title: Fiber density index in the evaluation of the spinal cord in patients with multiple sclerosis.
abstract: OBJECTIVE
  The aims of this study were to determine fractional anisotropy (FA) and the fibre density index (FDi) in the cervical spinal cord of patients with multiple sclerosis (MS) by using diffusion-tensor magnetic resonance imaging (DT-MRI) to identify possible differences between MS patients and controls.
  
  
  METHODS
  We studied 27 patients with MS - nine with primary progressive (PPMS), nine with secondary progressive (SPMS) and nine with relapsing-remitting (RRMS) disease - and 18 healthy individuals as controls. Conventional and DTI sequences with diffusion gradients applied in 32 directions were obtained. The results were compared between healthy controls and patients, between healthy controls and individual forms of MS and between the three forms of MS. Statistical analysis was performed by analysis of variance (ANOVA) and Student's t test.
  
  
  RESULTS
  The FDi in the three subgroups of patients and in controls showed a statistically significant difference. Using the t test, we found results from both PPMS and SPMS groups were different from controls. The correlation between FA and FDi was significant both in healthy controls and in MS patients evaluated as a single group.                                CONSLUCIONS:                  Despite the small group of patients, these findings suggest that FDi associated with FA is a sensitive parameter for assessing spinal cord damage in patients with MS.
authors: U.C.O. di Radiologia, Ospedale di Cattinara, Azienda Ospedaliero-Universitaria, Ospedale di Cattinara, Strada di Fiume 447, 34149, Trieste, Italy. majaukmar@alice.it
authors: M
authors: M
authors: Ukmar
authors: A
authors: A
authors: Montalbano
authors: E
authors: E
authors: Makuc
authors: I
authors: I
authors: Specogna
authors: A
authors: A
authors: Bratina
authors: R
authors: R
authors: Longo
authors: M A
authors: MA
authors: Cova
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016880:Anisotropy; D016022:Case-Control Studies; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology*; D013116:Spinal Cord / Q000473:pathology*