Abstract
This paper describes a study on the effect of structural differences in collagen fibers on the spin-spin (T2) relaxation and the apparent diffusion coefficient (ADC) of water molecules. Two collagen gels were polymerized from a type-I collagen solution with and without a 4.7 T magnetic field. The T2 relaxation time was measured by the Carr-Purcell-Meiboom-Gill (CPMG) sequence. The ADCs were measured using a stimulated echo sequence with motion probing gradient (MPG) pulses. The temperature in the bore was 15 degrees Celsius. The T2 relaxation times of water molecules in the collagen gels with magnetically oriented fibers and randomly oriented fibers were T2 = 0.52 s and T2 = 1.32 s, respectively. The ADCs of water molecules measured with MPG directions parallel and perpendicular to the collagen fibers were ADC = 2.08 × 10-9 m2/s and ADC = 1.92 × 10-9 m2/s, respectively. These differences are attributed to a change of collagen fiber structures due to the magnetic orientation.
