title: Risk Factors for Femoral Head Deformity in the Early Stage of Legg-Calvé-Perthes Disease: MR Contrast Enhancement and Diffusion Indexes.
abstract: OBJECTIVE
  To determine whether changes in diffusion and/or contrast enhancement are of prognostic value in the early stage of Legg-Calvé-Perthes disease (LCPD).
  
  
  METHODS
  This study was approved by the institutional review board, and written informed consent was obtained from patient parents. Diffusion and contrast agent-enhanced magnetic resonance (MR) imaging studies were performed in 46 children (37 boys and nine girls; mean age, 7.5 years [age range, 3.3-11.9 years]) with unilateral LCPD at the early stage before development of extensive femoral head deformity. The degree of contrast enhancement was measured on the contrast-enhanced MR images, and the apparent diffusion coefficient (ADC) value was measured on the ADC map at various regions of interest in the proximal femur. The association of the MR imaging parameters that compared the affected side with the contralateral normal side with the femoral head deformity index value above 0.3 at 2 years was investigated.
  
  
  RESULTS
  Increased diffusion in the metaphysis (P = .003) and decreased contrast enhancement in the central epiphysis (P = .034) were the significant prognostic indicators of subsequent femoral head deformation. ADC in the metaphysis 45% higher and a contrast enhancement in the central epiphysis 37% lower than those of the contralateral normal side are associated with a nonfavorable prognosis. For diffusion MR imaging, sensitivity was 83% (15 of 18), specificity was 86% (24 of 28), positive predictive value was 79% (15 of 19), negative predictive value was 89% (24 of 27), and accuracy was 85% (39 of 46). For contrast-enhanced MR imaging, sensitivity was 78% (14 of 18), specificity was 64% (18 of 28), positive predictive value was 58% (14 of 24), negative predictive value was 82% (18 of 22), and accuracy was 70% (32 of 46).
  
  
  CONCLUSIONS
  Diffusion and contrast-enhanced MR imaging are potentially useful to assess risk of later development of femoral head deformity.
authors.affiliation: From the Division of Pediatric Orthopaedics, Seoul National University Children's Hospital, Seoul, Korea (W.J.Y., I.H.C., T.J.C., W.J.); Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea (C.Y.C., M.S.P.); Department of Orthopaedic Surgery, Gacheon University Gil Hospital, Incheon, Korea (E.S.C.); and Department of Radiology, Seoul National University Hospital, 101 Daehak-ro Jongno-gu, Seoul 110-744, Korea (J.E.C.).
authors.forename: Won Joon
authors.initials: WJ
authors.lastname: Yoo
authors.affiliation: From the Division of Pediatric Orthopaedics, Seoul National University Children's Hospital, Seoul, Korea (W.J.Y., I.H.C., T.J.C., W.J.); Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea (C.Y.C., M.S.P.); Department of Orthopaedic Surgery, Gacheon University Gil Hospital, Incheon, Korea (E.S.C.); and Department of Radiology, Seoul National University Hospital, 101 Daehak-ro Jongno-gu, Seoul 110-744, Korea (J.E.C.).
authors.forename: In Ho
authors.initials: IH
authors.lastname: Choi
authors.affiliation: From the Division of Pediatric Orthopaedics, Seoul National University Children's Hospital, Seoul, Korea (W.J.Y., I.H.C., T.J.C., W.J.); Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea (C.Y.C., M.S.P.); Department of Orthopaedic Surgery, Gacheon University Gil Hospital, Incheon, Korea (E.S.C.); and Department of Radiology, Seoul National University Hospital, 101 Daehak-ro Jongno-gu, Seoul 110-744, Korea (J.E.C.).
authors.forename: Tae-Joon
authors.initials: TJ
authors.lastname: Cho
authors.affiliation: From the Division of Pediatric Orthopaedics, Seoul National University Children's Hospital, Seoul, Korea (W.J.Y., I.H.C., T.J.C., W.J.); Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea (C.Y.C., M.S.P.); Department of Orthopaedic Surgery, Gacheon University Gil Hospital, Incheon, Korea (E.S.C.); and Department of Radiology, Seoul National University Hospital, 101 Daehak-ro Jongno-gu, Seoul 110-744, Korea (J.E.C.).
authors.forename: Wooyoung
authors.initials: W
authors.lastname: Jang
authors.affiliation: From the Division of Pediatric Orthopaedics, Seoul National University Children's Hospital, Seoul, Korea (W.J.Y., I.H.C., T.J.C., W.J.); Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea (C.Y.C., M.S.P.); Department of Orthopaedic Surgery, Gacheon University Gil Hospital, Incheon, Korea (E.S.C.); and Department of Radiology, Seoul National University Hospital, 101 Daehak-ro Jongno-gu, Seoul 110-744, Korea (J.E.C.).
authors.forename: Chin Youb
authors.initials: CY
authors.lastname: Chung
authors.affiliation: From the Division of Pediatric Orthopaedics, Seoul National University Children's Hospital, Seoul, Korea (W.J.Y., I.H.C., T.J.C., W.J.); Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea (C.Y.C., M.S.P.); Department of Orthopaedic Surgery, Gacheon University Gil Hospital, Incheon, Korea (E.S.C.); and Department of Radiology, Seoul National University Hospital, 101 Daehak-ro Jongno-gu, Seoul 110-744, Korea (J.E.C.).
authors.forename: Moon Seok
authors.initials: MS
authors.lastname: Park
authors.affiliation: From the Division of Pediatric Orthopaedics, Seoul National University Children's Hospital, Seoul, Korea (W.J.Y., I.H.C., T.J.C., W.J.); Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea (C.Y.C., M.S.P.); Department of Orthopaedic Surgery, Gacheon University Gil Hospital, Incheon, Korea (E.S.C.); and Department of Radiology, Seoul National University Hospital, 101 Daehak-ro Jongno-gu, Seoul 110-744, Korea (J.E.C.).
authors.forename: Eun-Seok
authors.initials: ES
authors.lastname: Choi
authors.affiliation: From the Division of Pediatric Orthopaedics, Seoul National University Children's Hospital, Seoul, Korea (W.J.Y., I.H.C., T.J.C., W.J.); Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea (C.Y.C., M.S.P.); Department of Orthopaedic Surgery, Gacheon University Gil Hospital, Incheon, Korea (E.S.C.); and Department of Radiology, Seoul National University Hospital, 101 Daehak-ro Jongno-gu, Seoul 110-744, Korea (J.E.C.).
authors.forename: Jung-Eun
authors.initials: JE
authors.lastname: Cheon
mesh_terms: D002648:Child; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D005270:Femur Head / Q000473:pathology*; D006801:Humans; D007873:Legg-Calve-Perthes Disease / Q000473:pathology*; D008297:Male; D008536:Meglumine; D009942:Organometallic Compounds; D011379:Prognosis; D012307:Risk Factors
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D008536:Meglumine; C072417:gadoterate meglumine