Ghost image (orthopantomogram)

Last revised by Andrew Murphy on 23 Mar 2023

Citation, DOI, disclosures and article data

Citation:

Murphy A, Haouimi A, Hacking C, Ghost image (orthopantomogram). Reference article, Radiopaedia.org (Accessed on 16 Apr 2024) https://doi.org/10.53347/rID-75834

DOI:

https://doi.org/10.53347/rID-75834

Permalink:

https://radiopaedia.org/articles/75834

rID:

75834

Article created:

8 Apr 2020, Andrew Murphy ◉

Disclosures:

At the time the article was created Andrew Murphy had no recorded disclosures.

View Andrew Murphy's current disclosures

Last revised:

23 Mar 2023, Andrew Murphy ◉

Disclosures:

At the time the article was last revised Andrew Murphy had no financial relationships to ineligible companies to disclose.

View Andrew Murphy's current disclosures

Revisions:

4 times, by 3 contributors - see full revision history and disclosures

Systems:

Head & Neck

Sections:

Radiography

A ghost image is a commonly observed artifact in an orthopantomogram whereby a dense, often metallic object is located between the source of x-ray and the focal center, resulting in a duplicate 'ghost' image at the contralateral aspect of the image.

Real image vs ghost image

In panoramic image such as the orthopantomogram, structures within the focal trough (a panoramic arch similar to that of the teeth) will be sharp, well defined and overall lacking in distortion. Objects outside of this focal trough that are dense enough to attenuate x-rays will occasionally present twice as the x-ray tube rotates around the patient, this is known as a ghost image. The density will appear at the true location and secondly on the contralateral aspect of the image as a distorted 'ghost' image. The ghost image is distorted and larger than the actual object projected and often not at the same height ¹.

Practical points

When positioning for an orthopantomogram take into account any metallic objects on the patient's face and head can impact the image. This includes earrings, cheek piercings and hair clips.