The Pig Kidney as an Endourologic Model: Anatomic Contribution

Abstract

We present detailed anatomic findings on collecting system anatomy and renal morphometry in the pig and compare these findings with previous findings in humans. We studied three-dimensional polyester resin corrosion endocasts of the pelviocaliceal system obtained from 100 kidneys (50 pigs). Eighty kidneys were evaluated morphometrically, considering length, cranial pole width, caudal pole width, thickness, and weight. The pig collecting system was classified into two major groups (A and B). Group A (40%) was composed of kidneys in which the mid-zone is drained by calices dependent on the cranial or the caudal caliceal group or both. Group B (60%) kidneys have the mid-zone drained by calices independent of the polar groups. Group B includes two subtypes (B-I and B-II). The pig collecting system showed only angles smaller than 90 degrees between the caudal (lower) infundibulum and the renal pelvis. Renal morphometric measurements revealed the following means: length 11.8 cm, cranial pole width 5.64 cm, caudal pole width 5.35 cm, thickness 2.76 cm, and weight 98 g. As in human kidneys, one may group the pig collecting system into two groups. Nevertheless, in pigs, we did not find a subdivision of Group A. The incidence of collecting systems in Groups A and B and the subtypes of Group B in pigs are different from those in humans. Also different from humans, in pigs, we found only angles smaller than 90 degrees between the caudal (lower) infundibulum and the renal pelvis. Except for the length, the means of the other morphometric measurements of the pig kidney are smaller than those of humans. From an anatomic standpoint, despite the differences pointed out, we conclude that the pig kidney is a good animal model for endourologic research and training.

Morphological Characterization of the Renal Arteries in the Pig: Comparative Analysis with the Human

“…(Evan et al). The external dimensions of the kidneys of our work are consistent with those reported in prior studies (Schwarze & Roldán, 1970;Getty, 1995;Sampaio et al, 1998); the mean dimensions reported in humans are: Length 11.1 cm, cranial pole 6.44 cm, caudal pole 5.49 cm, and thickness 3.29 cm, thus being slightly larger than those reported in pigs (Sampaio & Lacerda, 1989;Sampaio & Aragao, 1992). …”

The Dog Kidney as Experimental Model in Endourology: Anatomic Contribution

“…In these cases, the width of the cranial pole was greater than the width of the caudal pole, and this difference was statistically significant. 4,7 In the present work, there was no statistically significant difference between cranial pole and caudal pole widths in dogs. The relationship between the renal width and the length was about 6:11 (5.99:10.80), similar to that of the human kidney (5.97:11.09).…”

“…4,6 Briefly, yellow polyester resin (approximate volume 3 mL) mixed with 3% methyl ethyl peroxide (catalyst for the resin) was injected into the ureter to fill the kidney collecting system. Perirenal fat was removed and the kidneys were morphometrically evaluated.…”

“…[1][2][3] In recent years, the pig kidney has been considered the best urologic experimental model because of its anatomic resemblance to the human kidney. 4,5 For many institutions, however, swine procurement and their maintenance as well as management in the laboratory setting are difficult, so that other animals have been used in research on the urinary system.…”

Morphometry and Vascularization of the Rabbit Kidneys (Oryctolagus cuniculus)

“…Pigs are more often used because their kidney most closely resembles the structural features of the human kidney (Sampaio et al, 1998). On the other hand, rabbits have been used as urologic models in many studies, such as radiofrequency ablation (RFA) (Miao et al, 2001) magnetic resonance imaging (Hynynen et al, 1996), histotripsy (Roberts et al, 2006), lithotripsy (Fernández et al, 2009) and partial nephrectomy (Tyritzis et al, 2007).…”