Diffuse Parenchymal Abnormalities in Acutely Dyspneic Patients: A Pattern-based Approach.

Levesque, Marie-Helene; Montesi, Sydney B; Sharma, Amita

Acute dyspnea is a common presenting complaint in the Emergency Room. Evaluation with chest radiography is vital for initial assessment and may reveal diffuse parenchymal abnormalities that require further assessment with computed tomography (CT). The aim of this review is to outline a pattern-based approach for the analysis of diffuse pulmonary abnormalities in an acutely dyspneic patient with emphasis on CT appearances. Specific disease entities may be differentiated by their distribution in the lungs and by their radiologic findings. Recognition of the predominant finding and its distribution can generate an appropriate differential diagnosis that is further refined by the presence or absence of ancillary findings. Incorporation of the clinical history, laboratory data, and prior studies narrows the differential diagnosis, indicates the optimum modality for further evaluation, and, in some situations, provides important prognostic data.