Somatostatin analogs represent a novel alternative to Ga. In an early report focusing on In-P, this technique detected new sites of granulomatous activity in 9 of 13 patients. In a larger series of 46 individuals with sarcoidosis, Kwekkeboom and colleagues noted that In-P detected known adenopathy and parenchymal involvement in 97% of cases. In-P identified new sites of sarcoidosis activity in 50% of subjects. On repeat scanning, In-P activity diminished in each of these trials among the patients treated with corticosteroids. In-P imaging also appears to be more accurate than Ga imaging.’ Lebtahi et al compared Ga imaging to In-P imaging in 18 persons with sarcoidosis. Although Ga imaging localized to two thirds of the clinically involved sites, In-P imaging detected 83% of areas of clinical sarcoid activity. One concern with In-P imaging is its limited ability to locate extrapulmonary sarcoidosis. For example, in the trial conducted by Lebtahi et al,In-P imaging failed to reveal several known cases of neurosarcoidosis and, overall, missed approximately 40% of all extrathoracic lesions. Technical factors also limit the utility of In-P scintigraphy in that patients must return for repeat image acquisition 24 h after initial injection. buy glucotrol online
No other systematic trial has examined 99mTc-DP imaging in sarcoidosis. Anecdotal reports initially indicated that 99mTc-DP imaging might lead to false-positive results in the evaluation of suspected pulmonary malignancies. Our preliminary observations underscore the potential role that 99mTc-DP imaging may have in sarcoidosis. 99mTc-DP imaging correlated well with CXR findings, which are perhaps the strongest predictor of outcome in sarcoidosis patients. 99mTc-DP imaging, unlike the performance of Ga in other studies, correctly staged almost all subjects with sarcoidosis. Furthermore, the relationship between lung tissue uptake and the results of certain PFTs suggests that 99mTc-DP imaging may detect the extent of lung injury arising from sarcoidosis.