99mTc-ECD SPECT is valuable for the evaluation of cell viability and function. The purpose of the present study was to evaluate the significance of
99mTc-ECD brain SPECT in
ischemic stroke. We compared
99mTc-ECD brain SPECT with perfusion and diffusion weighted images (PWI, DWI). Ten patients with acute and early subacute
ischemic stroke were included in this prospective study. T2-weighted images (T2WI), DWI, PWI and
99mTc-ECD SPECT were obtained during both the acute/early subacute and late subacute stages. In the case of PWI, time to peak (
TTP) and regional cerebral blood volume (rCBV) maps were obtained. The rCBV map and
99mTc-ECD SPECT images were compared in 8 lesions using DeltaAI. The asymmetry index (AI) was calculated as (Ci - Cc) X 200 / (Ci + Cc); where Ci is the mean number of pixel counts of an ipsilateral lesion and Cc is the mean number of pixel counts of the normal contralateral hemisphere. DeltaAI was defined as AIacute - AIsubacute in the ischemic core and periphery. PWI and
99mTc-ECD SPECT detected new lesions of the hyperacute stage or of evolving
stroke more accurately than T2WI and DWI.
99mTc-ECD SPECT was able to localize the
infarct core and peri-
infarct ischemia in all lesions in both the acute and the subacute stages. DeltaAI was higher in the rCBV map than in the
99mTc-ECD SPECT images in the ischemic core (p = 0.063) and in the periphery (p = 0.091). In the
99mTc-ECD SPECT images, DeltaAI was higher in the ischemic core than in the periphery (p = 0.028). During the subacute stage,
99mTc-ECD SPECT detected all the lesions without the pseudonormalization seen in the MR images of 5/11 lesions. Based on this study,
99mTc-ECD SPECT is comparable to PWI in terms of its ability to detect
acute stroke and is more useful than PWI in the case of subacute
infarction.