UPPER AIRWAY X-RAY | LATERAL PROJECTION

Pathology Demonstrated:

Upper Airway Lateral View Radiograph

• Pathology is of the air filled larynx and trachea, including the region of thyroid and thymus glands and upper esophagus for opaque foreign object or if contrast medium is present. Soft tissue lateral frequency is taken to rule out epiglottis, which may be life threatening for young child.

Technical Factor:

• IR size - 24 x 30 cm (10 x 12 inches), lengthwise.
• Moving or stationary grid
• 80 or add upto 6 kV range (see note below)

Shielding:

• Secure lead shield around waist to shield gonads.

Patient Position:

• Patient should be upright if possible, seated or standing in a lateral position (may be taken in R or L lateral and may be taken recumbent tabletop if necessary).

Part Position:

• Position patient to center upper airway to CR and to center of IR ( larynx and trachea lie anteior to cervical and thoracic vertebrae).
• Rotate shoulders posteriorly with arms hanging down and hands clasped behind back.
• Raise chin slightly and have patient look directly ahead.
• Adjust IR height to place top of IR at level of external auditory meatus (EAM), which is the opening of the external ear canal. (see below if area of primary interest is the trachea rather than the larynx.)

Central Ray:

• CR perpendicular to center of IR at level of C6 or C7, midway between the laryngeal prominence of the thyroid cartilage and the jugular notch.
• SID of 72 inches (180cm), if possible, to minimize magnification

Collimation:

• Collimate to area of interest.

Respiration:

• Male exposure during slow, deep inspiration to ensure filling trachea and upper airway with air.

Note on centering and exposure for neck region:

• Centering should be to laryngeal prominence (C5) with exposure factors for a soft tissue lateral neck if the area of interest is primarily the larynx and upper trachea.

Note on Centering and exposure for distal larynx and trachea region:

• If the distal larynx and the upper and midtrachea are the primary areas of interest, the IR and CR should be lowered to place the CR at the upper jugular notch (T1) with exposure factors approximately those for a lateral chest.