establishment of the zertruemmern konkrementen.

摘要

The equipment has a shock-wave generator (17) and an X-ray machine with one or more image memories (21). A comparator (24) compares the stored image with the next recorded image and triggers the shock-wave generator when a given requirement is satisfied. Pref. a selector circuit (23) ensures that the comparison is only performed in a zone of particular interest. The triggering requirement may be a set number of differences in the images compared or a set number of odentical points. The comparison is analysed by an evaluation circuit (25) connected to a threshold circuit (26). Pref. the output signal from a detector (22) which senses min. movement of the concretion is used to control the storage operation.