The July 2003 Case of the Month (COM). A 62-year-old female patient experienced progressive muscular weakness over the last ten years, involving shoulder and pelvic girdle muscles, paraspinal and facial muscles. A biopsy was taken from the left deltoid muscle where hepatitis vaccination had taken place 4 weeks previously. The specimen revealed macrophagic myofasciitis due to the injection of aluminium-bound vaccines. The finding can be reproduced experimentally by injecting vaccines in rats. The pathomechanism is supposed to involve immune stimulation due to long term persistence of the adjuvant. Macrophagic myofasciitis has been suggested to occasionally cause myopathy but is supposed to be unrelated to the underlying myopathy in our patient.

In certain metallurgical applications of SEM, such as the observation of deformation effects, and the recovery and recrystallization processes in bulk specimens, it is of special interest to obtain information about local inhomogeneities of the dislocation densities in a sample. This can be obtained using TEM on thin foils. Previously information on distortion in cold-worked specimens was obtained by measuring the dependence of the deterioration of the resolution of the selected area channelling patterns (SACP) on the degree of deformation. This method, however, is not applicable to highly deformed materials. Direct SEM imaging of the cell structure of the dislocation network has been achieved without resolving single dislocations by using a suitable arrangement of specimen and detector, such that only backscattered electrons (BSE) leaving the surface at a large angle to the normal contribute to the image signals. The signal-to-noise ratio was improved to the degree that it was possible 1) to image the cell structure of the dislocation network and 2) on heating the specimens, to record the growth of recrystallized regions with TV-frame frequency. The imaging of the cell structure gives qualitative information about the degree of crystal deformation and the crystallographic direction of grain boundary motion during recrystallization.