Section Editor: Sandy Cheng-Yu Chen, M.D.
Taipei Medical University Hospital, Taipei, Taiwan
Retropharyngeal abscesses in adults are usually pyogenic as a result of esophageal or pharyngeal perforation due to injury such as a penetrating foreign body (fish bone). Retropharyngeal cold abscess is rare and often secondary to Pott’s spine, a tuberculous infection. It may also occur due to involvement of a retropharyngeal lymph node by lymphatic spread in the absence of spinal involvement. Tuberculous infection is the most common opportunistic HIV-related infection throughout the world. The diagnosis can be made using the appropriate clinical history and the classic MRI findings, which include a well-circumscribed and space-occupying lesion in the retropharyngeal space (A and B, arrows). Postcontrast fat-saturated T1WI shows a thick enhancing wall (B, arrows) of the abscess cavity. The adjacent vertebrae show no abnormality.