Tram track sign may be used in chest radiography or ct to denote the thickened non tapering parallel walls of cylindrical bronchiectasis. Implies non uniform bronchial dilatation.
When found in the lungs tram tracks are radiologic signs that are usually accompanied by pulmonary edema in cases of congestive heart failure and bronchiectasis tram tracks are caused by bronchial wall thickening and can be detected on a lateral chest x ray.
Tram track appearance x ray. Now compare the previous x ray with the one above here are few examples of tram line shadows. Adequate passage of barium into the stomach was noted in 14 patients and fundus showed normal appearance in all these patients. The tram track sign may be explained by the presence of thickened bronchial branches on radiographs black arrowheads in a and b which reproduce a tram line appearance clearly shown on c.
Look for tram track parallel lines around the hila. Mild form shows tram track appearance. Tram track appearance of the narrowed segment was noted in 17 57 patients figure 3.
Tram track sign can be seen on ct and cxr. There is dilatation of bronchi with or without thickening of bronchial walls and mucus plugging. The usual causes are viral infection or asthma but this is a common finding with cystic fibrosis.
The dilated airway lies adjacent to a pulmonary artery branch giving the appearance of a ring varicose. This description applies to dilated airways seen in a horizontal orientation. Bronchial wall thickening is a common finding on children s x rays.
It should not be confused with other tram track signs elsewhere in the body. This describes airways viewed in a transverse plane. Case discussion the tram tack sign seen on this chest x ray denoted thickened non tapered walls of the cylindrical bronchiectasis.
What was seen on the chest x ray it is nothing but the tram line appearance unable to spot it here comes the modified image. The anterior mediastinum in front of the heart contains the thymus gland. The term tram tracks is also used to describe the basement membrane duplication found on light microscopy.
Cylindrical tram track sign. The coronal ct image shows thickened bronchial branches cylindrical bronchiectasis. The tree in bud sign and the signet ring sign can be seen on ct.
In d the same appearance could be also described in a ct of a patient with cystic fibrosis. It approached the height of two vertebral bodies in 10 patients and was less than one vertebral body height in 6 patients. Tram track sign annotated in a 65 year old male with diagnosed bronchiectasis secondary to dilated bronchi within both lower lobes.