title: Ultrasonographic evaluation of disturbances in the perfusion of renal graft parenchyma as a result of acute occlusion of supernumerary arteries - a new application for contrast-enhanced ultrasonography.
abstract: BACKGROUND
  The aim of this study was to assess the disturbances in perfusion of transplanted kidneys (KTx) following an acute occlusion of 1 of the supernumerary renal arteries (SRA). We compared the differences in echogenicity and the size of ischemic areas between routine B mode ultrasonography with Doppler evaluation (US-CD) and contrast-enhanced ultrasound examination (CE-US).
  
  
  METHODS
  We present 4 KTx patients in whom we observed an occlusion of the SRA. After the initial diagnosis of occlusion of SRA in routine B mode with US-CD, the CE-US examination following intravenous contrast administration was performed. The disturbances of tissue perfusion in regions of interest, the level of signal intensity, and the size of the infarct were analyzed.
  
  
  RESULTS
  The renal parenchyma in the routine B mode was characterized by low echogenicity. After the contrast medium administration, we observed increased echogenicity (-53.75±5.3 dB vs. -28.75±3.8 dB, p<0.001). The echogenicity between the focus of the infarct and normal parenchyma in the routine B mode and US-CD was small, but the difference was larger for analogous areas in the CE-US (the mean signal intensity: -2.75±1.5 dB in the B mode/US-CD vs. -24.25±3.9 dB in CE-US, p<0.001). The size of the ischemic areas in the B mode and Doppler examinations were underestimated due to poor separation of the ischemic foci, and were much better visualized in the CE-US (-25.5±7.3 mm vs. -38.5±9.7 mm, p<0.001).
  
  
  CONCLUSIONS
  CE-US may enable a precise evaluation of a graft's ischemic foci due to occlusion of SRA in the early post-transplant period.
authors.affiliation: Department of Radiology and Diagnostic Imaging, Medical University of Lodz, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Grzelak
authors.forename: Ilona
authors.initials: I
authors.lastname: Kurnatowska
authors.forename: Michał
authors.initials: M
authors.lastname: Sapiecha
authors.forename: Adam
authors.initials: A
authors.lastname: Durczynski
authors.forename: Janusz
authors.initials: J
authors.lastname: Strzelczyk
authors.forename: Michal
authors.initials: M
authors.lastname: Nowicki
authors.forename: Ludomir
authors.initials: L
authors.lastname: Stefanczyk
mesh_terms: D000328:Adult; D003287:Contrast Media; D005260:Female; D006801:Humans; D007668:Kidney / Q000098:blood supply / Q000000981:diagnostic imaging; D016030:Kidney Transplantation / Q000009:adverse effects* / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000000981:diagnostic imaging* / Q000209:etiology*; D012078:Renal Artery Obstruction / Q000000981:diagnostic imaging* / Q000209:etiology*; D018615:Ultrasonography, Doppler, Color
chemical_list: D003287:Contrast Media