pyelovenous backflow
noun
py·elo·ve·nous back·flow
| \ -ˈvē-nəs-ˈbak-ˌflō
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Medical Definition of pyelovenous backflow
: drainage of fluid from the renal pelvis of a kidney into the renal venous system under certain conditions (as in retrograde pyelography) in which abnormal amounts of pressure occur in a direction opposite to normal
— called also pyelovenous reflux