EURO PEA N JO URNA L OF RADIO LO G Y European Journal of Radiology 18 (1994) 113-121 zyxwvutsrqponmlkjihgfedcbaZYXWVUTS ELSEVIER SCIENCE IRELAND High-resolution CT and pulmonary function tests in collagen vascular disease: comparison with idiopathic pulmonary fibrosis Takeshi Johkoh*, Junpei Ikezoe, Nobuaki Kohno, Noriyuki Takeuchi, Hidetoshi Yamagami, Noriyuki Tomiyama, Hiroshi Kondoh, Shoji Kido, Jun Arisawa, Takahiro Kozuka zyxwvutsrqponmlkjihgfedcbaZYXWV Department of Radiology, Osaka University, Medical School, 2-2, Yamada-Oka, Suita 662, Japan (Received 14 December 1993; revision received 14 February 1994; accepted 18 February 1994) Abstract To estimate whether the lung abnormalities seen in collagen vascular diseases (CVD) were similar or distinct to those seen in idiopathic pulmonary fibrosis (IPF), and to ascertain whether the extent of the abnormalities on high-resolution CT (HRCT) cor- related with pulmonary function, we reviewed HRCT findings and pulmonary function test results of 64 patients with either CVD (n = 55) or IPF (n = 9). Response to corticosteroid treatment was also evaluated in 20 of the 64. High incidence of honeycomb lesion was observed in IPF (919,lOO?/) and in progressive systemic sclerosis (PSS) (1 l/14,79%). CVD, except for PSS, had a low incidence of honeycomb lesion (27%). On the other hand, incidence of ground-glass shadow in CVD (47/S, 85%) was the same as that in IPF (8/9, 89%). Diffusing capacity significantly correlated with the extent of all parenchymal abnormalities in all CVD and IPF, with honeycomb lesion in PSS, and with ground-glass shadow or air-space consolidation in CVD except for PSS (r < -0.7, P < 0.001). In all 15 cases in which corticosteroid therapy was effective, no honeycomb lesions were seen. Collagen vascular disease, except for PSS, had a different pattern of disease than IPF. The morphologic changes seen on HRCT correlated well with pulmo- nary function in CVD. Key words: Computed tomography, technique; Computed tomography, thorax; Thorax, CT, Thorax, diseases zyxwvutsrqponmlkjihgfed 1. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA Introduction Collagen vascular disease (CVD) is a chronic multisystemic disease characterized by vascular changes, fibrosis, and inflammation of connective tissue. All CVD may involve the respiratory system, but each type may affect it differently. The incidence of lung disease also varies between each type of CVD. Pathological abnormalities of the lung include: usual interstitial pneumonia (UIP), diffuse alveolar damage (DAD), bronchiolitis obliterans organizing pneumonia (BOOP), cellular interstitial pneumonia, lymphocytic interstitial pneumonia, etc. [l-3]. The pathologic finding of idiopathic pulmonary fibrosis (IPF) is almost always l Corresponding author. UIP, except for a few cases of desquamative interstitial pneumonia (DIP). Several studies have suggested that the histologic pattern of both UIP and DIP may be seen in the same patient and have suggested that DIP may represent the early stage and UIP the late stage of the same disease [4,5]. In the management of these patients, accurate assessment of the severity of lung disease and correct prediction of the response to corticosteroid treatment for lung disease are extremely important. In general, UIP has a poor prognosis and does not always respond to corticosteroid treatment [6-S]. Furthermore, some physicians consider that, even if corticosteroid is effective in the acute phase of UIP, the prognosis does not necessarily become better [8,9]. HRCT is considered to be superior to chest radiogra- phy in assessing the presence and extent of parenchymal abnormalities in diffuse infiltrative lung diseases [ 10,111. 0720- 048W 94/S.07.00 0 1994 Elsevier Science Ireland Ltd. All rights resewed. SSDI 0720-048X(94)00525-H