On the Diagnostic Imaging of Solitary Pulmonary Nodule (SPN)

The difference in 201TI-choride (201TI) accumulation on single photon emission computed tomography (SPECT) between 58 benign (58 cases) and 48 malignant (46 cases) thoracic lesions, each of more than 20mm in diameter was investigated. In the 34 benign and 48 malignant lesions depocted in both early (15min) and delayed uptake ratios of lesion to normal contralateral lung between benign and malignant. However, the retention index in the lesion derived from (delayed ratio-early ratio) / early ratio×100% showed a significant difference (benign -4.30±18.9%, P<0.01) indicating the poor 201TI retention in the benign lesions. Using the criteria of nondepiction in the delayed image or a negative retention index, 81.1% accuracy and 95.2% predictive value for diagnosis of benign lesions were obtained. Thus, 201TI SPECT appears to have potential usefulness in the diagnosis og benign thoracic lesions.

Foramen magnum tumor

Meningioma

Magnetic resonance imaging