title: Acoustic radiation force impulse (ARFI) elastography in the evaluation of renal parenchymal stiffness in patients with ureteropelvic junction obstruction.
abstract: OBJECTIVE
  To investigate the role of acoustic radiation force impulse (ARFI) elastography in the detection of renal parenchymal damage in kidneys with and without ureteropelvic junction obstruction (UPJO).
  
  
  METHODS
  Twenty-five pediatric patients with a diagnosis of UPJO who underwent surgery and 15 pediatric patients with conservatively managed UPJO were prospectively evaluated with ARFI elastography. Sixteen healthy volunteers constituted the control group. Shear wave velocity (SWV) measurements in the upper, mid, and lower poles of the affected kidney were performed. SWV values of kidneys based on presence of UPJO and hydronephrosis grade were compared. The correlation of SWV values with residual renal function obtained from diethylenetriaminepentaacetic acid or mercaptoacetyltriglycine-3 renal scan was evaluated.
  
  
  RESULTS
  Significantly, higher SWV values were found in control kidneys compared to kidneys affected by UPJO. The median SWVs were 2.82 (2.51-3.07) m/s for the control kidneys and 2.36 (2.09-2.53) m/s for the kidneys in the UPJO group (p < 0.001). When UPJO patients were grouped according to the grade of hydronephrosis, grade 0 hydronephrotic kidneys [2.35 (2.11-2.50) m/s] and grade 3-4 hydronephrotic kidneys [1.86 (1.96-2.25) m/s] had significantly lower SWV values compared to grade 1-2 hydronephrotic kidneys [2.62 (2.37-2.90) m/s] (p < 0.05).
  
  
  CONCLUSIONS
  ARFI as a noninvasive, radiation-free procedure for evaluating parenchymal stiffness may prove useful in the diagnostic work-up and follow-up of children with UPJO-induced renal disease.
authors.affiliation: Department of Radiology, Istanbul University Cerrahpasa Medical Faculty, Istanbul, Turkey.
authors.forename: Hatice Arioz
authors.initials: HA
authors.lastname: Habibi
authors.affiliation: Department of Pediatric Nephrology, Istanbul University Cerrahpasa Medical Faculty, Istanbul, Turkey.
authors.forename: Rumeysa Yasemin
authors.initials: RY
authors.lastname: Cicek
authors.affiliation: Department of Radiology, Istanbul University Cerrahpasa Medical Faculty, Istanbul, Turkey. gskandemirli@yahoo.com.
authors.forename: Sedat Giray
authors.initials: SG
authors.lastname: Kandemirli
authors.affiliation: Department of Radiology, Istanbul University Cerrahpasa Medical Faculty, Istanbul, Turkey.
authors.forename: Emel
authors.initials: E
authors.lastname: Ure
authors.affiliation: Department of Radiology, Istanbul University Cerrahpasa Medical Faculty, Istanbul, Turkey.
authors.forename: Ayse Kalyoncu
authors.initials: AK
authors.lastname: Ucar
authors.affiliation: Department of Radiology, Istanbul University Cerrahpasa Medical Faculty, Istanbul, Turkey.
authors.forename: Mine
authors.initials: M
authors.lastname: Aslan
authors.affiliation: Department of Pediatric Nephrology, Istanbul University Cerrahpasa Medical Faculty, Istanbul, Turkey.
authors.forename: Salim
authors.initials: S
authors.lastname: Caliskan
authors.affiliation: Department of Radiology, Istanbul University Cerrahpasa Medical Faculty, Istanbul, Turkey.
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Adaletli
mesh_terms: D002648:Child; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging*; D007674:Kidney Diseases / Q000150:complications / Q000000981:diagnostic imaging*; D008297:Male; D015588:Observer Variation; D011446:Prospective Studies; D015203:Reproducibility of Results; D014517:Ureteral Obstruction / Q000150:complications / Q000000981:diagnostic imaging* / Q000628:therapy
keywords: Acoustic radiation force impulse; Elastography; Hydronephrosis; Ureteropelvic junction obstruction