STUDIES OF THE OPERATIVE PROCEDURE FOR NEPHROLITHOTOMY

Part 1. Vertical Interrupted Parenchymal Suture

Abstract

Although vertical interrupted parenchymal suture for nephrotomy is thought to be a well defined technical procedure, damage to the postoperative function of the kidney can not be disregarded. Experimentally I have studied the effect of nephrolithotomy on renal function with special reference to microcirculation using microangiography.
Fourteen kidneys in 14 dogs were subjected to renal bivalve incisions made from the upper to the lower pole and deepened sufficiently to allow access to the pelvis. This incision was made in the convex border of the kidney. The kidney was reconstituted using a continuous pelvic suture and also vertical interrupted parenchymal sutures. The contralateral kidney was not treated. All operated kidneys had 30min of ischemia. The results were summarized as follows:
1) The influences of the nephrotomy on the vascular system were slight.
2) In the group 2 weeks after operation, a large wedge avascular area near the incision could be seen. In this area, histopathologically, necrotic tissue was recognized. AV-fistula were seen in some cases.
3) In the group 2 months after operation, the large wedge avascular area disappeared. But the renal cortex became thinner.
4) From the point of view of the contact microangiogram, in the 2 weeks group, the minor vasculature was dilatated, tortuous and deviated in the area of parenchymal sutures. And in the 2 months group, the number of glomeruli decreased in the same area.
5) In the 500μ section of the contact microangiographic specimens, the individual glomerular area (gA), the number of glomeruli (No. Gl.) and total vascular area (TVA) which is the sum of the glomerular area (GA) and the vascular area (VA) were measured with a πMC Particle Measurement Computer System. GA (No. Gl×average individual glomerular area) and VA (TVA-GA) were calculated. In the area of parenchymal sutures, there was a decrease of TVA, especially GA in the 2 weeks group, and in the 2 months group, there was a marked decrease of GA compared with the control group. The latter was due to a marked decrease of the number of glomeruli.
Thus, vertical interrupted parenchymal sutures decreased the number of functional glomeruli and I concluded that this was not the ideal operative procedure following nephrotomy.