Acute orbital infection is a potentially serious condition in which the patient is at risk of blindness in the affected eye, and may develop intracranial complications. Orbital abscesses, which are usually subperiosteal and lie beneath the orbital roof, require surgical drainage. Their identification is a diagnostic challenge. The reliability of computed tomography (CT) in demonstrating subperiosteal abscesses has been questioned but all 15 abscesses in a series of 25 cases of orbital infection were satisfactorily demonstrated provided the CT examination included coronal sections. One-third of abscesses would have been missed if coronal sections had been omitted.