title: Evaluation of SWI in children with sickle cell disease.
abstract: OBJECTIVE
  SWI is a powerful tool for imaging of the cerebral venous system. The SWI venous contrast is affected by blood flow, which may be altered in sickle cell disease. In this study, we characterized SWI venous contrast in patients with sickle cell disease and healthy control participants and examined the relationships among SWI venous contrast, and hematologic variables in the group with sickle cell disease.
  
  
  METHODS
  A retrospective review of MR imaging and hematologic variables from 21 patients with sickle cell disease and age- and sex-matched healthy control participants was performed. A Frangi vesselness filter was used to quantify the attenuation of visible veins from the SWI. The normalized visible venous volume was calculated for quantitative analysis of venous vessel conspicuity.
  
  
  RESULTS
  The normalized visible venous volume was significantly lower in the group with sickle cell disease vs the control group (P < .001). Normalized visible venous volume was not associated with hemoglobin, percent hemoglobin F, percent hemoglobin S, absolute reticulocyte count, or white blood cell count. A hypointense arterial signal on SWI was observed in 18 of the 21 patients with sickle cell disease and none of the 21 healthy control participants.
  
  
  CONCLUSIONS
  This study demonstrates the variable and significantly lower normalized visible venous volume in patients with sickle cell disease compared with healthy control participants. Decreased venous contrast in sickle cell disease may reflect abnormal cerebral blood flow, volume, velocity, or oxygenation. Quantitative analysis of SWI contrast may be useful for investigation of cerebrovascular pathology in patients with sickle cell disease, and as a tool to monitor therapies. However, future studies are needed to elucidate physiologic mechanisms of decreased venous conspicuity in sickle cell disease.
authors.affiliation: From the Departments of Radiological Sciences (A.M.W., B.A.T., R.S., R.B.L., P.G., R.J.O., C.M.H., K.J.H.).
authors.forename: A M
authors.initials: AM
authors.lastname: Winchell
authors.affiliation: From the Departments of Radiological Sciences (A.M.W., B.A.T., R.S., R.B.L., P.G., R.J.O., C.M.H., K.J.H.).
authors.forename: B A
authors.initials: BA
authors.lastname: Taylor
authors.affiliation: From the Departments of Radiological Sciences (A.M.W., B.A.T., R.S., R.B.L., P.G., R.J.O., C.M.H., K.J.H.).
authors.forename: R
authors.initials: R
authors.lastname: Song
authors.affiliation: From the Departments of Radiological Sciences (A.M.W., B.A.T., R.S., R.B.L., P.G., R.J.O., C.M.H., K.J.H.).
authors.forename: R B
authors.initials: RB
authors.lastname: Loeffler
authors.affiliation: From the Departments of Radiological Sciences (A.M.W., B.A.T., R.S., R.B.L., P.G., R.J.O., C.M.H., K.J.H.).
authors.forename: P
authors.initials: P
authors.lastname: Grundlehner
authors.affiliation: Hematology (J.S.H., W.C.W.), St. Jude Children's Research Hospital, Memphis, Tennessee.
authors.forename: J S
authors.initials: JS
authors.lastname: Hankins
authors.affiliation: Hematology (J.S.H., W.C.W.), St. Jude Children's Research Hospital, Memphis, Tennessee.
authors.forename: W C
authors.initials: WC
authors.lastname: Wang
authors.affiliation: From the Departments of Radiological Sciences (A.M.W., B.A.T., R.S., R.B.L., P.G., R.J.O., C.M.H., K.J.H.).
authors.forename: R J
authors.initials: RJ
authors.lastname: Ogg
authors.affiliation: From the Departments of Radiological Sciences (A.M.W., B.A.T., R.S., R.B.L., P.G., R.J.O., C.M.H., K.J.H.).
authors.forename: C M
authors.initials: CM
authors.lastname: Hillenbrand
authors.affiliation: From the Departments of Radiological Sciences (A.M.W., B.A.T., R.S., R.B.L., P.G., R.J.O., C.M.H., K.J.H.) Kathleen.helton@stjude.org.
authors.forename: K J
authors.initials: KJ
authors.lastname: Helton
mesh_terms: D000465:Algorithms; D000755:Anemia, Sickle Cell / Q000473:pathology*; D002550:Cerebral Veins / Q000473:pathology*; D002648:Child; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity