Hon J. Yu1, Shadfar Bahri1, Lutfi Tugan Muftuler1, Orhan Nalcioglu1, Vance Gardner2
1Tu & Yuen Center for Functional Onco-Imaging, University of California, Irvine, CA, USA; 2Orthopaedic Education and Research Institute of Southern California, Orange, CA, USA
The level of degeneration was graded on 5-level Pfirrmann classification system and its correlation with ADC values was investigated in vivo using 166 lumbar intervertebral discs (IVD). The ADC values from the whole IVD were obtained on a pixel-by-pixel basis and then grouped for each Pfirrman grade for comparison. The mean population values of ADC amongst the 5 groups differed significantly and showed an inversely proportional trend with respect to the grades (1: normal; 5: severe degeneration). A 5-bin histogram analysis of the ADC values exhibited a characteristic distribution of ADC values for each group, perhaps revealing different degenerative-related changes taking place in nucleus pulposus and annulus fibrosus of IVD.