Posterior inferior junction line and left pleuroesophageal stripe: their association with emphysema.

In an effort to define the posterior inferior junction line (PIJL) and its clinical associations more precisely, 64 posteroanterior radiographs demonstrating the PIJL or left pleuroesophageal stripe (LPES) were analyzed for the presence of emphysema, kyphosis, air-filled esophagus, and/or tortuous aorta. Pursuant to the possible association of a PIJL or LPES with an air-filled esophagus, posteroanterior radiographs of 66 patients with achalasia were evaluated for the presence of a PIJL or LPES. To determine the components of the PIJL or LPES, 50 randomly selected computed tomographs (CT) of the chest were reviewed. Finally, 118 posteroanterior radiographs of patients with emphysema were analyzed for the presence of a PIJL and/or LPES to determine the sensitivity of the line/stripe for emphysema. The finding of a PIJL and/or LPES had a combined sensitivity of 23% for emphysema. Although certain other anatomic constructs lead to the presence of a line or stripe, emphysema is the most commonly associated clinical entity with a positive predictive value of 65.8%. The line and/or stripe is formed by interfaces between lung/lung, lung/esophagus, or both at different levels.