No abstract

This paper presents three case reports as a basis for discussing the differential diagnosis of retroperitoneal processes and for describing the possibilities and limitations of diagnostic imaging procedures. A definitive differentiation is not possible by CT and MRI alone, but always requires histologic confirmation. Nevertheless, imaging procedures are indispensable for assessing the extent of a lesion and for follow-up. On the basis of the cases presented here and reports in the literature, it can be hypothesized that benign retroperitoneal fibrosis is caused by a chronic inflammatory or autoimmune response of the vessels since the vast majority of cases are associated with pronounced wall abnormalities of the abdominal aorta.

15 patients with suspected cerebral ischaemia were examined using 99mTc-HM-PAO-SPECT to assess cerebral blood flow. Results obtained from SPECT were correlated with CT and Doppler ultrasound findings. A 3D-display algorithm is proposed to enhance the lesion to non-lesion contrast compared to the standard 2D-image interpretation. In all cases contrast was superior on 3D-display to 2D-display (-0.38 versus -0.09). 3D-display of SPECT-data enhances lesion contrast due to postreconstructive data processing and may improve exact interpretation of cerebral blood flow studies.