title: Fetal MRI with diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) assessment in the evaluation of renal development: preliminary experience in normal kidneys.
abstract: OBJECTIVE
  The study aimed to investigate the correlation between apparent diffusion coefficient (ADC) and gestational age by applying diffusion-weighted imaging (DWI) in the study of normal fetal kidneys.
  
  
  METHODS
  We performed magnetic resonance (MR) imaging on 88 fetuses (gestational age range 17-40 weeks) after ultrasound had ruled out urinary system malformations. A multiplanar study of the urinary system was obtained by using conventional T2-weighted sequences and echoplanar imaging (EPI). DW sequences with ADC maps were subsequently acquired, and kidney ADC values were correlated with gestational age by diving the fetuses into six groups according to age.
  
  
  RESULTS
  We found a correlation between ADC values and gestational age. The ADC values, ranging from 0.99 to 1.62x10(-3) mm(2)/s [mean 1.22; 95% confidence interval (CI) 1.19-1.25, standard deviation (SD) 0.147], showed a tendency to decrease with increasing gestational age. The relationship between ADC values and gestational age was expressed by a linear regression equation: ADC (mm(2)/s)=1.69-0.0169 (GA) (R(2)=37.7%, R(2) ADJ=37.0%, p<0.005, Pearson correlation=-0.614).
  
  
  CONCLUSIONS
  DWI with ADC mapping provides functional information on fetal renal parenchyma development and may thus become a useful tool in the management of pregnancy and treatment of the newborn child.
authors.affiliation: Istituto di Scienze Radiologiche-Policlinico Umberto I, Università degli Studi Sapienza Roma, 00161, Roma, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Manganaro
authors.forename: A
authors.initials: A
authors.lastname: Francioso
authors.forename: S
authors.initials: S
authors.lastname: Savelli
authors.forename: A
authors.initials: A
authors.lastname: Tomei
authors.forename: F
authors.initials: F
authors.lastname: Fierro
authors.forename: M
authors.initials: M
authors.lastname: Di Maurizio
authors.forename: F
authors.initials: F
authors.lastname: Coratella
authors.forename: A
authors.initials: A
authors.lastname: Perrone
authors.forename: L
authors.initials: L
authors.lastname: Ballesio
authors.forename: A
authors.initials: A
authors.lastname: Giancotti
authors.forename: L
authors.initials: L
authors.lastname: Porfiri
authors.forename: M
authors.initials: M
authors.lastname: Marini
mesh_terms: D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005260:Female; D005865:Gestational Age; D006801:Humans; D007668:Kidney / Q000196:embryology*; D011247:Pregnancy