title: Value of renal cortical thickness as a predictor of renal function impairment in chronic renal disease patients.
abstract: OBJECTIVE
  To determine the presence of linear relationship between renal cortical thickness, bipolar length, and parenchymal thickness in chronic kidney disease patients presenting with different estimated glomerular filtration rates (GFRs) and to assess the reproducibility of these measurements using ultrasonography.
  
  
  METHODS
  Ultrasonography was performed in 54 chronic renal failure patients. The scans were performed by two independent and blinded radiologists. The estimated GFR was calculated using the Cockcroft-Gault equation. Interobserver agreement was calculated and a linear correlation coefficient (r) was determined in order to establish the relationship between the different renal measurements and estimated GFR.
  
  
  RESULTS
  The correlation between GFR and measurements of renal cortical thickness, bipolar length, and parenchymal thickness was, respectively, moderate (r = 0.478; p < 0.001), poor (r = 0.380; p = 0.004), and poor (r = 0.277; p = 0.116). The interobserver agreement was considered excellent (0.754) for measurements of cortical thickness and bipolar length (0.833), and satisfactory for parenchymal thickness (0.523).
  
  
  CONCLUSIONS
  The interobserver reproducibility for renal measurements obtained was good. A moderate correlation was observed between estimated GFR and cortical thickness, but bipolar length and parenchymal thickness were poorly correlated.
authors: MD, Radiologist, Collaborator at Unit of Radiology and Imaging Diagnosis, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
authors: Samia Rafael
authors: SR
authors: Yamashita
authors: PhD, Radiologist, Collaborator at Department of Imaging Diagnosis, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Assistant Professor at Universidade do Vale do Sapucaí (Univás), Pouso Alegre, MG, Brazil.
authors: Augusto Castelli
authors: AC
authors: von Atzingen
authors: PhD, Research Physician Assistant, Department of Imaging Diagnosis, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp) and Centro Cochrane do Brasil, São Paulo, SP, Brazil.
authors: Wagner
authors: W
authors: Iared
authors: PhD, Associate Professor of Imaging Sciences, Universidade de Brasília (UnB), Brasília, DF, Brazil.
authors: Alexandre Sérgio de Araújo
authors: AS
authors: Bezerra
authors: PhD in Nephrology, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
authors: Adriano Luiz
authors: AL
authors: Ammirati
authors: PhD, Associate Professor, Division of Nephrology, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil.
authors: Maria Eugênia Fernandes
authors: ME
authors: Canziani
authors: Private Docent, Unit of Radiology and Imaging Diagnosis, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp) and Laboratório Fleury, São Paulo, SP, Brazil.
authors: Giuseppe
authors: G
authors: D'Ippolito
keywords: Chronic renal disease; Chronic renal failure; Glomerular filtration rate; Renal cortex; Ultrasonography