Veronica Macchi1, Alessandro Crestani2, Andrea Porzionato1, Maria Martina Sfriso1, Aldo Morra3, Marta Rossanese2, Giacomo Novara4, Raffaele De Caro1, Vincenzo Ficarra2,5. 1. Institute of Human Anatomy University of Padova, Padova, Italy. 2. Academic Medical Centre Hospital Santa Maria della Misericordia, Udine, Italy. 3. Section of Radiology, Euganea Medica Center, Padova, Italy. 4. Department of Oncological, Surgical and Gastrointestinal Sciences, Urology Unit, University of Padova, Padova, Italy. 5. Department of Experimental and Clinic Medical Sciences, Urology Unit, University of Udine, Udine, Italy.
Abstract
OBJECTIVES: To validate Graves' classification of the intrarenal arteries and to verify the absence of collateral arterial blood supply between different renal segments, in order to maximize peri-operative and functional outcomes of partial nephrectomy. MATERIALS AND METHODS: The study was performed on 15 normal kidneys sampled from eight unembalmed cadavers. Kidneys with the surrounding perirenal fat tissue were removed en bloc with the abdominal segment of the aorta. The renal artery was injected with acrylic and radiopaque resins, with the specimen suspended in water. CT examination of the injected kidneys was performed to analyse the branches located deeply. After imaging acquisition, the specimens were treated with sodium hydroxide for removal of the parenchyma to obtain vascular casts. RESULTS: Ten casts (66.6%) showed the classic subdivision of the main artery into single posterior and anterior branches. With regard to the distribution of the segmental or second-order arteries, only two casts (13%) showed a pattern similar to that described by Graves, characterized by four segmental (second-order) branches coming from the anterior renal artery (apical, superior, middle and inferior). In the remaining 13 kidneys (87%) a different arterial vascular network was detected. In 10 casts (80%) a single renal segment was vascularized by two or more different branches coming from an artery leading to another segment (multiple vascularization). Multiple vascularization was observed in three (20%) apical segments, five (33%) superior segments, six (40%) middle segments, seven (47%) inferior segments and two (13%) posterior segments. CONCLUSIONS: This study shows that in the human kidneys the arterial vasculature is frequently different from that described by Graves. Moreover, in a significant percentage of cases, a single renal segment receives two or more branches that originate from an artery leading to another segment.
OBJECTIVES: To validate Graves' classification of the intrarenal arteries and to verify the absence of collateral arterial blood supply between different renal segments, in order to maximize peri-operative and functional outcomes of partial nephrectomy. MATERIALS AND METHODS: The study was performed on 15 normal kidneys sampled from eight unembalmed cadavers. Kidneys with the surrounding perirenal fat tissue were removed en bloc with the abdominal segment of the aorta. The renal artery was injected with acrylic and radiopaque resins, with the specimen suspended in water. CT examination of the injected kidneys was performed to analyse the branches located deeply. After imaging acquisition, the specimens were treated with sodium hydroxide for removal of the parenchyma to obtain vascular casts. RESULTS: Ten casts (66.6%) showed the classic subdivision of the main artery into single posterior and anterior branches. With regard to the distribution of the segmental or second-order arteries, only two casts (13%) showed a pattern similar to that described by Graves, characterized by four segmental (second-order) branches coming from the anterior renal artery (apical, superior, middle and inferior). In the remaining 13 kidneys (87%) a different arterial vascular network was detected. In 10 casts (80%) a single renal segment was vascularized by two or more different branches coming from an artery leading to another segment (multiple vascularization). Multiple vascularization was observed in three (20%) apical segments, five (33%) superior segments, six (40%) middle segments, seven (47%) inferior segments and two (13%) posterior segments. CONCLUSIONS: This study shows that in the human kidneys the arterial vasculature is frequently different from that described by Graves. Moreover, in a significant percentage of cases, a single renal segment receives two or more branches that originate from an artery leading to another segment.