Nipple Shadows on Chest X-Ray

Classic Nipple Shadows

* Bilateral symmetric
* Fuzzy margins with radiolucent halo, or sharp lateral but poorly defined medial margins
* Characteristic location (fifth or sixth anterior ribs or near bottom of breast shadow)
* Not present on a very recent film
* Could be identified on lateral film

Problems

* Nipple shadows can be seen in up to 10% of chest radiographs
* Although most of these can be resolved as 'classic nipple shadows' and no further imaging is needed, about 1.4% need repeat examination
* Repeat examinations are related to increased cost, time and burdensome to patients

Nipple Markers

* A 1.5 mm lead shot that, given its size, should not obscure a true pulmonary nodule
* Very helpful to determine whether the suspicious nodule is actually a nipple shadow, or not.
* Chance of having a true pulmonary nodule lying beneath the nipple shadow is very slim

Reference:
Miller WT, et al. The troublesome nipple shadow. AJR 1985 (September)