PURPOSE: To measure the proton density (PD), the T1 and T2 relaxation time, and magnetization transfer (MT) effects in human median nerve at 3 T and to compare them with the corresponding values in muscle. MATERIALS AND METHODS: Measurements of the T1 and T2 relaxation time were performed with an inversion recovery and a Carr-Purcell-Meiboom-Gill (CPMG) imaging sequence, respectively. The MT ratio was measured by acquiring two sets of 3D spoiled gradient-echo images, with and without a Gaussian saturation pulse. RESULTS: The median nerve T1 was 1410 +/- 70 msec. The T2 decay consisted of two components, with average T2 values of 26 +/- 2 msec and 96 +/- 3 msec and normalized amplitudes of 78 +/- 4% and 22 +/- 4%, respectively. The dominant component is likely to reflect myelin water and connective tissue, and the less abundant component originates possibly from intra-axonal water protons. The value of proton density of MRI-visible protons in median nerve was 81 +/- 3% that of muscle. The MT ratio in median nerve (40.3 +/- 2.0%) was smaller than in muscle (45.4 +/- 0.5%). CONCLUSION: MRI-relevant properties, such as PD, T1 and T2 relaxation time, and MT ratio were measured in human median nerve at 3 T and were in many respects similar to those of muscle.
PURPOSE: To measure the proton density (PD), the T1 and T2 relaxation time, and magnetization transfer (MT) effects in human median nerve at 3 T and to compare them with the corresponding values in muscle. MATERIALS AND METHODS: Measurements of the T1 and T2 relaxation time were performed with an inversion recovery and a Carr-Purcell-Meiboom-Gill (CPMG) imaging sequence, respectively. The MT ratio was measured by acquiring two sets of 3D spoiled gradient-echo images, with and without a Gaussian saturation pulse. RESULTS: The median nerve T1 was 1410 +/- 70 msec. The T2 decay consisted of two components, with average T2 values of 26 +/- 2 msec and 96 +/- 3 msec and normalized amplitudes of 78 +/- 4% and 22 +/- 4%, respectively. The dominant component is likely to reflect myelin water and connective tissue, and the less abundant component originates possibly from intra-axonal water protons. The value of proton density of MRI-visible protons in median nerve was 81 +/- 3% that of muscle. The MT ratio in median nerve (40.3 +/- 2.0%) was smaller than in muscle (45.4 +/- 0.5%). CONCLUSION: MRI-relevant properties, such as PD, T1 and T2 relaxation time, and MT ratio were measured in human median nerve at 3 T and were in many respects similar to those of muscle.
Authors: Lukas Filli; Marco Piccirelli; David Kenkel; Andreas Boss; Andrei Manoliu; Gustav Andreisek; Himanshu Bhat; Val M Runge; Roman Guggenberger Journal: Eur Radiol Date: 2015-09-15 Impact factor: 5.315
Authors: Jennifer Kollmer; Ute Hegenbart; Christoph Kimmich; Ernst Hund; Jan C Purrucker; John M Hayes; Stephen I Lentz; Georges Sam; Johann M E Jende; Stefan O Schönland; Martin Bendszus; Sabine Heiland; Markus Weiler Journal: Ann Clin Transl Neurol Date: 2020-04-25 Impact factor: 4.511