title: Quantitative Diffusion Tensor Imaging Analysis of Low-Grade Gliomas: From Preclinical Application to Patient Care.
abstract: BACKGROUND
  Preoperative diffusion tensor tractography (DTT) has recently been used to aid in the mapping of functional pathways to limit damage associated with resection of low-grade gliomas (LGGs).
  
  
  OBJECTIVE
  To assess the predictive capacity of DTT as a biomarker of postoperative motor outcomes in patients with LGGs involving the corticospinal tract (CST). CST parameters obtained using a quantitative fiber tracking approach were used to investigate the reliability of the DTT biomarker by comparing their values in the tumoral (Tcst) and healthy (Hcst) hemispheres.
  
  
  METHODS
  Thirty-seven patients with LGGs involving the CST were enrolled. Quantification of structural differences between the Tcst and Hcst were analyzed according to the novel biomarker (NF index), defined as follows: (Hcst NF - Tcst NF)/Hcst NF, where NF represents the number of fibers in each region. Logistic regression analysis was used to examine associations among clinical postoperative outcomes and NF index values, tumoral patterns, and premotor/motor evoked potentials.
  
  
  RESULTS
  NF values significantly differed between the Tcst and Hcst. Analysis of the NF index showed that patients with a preoperative NF index <0.22 had a significantly lower risk of developing transient postoperative deficits (area under the curve, 0.92; 95% binomial confidence interval, 0.834-1). Patients with less pronounced differences in NF between the Tcst and Hcst also experienced better clinical outcomes.
  
  
  CONCLUSIONS
  The NF index may be a useful biomarker for predicting clinical outcomes in patients with LGGs. Furthermore, the NF index may provide a preoperative estimate of the patient's potential for recovery from possible postsurgical neurologic deficits.
authors.affiliation: Department of Neurosurgery, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia, Udine, Italy. Electronic address: tamara.ius@gmail.com.
authors.forename: Tamara
authors.initials: T
authors.lastname: Ius
authors.affiliation: CIMeC - Center for Mind/Brain Sciences, University of Trento, Trento, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Turella
authors.affiliation: Department of Neurology, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia, Udine, Italy.
authors.forename: Giada
authors.initials: G
authors.lastname: Pauletto
authors.affiliation: Department of Medical and Biological Sciences, Section of Statistics, University of Udine, Udine, Italy.
authors.forename: Miriam
authors.initials: M
authors.lastname: Isola
authors.affiliation: Department of Physics, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia, Udine, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Maieron
authors.affiliation: Department of Neurosurgery, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia, Udine, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Sciacca
authors.affiliation: Department of Neurology, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia, Udine, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Budai
authors.affiliation: Department of Neuroradiology, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia, Udine, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: D'Agostini
authors.affiliation: Department of Neurology, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia, Udine, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Eleopra
authors.affiliation: Department of Neurosurgery, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia, Udine, Italy.
authors.forename: Miran
authors.initials: M
authors.lastname: Skrap
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000601:surgery*; D015897:Comorbidity; D056324:Diffusion Tensor Imaging / Q000706:statistics & numerical data*; D042241:Early Diagnosis; D005260:Female; D005910:Glioma / Q000453:epidemiology / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009069:Movement Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control; D060787:Neoplasm Grading; D018802:Patient-Centered Care / Q000379:methods; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control; D011300:Preoperative Care; D015995:Prevalence; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D066127:White Matter / Q000000981:diagnostic imaging / Q000473:pathology; D055815:Young Adult
keywords: Brain mapping; Diffusion tensor imaging analysis; Extent of resection; Intraoperative electric stimulation; Low-grade gliomas; Motor evoked potentials