Is pelvicaliceal anatomy a risk factor for stone formation in patients with solitary upper caliceal stone?

Anatomical study of the renal excretory system in pigs. A review of its characteristics as compared to its human counterpart

“…Since early hydronephrosis expresses itself morphologically with the presence of an ampullar pelvis in humans, it has been postulated that before labelling this feature as an anatomical variant in the clinical scenario, one must rule out an urinary tract obstruction generated by lithiasis, stenosis of the pyeloureteral junction, vesicoureteral reflux, or extrinsic compression caused by light adhesions of the lower polar renal arteries or the gonadal vessels [6,35]. Similarly, it has been postulated that since bifurcated renal pelvises handle smaller urinary volumes, they could become an anatomical substrate for the formation of stones inside these structures [1,18].…”

Do the variations in renal pelvic angles play a role in the formation of renal stone? A computed tomography study

“…1 Underlying etiopathogenesis of renal calculi has not been fully revealed yet, although a wide spectrum of complicated mechanisms including metabolic, epidemiologic and anatomical factors have been suggested to explain the formation of renal stones. [1][2][3][4][5] Both kidneys are equally affected from these risk factors; however, stones are formed only in one kidney in some patients and the recurrence of calculi formation occurs at the same kidney. Beside this, renal stones can also be observed even in some individuals with relatively very low risk.…”

“…Beside this, renal stones can also be observed even in some individuals with relatively very low risk. 2,4,6 This condition does not necessarily depend on metabolic or epidemiologic factors, which in turn may suggest that structural kidney abnormalities and variations may play a role in stone formation process. The incidence of renal stone can increase due to urinary obstruction and stasis seen in some major renal abnormalities such as horseshoe kidney, malrotation, renal ectopia and fusion.…”

“…However, only a few patients who have a unilateral stone suffer from abnormalities. 4,[7][8][9][10] This raises the following question: Can anatomical variations lead to stone formation? Conducted studies in this field have indicated that renal stones more commonly occur due to dependent anatomical configuration of the lower pole calyxes in addition to their other features and it is more frequent in kidneys of people who sleep at the same side position in bed.…”

“…Conducted studies in this field have indicated that renal stones more commonly occur due to dependent anatomical configuration of the lower pole calyxes in addition to their other features and it is more frequent in kidneys of people who sleep at the same side position in bed. 2,4,10,11 Individual habits and minor variations in anatomical structure have a disadvantage and accumulated urine has to flow into the renal pelvis against gravity, which in turn may ameliorate the calculi formation.…”