ligament of the radius as well as the tendon of origin of the supinator muscle are affected.