MR imaging of experimental intramuscular hemorrhage at 0.02 T. Contrast enhancement with Gd-DOTA.
Intramuscular hemorrhage was induced by injecting autologous blood into the paraspinal muscle of 8 rabbits. In order to evaluate the time-dependent changes of hemorrhage observed on MRI, the animals were imaged at different stages of blood resolution at 0.02 tesla (T), and control examined with ultrasound using a 7.5 MHz linear transducer. Six inversion recovery sequences (TR = 1,000 ms. TE = 30 ms, and TI = 18, 48, 148, 201, 302, and 398 ms) were used for the in vivo calculation of T1 relaxation times. IR 1,000 (398)/30 imaging was performed before and after the Gd-DOTA administration. The hemorrhage was evident on MR images throughout the study, especially on the T2 weighted (SE 1,000/100) images. MRI showed the healing lesion longer than ultrasound. The T1 relaxation time increased during the time of resolution. Lesions on days 4 to 7 enhanced in intensity after the injection of Gd-DOTA.
Niemi
P
P
Department of Diagnostic Radiology, University of Turku, Finland.
Paajanen
H
H
Kormano
M
M
Alanen
A
A
Määttänen
H
H
Dean
P B
PB
D000818:Animals; D006470:Hemorrhage / Q000473:pathology*; D006571:Heterocyclic Compounds; D008279:Magnetic Resonance Imaging; D009135:Muscular Diseases / Q000473:pathology*; D009942:Organometallic Compounds; D011817:Rabbits; D011856:Radiographic Image Enhancement
D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate