The frequency of a radiographic parenchymal abnormality in an individual with polymyositis is low (ranges around 5%). If present and not complicated with any other problem, it is usually appreciated as a symmetric, basal predominant basal reticular pattern which can progress to being more diffuse with time. Areas of consolidation (often bilateral) may develop in some patients.
Some patients may have an elevated diaphragm from diaphragmatic paralysis.
Initial CT findings of pulmonary involvement in patients can include
- considered characteristic and reversible CT findings 2
- other findings
- honeycombing: may develop in some patients
A proportion of patients may have a pattern somewhat resembling that of cryptogenic organising pneumonia.
Imaging features can often overlap pulmonary manifestations of dermatomyositis
- 1. Kim EA, Lee KS, Johkoh T et-al. Interstitial lung diseases associated with collagen vascular diseases: radiologic and histopathologic findings. Radiographics. 2002;22 Spec No (suppl_1): S151-65. doi:10.1148/radiographics.22.suppl_1.g02oc04s151 - Pubmed citation
- 2. Akira M, Hara H, Sakatani M. Interstitial lung disease in association with polymyositis-dermatomyositis: long-term follow-up CT evaluation in seven patients. Radiology. 1999;210 (2): 333-8. doi:10.1148/radiology.210.2.r99ja15333 - Pubmed citation
- 3. Mino M, Noma S, Taguchi Y et-al. Pulmonary involvement in polymyositis and dermatomyositis: sequential evaluation with CT. AJR Am J Roentgenol. 1997;169 (1): 83-7. doi:10.2214/ajr.169.1.9207505 - Pubmed citation
- 4. Ikezoe J, Johkoh T, Kohno N et-al. High-resolution CT findings of lung disease in patients with polymyositis and dermatomyositis. J Thorac Imaging. 1997;11 (4): 250-9. Pubmed citation
- 5. Douglas WW, Tazelaar HD, Hartman TE et-al. Polymyositis-dermatomyositis-associated interstitial lung disease. Am. J. Respir. Crit. Care Med. 2001;164 (7): 1182-5. doi:10.1164/ajrccm.164.7.2103110 - Pubmed citation