title: Surface-length index: a novel index for rapid detection of right ventricles with abnormal ejection fraction using cardiac MRI.
abstract: OBJECTIVE
  To validate a new index, the surface-length index (SLI) based on area change in a short-axis view and length reduction in the horizontal long-axis view, which is used to quickly (<1 min) detect right ventricles with an abnormal ejection fraction (EF) during a cardiac MRI examination. SLI can be used to avoid a complete delineation of the endocardial contours of normal right ventricles.
  
  
  METHODS
  Sixty patients (group A) were retrospectively included to calibrate the SLI formula by optimisation of the area under the ROC curves and SLI thresholds were chosen to obtain 100 % sensitivity. Another 340 patients (group B) were prospectively recruited to test SLI's capacity to detect right ventricles (RVs) with an abnormal EF (<0.5).
  
  
  RESULTS
  The appropriate threshold to obtain 100 % sensitivity in group A was 0.58. In group B, with the 0.58 threshold, SLI yielded a sensitivity of 100 % and specificity of 51 %. SLI would have saved 35 % of the RV studies in our population, without inducing any diagnostic error. SLI and EF correlation was good (r (2) = 0.64).
  
  
  CONCLUSIONS
  SLI combines two simple RV measures, and brings significant improvement in post-processing efficiency by preselecting RVs that require a complete study.
  
  
  CONCLUSIONS
  • Assessment of right ventricle ejection fraction (RVEF) with cine-MRI is time consuming. • Therefore, RVEF is not always assessed during cardiac MRI. • Surface-length index (SLI) allows rapid detection of abnormal RVEF during cardiac MRI. • SLI saves one third of the operator time. • Every cardiac MRI could include RVEF assessment by means of SLI.
authors: CHU Nancy, Departments of Cardiology and Medical Imaging and INSERM (IADI U947, CICIT 801 and U684), Rue du Morvan, 54511, Vandoeuvre les nancy, France, l.bonnemains@chu-nancy.fr.
authors: Laurent
authors: L
authors: Bonnemains
authors: Damien
authors: D
authors: Mandry
authors: Anne
authors: A
authors: Menini
authors: Bertrand
authors: B
authors: Stos
authors: Jacques
authors: J
authors: Felblinger
authors: Pierre-Yves
authors: PY
authors: Marie
authors: Pierre-Andre
authors: PA
authors: Vuissoz
mesh_terms: D000328:Adult; D000465:Algorithms; D019540:Area Under Curve; D002138:Calibration; D005260:Female; D006352:Heart Ventricles / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018497:Ventricular Dysfunction, Right / Q000175:diagnosis / Q000473:pathology
references: Eur Radiol. 2011 Dec;21(12):2492-502
references: 21792616
references: Eur Radiol. 2003 Jun;13(6):1387-93
references: 12764656
references: Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu. 2006;:3-10
references: 16638541
references: Radiology. 2011 Jul;260(1):88-97
references: 21460029
references: Int J Cardiovasc Imaging. 2009 Oct;25(7):689-97
references: 19634000
references: Eur Radiol. 2012 May;22(5):1041-9
references: 22270140
references: Magn Reson Med. 2012 Jun;67(6):1740-6
references: 22135141
references: J Am Soc Echocardiogr. 2011 Jun;24(6):637-43
references: 21392939
references: Am Heart J. 1984 Mar;107(3):526-31
references: 6695697
references: Eur Radiol. 2004 Oct;14(10):1813-22
references: 15258823
references: Circulation. 2002 Jan 29;105(4):539-42
references: 11815441
references: Heart. 2010 Feb;96(4):281-8
references: 19720609
references: Eur Heart J. 2006 Dec;27(23):2879-88
references: 17088316
references: Eur Heart J Cardiovasc Imaging. 2012 Mar;13(3):235-42
references: 22127626
references: Lancet. 1986 Feb 8;1(8476):307-10
references: 2868172
references: J Am Coll Cardiol. 2010 Jun 8;55(23):2614-62
references: 20513610
references: Echocardiography. 1997 Mar;14(2):189-206
references: 11174944
references: J Cardiovasc Magn Reson. 2009 Jun 21;11:19
references: 19545393
references: Arch Cardiovasc Dis. 2009 Mar;102(3):219-32
references: 19375676
references: J Am Soc Echocardiogr. 1989 Mar-Apr;2(2):110-8
references: 2629860
references: Am J Cardiol. 1996 Dec 1;78(11):1317-21
references: 8960603
references: Chest. 1980 Mar;77(3):390-5
references: 7357942
references: Eur J Echocardiogr. 2010 Mar;11(2):81-96
references: 20124362
references: J Biomed Eng. 1993 Mar;15(2):127-31
references: 8459690
references: Circulation. 1973 Jan;47(1):144-53
references: 4686591