Which is the following is not true about acute retropharyngeal abscess

ACUTE RETROPHARYNGEAL ABSCESS AETIOLOGY :- It is commonly seen in children below 3 years. It is the result of suppuration of retropharyngeal lymph nodes secondary to infection in the adenoids, nasopharynx, posterior nasal sinuses or nasal cavity. In adults, it may result from penetrating injury of posterior pharyngeal wall or cervical oesophagus. Rarely, pus from acute mastoiditis tracks along the undersurface of petrous bone to present as retropharyngeal abscess. CLINICAL FEATURES :- 1. Dysphagia and difficulty in breathing are prominent symptoms as the abscess obstructs the air and food passages. 2. Stridor and croupy cough may be present. 3. Toicollis. The neck becomes stiff and the head is kept extended. 4. Bulge in posterior pharyngeal wall. Usually seen on one side of the midline. Ref:- Dhingra; pg num:-266