What radiographic sign historically associated with epiglottitis is seen on lateral neck X-ray?

• A. Thumbprint sign
• B. Steeple sign
• C. Sail sign
• D. Widened prevertebral space

Answer: (A)

The main idea here is to recognize a classic radiographic cue of epiglottitis on a lateral neck X-ray. When the epiglottis becomes acutely swollen, it appears as a thick, rounded, posterior bulge over the airway on the lateral view. This bulky, thumb-like projection is called the thumbprint sign, and it reflects the edema of the epiglottis that characterizes this emergency condition.

In contrast, the steeple sign comes from croup and shows up as subglottic narrowing on an AP neck film, not on a lateral view. The sail sign is related to the thymus seen on chest radiographs, not to epiglottitis. Widened prevertebral space can occur with retropharyngeal processes or severe infections, but the distinctive radiographic hallmark for epiglottitis on a lateral neck X-ray is the thumbprint sign.