<prompt> Dye used in SPECT-O-14Tc-99Nitrogen-16Iodine 124  <response>: SPECT imaging: It has a 360deg revolving gamma camera giving 3D images Tc99m radioisotope is used t12 6 hrs Tc99m - HMPAO: LipophilicLipid soluble Crosses blood brain barrier Cerebral perfusion is evaluation 