Elsevier

Clinical Radiology

Volume 53, Issue 7, July 1998, Pages 510-514
Clinical Radiology

MRI signal characteristics of progressive massive fibrosis in silicosis

https://doi.org/10.1016/S0009-9260(98)80171-2Get rights and content

Aim: To determine the magnetic resonance imaging (MRI) signal characteristics of progressive massive fibrosis (PMF) in silicosis.

Subjects and Methods: We evaluated prospectively the MR appearances in 17 patients with 34 PMF lesions on the basis of pre-contrast signal intensity (SI) and SI pattern and post-contrast enhancement pattern, using a 0.5-T unit. There were 13 PMF lesions in six patients who had silicosis and 21 PMF lesions in 11 patients who had silicotuberculosis. The SI pattern on T2-weighted image (WI) was classified into four types and the pattern of contrast enhancement on T1-WI was classified into three types. MR appearances of PMF lesions were correlated with the findings of computed tomography (CT).

Results: The commonest signal intensity characteristic was isointensity (70%) on T1-WI and hypointensity (68%) on T2-WI when compared with skeletal muscle. For signal pattern on T2-WI, a type with only internal high SI areas (46% in silicosis group, 38% in silicotuberculosis group) was most frequent. All of these areas corresponded to the low density areas at CT, suggestive of necrosis. After intravenous contrast medium enhancement, rim enhancement (54% in silicosis group, 52% in silicotuberculosis group) was most frequent, followed by no enhancement.

Conclusion: The most common MRI appearance of PMF was isointensity on T1-WI and hypointensity on T2-WI when compared with skeletal muscle, with internal high SI areas on T2-WI and either rim enhancement or no enhancement.

References (14)

  • SpencerH

    Pathology of the Lung: the Pneumoconiosis and Other Occupational Lung Diseases

  • KleinermanJ et al.

    Pathology standards for coal workers' pneumoconiosis

    Archives of Pathological Laboratory and Medicine

    (1979)
  • WilliamsJL et al.

    Solitary mass in the lungs of coal miners

    American Journal of Roentgenology

    (1973)
  • BeginR et al.

    CT assessment of silicosis in exposed workers

    American Journal of Roentgenology

    (1987)
  • BerginCJ et al.

    CT in silicosis: Correlation with plain films and pulmonary function tests

    American Journal of Roentgenology

    (1986)
  • HirakataK

    Pathologic-HRCT correlation of pneumoconiosis: A study on infiltration-fixed lungs

    Japanese Radiological Society

    (1992)
  • OhtaT et al.

    Histological evaluation of lung cancer with T2-weighted magnetic resonance images

    Nippon Kyobu Shikkan Gakkai Zasshi

    (1995)
There are more references available in the full text version of this article.

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