Use of sodium iodide to overcome the eluate age restriction for Ceretec reconstitution.

The Ceretec kit for preparation of 99Tcm-hexamethylpropyleneamine oxime (HMPAO) complex for the investigation of regional cerebral blood flow requires careful handling by the radiopharmacist and a number of restrictions have been placed on the kit relating to the nature of 99Tcm generator eluate used for reconstitution. The addition of sodium iodide to eluate immediately after elution can remove one of these restrictions. A level of 0.4 mg sodium iodide added after elution allows reconstitution of Ceretec up to 6 h later with no adverse effect on radiochemical purity. This offers a simple method for the use of this product if availability of fresh technetium generator eluate is a constraint.

Development of a 99Tcm-labelled radiopharmaceutical for cerebral blood flow imaging.

A new radiopharmaceutical, 99Tcm-hexamethylpropyleneamine oxime (99Tcm-HM-PAO) has shown considerable promise for single photon emission tomographic (SPECT) imaging of the brain. In animal biodistribution studies this complex demonstrates good brain uptake with prolonged retention of activity in brain. Further improvement of these properties, resulting in higher brain uptake with very slow washout and fixed regional distribution has been achieved following the isolation of the d,1-diastereoisomer of HM-PAO.