Somatostatin receptor scintigraphy to predict the clinical evolution and therapeutic response of thyroid-associated ophthalmopathy.
Management of thyroid-associated ophthalmopathy remains a topic of controversy. Immunosuppressive treatments have to be applied at peak disease activity and before criteria of severity develop. Expression of somatostatin receptors on activated lymphocytes allows scintigraphic imaging with indium-111 pentetreotide. We conducted a prospective study with 17 patients who presented severe ophthalmopathy (11 Graves' disease, four Hashimoto's thyroiditis, two isolated in appearance: Means' syndrome). Each patient underwent hormonal (free T3 and TSH) and immunological (TBII) assessment, an orbital computed tomography scan or magnetic resonance imaging, a visual functional examination and 111In-pentetreotide orbital scintigraphy before undergoing treatment by steroids and/or radiotherapy, independently of scintigraphic results. At 4 and 24 h after the intravenous injection of 111 MBq of 111In-pentetreotide, planar imaging centred on the head and neck (anterior and both lateral views) was carried out. Retrobulbar uptake was assessed by visual semi-quantitative analysis (score given by two independent trained observers) and by quantitative analyses (regions of interest, orbit/brain uptake indices). Patients were ophthalmologically followed up for 6 months and then classified as improved or not. Visual semi-quantitative analysis of 4-h/24-h planar images was correlated with the ophthalmological evolution (chi 2 test, P < 0.01). All ten patients in whom scintigraphy was considered positive were clinically improved at 6 months, and of the seven patients in whom scintigraphy was negative, six were not improved. Nevertheless, objective quantitative analysis did not succeed in confirming these results. We conclude that 111In-pentetreotide scintigraphy requires further developments, including quantitative single-photon emission tomographic acquisition, if its role as a guide to therapeutic strategy in thyroid-associated ophthalmopathy is to be confirmed.
Nocaudie
M
M
Service Central de Médecine Nucléaire et Imagerie Fonctionnelle, Centre Hospitalier Régional et Universitaire de Lille, France.
Bailliez
A
A
Itti
E
E
Bauters
C
C
Wemeau
J L
JL
Marchandise
X
X
D005260:Female; D005500:Follow-Up Studies; D006111:Graves Disease / Q000000981:diagnostic imaging* / Q000628:therapy; D006801:Humans; D007205:Indium Radioisotopes; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin / Q000032:analysis*; D013004:Somatostatin / Q000031:analogs & derivatives*; D013997:Time Factors; D016896:Treatment Outcome
D007205:Indium Radioisotopes; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin; D013004:Somatostatin; C081788:pentetreotide