T. Tsuchida et al., SPECT IMAGES OF TECHNETIUM-99M-ETHYL CYSTEINATE DIMER IN CEREBROVASCULAR DISEASES - COMPARISON WITH OTHER CEREBRAL PERFUSION TRACERS AND PET, The Journal of nuclear medicine, 35(1), 1994, pp. 27-31
To assess the clinical role of Tc-99m-ethyl cysteinate dimer (ECD) as
a cerebral perfusion tracer, 10 patients with unilateral cerebral infa
rction were studied. Methods: ECD SPECT images were compared with IMP
and/or HMPAO SPECT in nine patients, seven in chronic phases and two i
n subacute phases. Five of these patients and one additional patient w
ith chronic infarction received PET imaging in order to compare ECD di
stribution with quantitative regional cerebral blood flow (rCBF) and o
xygen metabolism (rCMRO(2)) images. Results: In patients with chronic
cerebral infarction, regression analysis showed excellent correlation
between ECD and IMP in the uptake ratio of lesions-to-nonaffected cort
ices (r = 0.91). In two cases of subacute infarction, decreased uptake
of ECD was observed in the area of ''luxury perfusion,'' which showed
elevated or preserved rCBF with diminished rCMRO,. On visual analysis
, ECD image contrast was less prominent compared to that of IMP, but c
ontrast was better than that of HMPAO. Conclusions: ECD uptake showed
a curvilinear relationship against rCBF, suggesting flow-limited uptak
e in a high flow range. ECD is a clinically useful cerebral perfusion
tracer with distinct characteristics when compared with other availabl
e agents.