Treatment of intractable parotid sialocele occurred after open reduction-fixation of mandibular subcondylar fracture.

A sialocele is a subcutaneous cavity containing saliva, most often caused by facial trauma or iatrogenic complications. In subcondylar fractures, most surgeons are conscious of facial nerve injury; however, they usually pay little attention to the parotid duct injury. We report the case of a 41-year-old man with a sialocele, approximately 5×3 cm in size, which developed 1 week after subcondylar fracture reduction. The sialocele became progressively enlarged despite conservative management. Computed tomography showed a thin-walled cyst between the body and tail of the parotid gland. Fluid leakage outside the cyst was noted where the skin was thin. Sialography showed a cutting edge of the inferior interlobular major duct before forming the common major duct that seemed to be injured during the subcondylar fracture reduction process. We decided on prompt surgical treatment, and the sialocele was completely excised. A duct from the parotid tail, secreting salivary secretion into the cyst, was ligated. Botulinum toxin was administrated to block the salivary secretion and preventing recurrence. Treatment was successful. In addition, we found that parotid major ducts are enveloped by the deep lobe and extensive dissection during the subcondylar fracture reduction may cause parotid major duct injury.