Transaxial Ga-67 tomography in pulmonary asbestosis

Fourteen patients with known asbestosis underwent both planar and single photon emission CT (SPECT) imaging of the thorax. The SPECT study comprised 64 views over a 3600 transaxial rotation. Abnormal Ga-67 activity was present in 9 of 14 planar studies and in all 14 SPECT studies, compared to established normal values. SPECT findings, correlated well with disease severity as estimated by clinical and pulmonary function testing but not with radiographic changes. Repeat SPECT on four patients after treatment showed improvement but not normalization of function. SPECT more accurately than planar studies indicates the presence and extent of the inflammatory alveolitis component of astestosis and is useful in determining response to therapy