Fraley syndrome

A condition where the superior infundibulum of the upper calyx is obstructed by the crossing upper segment renal artery branch, causing distension and dilatation of the calyx and presenting clinically as haematuria and nephralgia. The condition was first described by urologist Elwin E. Fraley in 1966 and can be treated surgically, which might be necessary in symptomatic disease. Another possible cause for hydronephrosis is megacalicosis, for which surgery is considered inappropriate.