Effectiveness of Tc-99m sestamibi compared to Ga-67 in patients with pulmonary sarcoidosis

Technetium-99 m sestamibi imaging in patients with subacute thyroiditis

To determine if subacute thyroiditis (SAT) is associated with changes in the regional perfusion of the thyroid gland, we performed Tc-99 m sestamibi scans on eleven patients with SAT who had painful goiter and clinical thyrotoxicosis. Eleven patients had Tc-99 m pertechnetate and Tc-99 m sestamibi scintigraphy during the acute stage of SAT. The thyroid uptake ratio of sestamibi was compared with the laboratory data and color Doppler ultrasonography. Tc-99 m pertechnetate scintigraphy in the thyroid was markedly reduced during the acute stage of SAT. Conversely, Tc-99 m sestamibi showed diffuse increased uptake in the thyroid region, suggesting increased perfusion. On the other hand, there was near absence of vascularization in the acute phase and slight increase in the recovery phase by color Doppler ultrasonography. The clearance rate of Tc-99 m sestamibi during the early phase (from 10 min to 1 h) was decreased in the acute stage of SAT. The sestamibi uptake ratio correlated with serum immunosuppressive acidic protein (IAP) in the acute stage of SAT and the sestamibi uptake ratio in the recovery stage of SAT was correlated with serum thyrotropin levels. Tc-99 m sestamibi uptake in the early phase in the acute stage of SAT may reflect the inflammatory process associated with SAT.

Tc-99m sestamibi before and during treatment in a patient with sarcoidosis and persistent hyperparathyroidism

PURPOSE

Tc-99m sestamibi (MIBI) uptake in pulmonary sarcoidosis has been reported, but it has never been studied before and during treatment with glucocorticoids.

METHODS

The authors performed MIBI scintigraphy and somatostatin receptor scintigraphy in a patient with sarcoidosis of the mediastinum, lungs, and liver and who had persistent hyperparathyroidism after unsuccessful neck exploration.

RESULTS

Somatostatin receptor scintigraphy showed high mediastinal and pulmonary uptake in a pattern characteristic of sarcoidosis. Sustained MIBI uptake occurred in the same, although smaller, region. After the diagnosis was confirmed by liver biopsy, the patient was treated with glucocorticoids. Repeated MIBI scintigraphy showed that the uptake in the mediastinum had clearly decreased.

CONCLUSIONS

This decrease of MIBI uptake in the mediastinal lymph nodes with therapy may imply that MIBI can be used to assess the response to treatment in sarcoidosis. Perhaps a relation exists between MIBI uptake at the moment of diagnosis and prognosis. Further studies in more patients are needed to evaluate the role of MIBI in the management of sarcoidosis.