Approach to the diagnosis of sialadenosis using sialography

Since parotid swelling is the most informative symptom of sialadenosis, we examined parotid swelling with sialography as a means of diagnosing sialadenosis. An X-ray was taken from a fixed position relative to the body, using a focus film distance (FFD) of 70 cm. To determine an "index" of parotid swelling, the distance between the submandibular bone ridge and the end of the main duct was measured on X-ray. After examination of 30 normal parotids, abnormal swelling was defined as an "index" exceeding 1.9 cm. Sixteen of 24 patients suspected of having sialadenosis showed swelling exceeding 1.9 cm. Six of 7 patients who were histologically diagnosed with sialadenosis showed swelling in excess of 1.9 cm. Our method is reproducible and recurrence of parotid swelling correlating with sialadenosis can be objectively demonstrated. Furthermore, serum amylase levels in patients who were diagnosed with sialadenosis were measured before and after sialography. After sialography serum amylase levels increased remarkably higher than those of normal subjects. Thus if a patient with underlying diseases has an "index" over 1.9 cm and his serum amylase level after sialography increases remarkably, a diagnosis of sialadenosis is likely.