Synovial Cyst of the Temporomandibular Joint: Report of a case

Temporomandibular joint synovial cysts: A systematic review of the literature and a report of two cases

Temporomandibular joint (TMJ) synovial cysts are rare, unlike peripheric locations like the wrist or the knee. They share similar presentations with ganglion cyst, benign and sometimes malignant lesions. Only histopathological analysis confirms diagnosis in some cases, finding a true cyst lined by synoviocytes containing synovial fluid. They seem to be related to an increased articular pressure following trauma. In this study we present two cases of TMJ synovial cyst and a systematic review of the literature. A total of 32 cases were retrieved from published literature in PubMed, Cochrane Library and ClinicalTrials.gov databases using the search terms 'TMJ synovial cyst', 'temporomandibular synovial cyst', 'jaw joint synovial cyst'. Swelling (91.3%) and pain (78.3%) were the most common symptoms. MRI was the most commonly used imaging modality that was found to be beneficial for diagnosis. In almost all cases the cyst was removed under general anesthesia, allowing histopathological examination. Only two patients still had pain after removal of the cyst. No recurrence was observed .

Salivary duct cyst of accessory parotid gland in contact with the temporomandibular joint

A 60-year-old woman presented with a painless swelling in the right preauricular region. Physical examination revealed a soft, nontender, oval-shaped lump in this location. Computed tomography indicated an anterolateral cystic lesion that was attached to the condyle of the mandible and to the accessory parotid gland. Differential diagnoses included ganglion cyst, synovial cyst of the temporomandibular joint, and accessory parotid gland cyst. Surgical removal of the cyst was performed with the patient under general anesthesia. The specimen was 18 × 20 × 18 mm in size; it contained fluid that was clear, slightly yellow, and amylase positive. Hematoxylin and eosin staining revealed that a bilayer cuboidal epithelium lined the cyst wall. Immunohistochemical analyses of the cyst wall showed strong expression of cytokeratin and weak expression of vimentin. The final diagnosis was a salivary duct cyst. The postoperative course was uneventful except for a transient facial motor paresis.

Synovial cyst of the temporomandibular joint: a case report and literature review

Synovial cysts are lesions that usually occur on the wrist, foot and knee. They are rarely involved in the region of the temporomandibular joint (TMJ), with only 10 cases reported from 1978 to 2007. The authors report a case of a synovial cyst of the TMJ in a 45-year-old woman. The patient presented with a right preauricular swelling, 1cm anterior to the tragus. A computed tomography (CT) scan showed a small oval hypodense mass of soft tissue in the right temporomandibular region with no relation to the condyle. Fine needle aspiration reported a synovial cyst of the TMJ. The patient was taken to the operating room and a preauricular approach extending to the temporal region was carried out resulting in surgical excision of the mass. The histological findings were consistent with the diagnosis of a synovial cyst. The long term clinical and radiological follow-up (after 18 months) showed no sign of recurrence. The authors suggest, in accordance with the literature, that a surgical approach should be the treatment of choice in the case of a synovial cyst of the TMJ.