The normal CXR shows the characteristic asymmetric branching of the main stem bronchi. The right is short and stout and slightly more vertical while the left is long and thin and slightly more obtuse.
The normal carinal angle is between 40-80 degrees.
Ashley Davidoff MD
CARINAL ANGLE – 40-80 degrees
Ashley Davidoff MD
THE LEFT – TALL THIN AND GRACILE
The carinal angle
http://www.wikiradiography.net/
Courtesy Radiopaedia
Courtesy Radiopaedia
Carinal Angle – Normal
The Wright Brothers Take a Walk (Take a look at the crotch angle)
Library of Congress
The branching pattern of the tracheobronchial tree is like the asymmetric branching of most trees – just upside down
The classical branching pattern of many trees
Ashley Davidoff MD
Widened Carinal Angle – The Enlarged Left Atrium
Origin Big Gallery
35 year old patient with severe mitral stenosis . with left atrial enlargement (LAE) characterized by elevation of the left mainstem bronchus, straightening of the left heart border, and prominence of the upper 1/3 of the posterior border of the heart. The right atrium is also enlarged characterized by a rotund right heart border. There is right ventricular enlargement characterized by filling in of the retrosternal airspace.
Ashley Davidoff MD
The Kick or the Dance – Widening of the carinal (crotch) angle
Margot Fonteyn dancing with Rudolf Nureyev during a rehearsal of Roland Petit’s Paradise Lost at Covent Garden in London in 1967 (PA Archive/PA)
Jim Sullivan kicking for England, in a rugby league match against Australia, 1933
“The mean angle of tracheal bifurcation is 60° (+/- 10° ), i.e. 95% of the patients have normal values between 40-80 °. The angle decreases by 10° on expiration. Also, the angle varies, sometimes by 20%, in serial radiographs.”