INVASIVE PULMONARY ASPERGILLOSIS - MRI, CT, AND PLAIN RADIOGRAPHIC FINDINGS AND THEIR CONTRIBUTION FOR EARLY DIAGNOSIS

prospective study was conducted in 38 patients with nodular lesions on plain chest radiographs and the clinical suspicion of invasive pulmon ary aspergillosis (IPA) to assess the diagnostic accuracy of magnetic resonance imaging (MRI) and computed tomography (CT). For early diagno sis of IPA (clinical signs and symptoms <10 days), CT scans with demon stration of the halo sign had a high sensitivity (16/22) and specifici ty (8/8). Magnetic resonance imaging performed at the same time reveal ed a relatively higher sensitivity (22/22), but a very poor specificit y (0/8). Gadolinium-diethylene-triamine-pentaacetic acid (Gd-DTPA) enh anced images did not improve specificity. In the later course of infec tion (clinical signs and symptoms >10 days), MRIs showed typical nodul ar target-like lesions with Gd-DTPA enhancement of the rim area that w as not seen in the early course of the disease or in patients with Pse udomonas or staphylococcal infection. In conclusion, MRI findings are not as characteristic as the CT halo sign in diagnosing IPA in the ear ly course of the disease, but the MRI target sign with Gd-DTPA enhance ment of the rim area and the ''reverse target'' on T-2-weighted images are strongly suggestive of IPA at a later stage of the disease.