Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are diffuse bilateral opacities , ? combined insterstial and alveolar opacities , with suggestion of faint nodular opacities in both lungs . No air bronchograms are identified . No effusion is seen . Heart size is borderline enlarged . The cardiomediastinal silhouette appears slightly more prominent in comparison to prior study . Post - surgical changes are noted in the cervical spine with fusion .
    OUTPUT:
    
Diffuse bilateral opacities . The differential diagnosis for an acute or subacute process includes pulmonary edema or an infectious or inflammatory etiology . Given the history of fever , infeciton should be considered . Pulmonary edema may be somewhat less likely given the absence of effusions . If this were a chronic process , other etiologies would be considered .