Unilateral Hot Vocal Cord

The vocal cords and laryngeal structures normally demonstrate little or no metabolic activity.  

If a patient speaks after FDG injection, however (patients routinely sneak out their cell phones and have lengthy conversations), the vibrating vocal cords and cricoarytenoid muscles can become intensely avid.

Consequently, bilateral intense uptake in the vocal cords and/or cricoarytenoid muscles is almost always normal — in the absence of an associated CT abnormality.

Unilateral vocal cord uptake, however, is not a normal finding and warrants careful assessment by the radiologist.

While the unilateral hot vocal cord may represent a primary laryngeal cancer (covered here), not infrequently it reflects normal physiologic uptake in a patient with contralateral vocal cord paralysis, who has vocalized after FDG injection.

In the case of unilateral vocal cord paralysis, the paralyzed vocal cord will be non-avid, while the normal vocal cord will appear hot (if the patient was speaking after FDG injection).

In such cases, the diagnosis is confirmed by the CT images, where the paralyzed side will often demonstrate thickening and medial positioning of the aryepiglittic fold, dilatation of the pyriform sinus and vallecula, anterior positioning of the arytenoid cartilage, and prominence of the affected vocal cord.