[Incidence of pyelectases and their surgical correction]

Among 1611 urological patients 90 (5.4%) displayed pyelectasis. In almost one-third of the cases dilatation was caused by the presence of a calculus In 33 cases plastic surgery mainly of the Anderson-type was applied. 78% of the operations was successful. The incidence of nephrectomy was higher in the group in which complaints were of more than two years standing (10 out of 33) than in the group where treatment was started less than two years after the appearance of complaints (7 out of 41). In 26 cases dilatation was caused by occlusion by a calculus; in one half of these cases, nephrectomy was the only operation which could be performed.