Two-exponential analysis of spin-spin proton relaxation times in MR imaging using surface coils.
Proton relaxation time measurements were performed on a standard whole body MR imager operating at 1.5 T using a conventional surface coil of the manufacturer. A combined CP/CPMG multiecho, multislice sequence was used for the T1 and T2 relaxation time measurements. Two repetition times of 2000 ms (30 echoes) and 600 ms (2 echoes) with 180 degrees-pulse intervals of 2 tau = 22 ms were interleaved in this sequence. A two-exponential T2 analysis of each pixel of the spin-echo images was computed in a case of an acoustic neurinoma. The two-exponential images show a "short" component (T2S) due to white and gray matter and a "long" component (T2S) due to the cerebrospinal fluid. In the fatty tissue two components with T2S = 35 +/- 3 ms and T2L = 164 +/- 7 ms were measured. Comparing with Gd-DTPA imaging the relaxation time images show a clear differentiation of vital tumor tissue and cerebrospinal fluid.
Schad
L R
LR
Institute of Radiology and Pathophysiology, German Cancer Research Center, Heidelberg.
Brix
G
G
Semmler
W
W
Gückel
F
F
Lorenz
W J
WJ
D004867:Equipment Design; D005069:Evaluation Studies as Topic; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods; D011522:Protons; D013997:Time Factors
D011522:Protons