Introduction

Ureteral jet dynamics, which have been shown to indicate stone formation mechanism in adults and children in recent studies, provide information about ureteral peristaltism (1,2).

Case Presentation

We prospectively evaluated a 26-year-old male patient with a non-obstructive lower pole stone in the right kidney and a non-obstructive upper pole stone in the left kidney measuring

<1 cm who underwent non-contrast computed tomography due to intermittent flank pain (Figure 1). Metabolic evaluation of 24 h-urine collection test, urinalysis and blood-creatinine level were found to be within the normal ranges. A radiologist performed Doppler ultrasonography (D-US) for the assessment of ureteral jet dynamics. D-US was performed with the patient in the supine position with full bladder after hydration with water, using a 3-5 MHz convex probe with angle correction (Philips HDI 5000; Bothell, WA). A sample volume with an axial length of 2 mm was used and the wall filter was between 50 and 100 Hz for D-US measurements.

Parameters were average and maximum jet-flow rate (JETave and JETmax), duration of jet-flow (JETtime) and jet-flow pattern (JETpattern), the latter described by Leung et al. (3,4). The images are given in Figure 1.

Written informed consent was taken from the patient before the procedure.

Discussion

In recent studies, the association between non-obstructive kidney stones and ureteral jet dynamics was evaluated in adult and pediatric stone formers and JETave was found to be significantly lower in affected renal units and continuous JETpattern rate was found to be higher in affected renal units when compared with healthy renal units (1,2). Also, in a renal units with a JETave of <9.5 cm/sec for children and <9 cm/sec for adults were 5.6 and 19.3 times more likely to have a kidney stone, respectively. In the current patient, the JETave was found to be <9 cm/sec and the JETpattern was continuous for bilateral ureters. Low JETave and continuous JETpattern of bilateral renal units were similar to that in the above mentioned studies. Therefore, ureteral jet dynamics may also be included to the evaluation of stone formers.

In conclusion, decreased peristaltism measured with D-US included <9 cm/sec JETave and continuous Jetpattern, which may be an explanation for stone formation mechanism in adults.

Ethics

Informed Consent: Written informed consent was taken from the patient before the procedure.

Peer-review: Externally peer-reviewed.

Authorship Contributions

Concept: S.Ç., C.A., Design: S.Ç., C.A., Data Collection or Processing: S.Ç., C.A., G.U., Analysis or Interpretation: S.Ç., O.B., Ö.D., M.S., Literature Search: S.Ç., C.A., O.B., Writing: S.Ç.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study received no financial support.