Objective: We introduce a new technique for the functional evaluation of the salivary glands using continuous magnetic resonance (MR) sialography before and after citric acid stimulation.
Methods: In 10 volunteers, the time-dependent changes in the maximum area of the detectable parotid gland ducts on MR sialographic images taken every 30 seconds before and after citric acid stimulation were analyzed. The time period to the occurrence of the maximum duct area poststimulation was noted, and then the time for the area to return to its 50% value pre-citric acid stimulation was also observed. This new technique was clinically applied in 1 patient with an excessive supply impression of saliva and in 1 patient with a short supply impression with saliva.
Results: In all volunteers after citric acid stimulation, the maximum area of the detectable salivary gland ducts first increased and then decreased. A strong relationship was found between the maximum area of the detectable salivary gland ducts before citric acid stimulation and total saliva volume (Pearson r = 0.672, P = .031). Compared with all the volunteers, the ratio of change in the detectable ducts was the highest in the patient with an excessive supply impression of saliva, but lowest in the patient with a short supply impression with saliva.
Conclusions: This initial study suggests that dynamic MR sialography allows for functional and morphological evaluation of the salivary glands. This technique appears to have many possible applications and further investigation in this field is necessary.