A novel quantitative method for measuring obstruction in the upper urinary tract: The ‘obstruction coefficient’

Lovasz, Sandor; Lovász, László; Nyírády, Péter; Romics, Imre

doi:10.1111/j.1442-2042.2008.02043.x

Cited by 3 publications

(2 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This experimental method was implemented for a quantitative study, but the approach represents an invasive examination for patients with urinary tract dilatation without the need for nephrostomy, which is the main reason to limit the clinical application of this classical technique. Lovasz et al verified the authenticity and accuracy of the results of upper urinary tract urodynamic diagnosis in nephrostomy patients and tried to improve the experimental method for ascertaining upper urinary tract urodynamics [ 10 ], but invasive examination has not been widely used in the clinic. Therefore, in this study, experimental animals were modelled according to the classical CPP test, and multiphase volume data were collected and calculated by 640 layers of DVCT to find a noninvasive quantitative research method to calculate the urodynamics of the upper urinary tract.…”

Section: Discussionmentioning

confidence: 99%

Quantitative evaluation of upper urinary tract pump function in pigs with acute unilateral lower ureteral obstruction by 640-slice dynamic volume CT

Mao

Peng

et al. 2021

BMC Urol

View full text Add to dashboard Cite

Background It is a challenging problem to differentiate obstructive hydronephrosis from noninvasive evaluation of renal pelvis and ureteral motility in patients. The purpose of this study was to explore the value of 640-slice dynamic volume CT (DVCT) in the quantitative measurement of upper urinary tract (UUT) pump function after acute unilateral lower ureteral obstruction in pigs. Methods In this study, a perfusion pig model was constructed by constant pressure perfusion testing of the renal pelvis and left nephrostomy. The perfusion and pressure measuring devices were connected to create a state of no obstruction and acute obstruction of the lower part of the left ureter. After successful modelling, continuous dynamic volume scanning of the bilateral renal excretion phase was performed with 640-slice DVCT, and pump functions of the renal pelvis and part of the upper ureter were calculated and analysed. No obstruction or acute obstruction of the lower part of the left ureter was observed. Pump functions of the renal pelvis and part of the upper ureter were determined. Results The results showed that after LUUT fistulostomy, the time difference between the average UUT volume and positive volume value increased gradually, and the calculated flow velocity decreased, which was significantly different from that of the RUUT. The volume difference of the LUUT increased significantly in mild obstruction. In the bilateral control, the volume change rate of the LUUT increased with mild obstruction and decreased with severe obstruction, and there was a significant difference between the left and right sides. Conclusion The continuous dynamic volume scan and measurement of 640-slice DVCT can obtain five pump function datasets of UUT in pigs with acute lower ureteral obstruction.

show abstract

Section: Discussionmentioning

confidence: 99%

Quantitative evaluation of upper urinary tract pump function in pigs with acute unilateral lower ureteral obstruction by 640-slice dynamic volume CT

Mao

Peng

et al. 2021

BMC Urol

View full text Add to dashboard Cite

show abstract

“…This experimental method is a quantitative study, but this experiment is an invasive examination for patients with urinary tract dilatation without the need for nephrostomy, which is the main reason to limit the clinical application of this classical experiment. Lovasz S et al have verified the authenticity and accuracy of the results of upper urinary tract urodynamic diagnosis by nephrostomy patients, and tried to improve the experimental method of upper urinary tract urodynamics [10], but still invasive examination has not been widely used in clinic. Therefore, in this study, the experimental animals were modeled according to the classical CPP test, and the multi-phase volume data were collected and calculated by 640 layers of DVCT, in order to find a non-invasive quantitative research method of urodynamics of upper urinary tract.…”

Section: Data Processingmentioning

confidence: 99%

Quantitative Evaluation of Upper Urinary Tract Pump Function in Pigs With Acute Unilateral Lower Ureteral Obstruction by 640-slice Dynamic Volume CT

Mao

Peng

et al. 2021

Preprint

View full text Add to dashboard Cite

Background: It is a challenging problem to differentiate obstructive hydronephrosis from non-invasive evaluation of renal pelvis and ureteral motility in patients. The purpose of this study was to explore the value of 640-slice dynamic volume CT (DVCT) in quantitative measurement of upper urinary tract (UUT) pump function after acute unilateral lower ureteral obstruction in pigs. Methods: In this study, perfusion pig model was made by constant pressure perfusion test of renal pelvis and left nephrostomy. The perfusion and pressure measuring devices were connected to create the state of no obstruction, acute obstruction of the lower part of the left ureter. After successful modeling, continuous dynamic volume scanning of bilateral renal excretion phase was performed with 640-slice DVCT, and pump functions of the renal pelvis and part of the upper ureter were calculated and analyzed. No obstruction, acute obstruction of the lower part of the left ureter. Pump functions of the renal pelvis and part of the upper ureter. Results: Results showed after LUUT fistulostomy, the time difference between the average UUTs volume and positive volume value increased gradually, and the calculated flow velocity decreased, which was significantly different from that of the RUUT. The volume difference of the LUUT increased significantly in mild obstruction. In the bilateral control, the volume change rate of the LUUT increased in mild obstruction and decreased in severe obstruction, and there was significant difference between the left and the right side. Conclusion: The continuous dynamic volume scan and measurement of 640-slice DVCT can obtain five pump function data of UUT in pigs with acute lower ureteral obstruction.

show abstract

A modified Whitaker test (upper urinary tract videourodynamics) using for evaluating complex upper urinary tract reconstruction surgical effect

Yang¹,

Li²,

Xiao³

et al. 2021

Transl Androl Urol

View full text Add to dashboard Cite

Background: To evaluate the feasibility and effect of upper urinary tract videourodynamics in complex reconstructed upper urinary tract. Methods: From January 2016 to December 2018, patients who underwent complex upper urinary tract reconstruction and received upper urinary tract videourodynamics were included in the study. The modified Whitaker test was performed at 3 months after operation. The relative pelvic pressure was defined as the pelvic pressure minus the bladder pressure. Based on the flow rate, the test was divided into physiological phase and high flow phase. The results of pressure and image were classified into 3 types. Successful nephrostomy removal was defined as no symptoms and improved or stable hydronephrosis. Results: A total of 12 patients who underwent complex upper urinary tract reconstruction received modified Whitaker test. All tests were successfully completed without adverse reactions. The relative pelvic pressure of 3 patients kept steady near the baseline throughout the examination and was classified into type 1. The pelvic pressure of 7 patients increased as the perfusion continued, and the relative pressure dropped to relative low level due to the peristalsis of ureter (type 2). The pressure of 2 patients increased along with increasing perfusion speed, and the relative pelvis pressure could easily reach 15 cmH2O. The peristalsis of ureter disappeared or appeared very weakly on the video record (type 3). Patients in type 1 (3 cases) and type 2 (7 cases) groups were allowed to remove the nephrostomy tube immediately. Patients in type 3 group needed to keep the nephrostomy for close follow up, and the tubes were removed 2 weeks and 4 weeks after the examination, respectively. None of the 12 patients received further treatment for recurrent symptoms and exacerbation of hydronephrosis. Conclusions: The modified Whitaker test is initially safe and feasible in postoperative evaluation of complex upper urinary tract reconstruction surgery. Detailed results can provide more evidence to judge whether nephrostomy tube could be removed safely.

show abstract

A novel quantitative method for measuring obstruction in the upper urinary tract: The ‘obstruction coefficient’

Cited by 3 publications

References 26 publications

Quantitative evaluation of upper urinary tract pump function in pigs with acute unilateral lower ureteral obstruction by 640-slice dynamic volume CT

Quantitative evaluation of upper urinary tract pump function in pigs with acute unilateral lower ureteral obstruction by 640-slice dynamic volume CT

Quantitative Evaluation of Upper Urinary Tract Pump Function in Pigs With Acute Unilateral Lower Ureteral Obstruction by 640-slice Dynamic Volume CT

A modified Whitaker test (upper urinary tract videourodynamics) using for evaluating complex upper urinary tract reconstruction surgical effect

Contact Info

Product

Resources

About