Radiology · patient case question
Ring-shaped radiopacities are superimposed over the left maxillary sinus region. What are they most likely to be?
Patient case: Reading the panoramic film
demo: Series of radiographic interpretation items
chief: Assorted radiographic findings and technique errors from a single clinic session.
history: Several patients imaged the same morning; the films are reviewed together at the end of the day.
meds: Not applicable.
findings: One panoramic film shows the right ramus and posterior teeth appreciably wider than the left. Another shows two ring-shaped radiopacities superimposed over one maxillary sinus and three over the other, in a patient wearing earrings. A third shows a curved radiopacity in the lower field. An occlusal film shows a soft tissue shadow over the incisal edges of the anterior teeth.
Show answer and explanation
Correct answer: A. The right earring, projected across the midline
- A. Correct. Panoramic imaging produces ghost images: an object between the source and the centre of rotation projects across to the opposite side, higher, larger and blurred. The right earring therefore appears over the left side. The real left earring also appears, on its own side and sharper.
- B. The true left earring image would sit on the left but would be sharp and in its correct anatomical position rather than projected up over the antrum.
- C. Nothing in the history suggests trauma or surgery, and the ring shapes correspond directly to the jewellery.
- D. Antroliths are irregular mineralised concretions within the sinus and would not appear as concentric rings that match the earrings the patient is wearing.
Note: The practical lesson comes first: all jewellery, hairpins, dentures and removable appliances come off before a panoramic exposure. When a ghost appears, remember it projects to the opposite side, higher and magnified.