OBSERVER VARIATION AND RELATIONSHIP OF COMPUTED-TOMOGRAPHY TO SEVERITY OF BERYLLIUM DISEASE

Although high resolution computed tomography (HRCT) is commonly used t o assess interstitial lung disease (ILD), relatively little is known a bout interrater reliability and construct validity of HRCT-reported no dules, ground-glass opacity, or other typical findings. We determined the interobserver and intraobserver variability of HRCT findings and c orrelated HRCT abnormalities with physiologic measures in 57 patients with chronic beryllium disease (CBD). Reliability of HRCT scan measure ments were assessed using weighted kappa (K-w) and intraclass correlat ion coefficients. We correlated HRCT with spirometry, body plethysmogr aphic lung volumes, diffusing capacity for carbon monoxide (DLCO), max imal exercise testing with measurement of arterial blood gases, and br onchoalveolar lavage (BAL). Interobserver agreement for three of the H RCT abnormalities found in CBD was moderate: the Kw for nodules, septa l lines, and ground-glass attenuation were 0.53, 0.44, and 0.53, respe ctively. Agreement was poor for bronchial wall thickening (K-w 0.15). HRCT scores correlated significantly with DLCO, gas exchange at rest a nd at maximal exercise, and lung volume. This study demonstrates that HRCT has good interrater reliability and correlates with indices of th e severity of granulomatous lung diseases such as CBD.