Topics

Topic

design image
Left paratracheal stripe

The left paratracheal stripe is a thin linear radiographic interface occasionally visible on frontal chest radiographs. It represents the interface between the air-filled trachea and the adjacent left mediastinal soft tissues and pleura. Unlike the right paratracheal stripe, it is less consistently visible due to overlapping vascular structures.

Recognition of the left paratracheal stripe is useful in assessing mediastinal anatomy and subtle contour changes on chest X-ray.

Synonyms

  • Left paratracheal line

  • Left tracheomediastinal stripe

Location

  • Seen along the left lateral border of the trachea

  • Extends from the thoracic inlet inferiorly

  • Usually visible only in the upper mediastinum

  • Located medial to the left upper lung field

  • Partially obscured inferiorly by the aortic arch

Anatomical basis

  • Air column of the trachea (medial component)

  • Left mediastinal soft tissues, including:

    • Paratracheal connective tissue

    • Left paratracheal lymph nodes

    • Mediastinal pleura

  • Adjacent vascular structures, especially the aortic arch, which limit visibility

Relations

Medially:

  • Tracheal air column

Laterally:

  • Left upper lobe of the lung

Anteriorly:

  • Superior mediastinal soft tissues

Posteriorly:

  • Paratracheal region and upper thoracic spine

Superiorly:

  • Thoracic inlet

Inferiorly:

  • Aortic arch (limits inferior extent of visibility)

X-ray appearance

Chest radiograph (PA view):

  • Appearance: Thin vertical or slightly oblique soft-tissue stripe adjacent to the left side of the trachea

  • Thickness: Typically ≤4 mm when visible

  • Margins: Smooth and well defined

  • Extent: Usually shorter than the right paratracheal stripe

  • Visibility: Inconsistently seen due to overlap from the aortic arch and great vessels

  • Comparison: Less prominent and less consistently visualized than the right paratracheal stripe

X ray image

Left paratracheal stripe x ray Anatomy, Location and Imaging Appearance CT anatomy image -img-00000-00000