normal subjects and 250 patients with thyroid disease were performed thyroid imaging. The parameters reflecting the function of thyroid were calculated

including rectified ratio(RR)

uptake ratio(UR) and 99m Tc percentage uptake(PU).The identity between RR and PU was compared with the identify between UR and PU. The parameters in disease groups were also compared with that of normal group. The results showed that the real identify percentage (95.6%) between RR and PU was significantly higher than that of UR and PU (77.9%) ( χ 2=40.9

P <0.001). RR were significantly higher in groups of hyperthyroidism and recurrence after thyroidectomy than normal group ( P <0.05-0.005)

and significantly lower in subacute thyroiditis group ( P <0.001).RR may be normal or increased in simple goiter and may be normal

increased or decreased in hypothyroidism. Thereby

RR is obviously better than UR in determining the level of thyroid 99m Tc uptake. It is difficult in discriminating between hyperthyroidism and hypothyroidism by RR

but it still has important significance in correlation with clinical and other examination data for comprehansive judgement.