Lung scintigraphy with [123I]IMP in patients with pulmonary tuberculosis

Lung scintigraphy using N-isopropyl-p-[¹²³I]iodoamphetamine (IMP) was performed on 26 patients with pulmonary tuberculosis. Early (5 min after injection) and late images (4 h after injection) were obtained with a large-field γ-camera equipped with a digital computer. Lung scintigraphy using [^99mTc]MAA (MAA) was also done. Although early IMP images showed the same findings as [^99mTc]MAA images, a discrepancy between delayed IMP images and [^99mTc]MAA images was seen in some patients. Increment of activities seen in late images was demonstrated in most patients whose chest x-ray findings included exudative inflammatory changes. Uptake and clearance of IMP was considered to be affected by the active phase of pulmonary tuberculosis.