Brain perfusion with 99mTc-ECD shows bilateral temporoparietal hypoperfusion.
Different perfusion patterns have the following probabilities of AD:
Holman BL, Johnson KA, Gerada B et-al. The scintigraphic appearance of Alzheimer's disease: a prospective study using technetium-99m-HMPAO SPECT. J. Nucl. Med. 1992;33 (2): 181-5. J. Nucl. Med.Case " Alzheimer's disease - SPECT " courtesy of Dr Carlos Eduardo Anselmi,radiopaedia.org