Pott's puffy tumour mimicking preseptal cellulitis.

Periorbital swelling can be secondary to local infections (for example, hordeolum) or reflective of an adjacent infection (for example, dental disease). Rarely, periorbital swelling can indicate underlying sinus disease; Pott's puffy tumour is a unique and serious form of this process. This paper presents an unusual way in which a smouldering sinusitis can erode through bone and result in orbital cellulitis or intracranial infection.