Technetium‐99m‐anti‐tumour necrosis factor alpha scintigraphy as promising predictor of response to corticotherapy in chronic active Graves' ophthalmopathy

It has been suggested that technetium‐99m (99mTc)‐anti‐tumour necrosis factor alpha (TNF‐α) scintigraphy (SCI) may be a useful diagnostic tool in Graves' ophthalmopathy (GO). This study evaluated whether orbit total radioactivity uptake on SCI could be used to predict corticosteroid therapy (CorT) responses in active‐GO patients. A longitudinal study of patients with active GO defined by Clinical Active Score (CAS) >3/7 was done. Clinical, laboratory and SCI evaluations were performed at baseline and 3 months after concluding intravenous CorT. SCI (planar and tomographic) was assessed after intravenous injection of 10 mCi of 99mTc‐anti‐TNF‐α. Orbits and cerebral hemispheres were defined as regions of interest (ROIs) to enable orbit/hemisphere ROI‐ratios of total radioactive uptake. ROI‐ratios were considered positive at >2·5. Average total radiation uptake (TRU) was also determined for each orbit (AVG_ROI). Clinical, laboratory and SCI data were compared between responders (CAS became inactive) and non‐responders to CorT (18 patients). At baseline, AVG_ROI were higher in active OG orbits (67·3 cps) than in inactive ones (33·6 cps; P<0·05). AVG_ROI (absolute values) reduced (?29·9 cps) in CorT responders and tended (P = 0·067) to differ from variations occurred in non‐responders (+6·9 cps in patients with maintained CAS positivity post‐treatment). Higher baseline ROI‐ratios (4·9 versus 3·3; P = 0·056) and its pronounced reductions following CorT (?37% versus +56% in non‐responders; P = 0·036) tended to be associated with good CorT responses in the subgroup of GO history ≥1 year. SCI showed a good association with active eye disease and may be an additional tool to identify CorT responders.