Silhouetting of right hea border on chest radiograph indicates the presence of pathology in which of the following structure?
Silhouette Sign: Lobe Silhouetted structure Right middle lobe Right hea border Left lingula Left hea border Right lower lobe Right hemidiaphragm Left lower lobe Left hemidiaphragm Post apical segment left upper lobe Aoic knob Anterior segment right upper lobe Ascending aoa Figure: Right middle lobe collapse On frontal projection the right hea border is not clearly seen (blue dashed line). On lateral projection the right middle lobe appears as a wedge of increased density (orange arrows).
Right Upper Lobe
Right Middle Lobe
Right Lower Lobe
Lingula
X-RAYS