Morphologic study of primary nonreflux megaureters with particular emphasis on the role of ureteral sheath and ureteral dysplasia.
Morphologic study by both light and electron microscopy was done in 21 cases of primary nonreflux megaureter. Cases were divided into 2 groups depending on the level of narrowed segment and extension of ureteral dilatation. In group 1 (18 cases) the narrowed segment was entirely intra-or juxtavesical and ureteral dilatation extended its whole length cranial to it, whereas in group 2 (3 cases) the narrowed segment was extravesical and relatively long, and was often associated with dysmorphism of adjoining kidney and pelvis. Morphology of the 2 groups differed distinctively. In group 1 there was both gross and morphologic evidence suggestive of extensively developed ureteral sheaths. They were implicated as contributing etiologically to the genesis of obstruction at the level of narrowed segment where hitherto documented muscular derangements were also found. In group 2, the genesis of ureteral dilatation appears to rest primarily in the dilated ureteral wall rather than in the normal-appearing narrow segment in that there was morphologic evidence suggestive of dysplasia or arrest in he muscular development of the dilated ureteral wall. Some clinical relevance of the heterogenous morphology of the 2 groups was discussed.
D000328:Adult; D002675:Child, Preschool; D004108:Dilatation, Pathologic; D005260:Female; D006801:Humans; D014513:Ureter / Q000002:abnormalities* / Q000648:ultrastructure*; D014718:Vesico-Ureteral Reflux / Q000150:complications