Long-term effects of percutaneous nephrolithotomy on renal morphology and arterial vascular resistance as evaluated by color Doppler ultrasonography: preliminary report

The effect of endoscopic renal and ureteral stone surgeries on renal blood flow in children: a prospective trial

AIM

To assess the impact of endoscopic stone surgeries on renal perfusion and blood flow in children.

MATERIALS AND METHODS

Children who underwent percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), ureterorenoscopy (URS), endoscopic combined intrarenal surgery (ECIRS) were included to the study. Renal Doppler ultrasonography (RDUS) was performed one day before the operation, and on the postoperative 1st day and 1st month. Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured, and resistive index (RI) was calculated with the (PSV-EDV)/PSV formula. RDUS parameters were compared before and after surgery and between ipsilateral and contralateral kidneys.

RESULTS

A total of 45 children with a median age was 8 (2-17) years were included (15 (33.3%) girls, 30 (66.7%) boys). PCNL was performed in 13 children (28.9%), RIRS 11 (24.4%), URS 12 (26.7%), and ECIRS 9 (20%). There was no significant difference in renal and segmental PSV, EDV and RI values of operated kidney in the preoperative, postoperative periods. There was no significant difference between RDUS parameters of the ipsilateral and contralateral kidneys in preoperative or postoperative periods. PSV and EDV values were significantly higher in the 1st postoperative month in the group without preoperative DJ stent than in the group with DJ stent (p = 0,031, p = 0,041, respectively). However, RI values were similar. The mean RI were below the threshold value of 0.7 in each period.

CONCLUSION

RDUS parameters didn't show a significant difference in children. Endoscopic surgeries can be safely performed in pediatric stone disease.

Role of Endourological Procedures (PCNL and URS) on Renal Function: a Systematic Review

PURPOSE OF REVIEW

To present the latest evidence related to the impact of ureteroscopy (URS) and percutaneous nephrolithotomy (PCNL) on the renal function.

RECENT FINDINGS

Our review suggests that the overall renal function is not detrimentally affected by endourological interventions (URS, PCNL). This is however influenced by the preoperative renal function, presence of comorbidities such as diabetes and hypertension. For PCNL procedures, tract multiplicity, preoperative UTI, and postoperative bleeding also contribute to a decline in renal function. This review suggests that endourological interventions do not adversely affect renal function and tend to improve it in patients who do not have a poor renal function prior to the procedure. Several factors including poor preoperative renal function, diabetes, hypertension, and multiple percutaneous tracts appear to predispose patients to declining renal function after procedure, and these patients should be counseled for and followed up appropriately.

Prospective evaluation of the alterations in the morphology and vascular resistance of the renal parenchyma with color Doppler ultrasonography after percutaneous nephrolithotomy

PURPOSE

To evaluate the kidneys with color Doppler ultrasonography (CDUS) to determine whether percutaneous nephrolithotomy (PNL) causes renal parenchymal damage.

PATIENTS AND METHODS

In 24 patients who underwent unilateral PNL with single renal pole access, cortical thickness, echogenicity, and resistive index (RI) were measured in each pole of the operated and contralateral kidney separately before and at postoperative day (POD) 1, and at 3, 6, and 12 months after PNL.

RESULTS

The mean age of the patients was 36.67 +/- 14.68 years. The serum creatinine level increased significantly immediately after PNL but diminished to the preoperative level at POD 1. Changes in serum blood urea nitrogen and electrolyte levels were insignificant. Mean cortical thickness increased significantly in the access pole and contralateral kidney and insignificantly in the nonaffected pole. No statistically significant change was recorded in parenchymal echogenicitiy. Statistically significant differences in cortical thickness between the access pole and the contralateral kidney and between the nonaffected pole and the contralateral kidney disappeared 3 months later. Differences in mean cortical thickness between the access pole and the nonaffected pole were insignificant at all examination periods. Echogenicity was greater in the access pole and the nonaffected pole than in the contralateral kidney only at POD 1. No significant difference was noted in the echogenicity between the access pole and the nonaffected pole. Mean RIs were lower than the universally accepted pathologic RI level (0.70) at all periods. There was no statistically significant difference between the mean RI values of the access pole, nonaffected pole, and contralateral kidney.

CONCLUSION

PNL does not cause obvious renal dysfunction and significant parenchymal scarring, which is indicated by the decrease in cortical thickness and increases in cortical echogenicity and intrarenal RI.